WO2013099957A1

WO2013099957A1 - Power conversion apparatus

Info

Publication number: WO2013099957A1
Application number: PCT/JP2012/083675
Authority: WO
Inventors: 孝彰則定; 伊藤　和雄; 真小曽根
Original assignee: 三洋電機株式会社
Priority date: 2011-12-28
Filing date: 2012-12-26
Publication date: 2013-07-04

Abstract

A power conversion apparatus relating to the present invention is provided with a power conversion circuit and a control unit. The power conversion circuit adjusts, in accordance with instructions given from the control unit, power supply from a power supply apparatus and/or power demand for a power demand apparatus. The power conversion circuit selectively performs output processing for supplying power to a power auxiliary apparatus, and input processing for obtaining power from the power auxiliary apparatus. The control unit makes the power conversion circuit perform the output processing if the power supply is larger than the power demand, and makes the power conversion circuit perform the input processing if the power supply is smaller than the power demand. When the control unit determines that hunting phenomenon is generated, the control unit gives instructions to the power conversion circuit to have a large difference between the power supply and the power demand.

Description

Power converter

The present invention relates to a power conversion device.

There is a power conversion device that performs power transmission and reception between a power storage device, a power generation device, and a power system through power conversion. In a conventional method, input / output control of a bidirectional converter connected to an electric power system is performed in order to charge a power storage device with a constant current value (charge command amount) while maximizing the output of a photovoltaic power generation device. The charging power value is controlled (see, for example, Japanese Patent Publication No. 6-78473).

However, in the above-described conventional method, when the amount of power generated by the photovoltaic power generation apparatus is near the charge command amount, a phenomenon occurs in which power input / output frequently switches between the power conversion circuit including the bidirectional converter and the power system. Yes. Such a phenomenon is undesirable for the stability of the power system. A similar phenomenon can occur when the power storage device is discharged under certain conditions. In addition, when power is output to the power system under certain conditions or when power is input from the power system, frequent switching of input / output between the power conversion circuit and the power storage device may occur as a phenomenon similar to the above phenomenon. . Such a phenomenon is not preferable for the power storage device.

Therefore, an object of the present invention is to provide a power converter that contributes to suppression of the hunting phenomenon.

The power conversion device according to the present invention includes a power conversion circuit and a control unit. The power conversion circuit includes a power receiving function for receiving power from a power supply device, a power transmission function for supplying power to a power demand device, an output process for supplying power to a power auxiliary device, and an input for acquiring power from the power auxiliary device. An instruction from the control unit is at least one of an input / output selection function for selectively executing processing, supply power that is power received from the power supply device, and demand power that is power supplied to the power demand device And an adjustment function to adjust accordingly. The control unit compares the supply power with the demand power, and if the supply power is greater than the demand power, the output to the power conversion circuit is such that a surplus of the supply power is supplied to the power auxiliary device. And when the supply power is less than the demand power, the power conversion circuit is configured to execute the input process so that the shortage of the supply power is compensated by the power from the power auxiliary device. . The control unit is configured to determine whether or not an event that causes a hunting phenomenon has occurred in the power conversion circuit, and to execute hunting suppression control when determining that the event has occurred. In the hunting suppression control, the control unit is configured to give the instruction to the power conversion circuit so that a difference between the supplied power and the demand power becomes large.

1 is a schematic overall configuration diagram of a power supply system according to a first embodiment. It is a block diagram of the control part of the power converter device in a 1st embodiment. It is a figure which shows the electric power input / output state in charge fixed control. It is a figure showing the time transition of electric power generation amount, and is a figure for demonstrating the system side hunting phenomenon. It is a figure showing the time transition of electric power generation amount, and is a figure for demonstrating hunting suppression control. It is a figure for demonstrating the 1st implementation example of the hunting suppression control corresponding to charge determination control corresponding to 1st Embodiment. It is a figure for demonstrating the 2nd implementation example of the hunting suppression control corresponding to charge determination control according to 1st Embodiment. It is a figure for demonstrating the cancellation conditions of hunting suppression control concerning 1st Embodiment. It is a figure for demonstrating the cancellation conditions of hunting suppression control concerning 1st Embodiment. It is a figure which shows the electric power input / output state in discharge quantitative control. It is a figure for demonstrating the 1st implementation example of the hunting suppression control corresponding to 1st Embodiment and corresponding to discharge quantitative control. It is a figure for demonstrating the 2nd implementation example of the hunting suppression control corresponding to 1st Embodiment and corresponding to discharge quantitative control. It is a figure which shows the electric power input / output state in system | strain output fixed control. It is a figure for demonstrating the 1st implementation example of the hunting suppression control corresponding to 1st Embodiment and corresponding to system | strain output fixed control. It is a figure for demonstrating the 2nd implementation example of the hunting suppression control corresponding to 1st Embodiment and corresponding to system | strain output fixed control. It is a figure which shows the electric power input / output state in system | strain input fixed control. It is a figure for demonstrating the 1st implementation example of the hunting suppression control corresponding to 1st Embodiment and corresponding to system | strain input fixed control. It is a figure for demonstrating the 2nd implementation example of the hunting suppression control corresponding to 1st Embodiment and corresponding to system | strain input fixed control. It is an operation | movement flowchart of the power converter device which concerns on 1st Embodiment. It is a figure which concerns on 2nd Embodiment and shows the relationship between the output current of a generator, and generated electric power. It is a figure which concerns on 2nd Embodiment and shows the mode of transmission of an electric current command value. It is a figure for demonstrating the cancellation conditions of hunting suppression control concerning 2nd Embodiment. It is a figure for demonstrating the cancellation conditions of hunting suppression control concerning 2nd Embodiment. It is an operation | movement flowchart of the power converter device which concerns on 2nd Embodiment. It is a schematic whole block diagram of the electric power supply system which concerns on 3rd Embodiment. It is a figure which concerns on 3rd Embodiment and shows the electric power input / output state in charge fixed quantity control. It is a figure which concerns on 3rd Embodiment and shows the electric power input / output state in discharge quantitative control. It is a figure which concerns on 3rd Embodiment and shows the electric power input / output state in system | strain output fixed control. It is a figure which concerns on 3rd Embodiment and shows the electric power input / output state in system | strain input fixed control. It is an operation | movement flowchart of the power converter device which concerns on 3rd Embodiment. It is a partial deformation | transformation block diagram of an electric power supply system. It is a partial deformation | transformation block diagram of an electric power supply system.

The power conversion device 2 according to the first embodiment of the present invention includes a power conversion circuit 20 and a control unit 23. The power conversion circuit 20 includes a power receiving function that receives power from the power supply device, a power transmission function that supplies power to the power demand device, an output process that supplies power to the power auxiliary device, and an input process that acquires power from the power auxiliary device. And adjusting at least one of an input / output selection function for selectively executing and supply power that is power received from the power supply device and demand power that is power supplied to the power demanding device in accordance with an instruction from the control unit 23 An adjustment function. The control unit 23 compares the supplied power with the demand power, and if the supplied power is greater than the demand power, causes the power conversion circuit 20 to execute an output process so that a surplus of the supplied power is supplied to the power auxiliary device. Is less than the demand power, the power conversion circuit 20 is configured to execute the input process so that the shortage of the supplied power is compensated by the power from the power auxiliary device. The control unit 23 is configured to determine whether or not an event that causes a hunting phenomenon has occurred in the power conversion circuit 20, and to execute hunting suppression control when determining that an event has occurred. In the hunting suppression control, the control unit 23 is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

In the power conversion device 2 of the second form according to the present invention, in the first form, the instruction is a target value of demand power. The power conversion circuit 20 is configured to adjust the demand power to the target value when receiving the target value from the control unit 23. The control unit 23 is configured to execute normal control for setting the target value to a default value until it is determined that an event has occurred. In the hunting suppression control, the control unit 23 is configured to set the target value to a value different from the default value.

In the power conversion device 2 according to the third embodiment of the present invention, the power supply device is the power generation device 4 in the second embodiment. The power demand device is one of the power storage device 3 and the power system 5, and the power auxiliary device is the other of the power storage device 3 and the power system 5.

In the power conversion device 2 according to the fourth aspect of the present invention, in the first aspect, the power supply device includes a power generation device 4 and a power supply device. The supplied power is the sum of the generated power that is the power supplied from the power generation device 4 and the power supply power that is the power obtained from the power supply device. The instruction is a target value of power supply power. The power conversion circuit 20 is configured to adjust the power supply power to the target value when receiving the target value. The control unit 23 is configured to execute normal control for setting the target value to a default value until it is determined that an event has occurred. In the hunting suppression control, the control unit 23 is configured to set the target value to a value different from the default value.

In the power conversion device 2 of the fifth aspect according to the present invention, in the fourth aspect, the power supply device is one of the power storage device 3 and the power system 5, and the power auxiliary device is the power storage device 3 and the power system 5. And the other.

In the power conversion device 2 according to the sixth embodiment of the present invention, the power supply device includes the power generation device 4 in the first embodiment. The supplied power includes generated power that is power obtained from the power generation device 4. The instruction is a target value of generated power. When receiving the target value, the power conversion circuit 20 is configured to control the power generation device 4 so that the generated power becomes the target value. The control unit 23 is configured to execute normal control for setting the target value to a predetermined value until it is determined that an event has occurred. The controller 23 is configured to set the target value to a value different from the default value in the hunting suppression control.

In the power conversion device 2 according to the seventh aspect of the present invention, in the sixth aspect, the power generation device 4 is a solar cell. The power conversion circuit 20 is configured to adjust the generated power by changing the operating point of the solar cell in accordance with an instruction.

In the power conversion device 2 according to the eighth aspect of the present invention, in the seventh aspect, the default value is a value corresponding to the maximum power of the solar cell.

In the power conversion device 2 of the ninth aspect according to the present invention, in any one of the sixth to eighth aspects, the power demand device is one of the power storage device 3 and the power system 5, and The device is the other of power storage device 3 and power system 5.

In the power conversion device 2 of the tenth aspect according to the present invention, in any one of the sixth to eighth aspects, the power supply device further includes a power supply device. The supplied power is the sum of the generated power that is the power supplied from the power generation device 4 and the power supply power that is the power obtained from the power supply device. The power supply device is one of the power storage device 3 and the power system 5, and the power auxiliary device is the other of the power storage device 3 and the power system 5.

In the power conversion device 2 according to the eleventh aspect of the present invention, in the first aspect, the power conversion circuit 20 has a second input / output selection function for selectively executing the second output process and the second input process. Have. In the second output process, the power conversion circuit 20 is configured to increase the power demand by using the second power auxiliary device as a part of the power demand device by supplying power to the second power auxiliary device. In the second input process, the power conversion circuit 20 is configured to increase the supply power by using the second power auxiliary device as a part of the power supply device by acquiring power from the second power auxiliary device. The hunting suppression control includes first hunting suppression control that causes the power conversion circuit 20 to execute the second output process, and second hunting suppression control that causes the power conversion circuit 20 to execute the second input process. When it is determined that an event has occurred, the control unit 23 is configured to execute either the first hunting suppression control or the second hunting suppression control so that the difference between the supplied power and the demand power becomes large.

In the twelfth mode power conversion device 2 according to the present invention, in the eleventh mode, the second power auxiliary device is the second power storage device 3a. The power conversion circuit 20 is configured to charge the second power storage device 3a in the second output process and to discharge the second power storage device 3a in the second input process.

In the power conversion device 2 according to the thirteenth aspect of the present invention, in the twelfth aspect, when the control unit 23 determines that an event has occurred, the remaining power of the second power storage device 3a is compared with a predetermined value. Configured to do. The control unit 23 is configured to execute the first hunting suppression control if the remaining amount is less than the predetermined value, and to execute the second hunting suppression control if the remaining amount is equal to or greater than the predetermined value.

In the power conversion device 2 according to the fourteenth aspect of the present invention, in any one of the eleventh to thirteenth aspects, the power supply device is the power generation device 4. The power demand device is one of the power storage device 3 and the power system 5, and the power auxiliary device is the other of the power storage device 3 and the power system 5.

In the power conversion device 2 of the fifteenth aspect according to the present invention, in any one of the eleventh to thirteenth aspects, the power supply device includes a power generation device 4 and a power supply device. The power supply device is one of the power storage device 3 and the power system 5, and the power auxiliary device is the other of the power storage device 3 and the power system 5.

In the power conversion device 2 of the sixteenth aspect according to the present invention, in any one of the first to fifteenth aspects, the control unit 23 determines that the difference between the supplied power and the demand power is during execution of the hunting suppression control. When the release condition is satisfied, the hunting suppression control is configured to end.

In the power conversion device 2 according to the seventeenth aspect of the present invention, in the sixteenth aspect, the cancellation condition is that the absolute value of the difference between the supply power and the demand power is equal to or less than a predetermined threshold, or the supply power This is that a state where the absolute value of the difference from the demand power is equal to or less than a predetermined threshold has continued for a predetermined time. The predetermined threshold is smaller than the range of change in the difference between the supplied power and the demand power due to the execution of the hunting suppression control.

In the power conversion device 2 according to the eighteenth aspect of the present invention, in the sixteenth aspect, the cancellation condition is that the state where the difference between the supplied power and the demand power is positive or negative continues for a predetermined time.

In the power conversion device 2 according to the nineteenth aspect of the present invention, in the second or third aspect, the control unit 23 satisfies the release condition when the difference between the supplied power and the predetermined value is during execution of the hunting suppression control. In the case, the hunting suppression control is configured to end. The release condition is that the absolute value of the difference is equal to or greater than the threshold, the state where the absolute value of the difference is equal to or greater than the threshold continues for a predetermined first time, or the state where the difference is positive or negative is the predetermined second. One of the things that lasted for hours.

In the power conversion device 2 of the twentieth aspect according to the present invention, in the fourth or fifth aspect, the control unit 23 calculates the total value of the generated power and the predetermined value and the demand power during execution of the hunting suppression control. When the difference between the two satisfies the release condition, the hunting suppression control is configured to end. The release condition is that the absolute value of the difference is equal to or greater than the threshold, the state where the absolute value of the difference is equal to or greater than the threshold continues for a predetermined first time, or the state where the difference is positive or negative is the predetermined second. One of the things that lasted for hours.

In the power conversion device 2 of the twenty-first form according to the present invention, in the ninth form, when the control unit 23 performs the hunting suppression control and the difference between the demand power and the predetermined value satisfies the release condition, It is comprised so that hunting suppression control may be complete | finished. The release condition is that the absolute value of the difference is equal to or greater than the threshold, the state where the absolute value of the difference is equal to or greater than the threshold continues for a predetermined first time, or the state where the difference is positive or negative is the predetermined second. One of the things that lasted for hours.

In the power conversion device 2 of the twenty-second aspect according to the present invention, in the tenth aspect, the control unit 23 determines that the difference between the total value of the power supply power and the predetermined value and the power for demand is during execution of the hunting suppression control. When the release condition is satisfied, the hunting suppression control is configured to end. The release condition is that the absolute value of the difference is greater than or equal to a threshold, the state where the absolute value of the difference is greater than or equal to the threshold continues for a predetermined first time, or the state where the difference is positive or negative is predetermined. One of the things that lasted for the second time.

In the power conversion device 2 of the twenty-third form according to the present invention, in any one of the eleventh to fifteenth forms, the power conversion circuit 2 increases the demand power from the first predetermined value in the second output process. Configured as follows. The control unit 23 is configured to end the first hunting suppression control when the difference between the supplied power and the first predetermined value satisfies the first release condition during the execution of the first hunting suppression control. The first release condition is that the first absolute value of the difference between the supplied power and the first predetermined value is equal to or greater than the first threshold, and the state where the first absolute value is equal to or greater than the first threshold continues for a predetermined first time. Or a state in which the difference between the supplied power and the first predetermined value is positive or negative has continued for a predetermined second time.

In the power conversion device 2 of the twenty-fourth aspect according to the present invention, in any one of the eleventh to fifteenth and twenty-third aspects, the power conversion circuit 2 supplies the second predetermined power supply in the second input process. Configured to increase from the value. The control unit 23 is configured to end the second hunting suppression control when the difference between the demand power and the second predetermined value satisfies the second release condition during the execution of the second hunting suppression control. The second release condition is that the second absolute value of the difference between the demand power and the second predetermined value is equal to or greater than the second threshold, and the state where the second absolute value is equal to or greater than the second threshold continues for a predetermined third time. Or a state in which the difference between the demand power and the second predetermined value is positive or negative has continued for a predetermined fourth time.

In the power conversion device 2 of the twenty-fifth aspect according to the present invention, in any one of the first to twenty-fourth aspects, the control unit 23 switches between input processing and output processing during execution of hunting suppression control. It is determined whether or not the operation has been performed a predetermined number of times, and when it is determined that the switching operation has been performed a predetermined number of times, the hunting suppression control is configured to end.

In the power conversion device 2 of the twenty-sixth aspect according to the present invention, in any one of the first to twenty-fifth aspects, the control unit 23 causes the power conversion circuit 20 to perform a switching operation between output processing and input processing. It is configured to determine that an event has occurred when a predetermined number of times have been performed in time.

In the power conversion device 2 according to the twenty-seventh aspect of the present invention, in any one of the first to twenty-sixth aspects, the control unit 23 determines that the absolute value of the difference between the supplied power and the demand power is equal to or less than a determination value. It is determined whether or not there is an event, and when it is determined that the absolute value is equal to or less than the determination value, it is determined that an event has occurred.

In the power conversion device 2 of the twenty-eighth aspect according to the present invention, in any one of the first to twenty-sixth aspects, the control unit 23 determines that the absolute value of the difference between the supplied power and the demand power is equal to or less than a determination value. It is configured to determine whether or not a certain state has continued for the determination time, and to determine that an event has occurred when it is determined that the state has continued for the determination time.

Hereinafter, an example of an embodiment of the present invention will be specifically described with reference to the drawings. In each of the drawings to be referred to, the same part is denoted by the same reference numeral, and redundant description regarding the same part is omitted in principle. In this specification, for simplification of description, a symbol or reference that refers to information, signal, physical quantity, state quantity, member, or the like is written to indicate information, signal, physical quantity, state quantity or Names of members and the like may be omitted or abbreviated.

(First embodiment)
1. Configuration of Power Converter 2 of First Embodiment The power converter 2 of the present embodiment is different from the power converter 2 of the first to fifth, sixteenth to twentieth and twenty-fifth to twenty-eighth embodiments of the present invention. Related.

Hereinafter, a first embodiment of the present invention will be described. FIG. 1 is a schematic overall configuration diagram of a power supply system 1 according to the first embodiment, which can also be referred to as a storage battery system. The power supply system 1 includes all or part of the blocks shown in FIG. For example, the power supply system 1 includes at least a power conversion device 2, a power storage device 3, a power generation device 4, a display unit 9, and an operation unit 10. The display unit 9 and the operation unit 10 may be components of the power conversion device 2.

The power supply system 1 is connected to, for example, a DC load 8 and a system load 7.

The power storage device 3 is provided with a battery unit (not shown) composed of one or more secondary batteries. The secondary battery forming the battery unit of the power storage device 3 is any type of secondary battery, such as a lithium ion battery or a nickel metal hydride battery. In the present embodiment, discharging and charging means discharging and charging of the power storage device 3 (more specifically, discharging and charging of each secondary battery in the battery unit of the power storage device 3) unless otherwise specified.

The power conversion device 2 includes a power conversion circuit 20 and a control unit 23.

The power conversion circuit 20 includes a power receiving function that receives power from the power supply device, a power transmission function that supplies power to the power demand device, an output process that supplies power to the power auxiliary device, and an input process that acquires power from the power auxiliary device. And an input / output selection function for selectively executing.

Furthermore, the power conversion circuit 20 has an adjustment function for adjusting at least one of supply power that is power received from the power supply device and demand power that is power supplied to the power demand device in accordance with an instruction from the control unit 23. Have. It can be said that the supplied power is power that can be supplied from the power supply apparatus to the power demand apparatus. Moreover, it can be said that demand power is the electric power requested | required from an electric power demand apparatus. Hereinafter, the magnitude of the supplied power is referred to as the supplied power amount. The amount of power supplied is equal to the total amount of power supplied for 1 second, for example. The magnitude of demand power is called demand power. The amount of power demand is equal to the total amount of power demand for one second, for example.

The control unit 23 is configured to execute quantitative control. In the quantitative control, the control unit 23 compares the supplied power with the demand power, and if the supplied power is larger than the demand power, performs an output process on the power conversion circuit 20 so that a surplus of the supplied power is supplied to the power auxiliary device. If the supply power is less than the demand power, the power conversion circuit 20 is configured to execute the input process so that the shortage of the supply power is compensated by the power from the power auxiliary device.

Quantitative control includes charge quantitative control, discharge quantitative control, system output quantitative control, and system input quantitative control.

In charge quantitative control, the power generation device 4 is used as a power supply device, the power storage device 3 is used as a power demand device, and the power system 5 is used as a power auxiliary device.

In the discharge quantitative control, the power generation device 4 and the power storage device 3 are used as a power supply device, the DC load 8 is used as a power demand device, and the power system 5 is used as a power auxiliary device.

In the grid output quantitative control, the power generation device 4 is used as a power supply device, the power system 5 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device.

In the grid input quantitative control, the power generation device 4 and the power system 5 are used as a power supply device, the DC load 8 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device.

The control unit 23 is configured to selectively execute charge quantitative control, discharge quantitative control, system output quantitative control, and system input quantitative control.

Control unit 23 determines whether an event has occurred that hunting occurs in the power conversion circuit 20, when determining that an event has occurred hunting suppression control _{_{_{CNT 1 (CNT 1A, CNT 1B}}} , CNT 1C, CNT 1D), Configured to perform. In the hunting suppression control CNT ₁ , the control unit 23 is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

For example, the control unit 23 includes a comparison unit 231, a determination unit 232, and an instruction unit 233 as shown in FIG.

The comparison unit 231 is configured to compare the supplied power and the demand power, and to give the comparison result to the instruction unit 233.

The determination unit 232 is configured to determine whether or not an event that causes a hunting phenomenon has occurred in the power conversion circuit 20 and to give the determination result to the instruction unit 233. Further, the determination unit 232 is configured to determine whether or not a release condition described later is satisfied.

If the comparison result indicates that the supplied power is greater than the demand power, the instruction unit 233 causes the power conversion circuit 20 to execute the output process so that the surplus of the supplied power is supplied to the power auxiliary device. Composed.

If the comparison result indicates that the supplied power is less than the demand power, the instructing unit 233 causes the power conversion circuit 20 to perform input processing so that the shortage of the supplied power is compensated by the power from the power auxiliary device. .

The instruction unit 233 is configured to execute the hunting suppression control CNT ₁ if the determination result indicates that an event has occurred. In the hunting suppression control CNT ₁ , the instruction unit 233 is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

The power conversion circuit 20 includes a power terminal (external power terminal) _TB1 and a power terminal (internal power terminal) _TB2 , and a (first) power conversion unit 21B for the power storage device connected to the power storage device 3, The power terminal (external power terminal) T _G1 and the power terminal (internal power terminal) T _G2 , the (second) power conversion unit 21G for the power generator connected to the power generator 4, and the power terminal (external power terminal) ) Having T _S1 and a power terminal (internal power terminal) T _S2 , and a (third) power conversion unit 21S for the system connected to the power system 5 and a

power connection unit

21B, 21G and 21S in the middle Wiring 22.

Intermediate wire 22 includes a (first) internal power terminal T _B2 of the first power conversion unit 21B, the second power conversion unit 21G (second) and the internal power terminal T _G2, the third power conversion unit 21S (the 3) Connected to the internal power terminal T _S2 .

The power storage device 3 is connected to the power conversion unit 21B at the (first) external power terminal T _{B1 and} can output its own discharge power to the power conversion unit 21B and supply charging power from the power conversion unit 21B. When you receive it, it will be charged. Below, the magnitude | size of discharge electric power is called discharge electric energy. The amount of discharge power is equal to the total amount of discharge power for one second, for example. The magnitude of the charging power is referred to as the charging power amount. The amount of charging power is equal to the total amount of demand power for one second, for example.

The power generation device 4 is a power generation device that performs power generation based on arbitrary energy and outputs generated power, and examples of the energy include natural energy (sunlight, wind power, hydropower, geothermal heat, and the like). The generated power depends on natural energy. Therefore, the generated power is not constant and can change with time. Below, the magnitude of the generated power is referred to as the amount of generated power. The amount of generated power is equal to the total amount of generated power for one second, for example.

Here, it is assumed that the power generation device 4 is a solar power generation device that generates power based on sunlight and outputs generated power. The power generator 4 is connected to the power converter 21G at the (second) external power terminal T _G1 , and the generated power of the power generator 4 is output to the power converter 21G.

The power system 5 is connected to a commercial power source 6 that generates and outputs commercial AC power, and transmits the commercial AC power. The power system 5 is connected to the power conversion unit 21S at the (third) external power terminal T _S1, and power transmission and reception between the power conversion unit 21S and the power system 5 are performed via the power terminal T _S1 . That is, the power system 5 supplies input power to the power conversion circuit 20 and receives output power from the power conversion circuit 20. Hereinafter, the magnitude of input power is referred to as input power amount. The input power amount is equal to, for example, the total amount of input power for one second. The magnitude of output power is referred to as output power amount. The output power amount is equal to the total amount of output power for one second, for example.

The power terminals T _B2 , T _G2, and T _S2 are commonly connected in the power conversion circuit 20 by the intermediate wiring 22.

The system load 7 and the DC load 8 are, for example, industrial equipment or electrical appliances in factories, stores, buildings, or general houses where the power supply system 1 is introduced. The system load 7 is connected to the power terminal T _S1 and the power system 5, and the DC load 8 is connected to the intermediate wiring 22. Although all or part of the power output from the power conversion circuit 20 to the power system 5 may be consumed by the system load 7, here, the power from the power conversion circuit 20 to the system load 7 is converted into power conversion. It is considered that it is a part of the output power from the circuit 20 to the power system 5 (that is, the power consumption of the system load 7 is not related to the essence of the present invention, so the following description ignores the presence of the system load 7). ). A power conversion unit may be provided between the DC load 8 and the intermediate wiring 22.

The power conversion circuit 20 performs power transmission and power reception among the power storage device 3, the power generation device 4, and the power system 5 under the control of the control unit 23, and performs necessary power conversion at the time of power transmission and power reception.

Specifically, power conversion unit 21B converts the DC discharge power received from power storage device 3 via power terminal (external power terminal) _TB1 to other DC power, and converts the other DC power to power terminal. (internal power terminal) and the discharge power conversion output from T _B2, the power terminals (internal power terminal) of the DC power received via the T _B2 is converted into another DC power said other DC power power terminal ( It is possible to execute power conversion for charging that is output to the power storage device 3 as charging power via the external power terminal T _B1 .

That is, the power converter 21B receives power from the power storage device 3 as a power supply device, a power transmission function that supplies power to the power storage device 3 as a power demand device, and supplies power to the power storage device 3 as a power auxiliary device. An input / output selection function for selectively executing an output process to be performed and an input process for acquiring power from the power storage device 3 as a power auxiliary device.

In addition, the power conversion unit 21B, in response to an instruction from the control unit 23, supplies power (discharge power) that is power received from the power storage device 3 as a power supply device and power supplied to the power storage device 3 as a power demand device. It has an adjustment function to adjust the demand power (charging power).

That is, the power conversion unit 21B, in response to an instruction from the control unit 23, supplies power (discharged power) that is the amount of power received from the power storage device 3 as the power supply device and the power storage device 3 as the power demand device. The amount of power demand (charge power amount) that is the amount of power supplied to the battery is adjusted.

Therefore, when receiving the target value of the discharge power (discharge power amount) from the control unit 23, the power conversion unit 21B adjusts the discharge power (discharge power amount) to the target value. Further, upon receiving the target value of the charging power (charging power amount) from the control unit 23, the power conversion unit 21B adjusts the charging power (charging power amount) to the target value.

The power output from the power terminal _TB2 by the power conversion for discharge is sent to the DC load 8 through the intermediate wiring 22, or is sent to the power system 5 through the intermediate wiring 22 and the power conversion unit 21S.

In charge power conversion, the DC power by the power conversion unit 21B receives via a power terminal T _B2, the power based on the power generated by the power conversion unit 21G and the intermediate wiring 22 power generator is supplied via the 4, or the power The power is based on the commercial AC power supplied from the power system 5 supplied via the converter 21S and the intermediate wiring 22, or a combination thereof.

The power conversion unit 21G converts the generated DC power received from the power generation device 4 through the power terminal T _G1 into another DC power and outputs the other DC power from the power terminal T _G2. It is feasible.

That is, the power conversion unit 21G has a power receiving function of receiving power from the power generation device 4 as a power supply device.

Further, the power conversion unit 21G has an adjustment function of adjusting supply power (generated power) that is power received from the power generation device 4 as a power supply device in accordance with an instruction from the control unit 23.

That is, the power conversion unit 21G adjusts the supply power amount (generated power amount), which is the amount of power received from the power generation device 4 as the power supply device, in accordance with an instruction from the control unit 23.

Therefore, when receiving the target value of the generated power (generated power amount) from the control unit 23, the power conversion unit 21G adjusts the generated power (generated power amount) to the target value.

The power output from the power terminal _TG2 by the power conversion for power generation is sent to the DC load 8 through the intermediate wiring 22, sent to the power system 5 through the intermediate wiring 22 and the power conversion unit 21S, or intermediate It is sent to the power storage device 3 through the wiring 22 and the power conversion unit 21B.

The power conversion unit 21S converts the commercial AC power received from the power system 5 through the power terminal T _S1 into DC power and outputs the DC power from the power terminal T _S2. It is possible to perform power conversion for system output that converts the DC power received via _S2 into AC power and outputs the AC power to the power system 5 via the power terminal T _S1 .

That is, the power conversion unit 21S receives power from the power system 5 as a power supply device, a power transmission function that supplies power to the power system 5 as a power demand device, and supplies power to the power system 5 as a power auxiliary device. An input / output selection function for selectively executing output processing to be performed and input processing for acquiring power from the power system 5 as a power auxiliary device.

In addition, the power conversion unit 21S, in response to an instruction from the control unit 23, supplies power (input power) that is power received from the power system 5 as a power supply device and power supplied to the power system 5 as a power demand device. It has an adjustment function for adjusting the demand power (output power).

That is, the power conversion unit 21S supplies the supply power amount (input power amount) that is the power received from the power system 5 as the power supply device and the power system 5 as the power demand device according to the instruction from the control unit 23. It has an adjustment function for adjusting the amount of demand power (output power amount) that is the power to be generated.

Therefore, when receiving the target value of the input power (input power amount) from the control unit 23, the power conversion unit 21S adjusts the input power (input power amount) to the target value. Further, when receiving the target value of the output power (output power amount) from the control unit 23, the power conversion unit 21S adjusts the output power (output power amount) to the target value.

The power output from the power terminal T _S2 by the power conversion for system input is sent to the DC load 8 via the intermediate wiring 22 or sent to the power storage device 3 via the intermediate wiring 22 and the power conversion unit 21B.

In the power conversion for system output, the DC power received by the power conversion unit 21S via the power terminal T _S2 is based on the discharge power of the power storage device 3 supplied from the power storage device 3 via the power conversion unit 21B and the intermediate wiring 22. DC power, or DC power based on the generated power of the power generation device 4 supplied from the power generation device 4 via the power conversion unit 21G and the intermediate wiring 22, or a combination thereof.

The control unit 23 acquires input / output power information representing a voltage value, a current value, and a power amount in each unit of the power conversion circuit 20 using various sensors.

For example, the power conversion device 2 includes a plurality of current sensors (not shown) that measure values I _B , I _G , and I _S of currents flowing through the external power terminals T _B1 , T _G1 , and T _S1 , and an internal power terminal. _And a plurality of current sensors (not shown) for measuring values I _BINT , I _GINT , and I _SINT of currents flowing through T _B2 , T _G2 , and T _S2 , respectively.

In addition, the power converter 2 includes a plurality of voltage sensors (not shown) that measure the voltage values V _B , V _G , and V _S of the external power terminals T _B1 , T _G1 , and T _S1 , and an internal power terminal. And a voltage sensor (not shown) for measuring the value V _INT of the voltages T _B2 , T _G2 , and T _S2 (that is, the voltage of the intermediate wiring 22).

Specifically, the control unit 23 uses current sensors to measure current values (current values) I _B and I flowing through the power terminals T _B1 , T _G1 , T _S1 , T _B2 , T _G2 , and T _S2. _G , I _S , I _BINT , I _GINT , and I _SINT are acquired individually, and voltage values (voltage values) V _B and V _G applied to the power terminals T _B1 , T _G1 , and T _S1 using the voltage sensor are obtained. , V _S is acquired individually.

The control unit 23 uses the voltage sensor, acquires the power terminal T _B2, the value of the common voltage applied to the T _G2 and T _S2 (voltage value) V _INT.

The input / output power information includes current values I _B , I _G , I _S , I _BINT , I _GINT and I _SINT , and voltage values V _B , V _G , V _S and V _INT , and the following formulas (1a) to (1f ) _Can also include power magnitudes (power quantities) P _B , P _G , P _S , P _BINT , P _GINT, and P _SINT .

I _B , V _B, and P _B are output to the power storage device 3 from the current value, voltage value, and power amount of the discharge power of the power storage device 3 input from the power storage device 3 to the power conversion unit 21B, or from the power conversion unit 21B, respectively. Current value, voltage value, and electric energy in the charging power of the power storage device 3 to be performed.

I _G , V _G, and P _G are a current value, a voltage value, and an electric energy in the generated power of the power generation device 4 input from the power generation device 4 to the power conversion unit 21G, respectively.

I _S , V _S, and P _S are current values, voltage values, and amounts of electric power in commercial AC power input from the power system 5 to the power conversion unit 21S, or AC output from the power conversion unit 21S to the power system 5, respectively. It is the current value, voltage value, and electric energy in electric power.

I _BINT and V _INT are current values and voltage values corresponding to I _B and V _B before or after power conversion in the power conversion unit 21B.

I _GINT and V _INT are current values and voltage values after power conversion in the power conversion unit 21G, corresponding to I _G and V _G.

I _SINT and V _INT are current values and voltage values corresponding to I _S and V _S before or after power conversion in the power conversion unit 21S.

The control unit 23 controls the operation of the power conversion circuit 20 including the operation of each power conversion of the

power conversion units

21B, 21G, and 21S based on the input / output power information, and through the control of the operation of the power conversion circuit 20, It controls power transmission and power reception among the power storage device 3, the power generation device 4, and the power system 5.

Further, the control unit 23 can display a desired image on the display unit 9 by controlling the display unit 9 including a liquid crystal display or the like.

The operation unit 10 receives various instructions and information from the operator of the power supply system 1 and transmits the instructions and information to the control unit 23. The operator is, for example, an owner, a user, or a maintenance manager (so-called service man) of the power supply system 1. The operation unit 10 can include a touch panel on the display unit 9.

Note that one or more other power storage devices similar to the power storage device 3 may be further provided in the power supply system 1, and in this case, a power conversion unit for the other one or more power storage devices is added to the power conversion circuit 20. This is preferable (the same applies to other embodiments described later).

One or more other power generation devices similar to the power generation device 4 may be further provided in the power supply system 1, and in this case, a power conversion unit for the other one or more power generation devices is added to the power conversion circuit 20. This is preferable (the same applies to other embodiments described later). The control unit 23 may be formed by a plurality of control units (the same applies to other embodiments described later).

The control unit 23 can execute charge quantitative control, discharge quantitative control, system output quantitative control, and system input quantitative control based on the input / output power information. Hereinafter, the charge quantitative control, the discharge quantitative control, the system output quantitative control, and the system input quantitative control will be described in detail.

2. Contents of each quantitative control (1) Charge quantitative control (1-1) Basic operation First, charge quantitative control will be described. In the charge quantitative control, the control unit 23 controls the power conversion circuit 20 using the generated power of the power generation device 4 so that the power storage device 3 is charged under a constant charge reference condition.

In charge quantitative control, the control unit 23 charges the power storage device 3 using the power generation device 4 and the power system 5. In the charge quantitative control, the power generation device 4 is used as a power supply device, the power storage device 3 is used as a power demand device, and the power system 5 is used as a power auxiliary device. Therefore, in the charging quantitative control, the supplied power is the generated power of the power generation device 4. The demand power is power (charging power) used for charging the power storage device 3.

In charge quantitative control, the control unit 23 (comparison unit 231) compares the generated power (generated power amount) of the power generation device 4 with the charged power (charged power amount) of the power storage device 3.

If the supplied power (generated power) is greater than the demand power (charged power), the control unit 23 (instruction unit 233) supplies the surplus of the supplied power (generated power) to the power system 5 (power auxiliary device). The power conversion circuit 20 is caused to execute output processing (power conversion for system output of the power conversion unit 21S).

Specifically, the control unit 23 (instruction unit 233) gives an instruction (target value of output power) to the power conversion unit 21S so that output power corresponding to the difference between the generated power and the charged power can be obtained. For example, if the supplied power amount is 12 kW · s and the charged power amount is 10 kW · s, 2 kW · s is given to the power conversion unit 21S as the target value of the output power.

If the supplied power (generated power) is less than the demand power (charged power), the controller 23 (instruction unit 233) supplements the shortage of the supplied power (generated power) with the power from the power system 5 (power auxiliary device). Thus, the power conversion circuit 20 is caused to execute input processing (system input power conversion of the power conversion unit 21S).

Specifically, the control unit 23 (instruction unit 233) gives an instruction (target value of input power) to the power conversion unit 21S so that input power corresponding to the difference between the generated power and the charged power can be obtained. For example, if the supplied power amount is 8 kW · s and the charged power amount is 10 kW · s, the control unit 23 gives 2 kW · s to the power conversion unit 21S as the target value of the input power.

In this way, in this charging quantitative control, when the amount of power generated by the power generation device 4 is smaller than the amount of power required for charging the power storage device 3 (charge power amount), the shortage power (shortage power amount) corresponding to the difference between them. ) Is input from the power system 5 to the power conversion circuit 20 and when the amount of power generated by the power generation device 4 is larger than the amount of power required for charging the power storage device 3 (charge power amount), the difference between them The control unit 23 controls the power conversion circuit 20 based on the input / output power information so that the surplus power corresponding to (the amount of surplus power) is output from the power conversion circuit 20 to the power system 5. When considering charge quantitative control, the presence of the DC load 8 is ignored (regardless of the presence or absence of the DC load 8).

The charging reference condition is a condition for designating a charging power amount of the power storage device 3 or a current value and a voltage value depending on the charging power amount, and the control unit 23 can freely determine the charging reference condition. The charging reference condition may be a condition for designating only one of a current value and a voltage value depending on the amount of charging power of the power storage device 3. Here, it is assumed that the charge reference condition specifies that the power storage device 3 is charged with a constant reference power amount for storage (charge / discharge reference power amount) P _BREF .

The control unit 23 can generate a charge command amount P _B ^* that specifies the amount of charge power supplied from the power conversion unit 21B to the power storage device 3 and give the charge command amount P _B ^* to the power conversion unit 21B.

The power conversion unit 21B performs power conversion for charging including control of the voltage value V _B and the current value I _B in order to supply the power storage device 3 with the charging power amount specified by the charging command amount P _B ^* .

The charge command amount P _B ^* may be formed from a voltage command amount and a current command amount that specify the voltage value V _B and the current value I _B.

In the charge quantitative control, the control unit 23 can charge the power storage device 3 with a constant reference power amount P _BREF for storage by substituting the value of the reference power amount P _BREF for storage into the charge command amount P _B ^*. .

Now, for the sake of concrete explanation, it is considered that P _BREF = 10, and the unit of numerical values related to an arbitrary electric energy including a charge command amount is unified to be kW · s (kilowatt · second). Think. Further, for simplification of description, it is assumed that the power loss in the power conversion circuit 20 is zero unless otherwise specified (that is, the power conversion efficiency in each power conversion in the power conversion circuit 20 is assumed to be 100%). To do).

In the charge quantitative control, when P _BREF = 10, the control unit 23 can substitute 10 for the charge command amount P _B ^* .

In this case, for example, as shown in FIG. 3A, if the power generation amount of the power generation device 4 is 6 kW · s, the power generation amount of the power generation device 4 is 10 kW · power required for charging the power storage device 3. Since it is less than s (= P _B ^* ), the control unit 23 controls the power conversion unit 21S so that an insufficient power amount 4 kW · s corresponding to the difference between them is input from the power system 5 to the power conversion circuit 20. To do.

On the other hand, for example, as shown in FIG. 3B, if the amount of power generated by the power generation device 4 is 13 kW · s, the amount of power generated by the power generation device 4 is 10 kW · s required for charging the power storage device 3. Since there are more than (= P _B ^* ), the control unit 23 controls the power conversion unit 21S so that the surplus power amount 3 kW · s corresponding to the difference between them is output from the power conversion circuit 20 to the power system 5. .

In FIG. 4, a solid curve 311 represents a time transition of the amount of power generated by the power generation device 4, and timing t _A1 corresponds to the state of FIG. 3A, and timing t _A2 corresponds to the state of FIG. .

As described above, in the charge quantitative control, the generated power of the power generation device 4 is used while absorbing the shortage or surplus of the generated power of the power generation device 4 by the power input / output between the power conversion circuit 20 and the power system 5. Thus, the power storage device 3 is charged under a certain charging reference condition.

(1-2) System-side Hunting Phenomenon However, in charge quantification control, as shown in FIG. 3 (c), when the power generation amount of the power generation device 4 has a value in the vicinity of the power storage reference power P _BREF , The input / output switching of power between the power conversion circuit 20 and the power system 5 is repeatedly generated in a relatively short period due to the transition between the shortage state and the surplus state of the generated power (see also FIG. 4). Such switching at the time of execution of charge quantitative control is called a system-side hunting phenomenon.

In other words, the hunting phenomenon in charge quantitative control is a system-side hunting phenomenon in which the power conversion circuit 20 alternately repeats output processing (system output power conversion) and input processing (system input power conversion) in a relatively short time. It is.

If the hunting phenomenon on the system side occurs, the power system 5 may become unstable. In particular, when a large number of devices into which the power conversion device 2, the power storage device 3, and the power generation device 4 are connected to the power system 5, when the system-side hunting phenomenon occurs in each device, the stability of the power system 5 May be impaired.

(1-3) System side hunting detection processing HD _1A
During the charge quantitative control execution period, the control unit 23 can detect the occurrence of the system-side hunting phenomenon by performing the system-side hunting detection process HD _1A based on the input / output power information.

In the system-side hunting detection process HD _1A , the control unit 23 switches the input / output of power between the power conversion unit 21S and the power system 5 for a predetermined time based on the current value I _S or I _SINT included in the input / output power information. When a predetermined number of times is detected, the system side hunting detection determination is made.

In other words, the control unit 23 (determination unit 232) causes the power conversion circuit 20 to perform a switching operation between the output process (system power conversion) and the input process (system input power conversion) a predetermined number of times within a predetermined time. The event (ie, the occurrence of a hunting phenomenon in the power conversion circuit 20) is determined to occur.

The predetermined number of times may be any number of 1 or more, but 2 or more is desirable. The system-side hunting detection determination means that it is determined that the system-side hunting phenomenon is currently occurring.

(1-4) System side hunting prediction processing HP _1A
Further, during the charge quantitative control execution period, the control unit 23 may predict the occurrence of the system-side hunting phenomenon by performing the system-side hunting prediction process HP _1A based on the input / output power information (that is, the future It is also possible to predict whether a system-side hunting phenomenon is likely to occur).

For example, in the system-side hunting prediction process HP _1A , the control unit 23 generates power based on the current value I _G and the voltage value V _G (that is, based on the generated power amount P _G ) or based on the current value I _GINT and the voltage value V _INT. A charging power amount P _B ′ corresponding to the power amount P _G is obtained, and the charging power amount P _B ′ is compared with the storage power reference power amount P _BREF defined by the charging reference condition. Then, when the absolute value | P _B '−P _BREF | of the difference is equal to or less than a predetermined positive threshold value TH _1A , or the absolute value | P _B ' −P _BREF | _When a state of _1A or less is continuously observed for a predetermined time or more, the system side hunting prediction judgment is made.

The system-side hunting prediction determination means that it is determined that a system-side hunting phenomenon is likely to occur in the near future. The corresponding charge power amount P _B 'in generated power quantity P _G, refers to the charging electric energy for power storage device 3 based on the generated power quantity P _G of the generator 4, the

power conversion unit

21G and 21B power conversion efficiency and product The charging power amount P _B ′ can be obtained using “I _G × V _G ” or using the power conversion efficiency and the product “I _GINT × V _INT ” of the power conversion unit 21B. Assuming zero power loss of the

power converter

21G and 21B, a P _B '= P _G.

That is, the control unit 23 (determination unit 232) determines the absolute value | P _B '−P _BREF | of the difference between the supplied power (charging power amount P _B ') and the demand power (storage power reference amount P _BREF ). It determines whether less than the value (threshold value TH _1A), the absolute value | configured to determine that an event has occurred when is equal to or less than the determination value TH _1A | P _B '-P _BREF .

Note that the control unit 23 (determination unit 232) determines the absolute value | P _B '−P _BREF | of the difference between the supplied power (charging power amount P _B ′) and the demand power (storage power reference amount P _BREF ). It is configured to determine whether or not a state that is equal to or less than a value (threshold value TH _1A ) has continued for a determination time (the predetermined time described above), and to determine that an event has occurred when it is determined that the state has continued for the determination time It may be.

(1-5) Hunting suppression control CNT _1A
When the system-side hunting detection determination or the system-side hunting prediction determination is made during the charge quantitative control execution period, the control unit 23 sets the charge power amount of the power storage device 3 to the power storage reference power amount P according to the charge reference condition. Hunting suppression control CNT _1A changed from _BREF is executed.

In the hunting suppression control CNT _1A , by changing the charging power amount, the absolute value of the input / output power amount between the power conversion circuit 20 and the power system 5 is increased, thereby suppressing the system-side hunting phenomenon. The input / output power amount between the power conversion circuit 20 and the power system 5 indicates the input power amount from the power system 5 to the power conversion circuit 20 or the output power amount from the power conversion circuit 20 to the power system 5. The timing at which the system-side hunting detection determination or the system-side hunting prediction determination is performed is also referred to as a system-side hunting recognition timing. The control unit 23 can start the suppression control CNT _1A from the system-side hunting recognition timing (the same applies to hunting suppression control CNT _1B described later). The suppression control CNT _1A is a control performed in the charge quantitative control, and the content of the charge quantitative control is modified during the execution period of the suppression control CNT _1A .

That is, the control unit 23 (instruction unit 233) is configured to execute the hunting suppression control CNT _1A when it is determined that an event has occurred during the execution period of the charge quantitative control. In the hunting suppression control CNT _1A , the control unit 23 (instruction unit 233) is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

A first implementation example of the suppression control CNT _1A will be described. Before the system-side hunting recognition timing, as described above, the control unit 23 substitutes the power storage reference power amount P _BREF for the charge command amount P _B ^* , whereby the charge power amount of the power storage device 3 becomes the power storage reference power amount. It corresponds to the electric energy P _BREF (= 10) (see FIGS. 3A, 3B, and 3C).

However, when the system-side hunting detection determination or the system-side hunting prediction determination is made, in the first implementation example of the suppression control CNT _1A , the control unit 23 stores the charge command amount P _B ^* by a predetermined amount ΔP _B ^* for power storage. Increase or decrease from the reference power amount P _BREF (that is, change the charge command amount P _B ^* with reference to before the system-side hunting recognition timing). Here, “ΔP _B ^* > 0”. The predetermined amount ΔP _B ^* may be an amount (for example, the product of P _BREF and the coefficient k) that depends on the reference power amount P _BREF for power storage.

That is, the control unit 23 (instruction unit 233) is configured to execute normal control for setting the target value to a predetermined value (storage power reference amount P _BREF ) until it is determined that an event has occurred. In the hunting suppression control CNT _1A , the control unit 23 is configured to set the target value to a value (P _BREF ± ΔP _B ^* ) different from a predetermined value (storage power reference power amount P _BREF ).

Thus, in the first implementation example, the control unit 23 (instruction unit 233) increases or decreases the charging power so that the difference between the generated power and the charging power becomes large.

FIG. 5 shows an example when the charge command amount P _B ^* is decreased. A broken broken line 312 represents a time transition of the charge command amount P _B ^* , and a timing t _A3 is a system-side hunting recognition timing.

FIG. _6A corresponds to immediately after the timing t _A3 , when the charge command amount P _B ^* is reduced to 8 by the suppression control CNT _1A when the generated power amount of the power generation device 4 is 10 kW · s. Indicates the power input / output state. Here, the control unit 23 sets the target value to 8 (= P _BREF −ΔP _B ^* ), which is a value different from the storage reference power amount P _BREF (= 10) (ΔP _B ^* = 2).

In this state, the control unit 23 controls the power conversion unit 21 S so that the surplus power amount 2 kW · s corresponding to the difference between the supplied power and the demand power is output from the power conversion circuit 20 to the power system 5. That is, the absolute value of the input / output power amount between the power conversion circuit 20 and the power system 5 based on the decrease before the decrease due to the decrease in the charged power amount by the suppression control CNT _1A (based on the state of FIG. 3C). Will increase. As a result, the system side hunting phenomenon is appropriately suppressed. The same _applies to the case where the charge command amount P _B ^* is increased from the power storage reference power amount P _BREF .

For example, the control unit 23 may set the target value to 12 (= P _BREF + ΔP _B ^* ), which is a value different from the storage reference power amount P _BREF (= 10) (ΔP _B ^* = 2).

In this state, the control unit 23 controls the power conversion unit 21S so that the insufficient power amount 2 kW · s corresponding to the difference between the supplied power and the demand power is input from the power system 5 to the power conversion circuit 20. As a result, the system side hunting phenomenon is appropriately suppressed.

Thus, in the first implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is a target value of demand power (charging power). That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21B.

A second implementation example of the suppression control CNT _1A will be described. Although not particularly conscious in the above description, the control unit 23 generates a system input / output command amount P _S ^* that specifies the input / output power amount between the power conversion circuit 20 and the power system 5 to generate the power conversion unit 21S. Thus, the input / output power amount can be controlled.

The power conversion unit 21S has a voltage value V _S and a current value I so that power input / output having a power amount matching the system input / output command amount P _S ^* is performed between the power conversion circuit 20 and the power system 5. System input power conversion including _S control or system output power conversion is performed. The command amount P _S ^* may be formed from a voltage command amount and a current command amount that specify the voltage value V _S and the current value I _S.

When mains hunting detection determination or mains hunting prediction judgment is made, the control unit 23 to perform the second implementation of suppression control CNT _1A, based on the pre-system side hunting cognitive timing, system output command amount P _S ^The suppression control CNT _1A is realized by changing ^* by a predetermined amount ΔP _S ^* and assigning the change amount to the change in the amount of charge power of the power storage device 3. Here, “ΔP _S ^* > 0”. The predetermined amount ΔP _S ^* may be an amount (for example, the product of P _BREF and the coefficient k) that depends on the reference power amount P _BREF for power storage.

That is, in the normal control, the control unit 23 (instruction unit 233) instructs the power conversion unit 21S (input power or output power so that input power or output power corresponding to the difference between the generated power and the charging power can be obtained. Target value). On the other hand, in the hunting suppression control CNT _1A , the control unit 23 (instruction unit 233) sets a target value (input power or output power target value) to be given to the power conversion unit 21S to a predetermined value. That is, the control unit 23 causes the power conversion unit 21S to perform either input processing or output processing regardless of the difference between the supplied power (generated power) and the demand power (charged power).

For example, in the state of FIG. 3C, that is, the state in which the amount of power generated by the power generation device 4 and the amount of charge power of the power storage device 3 are both 10 kW · s, the command amount P _S ^* is set as shown in FIG. This corresponds to the state where zero is substituted.

In this state, when the system-side hunting detection determination or the system-side hunting prediction determination is made, the control unit 23 changes the system input / output command amount (target value of output power) P _S ^* from zero to a predetermined value (for example, It is possible to execute the suppression control CNT _1A that is changed to 2) (in this case, it is considered that the state where P _S ^* > 0 corresponds to the power output state from the power conversion unit 21S to the power system 5).

In the second implementation example of the suppression control CNT _1A , the control unit 23 prioritizes the system input / output command amount P _S ^* over the charge command amount P _B ^* , or gives the charge command amount P _B ^* to the power conversion unit 21B. Don't give. In any case, in the suppression control CNT _1A , the control unit 23 charges the power storage device 3 with the surplus power determined by the amount of power generated by the power generation device 4 and the amount of input / output power between the power conversion circuit 20 and the power system 5. The power converter 21B is controlled as described above.

In this case, the amount of generated power is 10 kW · s, but output power of 2 kW · s is supplied to the power system 5. Therefore, the power that can be supplied to the power storage device 3 is 8 kW · s. Therefore, the control unit 23 (instruction unit 233) decreases the charge command amount P _B ^* from the storage reference power amount P _BREF (= 10 kW · s) to 8 kW · s. That is, the control unit 23 gives 8 kW · s as a target value to the power conversion unit 21B. As a result, as shown in FIG. 7, the charging power is directed to the power storage device 3 only for 8 kW · s, which is smaller than the reference power amount P _BREF for power storage. This state is equivalent to the state shown in FIG.

FIG. 7 shows an example in which the command amount P _S ^* is changed so that power output from the power conversion circuit 20 to the power system 5 is performed, but power input from the power system 5 to the power conversion circuit 20 is performed. The command amount P _S ^* may be changed so as to be performed. In this case, the charge power amount of the power storage device 3 increases from 10 kW · s.

For example, the control unit 23 can execute the suppression control CNT _1A that changes the system input / output command amount (target value of input power) P _S ^* from zero to a predetermined value (for example, −2) (here, The state where P _S ^* <0 corresponds to the power input state from the power system 5 to the power conversion unit 21S).

In this case, the amount of generated power is 10 kW · s, but input power of 2 kW · s is supplied from the power system 5. Therefore, the power that can be supplied to the power storage device 3 is 12 kW · s. Therefore, the control unit 23 (instruction unit 233) increases the charge command amount P _B ^* from the power storage reference power amount P _BREF (= 10 kW · s) to 12 kW · s. That is, the control unit 23 gives 12 kW · s as a target value to the power conversion unit 21B. As a result, the power storage device 3 is supplied with charging power of 12 kW · s, which is larger than the power storage reference power amount P _BREF .

Thus, in the second implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is the target value of output power or input power. That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21S.

In the first implementation example of the suppression control CNT _1A , the charge power amount is directly controlled by controlling the charge command amount P _B ^* , whereas in the second implementation example of the suppression control CNT _1A , the system input / output command amount P _The charge power amount is indirectly controlled by controlling _S ^* (by controlling the input / output power amount between the power conversion circuit 20 and the power system 5).

(1-6) cancellation determination processing J _1A corresponding to suppression control CNT _1A
Control unit 23, during the execution period of the suppression control CNT _1A, via the judging success or failure of the predetermined release condition, performing the determining cancellation determination processing J _1A whether to cancel the execution of the suppression control CNT _1A Can do.

For example, in the cancelability determination process J _1A , the control unit 23 performs the above-described operation based on the current value I _G and the voltage value V _G (that is, based on the generated power amount P _G ) or based on the current value I _GINT and the voltage value V _INT. Charge electric energy P _B ′ is obtained, and the charged electric energy P _B ′ is compared with the reference electric energy P _BREF for storage specified in the charging reference condition (as described above, the electric power conversion power loss amount Is considered as zero, P _B ′ = P _G ).

In the determination process J _1A , the control unit 23 determines that the absolute value | P _B '−P _BREF | of the difference is equal to or greater than a predetermined positive threshold TH _2A (see FIG. 8) or the absolute value. When a state in which | P _B '−P _BREF | is _{equal to} or greater than the threshold TH _2A is continuously observed for a predetermined time or more, or a state in which the absolute value | P _B ' −P _BREF | When continuously observed (see FIG. 9; _TL corresponds to a predetermined time in FIG. 9), it is determined that the cancellation condition in the determination process J _1A is satisfied (even if the execution of the suppression control CNT _1A is canceled) It is determined that the system-side hunting phenomenon does not occur or hardly occurs), and the execution of the suppression control CNT _1A is canceled. By canceling the execution of the suppression control CNT _1A , the charge power amount of the power storage device 3 returns to the power storage reference power amount P _BREF (= 10).

That is, the control unit 23 performs the difference (P _B ) between the supplied power (generated power amount P _G , charged power amount P _B ′) and a predetermined value (power storage reference power amount P _BREF ) during execution of the hunting suppression control CNT _1A. When “−P _BREF ) satisfies the release condition, the hunting suppression control CNT _1A is configured to end. Release condition, the absolute value of the difference | P _B '-P _BREF | that is the threshold value TH _2A above, the absolute value of the difference | P _B' -P _BREF | is the first state is in a predetermined a threshold TH _2A above time (e.g., predetermined time T _L) continued that the difference (P _B '-P _BREF) is positive or negative and the second time condition is given is (e.g., a predetermined time T _L) continuing it, either It is.

For example, during the execution of the hunting suppression control CNT _1A , the determination unit 232 determines the difference (P _B ) between the supplied power (generated power amount P _G , charged power amount P _B ′) and a predetermined value (storage power reference power amount P _BREF ). It is determined whether or not “−P _BREF ) satisfies the release condition, and the result of the determination is given to the instruction unit 233. The instruction unit 233 is configured to end the hunting suppression control CNT _1A if the end determination result indicates that the release condition is satisfied.

Alternatively, for example, when the charge command amount P _B ^* is decreased from the storage reference power amount P _BREF by a predetermined amount ΔP _B ^* by the suppression control CNT _1A , the control unit 23 determines the difference (P _B ′ −P _B ^* ) _May be set as a determination target, and when the charge command amount P _B ^* is increased from the storage reference power amount P _BREF by the predetermined amount ΔP _B ^* by the suppression control CNT _1A , the control unit 23 determines the difference. (P _B ^* −P _B ′) may be set as a determination target.

In the determination target, P _B ^* may be replaced with the actually measured charging power amount P _B (that is, I _B × V _B ).

Then, when the determination target is equal to or greater than a predetermined positive threshold TH _2A ′, or when a state where the determination target is equal to or greater than the threshold TH _2A ′ is continuously observed for a predetermined time or longer, the control unit 23 The execution of the suppression control CNT _1A may be canceled by determining that the cancellation condition in the determination process J _1A is satisfied (TH _2A '> ΔP _B ^* ).

The control unit 23, when the difference between the supply during the hunting prevention control CNT _1A power (generated power) and the power demand (the amount of charging power) satisfies the release condition, terminates the hunting suppression control CNT _1A It may be configured to.

In this case, the release condition is that the absolute value of the difference between the generated electric energy and the charged electric energy is less than or equal to a predetermined threshold, or the absolute value of the difference between the generated electric energy and the charged electric energy is less than or equal to the predetermined threshold. A certain state has continued for a predetermined time. The predetermined threshold value is smaller than the range of change in the difference between the generated power amount and the charged power amount by execution of the hunting suppression control CNT _1A . Alternatively, the release condition may be that a state where the difference between the generated power amount and the charged power amount is positive or negative continues for a predetermined time.

Alternatively, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed a predetermined number of times during the execution of the hunting suppression control CNT _1A. The suppression control CNT _1A may be configured to end. The predetermined number may be one or more.

(2) Discharge quantitative control (2-1) Basic operation Next, discharge quantitative control will be described. The control unit 23 can supply power to the DC load 8 using the generated power of the power generation device 4 and the discharge power of the power storage device 3, but in the discharge quantitative control, at this time, the power storage device 3 has a constant discharge reference. The power conversion circuit 20 is controlled so as to be discharged under conditions.

In the discharge quantitative control, the control unit 23 uses the power storage device 3, the power generation device 4, and the power system 5 together to supply power to the DC load 8. In the discharge quantitative control, the power storage device 3 and the power generation device 4 are used as a power supply device, the DC load 8 is used as a power demand device, and the power system 5 is used as a power auxiliary device. Therefore, the power supply device includes a power generation device 4 and a power storage device 3 used as a power supply device. The supplied power is the total of the generated power that is the power supplied from the power generation device 4 and the power supply power (discharge power) that is the power obtained from the power supply device (power storage device 3). The demand power is power consumed by the DC load 8 (power consumption). Hereinafter, the magnitude of power consumption is referred to as power consumption. The power consumption is equal to, for example, the total amount of power consumed for 1 second.

In the discharge quantitative control, the control unit 23 (comparison unit 231) calculates the total value of the discharge power (discharge power amount) of the power storage device 3 and the generated power (generation power amount) of the power generation device 4 to the power consumption of the DC load 8 ( Compared with power consumption).

The control unit 23 (instruction unit 233) indicates that if the supply power (the sum of the discharge power and the generated power) is greater than the demand power (power consumption), the surplus of the supply power (the sum of the discharge power and the generated power) is the power system The power conversion circuit 20 is caused to execute output processing (power conversion for system output of the power conversion unit 21S) so as to be supplied to 5 (power auxiliary device).

Specifically, the control unit 23 (instruction unit 233) instructs the power conversion unit 21S (output power) so that output power corresponding to the difference between the total value of the discharged power and the generated power and the power consumption is obtained. Target value). For example, if the generated power is 13 kW · s and the discharged power is 10 kW · s, the supplied power is 23 kW · s. At this time, if the power consumption is 20 kW · s, the control unit 23 gives 3 kW · s to the power conversion unit 21S as the target value of the output power.

If the supplied power (the sum of the discharged power and the generated power) is less than the demand power (power consumption), the controller 23 (the instruction unit 233) has a shortage of the supplied power (the sum of the discharged power and the generated power) in the power system. The power conversion circuit 20 performs input processing (power conversion for system input of the power conversion unit 21S) so as to be supplemented by power from 5 (power auxiliary device).

Specifically, the control unit 23 (instruction unit 233) instructs the power conversion unit 21S (input power) so as to obtain input power corresponding to the difference between the total value of the discharge power and the generated power and the power consumption. Target value). For example, if the generated power is 6 kW · s and the discharged power is 10 kW · s, the supplied power is 16 kW · s. At this time, if the power consumption is 20 kW · s, the control unit 23 gives 4 kW · s to the power conversion unit 21S as the target value of the input power.

Thus, in this discharge quantitative control, when the total power amount of the power generation amount of the power generation device 4 and the discharge power amount of the power storage device 3 is smaller than the power consumption amount of the DC load 8, the shortage power corresponding to the difference between them. When (the amount of insufficient power) is input from the power system 5 to the power conversion circuit 20 and the total power amount is larger than the power consumption amount of the DC load 8, surplus power corresponding to the difference between them (surplus power) The control unit 23 controls the power conversion circuit 20 based on the input / output power information so that the power amount is output from the power conversion circuit 20 to the power system 5.

The discharge reference condition is a condition for designating a discharge power amount of the power storage device 3 or a current value and a voltage value depending on the discharge power amount, and the control unit 23 can freely determine the discharge reference condition. The discharge reference condition may be a condition for designating only one of a current value and a voltage value depending on the amount of discharge power of the power storage device 3. Here, it is assumed that the discharge reference condition specifies that the power storage device 3 is discharged with a constant reference power amount P _BREF for power storage.

When considering discharge quantitative control, the above-mentioned symbol P _B ^* is referred to as a symbol of the discharge command amount. The control unit 23 can generate a discharge command amount P _B ^* that specifies the amount of discharge power supplied from the power storage device 3 to the power conversion unit 21B and give the generated discharge command amount P _B ^* to the power conversion unit 21B.

Power conversion unit 21B, as the discharge amount of power specified by the discharge command amount P _B ^* is output from the power storage device 3, the discharging power conversion, including the control of the voltage value V _B and the current value I _B Do.

The discharge command amount P _B ^* may be formed from a voltage command amount and a current command amount that specify the voltage value V _B and the current value I _B.

In the discharge quantitative control, the control unit 23 can discharge the power storage device 3 with a constant reference power amount P _BREF for storage by substituting the value of the reference power amount P _BREF for storage into the discharge command amount P _B ^*. .

Again, for the sake of concrete explanation, consider that P _BREF = 10. Further, although the power consumption of the DC load 8 can fluctuate, it is assumed here that the power consumption of the DC load 8 is always 20 kW · s. When P _BREF = 10 in the discharge quantitative control, the control unit 23 can substitute 10 for the discharge command amount P _B ^* , and the discharge power amount becomes 10 kW · s.

In this case, for example, as shown in FIG. 10, if the power generation amount of the power generation device 4 is 6 kW · s, the total power amount is smaller than the power consumption amount 20 kW · s of the DC load 8. The control unit 23 controls the power conversion unit 21 S so that the insufficient power amount 4 kW · s corresponding to is input from the power system 5 to the power conversion circuit 20.

On the other hand, for example, as shown in FIG. 10, if the power generation amount of the power generation device 4 is 13 kW · s, the total power amount is larger than the power consumption amount 20 kW · s of the DC load 8, which corresponds to the difference between them. The control unit 23 controls the power conversion unit 21 S so that the surplus power amount 3 kW · s to be output is output from the power conversion circuit 20 to the power system 5.

As described above, in the discharge quantitative control, the generated power and power storage of the power generator 4 are absorbed while the shortage or surplus of the generated power of the power generator 4 is absorbed by the power input / output between the power conversion circuit 20 and the power system 5. In order to supply power to the DC load 8 using the discharge power of the device 3, the power storage device 3 is discharged under a certain discharge reference condition.

However, in the discharge quantitative control, as shown in FIG. 10C, when the total electric power has a value in the vicinity of the electric power consumption of the DC load 8, the change between the insufficient state and the surplus state of the generated power is performed. As a result, the switching of power input / output between the power conversion circuit 20 and the power system 5 repeatedly occurs in a relatively short period of time. Such switching at the time of execution of discharge quantitative control is also a system-side hunting phenomenon.

(2-2) System side hunting detection processing HD _1B
During the discharge quantitative control execution period, the control unit 23 can execute the system-side hunting detection process HD _1B . The system-side hunting detection process HD _1B is the same as the system-side hunting detection process HD _1A described above.

(2-3) System side hunting prediction processing HP _1B
Further, during the discharge quantitative control execution period, the control unit 23 may predict the occurrence of the system side hunting phenomenon by performing the system side hunting prediction process HP _1B based on the input / output power information.

For example, in the system-side hunting prediction process HP _1B , the control unit 23 generates power based on the current value I _G and the voltage value V _G (that is, based on the generated power amount P _G ) or based on the current value I _GINT and the voltage value V _INT. 'seeking, electric energy P _G' power amount P _G corresponding to the amount of power P _G total power amount of the power storage for the reference power P _BREF that is defined by the discharge reference condition (P _G '+ P _BREF) _Is compared with the power consumption P _C8 of the DC load 8.

The amount of power P _G ′ is the amount of power output from the power converter 21 _G and can be considered to be equal to the product (I _GINT × V _INT ). Here, it is considered that the discharge power of the storage reference power amount P _BREF (= 10) is supplied to the DC load 8 from the power conversion unit 21B by the discharge quantitative control. Therefore, the total power amount (P _G ′ + P _BREF ) is the total power amount output from the

power conversion units

21G and 21B based on the generated power of the power generation device 4 and the discharge power of the power storage device 3 (power conversion circuit 20 If the power loss is ignored, P _G ′ + P _BREF = P _G + P _B ).

Then, the control unit 23 determines _{whether or not} the absolute value of the difference between the total power amount (P _G '+ P _BREF ) and the power consumption amount of the DC load 8 is equal to or less than a predetermined positive threshold value TH _3A. When the state where the value is equal to or less than the threshold TH _3A is continuously observed for a predetermined time or more, the system side hunting prediction determination is made.

That is, the control unit 23 (determination unit 232) determines the absolute value of the difference between the supplied power (the total value of the power storage reference power P _BREF and the power P _G ′) and the demand power (power consumption P _C8 ) | It is determined whether or not P _BREF + P _G ′ −P _C8 | is equal to or less than a determination value (threshold TH _3A ), and it is determined that the absolute value | P _BREF + P _G ′ −P _C8 | is equal to or less than the determination value TH _3A . The event is configured to determine that an event has occurred.

Note that the control unit 23 (determination unit 232) determines the absolute value of the difference between the supplied power (the total value of the power storage reference power P _BREF and the power P _G ′) and the demand power (power consumption P _C8 ) | When it is determined whether or not the state where P _BREF + P _G '−P _C8 | is equal to or less than the determination value (threshold value TH _3A ) has continued for the determination time (the predetermined time described above), It may be configured to determine that an event has occurred.

(2-4) Hunting suppression control CNT _1B
When the system-side hunting detection determination or the system-side hunting prediction determination is made during the execution of the discharge quantitative control, the control unit 23 sets the discharge power amount of the power storage device 3 according to the discharge reference condition P Hunting suppression control CNT _1B changed from _BREF is executed.

In the hunting suppression control CNT _1B , the absolute value of the input / output power amount between the power conversion circuit 20 and the power system 5 is increased by changing the discharge power amount, thereby suppressing the system-side hunting phenomenon. The suppression control CNT _1B is control performed in the discharge quantitative control, and the contents of the discharge quantitative control are corrected during the execution period of the suppression control CNT _1B .

That is, the control unit 23 (instruction unit 233) is configured to execute the hunting suppression control CNT _1B when it is determined that an event has occurred during the discharge quantitative control execution period. In the hunting suppression control CNT _1B , the control unit 23 (instruction unit 233) is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

A first implementation example of the suppression control CNT _1B will be described. Before the system-side hunting recognition timing, as described above, the control unit 23 substitutes the power storage reference power amount P _BREF for the discharge command amount P _B ^* , whereby the discharge power amount of the power storage device 3 becomes the power storage reference power amount. It corresponds to the electric energy P _BREF (= 10) (see FIGS. 10A, 10B, and 10C).

However, when the system-side hunting detection determination or the system-side hunting prediction determination is made, in the first implementation example of the suppression control CNT _1B , the control unit 23 stores the discharge command amount P _B ^* by a predetermined amount ΔP _B ^* for power storage. Increase or decrease from the reference power amount P _BREF (that is, change the discharge command amount P _B ^* with reference to before the system-side hunting recognition timing).

That is, the control unit 23 (instruction unit 233) is configured to execute normal control for setting the target value to a predetermined value (storage power reference amount P _BREF ) until it is determined that an event has occurred. In the hunting suppression control CNT _1B , the control unit 23 is configured to set the target value to a value (P _BREF ± ΔP _B ^* ) different from the predetermined value (storage power reference P _BREF ).

Thus, in the first implementation example, the control unit 23 (instruction unit 233) increases or decreases the discharge power so that the difference between the total value of the discharge power and the generated power and the power consumption increases.

FIG. 11A shows a power input / output state when the discharge command amount P _B ^* is increased by 2 from the power storage reference power amount P _BREF (= 10). Here, the control unit 23 sets the target value to 12 (= P _BREF + ΔP _B ^* ), which is a value different from the storage reference power amount P _BREF (= 10) (ΔP _B ^* = 2).

In this state, since the surplus power amount 2 kW · s is included in the generated power amount of the power generation device 4 and the discharge power amount of the power storage device 3, the control unit 23 determines that the surplus power amount 2 kW · s is the power conversion circuit 20. The power conversion unit 21S is controlled so as to be output to the power system 5. That is, the absolute value of the input / output power amount between the power conversion circuit 20 and the power system 5 with the increase in the discharge power amount by the suppression control CNT _1B as a reference (based on the state of FIG. 10C). Will increase. As a result, the system side hunting phenomenon is appropriately suppressed. The same _applies to the case where the discharge command amount P _B ^* is decreased from the reference power amount P _BREF for power storage.

For example, the control unit 23 may set the target value to 8 (= P _BREF −ΔP _B ^* ), which is a value different from the reference power amount P _BREF (= 10) for storage (ΔP _B ^* = 2).

In this state, the control unit 23 converts the power so that an insufficient power amount 2 kW · s corresponding to the difference between the total value of the discharge power and the generated power and the power consumption is input from the power system 5 to the power conversion circuit 20. The unit 21S is controlled. As a result, the system side hunting phenomenon is appropriately suppressed.

Thus, in the first implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is the target value of the power source power (discharge power). That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21B.

A second implementation example of the suppression control CNT _1B will be described. When the system-side hunting detection determination or the system-side hunting prediction determination is made, the control unit 23 that performs the second implementation example of the suppression control CNT _1B uses the system input / output command amount P _S as a reference before the system-side hunting recognition timing. ^The suppression control CNT _1B is realized by changing ^* by a predetermined amount ΔP _S ^* and assigning the change to the change in the amount of discharge power of the power storage device 3.

That is, in the normal control, the control unit 23 (instruction unit 233) obtains input power or output power corresponding to the difference between the supplied power (the total value of the discharge power and the generated power) and the demand power (power consumption). Thus, an instruction (target value of input power or output power) is given to the power conversion unit 21S. On the other hand, in the hunting suppression control CNT _1B , the control unit 23 (instruction unit 233) sets a target value (target value of input power or output power) to be given to the power conversion unit 21S to a predetermined value. That is, the control unit 23 performs either the input process or the output process on the power conversion unit 21S regardless of the difference between the supplied power (the total value of the discharge power and the generated power) and the demand power (power consumption). Let it be done.

For example, the state of FIG. 10C, that is, the state where the total amount of power generated by the power generation device 4 and the amount of discharge power of the power storage device 3 matches the power consumption of the DC load 8 is shown in FIG. As shown, this corresponds to a state where zero is substituted for the command amount P _S ^* .

In this state, when the system-side hunting detection determination or the system-side hunting prediction determination is made, the control unit 23 changes the system input / output command amount (target value of output power) P _S ^* from zero to a predetermined value (for example, It is possible to execute the suppression control CNT _1B that is changed to 2) (here, it is considered that the state where P _S ^* > 0 corresponds to the power output state from the power conversion unit 21S to the power system 5).

In the second implementation example of the suppression control CNT _1B , the control unit 23 prioritizes the system input / output command amount P _S ^* over the discharge command amount P _B ^* , or gives the discharge command amount P _B ^* to the power conversion unit 21B. Don't give. In any case, in the suppression control CNT _1B , the control unit 23 is determined by the amount of power generated by the power generation device 4, the amount of input / output power between the power conversion circuit 20 and the power system 5, and the power consumption of the DC load 8. Then, the power conversion unit 21B is controlled so that the insufficient power (the shortage of power to be supplied to the DC load 8) is discharged from the power storage device 3.

In this case, the amount of generated power is 10 kW · s, but output power of 2 kW · s is supplied to the power system 5. Therefore, when the power consumption is 20 kW · s, the shortage of the power consumption is 12 kW · s. Therefore, the control unit 23 (instruction unit 233) increases the discharge command amount P _B ^* from the storage reference power amount P _BREF (= 10 kW · s) to 12 kW · s. That is, the control unit 23 gives 12 kW · s as a target value to the power conversion unit 21B. As a result, as shown in FIG. 12, the power storage device 3 outputs discharge power for 12 W · s that is _larger than the power storage reference power amount P _BREF . This state is equivalent to the state shown in FIG.

FIG. 12 shows an example in which the command amount P _S ^* is changed so that power output from the power conversion circuit 20 to the power system 5 is performed, but power input from the power system 5 to the power conversion circuit 20 is performed. The command amount P _S ^* may be changed to be performed. In this case, the discharge power amount of the power storage device 3 is reduced from 10 kW · s.

For example, the control unit 23 can execute the suppression control CNT _1B that changes the system input / output command amount (target value of input power) P _S ^* from zero to a predetermined value (for example, −2) (here, The state where P _S ^* <0 corresponds to the power input state from the power system 5 to the power conversion unit 21S).

In this case, the amount of generated power is 10 kW · s, but input power of 2 kW · s is supplied from the power system 5. Therefore, when the power consumption is 20 kW · s, the shortage of the power consumption is 8 kW · s. Therefore, the control unit 23 (instruction unit 233) decreases the discharge command amount P _B ^* from the storage reference power amount P _BREF (= 10 kW · s) to 8 kW · s. That is, the control unit 23 gives 8 kW · s as a target value to the power conversion unit 21B. As a result, discharge power of 8 kW · s, which is smaller than the reference power amount P _BREF for power storage, is output from the power storage device 3.

Thus, in the second implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is a target value of input power or output power. That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21S.

In the first implementation example of the suppression control CNT _1B , the discharge power amount is directly controlled by controlling the discharge command amount P _B ^* , whereas in the second implementation example of the suppression control CNT _1B , the system input / output command amount P _The discharge power amount is indirectly controlled by controlling _S ^* (by controlling the input / output power amount between the power conversion circuit 20 and the power system 5).

(2-5) cancellation determination processing J _1B corresponding to suppression control CNT _1B
Control unit 23, during the execution period of the suppression control CNT _1B, through the success determination of a predetermined cancellation condition, performing the cancellation determination processing J _1B determines whether to cancel the execution of the suppression control CNT _1B Can do.

For example, in the _{cancelability} determination process J _1B , the control unit 23 _{obtains the} total power amount (P _G '+ P _BREF ) by the above-described method, and _calculates the total power amount (P _G ' + P _BREF ) and the power consumption amount of the DC load 8. _{Is obtained} (if the power loss of the power conversion circuit 20 is ignored, P _G ′ + P _BREF = P _G + P _B ).

In the determination process J _1B , the control unit 23 continues the state where the absolute value is equal to or greater than the predetermined positive threshold TH _4A or the absolute value is equal to or greater than the threshold TH _4A for a predetermined time or longer. When observed, or when a state in which the absolute value is positive is continuously observed for a predetermined time or more, it is determined that the release condition in the determination process J _1B is satisfied (execution of the suppression control CNT _1B is performed). It is determined that the system-side hunting phenomenon does not occur or is unlikely to occur even if it is canceled), and the execution of the suppression control CNT _1B is canceled. By canceling the execution of the suppression control CNT _1B , the discharge power amount of the power storage device 3 returns to the power storage reference power amount P _BREF (= 10).

That is, during the execution of the hunting suppression control CNT _1B , the control unit 23 _calculates the total value (P _G '+ P _BREF ) of the generated power P _G ' and the predetermined value (reference power storage amount) P _BREF and the demand power (power consumption). When the difference (P _G '+ P _BREF -P _C8 ) from the amount P _C8 ) satisfies the release condition, the hunting suppression control CNT _1B is configured to end. Release condition, the absolute value of the difference | is the threshold TH _4A above state _{_{| P G '+ P BREF -P}} C8 | that is the threshold value TH _4A above, the absolute value of the difference _{_{| P G' + P BREF -P}} C8 Continued for a predetermined first time (for example, the above-mentioned predetermined time), and a state in which the difference (P _G ′ + P _BREF −P _C8 ) is positive or negative continues for a predetermined second time (for example, the above-mentioned predetermined time) Either

For example, during the execution of the hunting suppression control CNT _1B , the determination unit 232 includes the total value (P _G '+ P _BREF ) of the generated power P _G ′ and the predetermined value (reference power storage amount) P _BREF and the demand power (power consumption). It is determined whether or not the difference (P _G '+ P _BREF −P _C8 ) from the amount P _C8 ) satisfies the release condition, and the result of the end determination is given to the instruction unit 233. The instruction unit 233 is configured to end the hunting suppression control CNT _1B if the end determination result indicates that the release condition is satisfied.

Alternatively, for example, when the suppression control CNT _1B has reduced the discharge command amount P _B ^* from the predetermined amount [Delta] P _B ^* only energy storage for the reference power P _BREF, the control unit 23 the difference (P _C8 - (P _G ' + P _B ^* )) may be set as a determination target, and control is performed when the discharge command amount P _B ^* is increased from the storage reference power amount P _BREF by a predetermined amount ΔP _B ^* by the suppression control CNT _1B. The unit 23 may set the difference ((P _G '+ P _B ^* ) − P _C8 ) as a determination target.

In the determination target, P _B ^* may be replaced with the actually measured discharge power amount P _B (that is, I _B × V _B ). P _C8 represents the power consumption of the DC load 8.

Then, when the determination target is equal to or greater than a predetermined positive threshold TH _4A ′, or when a state where the determination target is equal to or greater than the threshold TH _4A ′ is continuously observed for a predetermined time or longer, the control unit 23 The execution of the suppression control CNT _1B may be canceled by determining that the cancellation condition in the determination process J _1B is satisfied (TH _4A '> ΔP _B ^* ).

The control unit 23 determines that the difference between the supplied power (the total amount of generated power and the discharged power) and the demand power (power consumption) satisfies the release condition during the execution of the hunting suppression control CNT _1B. The hunting suppression control CNT _1B may be configured to end.

In this case, the release condition is that the absolute value of the difference between the total value of the generated power amount and the discharged power amount and the consumed power amount is equal to or less than a predetermined threshold, or the total value of the generated power amount and the discharged power amount That is, a state where the absolute value of the difference between the power consumption and the power consumption amount is equal to or less than a predetermined threshold value continues for a predetermined time. The predetermined threshold value is smaller than the range of change in the difference between the total value of the generated power amount and the discharged power amount and the consumed power amount due to the execution of the hunting suppression control CNT _1B . Alternatively, the release condition may be that a state where the difference between the total value of the generated power amount and the discharged power amount and the consumed power amount is positive or negative continues for a predetermined time.

Alternatively, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed a predetermined number of times during the execution of the hunting suppression control CNT _1B , and determines that the switching operation has been performed the predetermined number of times. The suppression control CNT _1B may be configured to end. The predetermined number may be one or more.

(3) System output quantitative control (3-1) Basic operation Next, system output quantitative control will be described. In the system output quantitative control, the control unit 23 controls the power conversion circuit 20 so that power is output from the power conversion circuit 20 to the power system 5 under a certain system output reference condition using the generated power of the power generation device 4. To do.

In the system output quantitative control, the control unit 23 supplies power to the power system 5 using the power storage device 3 and the power generation device 4. In the system output quantitative control, the power generation device 4 is used as a power supply device, the power system 5 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device. Therefore, in the grid output quantitative control, the supplied power is the generated power of the power generator 4. The demand power is power (output power) supplied to the power system 5.

In the grid output quantitative control, the control unit 23 (comparison unit 231) compares the generated power (generated power amount) of the power generation device 4 with the output power (output power amount) of the power system 5.

If the supplied power (generated power) is greater than the demand power (output power), the control unit 23 (instruction unit 233) may supply an excess of the supplied power (generated power) to the power storage device 3 (power auxiliary device). The power conversion circuit 20 is caused to execute output processing (power conversion for charging of the power conversion unit 21B).

Specifically, the control unit 23 (instruction unit 233) gives an instruction (target value of charging power) to the power conversion unit 21B so that charging power corresponding to the difference between the generated power and the output power can be obtained. For example, if the supplied power amount is 13 kW · s and the output power amount is 10 kW · s, 3 kW · s is given to the power conversion unit 21B as the target value of the charging power.

If the supply power (generated power) is less than the demand power (output power), the control unit 23 (instruction unit 233) compensates for the shortage of the supplied power (generated power) with the power from the power storage device 3 (power auxiliary device). In this manner, the power conversion circuit 20 is caused to execute input processing (discharge power conversion of the power conversion unit 21B).

Specifically, the control unit 23 (instruction unit 233) gives an instruction (target value of the discharge power) to the power conversion unit 21B so that the discharge power corresponding to the difference between the generated power and the output power can be obtained. For example, if the supply power amount is 6 kW · s and the output power amount is 10 kW · s, the control unit 23 gives 4 kW · s to the power conversion unit 21B as the target value of the discharge power.

As described above, in the grid output quantitative control, when the power generation amount of the power generation device 4 is smaller than the power amount (output power amount) required for the output to the power system 5, the shortage power (insufficient) corresponding to the difference between them. If the amount of power generated by the power generation device 4 is larger than the amount of power (output power amount) required for output to the power system 5, this corresponds to the difference between them. Based on the input / output power information, the control unit 23 controls the power conversion circuit 20 so that the power storage device 3 is charged with surplus power (surplus power amount). When system output quantitative control is considered, the presence of the DC load 8 is ignored (regardless of the presence or absence of the DC load 8).

The system output reference condition is a condition for designating an output power amount from the power conversion circuit 20 to the power system 5 or a current value and a voltage value depending on the output power amount, and the control unit 23 freely sets the system output reference condition. Can be determined. The system output reference condition may be a condition for designating only one of the current value and the voltage value depending on the output power amount from the power conversion circuit 20 to the power system 5. Here, it is assumed that the grid output reference condition specifies that the power conversion circuit 20 outputs power to the power grid 5 at a constant grid reference power amount (system input / output reference power amount) P _SREF .

In the system output quantitative control, the power flow between the power conversion circuit 20 and the power system 5 is limited from the power conversion circuit 20 to the power system 5, so the system input / output command amount P _S ^{* is changed} to the system output command amount P _S ^*. Also say. In the system output quantitative control, the control unit 23 gives the system output command amount P _S ^* into which the value of the system reference power amount P _SREF is substituted to the power conversion unit 21S, so that the system is transferred from the power conversion unit 21S to the power system 5. The power of the reference power amount P _SREF can be output.

Now, consider P _SREF = 10 for the sake of concrete explanation. In the system output quantitative control, when P _SREF = 10, the control unit 23 can substitute 10 for the system output command amount P _S ^* .

In this case, for example, as shown in FIG. 13A, if the amount of power generated by the power generation device 4 is 6 kW · s, the amount of power generated by the power generation device 4 is 10 kW necessary for output to the power system 5. Since it is less than s (= P _S ^* ), the control unit 23 controls the power conversion unit 21B so that the power shortage 4 kW · s corresponding to the difference between them is discharged from the power storage device 3.

On the other hand, for example, as shown in FIG. 13 (b), if the amount of power generated by the power generator 4 is 13 kW · s, the amount of power generated by the power generator 4 is 10 kW · s required for output to the power system 5. since (= P _S ^*) greater than, as power storage device 3 is charged by excess power amount 3 kW · s corresponding to their difference, the control unit 23 controls the power conversion unit 21B.

Thus, in the system output quantitative control, the power conversion circuit 20 uses the generated power of the power generation device 4 while absorbing the shortage or surplus of the generated power of the power generation device 4 by charging or discharging the power storage device 3. Electric power is output to the electric power system 5 under a certain system output reference condition.

(3-2) Storage-side hunting phenomenon However, in the grid output quantitative control, if the generated power amount of the power generator 4 has a value near the grid reference power amount P _SREF as shown in FIG. Switching between input and output of power between the power conversion circuit 20 and the power storage device 3 (switching between charging and discharging) occurs repeatedly in a relatively short period due to the transition between the shortage state and the surplus state of the generated power. Such switching at the time of executing the system output quantitative control is called a power storage side hunting phenomenon.

In other words, the hunting phenomenon in the grid output quantitative control is a storage-side hunting phenomenon in which the power conversion circuit 20 alternately repeats output processing (charging power conversion) and input processing (discharging power conversion) in a relatively short time. is there.

Switching due to the power storage side hunting phenomenon is not preferable for the power storage device 3 and can promote deterioration of the power storage device 3.

(3-3) Storage-side hunting detection processing HD _1C
During the execution period of the system output quantitative control, the control unit 23 can detect the occurrence of the power storage side hunting phenomenon by performing the power storage side hunting detection process HD _1C based on the input / output power information.

In the power storage side hunting detection process HD _1C , the control unit 23 switches the input / output of power between the power conversion unit 21B and the power storage device 3 for a predetermined time based on the current value I _B or I _BINT included in the input / output power information. When it is detected a predetermined number of times or more, a storage side hunting detection determination is made.

That is, when the power conversion circuit 20 performs a switching operation between the output process (power conversion for charging) and the input process (power conversion for discharge) a predetermined number of times or more within a predetermined time, the control unit 23 (determination unit 232). The event (that is, the occurrence of the hunting phenomenon in the power conversion circuit 20) is determined to occur.

The predetermined number of times may be any number of 1 or more, but 2 or more is desirable. The storage-side hunting detection determination means that it is determined that the storage-side hunting phenomenon is currently occurring.

(3-4) Storage-side hunting prediction processing HP _1C
Further, during the execution period of the system output quantitative control, the control unit 23 may predict the occurrence of the power storage side hunting phenomenon by performing the power storage side hunting prediction process HP _1C based on the input / output power information (that is, It may be predicted whether the storage-side hunting phenomenon is likely to occur in the future).

For example, in the power storage side hunting prediction process HP _1C , the control unit 23 generates power based on the current value I _G and the voltage value V _G (that is, based on the generated power amount P _G ) or based on the current value I _GINT and the voltage value V _INT. The system output power amount P _S ′ corresponding to the power amount P _G is obtained, and the system output power amount P _S ′ is compared with the system reference power amount P _SREF defined by the system output reference condition. Then, the control unit 23 determines that the absolute value | P _S '−P _SREF | of the difference is equal to or less than the predetermined positive threshold value TH _5A or the absolute value | P _S ' −P _SREF | _A storage-side hunting prediction determination is made when a state of _{5 A} or less is continuously observed for a predetermined time or more.

The storage side hunting prediction determination means that it is determined that the storage side hunting phenomenon is likely to occur in the near future. The grid output power amount P _S ′ corresponding to the generated power amount P _G indicates the output power amount for the power system 5 based on the generated power amount P _G of the power generation device 4, and the power conversion efficiency of the

power conversion units

21G and 21S. The system output power P _S ′ can be obtained using the product “I _G × V _G ” or using the power conversion efficiency of the power conversion unit 21 _< / _b> S and the product “I _GINT × V _INT ”. Assuming zero power loss of the

power converter

21G and 21S, a P _S '= P _G.

That is, the control unit 23 (determination unit 232) determines that the absolute value | P _S '−P _SREF | of the difference between the supplied power (system output power amount P _S ′) and the demand power (system reference power amount P _SREF ) is decision value determines whether a (threshold TH _5A) below, the absolute value | is configured to determine that an event has occurred when it is determined that less than the determination value TH _5A | P _S '-P _SREF The

The control unit 23 (determination unit 232) determines that the absolute value | P _S '−P _SREF | of the difference between the supplied power (system output power amount P _S ′) and the demand power (system reference power amount P _SREF ) is It is configured to determine whether or not a state equal to or less than a determination value (threshold value TH _5A ) has continued for a determination time (the predetermined time described above), and to determine that an event has occurred when it is determined that the state has continued for the determination time May be.

(3-5) Hunting suppression control CNT _1C
When the storage-side hunting detection determination or the storage-side hunting prediction determination is made during the execution period of the system output quantitative control, the control unit 23 sets the output power amount from the power conversion circuit 20 to the power system 5 as the system output reference condition. The hunting suppression control CNT _1C that is changed from the system reference power amount P _SREF is executed.

In the hunting suppression control CNT _1C , by changing the output power amount from the power conversion circuit 20 to the power system 5, the absolute value of the input / output power amount between the power conversion circuit 20 and the power storage device 3 is increased, thereby storing power. Suppresses side hunting phenomenon. The input / output power amount between the power conversion circuit 20 and the power storage device 3 is an input power amount from the power storage device 3 to the power conversion circuit 20 (that is, a discharge power amount of the power storage device 3) or from the power conversion circuit 20 to the power storage device 3. Output electric energy (that is, charging electric energy of the power storage device 3). The timing at which the storage-side hunting detection determination or the storage-side hunting prediction determination is made is also referred to as a storage-side hunting recognition timing. The control unit 23 can start the suppression control CNT _1C from the storage side hunting recognition timing (the same applies to the hunting suppression control CNT _1D described later). The suppression control CNT _1C is control performed in the system output quantitative control, and correction is made to the content of the system output quantitative control during the execution period of the suppression control CNT _1C .

That is, the control unit 23 (instruction unit 233) is configured to execute the hunting suppression control CNT _1C when it is determined that an event has occurred during the execution period of the system output quantitative control. In the hunting suppression control CNT _1C , the control unit 23 (instruction unit 233) is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

In the following description, the output power or output power amount from the power conversion circuit 20 to the power system 5 may be simply referred to as output power or output power amount to the power system 5. The input power or input power amount to 20 may be simply referred to as input power or input power amount from the power system 5.

A first implementation example of the suppression control CNT _1C will be described. Before the storage side hunting recognition timing, as described above, the control unit 23 substitutes the system reference power amount P _SREF for the system output command amount P _S ^* , and the output power amount to the power system 5 is thereby reduced. This is consistent with the reference power amount P _SREF (= 10) (see FIGS. 13A, 13B, and 13C).

However, when the storage-side hunting detection determination or the storage-side hunting prediction determination is made, in the first implementation example of the suppression control CNT _1C , the control unit 23 reduces the system output command amount P _S ^* to the system by a predetermined amount ΔP _S ^*. The reference power amount P _{SREF is} increased or decreased (that is, the system output command amount P _S ^* is changed with reference to the timing before the power storage side hunting recognition timing). Here, “ΔP _S ^* > 0”. The predetermined amount ΔP _S ^* may be an amount that depends on the grid reference power amount P _SREF (for example, the product of P _SREF and the coefficient k).

That is, the control unit 23 (instruction unit 233) is configured to execute normal control for setting the target value to a predetermined value (system reference power amount P _SREF ) until it is determined that an event has occurred. In the hunting suppression control CNT _1C , the control unit 23 is configured to set the target value to a value (P _SREF ± ΔP _S ^* ) different from the predetermined value (system reference power amount P _SREF ).

Thus, in the first implementation example, the control unit 23 (instruction unit 233) increases or decreases the output power so that the difference between the generated power and the output power becomes large.

FIG. 14A shows a power input / output state when the system output command amount PS * is increased by 2 from the system reference power amount PSREF (= 10). Here, the control unit 23 sets the target value to 12 (= P _SREF + ΔP _S ^* ), which is a value different from the reference power amount P _SREF (= 10) for the system (ΔP _S ^* = 2).

In this state, the control unit 23 causes the power conversion unit 21 B so that the insufficient power amount 2 kW · s corresponding to the difference between the generated power amount of the power generation device 4 and the system output command amount P _S ^* is discharged from the power storage device 3. To control. That is, the input / output between the power conversion circuit 20 and the power storage device 3 is based on the increase in the amount of output power to the power system 5 due to the suppression control CNT _1C (based on the state before FIG. 13C). The absolute value of the electric energy increases. As a result, the power storage side hunting phenomenon is appropriately suppressed. The same applies when the system output command amount P _S ^* is reduced from the system reference power amount P _SREF .

For example, the control unit 23 may set the target value to 8 (= P _SREF −ΔP _S ^* ), which is a value different from the system reference power amount P _SREF (= 10) (ΔP _S ^* = 2).

In this state, the control unit 23 controls the power conversion unit 21B so that the surplus power amount 2 kW · s corresponding to the difference between the supplied power and the output power is supplied from the power conversion circuit 20 to the power storage device 3. As a result, the power storage side hunting phenomenon is appropriately suppressed.

Thus, in the first implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is a target value of demand power (output power). That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21S.

A second implementation example of the suppression control CNT _1C will be described. When the storage-side hunting detection determination or the storage-side hunting prediction determination is made, the control unit 23 that performs the second implementation example of the suppression control CNT _1C uses the charging command to the power conversion unit 21B with reference to the timing before the storage-side hunting recognition timing. The suppression control CNT _1C is realized by changing the amount or the discharge command amount P _B ^* by a predetermined amount ΔP _B ^* and assigning the change amount to the change in the output power amount from the power conversion circuit 20 to the power system 5. Here, “ΔP _B ^* > 0”. The predetermined amount ΔP _B ^* may be an amount depending on the grid reference power amount P _SREF , for example, the product of P _SREF and the coefficient k.

That is, in the normal control, the control unit 23 (instruction unit 233) instructs the power conversion unit 21B (charging power or discharging power so that charging power or discharging power corresponding to the difference between the generated power and the output power is obtained. Target value). In contrast, in the hunting suppression control CNT _1C , the control unit 23 (instruction unit 233) sets a target value (target value of charging power or discharging power) to be given to the power conversion unit 21B to a predetermined value. In other words, the control unit 23 causes the power conversion unit 21B to perform either input processing or output processing regardless of the difference between the supplied power (generated power) and the demand power (output power).

For example, in the state of FIG. 13C, that is, the state where the amount of power generated by the power generation device 4 and the amount of power output to the power system 5 are both 10 kW · s, as shown in FIG. This corresponds to a state where zero is substituted for the discharge command amount (PB *).

In this state, when the storage-side hunting detection determination or the storage-side hunting prediction determination is made, for example, the control unit 23 changes the discharge command amount (target value of discharge power) P _B ^* from zero to a predetermined value (for example, 2). Suppression control CNT _1C to be changed to can be executed.

In the second implementation example of the suppression control CNT _1C , the control unit 23 prioritizes the discharge command amount (or charge command amount) P _B ^* over the system output command amount P _S ^* or the system output command amount P _S. ^* Is not given to the power converter 21S. In any case, in the suppression control CNT _1C , the control unit 23 controls the power conversion unit 21S so that the total power amount of the power generation amount of the power generation device 4 and the discharge power of the power storage device 3 is output to the power system 5. .

In this case, the amount of generated power is 10 kW · s, but 2 kW · s of discharge power is supplied from the power storage device 3 to the power conversion circuit 20. Therefore, the power that can be supplied to the power system 5 is 12 kW · s. Therefore, the control unit 23 (instruction unit 233) increases the system output command amount P _S ^* from the system reference power amount P _SREF (= 10 kW · s) to 12 kW · s. That is, the control unit 23 gives 12 kW · s as a target value to the power conversion unit 21S. As a result, the power grid 5 is supplied with 12 kW · s of output power that is greater than the grid reference power amount P _SREF . As a result, as shown in FIG. 15, 12 kW · s of power is output from the power conversion circuit 20 to the power system 5. This state is equivalent to the state shown in FIG.

Figure 15 is an example of when the discharge of the power storage device 3 has changed the command amount P _B ^* to take place, even by changing the command value P _B ^* as charging of the electricity storage device 3 is carried out In that case, the output power amount to the electric power system 5 is reduced from 10 kW · s.

For example, the control unit 23 can execute the suppression control CNT _1C that changes the charging command amount (target value of charging power) P _B ^* from zero to a predetermined value (for example, 2).

In this case, the amount of generated power is 10 kW · s, but the power storage device 3 is supplied with 2 kW · s of charging power. Therefore, the power that can be supplied to the power system 5 is 8 kW · s. Therefore, the control unit 23 (instruction unit 233) decreases the system output command amount P _S ^* from the system reference power amount P _SREF (= 10 kW · s) to 8 kW · s. That is, the control unit 23 gives 8 kW · s as a target value to the power conversion unit 21S. As a result, the output power is supplied to the power system 5 by 8 kW · s, which is smaller than the system reference power amount P _SREF .

Thus, in the second implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is a target value of charging power or discharging power. That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21B.

In the first implementation example of the suppression control CNT _1C , the output power amount to the power system 5 is directly controlled by controlling the system output command amount P _S ^* , whereas in the second implementation example of the suppression control CNT _1C , The output power amount to the power system 5 is indirectly controlled by controlling the charge or discharge command amount P _B ^* (by controlling the input / output power amount between the power conversion circuit 20 and the power storage device 3).

(3-6) cancellation determination processing J _1C corresponding to suppression control CNT _1C
Control unit 23, during the execution period of the suppression control CNT _1C, through the success determination of a predetermined cancellation condition, performing the determining cancellation determination processing J _1C whether to cancel the execution of the suppression control CNT _1C Can do.

For example, in the cancelability determination process J _1C , the control unit 23 performs the above-described operation based on the current value I _G and the voltage value V _G (that is, based on the generated power amount P _G ) or based on the current value I _GINT and the voltage value V _INT. System output power P _S ′ is obtained and the system output power P _S ′ is compared with the system reference power P _SREF defined by the system output reference condition (the power of the

power converters

21G and 21S) neglecting losses, a P _S '= P _G).

In the determination process J _1C , the control unit 23 determines that the absolute value | P _S '−P _SREF | of the difference is equal to or greater than a predetermined positive threshold TH _6A or the absolute value | P _S ' −. When a state where P _SREF | is equal to or greater than the threshold TH _6A is continuously observed for a predetermined time or longer, or a state where the absolute value | P _S '−P _SREF | is positive is continuously observed for a predetermined time or longer. The release condition in the determination process J _1C is determined to be satisfied (determined that the storage-side hunting phenomenon does not occur or hardly occurs even if the execution of the suppression control CNT _1C is canceled), and the suppression control CNT _1C Cancel execution. By canceling the execution of the suppression control CNT _1C , the output power amount to the power system 5 returns to the grid reference power amount P _SREF (= 10).

That is, the control unit 23 performs the difference (P) between the supplied power (generated power amount P _G , system output power amount P _S ′) and a predetermined value (system reference power amount P _SREF ) during execution of the hunting suppression control CNT _1C. _When _S′− P _SREF ) satisfies the release condition, the hunting suppression control CNT _1C is configured to end. Release condition, the absolute value of the difference | P _S '-P _SREF | is equal to or greater than the threshold TH _6A, the absolute value of the difference | P _S' -P _SREF | is the first state is in a predetermined is equal to or greater than the threshold TH _6A Either the time (for example, the above-mentioned predetermined time) has been continued, or the state where the difference (P _S '−P _SREF ) is positive or negative has continued for a predetermined second time (for example, the above-mentioned predetermined time) It is.

For example, during the execution of the hunting suppression control CNT _1C , the determination unit 232 determines the difference between the supplied power (generated power amount P _G , system output power amount P _S ′) and a predetermined value (system reference power amount P _SREF ) (P _S '-P _SREF) performs the cancellation condition is satisfied whether end determination, giving the result of the completion determination instructing section 233. The instruction unit 233 is configured to end the hunting suppression control CNT _1C if the result of the end determination indicates that the release condition is satisfied.

Alternatively, for example, when the system output command amount P _S ^* is decreased from the system reference power amount P _SREF by a predetermined amount ΔP _S ^* by the suppression control CNT _1C , the control unit 23 determines the difference (P _S ′ −P _S ^* ) May be set as a determination target, and when the system output command amount P _S ^* is increased from the system reference power amount P _SREF by the predetermined amount ΔP _S ^* by the suppression control CNT _1C , the control unit 23 The difference (P _S ^* −P _S ′) may be set as a determination target.

In the determination target, P _S ^* may be replaced with the actually measured output power P _S (ie, I _S × V _S ).

Then, when the determination target is greater than or equal to the predetermined positive threshold TH _6A ′, or when a state where the determination target is greater than or equal to the threshold TH _6A ′ is continuously observed for a predetermined time or longer, the control unit 23 determines The execution of the suppression control CNT _1C may be canceled by determining that the cancellation condition in the process J _1C is satisfied (TH _6A '> ΔP _S ^* ).

The control unit 23, when the difference between the supply during the hunting prevention control CNT _1C power (generated power) and the power demand (the amount of output power) satisfies the release condition, terminates the hunting suppression control CNT _1C It may be configured to.

In this case, the release condition is that the absolute value of the difference between the generated electric energy and the output electric energy is less than or equal to a predetermined threshold, or the absolute value of the difference between the generated electric energy and the output electric energy is less than or equal to the predetermined threshold. A certain state has continued for a predetermined time. The predetermined threshold value is smaller than the range of change in the difference between the generated power amount and the output power amount due to the execution of the hunting suppression control CNT _1C . Alternatively, the cancellation condition may be that the state where the difference between the generated power amount and the output power amount is positive or negative continues for a predetermined time.

Alternatively, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed a predetermined number of times during the execution of the hunting suppression control CNT _1C , and determines that the switching operation has been performed the predetermined number of times. The suppression control CNT _1C may be configured to end. The predetermined number may be one or more.

(4) System input quantitative control (4-1) Basic operation Next, system input quantitative control will be described. The control unit 23 can supply power to the DC load 8 using the generated power of the power generation device 4 and the input power from the power system 5 to the power conversion circuit 20, but in the system input quantitative control, The power conversion circuit 20 is controlled so that power is input from the system 5 to the power conversion circuit 20 under a constant system input reference condition.

In the system input quantitative control, the control unit 23 supplies power to the DC load 8 by using the power storage device 3, the power generation device 4, and the power system 5 in combination. In the system input quantitative control, the power system 5 and the power generation device 4 are used as a power supply device, the DC load 8 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device. Therefore, the power supply device includes a power generation device 4 and a power system 5 used as a power supply device. The supplied power is the total of the generated power that is the power supplied from the power generation device 4 and the power supply power (input power) that is the power obtained from the power supply device (power system 5). The demand power is power consumed by the DC load 8 (power consumption).

In the system input quantitative control, the control unit 23 (comparison unit 231) uses the total value of the input power (input power amount) of the power system 5 and the generated power (generated power amount) of the power generation device 4 as the power consumption of the DC load 8. Compare with (Power consumption).

If the supplied power (total of input power and generated power) is greater than the demand power (power consumption), the control unit 23 (instruction unit 233) stores the surplus of the supplied power (total of input power and generated power) in the power storage device. The power conversion circuit 20 is caused to execute output processing (charging power conversion of the power conversion unit 21B) so as to be supplied to 3 (power auxiliary device).

Specifically, the control unit 23 (instruction unit 233) instructs the power conversion unit 21B (charging power so that charging power corresponding to the difference between the total value of input power and generated power and power consumption is obtained. Target value). For example, if the generated power is 13 kW · s and the input power is 10 kW · s, the supplied power is 23 kW · s. At this time, if the power consumption is 20 kW · s, the control unit 23 gives 3 kW · s to the power conversion unit 21B as the target value of the charging power.

If the supplied power (the sum of the input power and the generated power) is less than the demand power (power consumption), the control unit 23 (the instruction unit 233) has a shortage of the supplied power (the total of the input power and the generated power). The power conversion circuit 20 is caused to execute input processing (discharge power conversion of the power conversion unit 21B) so as to be supplemented with power from 3 (power auxiliary device).

Specifically, the control unit 23 (instruction unit 233) instructs the power conversion unit 21B (discharge power) so as to obtain discharge power corresponding to the difference between the total value of input power and generated power and power consumption. Target value). For example, if the power generation amount is 6 kW · s and the input power amount is 10 kW · s, the supplied power amount is 16 kW · s. At this time, if the power consumption is 20 kW · s, the control unit 23 gives 4 kW · s to the power conversion unit 21B as the target value of the discharge power.

Thus, in this system input quantitative control, when the total power amount of the generated power amount of the power generator 4 and the input power amount from the power system 5 to the power conversion circuit 20 is smaller than the power consumption amount of the DC load 8, these When the total power amount is larger than the power consumption amount of the DC load 8 so that the shortage power (shortage power amount) corresponding to the difference between the power storage devices 3 is discharged from the power storage device 3, the surplus power corresponding to these differences Based on the input / output power information, the control unit 23 controls the power conversion circuit 20 so that the power storage device 3 is charged with (the surplus power amount).

The system input reference condition is a condition for designating an input power amount from the power system 5 to the power conversion circuit 20 or a current value and a voltage value depending on the input power amount, and the control unit 23 freely sets the system input reference condition. Can be determined. The system input reference condition may be a condition for designating only one of the current value and the voltage value depending on the input power amount from the power system 5 to the power conversion circuit 20. Here, the system input reference condition specifies that power input from the power system 5 to the power conversion circuit 20 is performed at a constant system reference power amount (system input / output reference power amount) P _SREF. To do.

In the system input quantitative control, the power flow between the power conversion circuit 20 and the power system 5 is limited from the power system 5 to the power conversion circuit 20, and therefore the system input / output command quantity P _S ^{* is changed} to the system input command quantity P _S ^*. Also say.

In the system input quantitative control, the control unit 23 gives the system input command amount P _S ^* into which the value of the system reference power amount P _SREF is assigned to the power conversion unit 21S, so that the power system 5 sends the power conversion unit 21S to the power conversion unit 21S. Thus, the power of the grid reference power amount P _SREF can be input.

Also here, for the sake of concrete explanation, consider that P _SREF = 10. Further, although the power consumption of the DC load 8 can fluctuate, it is assumed here that the power consumption of the DC load 8 is always 20 kW · s. When P _SREF = 10 in the system input quantitative control, the control unit 23 can substitute 10 for the system input command amount P _S ^* , and thereby the input power amount from the power system 5 becomes 10 kW · s.

In this case, for example, as shown in FIG. 16 (a), if the power generation amount of the power generation device 4 is 6 kW · s, the total power amount is less than the power consumption amount 20 kW · s of the DC load 8, The control unit 23 controls the power conversion unit 21 B so that the insufficient power amount 4 kW · s corresponding to the difference is discharged from the power storage device 3.

On the other hand, for example, as shown in FIG. 16 (b), if the power generation amount of the power generation device 4 is 13 kW · s, the total power amount is larger than the power consumption amount 20 kW · s of the DC load 8; The control unit 23 controls the power conversion unit 21B so that the power storage device 3 is charged with a surplus power amount 3 kW · s corresponding to the difference.

As described above, in the grid input quantitative control, the power conversion circuit is connected to the power generated by the power generator 4 and the power grid 5 while absorbing the shortage or surplus of the power generated by the power generator 4 by charging or discharging the power storage device 3. In order to supply power to the DC load 8 using the input power to 20, power is input from the power system 5 to the power conversion circuit 20 under a certain system input reference condition.

However, in the system input quantitative control, as shown in FIG. 16 (c), when the total electric power has a value in the vicinity of the electric power consumption of the DC load 8, between the shortage state and the surplus state of the generated power. Switching between input and output of power between the power conversion circuit 20 and the power storage device 3 (switching between charge and discharge) occurs repeatedly in a relatively short period. Such switching at the time of executing the system input quantitative control is also a storage-side hunting phenomenon.

(4-2) Storage side hunting detection processing HD _1D
During the execution period of the system input quantitative control, the control unit 23 can execute the power storage side hunting detection process HD _1D . The power storage side hunting detection process HD _1D is the same as the power storage side hunting detection process HD _1C described above.

(4-3) Storage-side hunting prediction processing HP _1D
Further, during the execution period of the system input quantitative control, the control unit 23 may predict the occurrence of the power storage side hunting phenomenon by performing the power storage side hunting prediction process HP _1D based on the input / output power information.

For example, in the power storage side hunting prediction process HP _1D , the control unit 23 generates power based on the current value I _G and the voltage value V _G (that is, based on the generated power amount P _G ) or based on the current value I _GINT and the voltage value V _INT. 'seeking, electric energy P _G' power amount P _G corresponding to the amount of power P _G total electric energy of the power system reference power P _SREF which is defined by the system input reference condition (P _G '+ P _SREF ) Is compared with the power consumption of the DC load 8.

The amount of power P _G ′ is the amount of power output from the power converter 21G, and can be considered to be equal to the product (I _GINT × V _INT ). Here, it is considered that the power of the grid reference power amount P _SREF (= 10) is supplied from the power conversion unit 21S to the DC load 8 by the grid input quantitative control. Therefore, the total amount of power (P _G ′ + P _SREF ) is the total amount of power output from the

power conversion units

21G and 21S based on the generated power of the power generation device 4 and the commercial AC power from the power system 5 (power conversion If the power loss of the circuit 20 is ignored, P _G ′ + P _SREF = P _G + P _S ).

Then, the control unit 23 determines _{whether or not} the absolute value of the difference between the total power amount (P _G '+ P _SREF ) and the power consumption amount of the DC load 8 is equal to or less than a predetermined positive threshold value TH _7A. When the state where the value is equal to or less than the threshold TH _7A is continuously observed for a predetermined time or more, the power storage side hunting prediction determination is made.

That is, the control unit 23 (determination unit 232) determines the absolute value of the difference between the supplied power (the total value of the grid reference power amount P _SREF and the power amount P _G ′) and the demand power (power consumption amount P _C8 ) | It is determined whether or not P _SREF + P _G ′ −P _C8 | is equal to or less than a determination value (threshold TH _7A ), and it is determined that the absolute value | P _SREF + P _G ′ −P _C8 | is equal to or less than the determination value TH _7A . The event is configured to determine that an event has occurred.

The control unit 23 (determination unit 232) determines the absolute value of the difference between the supplied power (the total value of the grid reference power amount P _SREF and the power amount P _G ′) and the demand power (power consumption amount P _C8 ). When it is determined whether P _SREF + P _G ′ −P _C8 | is equal to or less than the determination value (threshold value TH _7A ) continues for the determination time (the predetermined time described above), and it is determined that the state is under the determination time It may be configured to determine that an event has occurred.

(4-4) Hunting suppression control CNT _1D
When the storage side hunting detection determination or the storage side hunting prediction determination is made during the execution period of the system input quantitative control, the control unit 23 sets the input power amount from the power system 5 to the power conversion circuit 20 as the system input reference condition. The hunting suppression control CNT _1D that is changed from the system reference power amount P _SREF is executed.

In the hunting suppression control CNT _1D , the absolute value of the input / output power amount between the power conversion circuit 20 and the power storage device 3 is increased by changing the input power amount from the power system 5 to the power conversion circuit 20, thereby storing the power. Suppresses side hunting phenomenon. The suppression control CNT _1D is control performed in the system input quantitative control, and the contents of the system input quantitative control are corrected during the execution period of the suppression control CNT _1D .

That is, the control unit 23 (instruction unit 233) is configured to execute the hunting suppression control CNT _1D when it is determined that an event has occurred during the execution period of the system input quantitative control. In the hunting suppression control CNT _1D , the control unit 23 (instruction unit 233) is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

A first implementation example of the suppression control CNT _1D will be described. Before the storage-side hunting recognition timing, as described above, the control unit 23 substitutes the system reference power amount P _SREF for the system input command amount P _S ^* , whereby the input power amount from the power system 5 is This is consistent with the reference power amount P _SREF (= 10) (see FIGS. 16A, 16B, and 16C).

However, when the storage-side hunting detection determination or the storage-side hunting prediction determination is made, in the first implementation example of the suppression control CNT _1D , the control unit 23 reduces the system input command amount P _S ^* to the system by a predetermined amount ΔP _S ^*. The reference power amount P _{SREF is} increased or decreased (that is, the system input command amount P _S ^* is changed with reference to the power storage side hunting recognition timing).

That is, the control unit 23 (instruction unit 233) is configured to execute normal control for setting the target value to a predetermined value (system reference power amount P _SREF ) until it is determined that an event has occurred. In the hunting suppression control CNT _1D , the control unit 23 is configured to set the target value to a value (P _SREF ± ΔP _S ^* ) different from the predetermined value (system reference power amount P _SREF ).

As described above, in the first implementation example, the control unit 23 (instruction unit 233) increases or decreases the input power so that the difference between the total value of the input power and the generated power and the power consumption increases.

FIG. 17A shows a power input / output state when the system input command amount P _S ^* is increased by 2 from the system reference power amount P _SREF (= 10).

In this state, the control unit 23 converts the power storage unit 3 so that the power storage device 3 is charged with a surplus power amount 2 kW · s corresponding to the difference between the power generation amount of the power generation device 4 and the system input command amount P _S ^*. 21B is controlled. That is, the input / output between the power conversion circuit 20 and the power storage device 3 is based on the increase in the amount of input power from the power system 5 due to the suppression control CNT _1D with reference to the state before the increase (based on the state of FIG. 16C). The absolute value of the electric energy increases. As a result, the power storage side hunting phenomenon is appropriately suppressed. The same applies when the system input command amount P _S ^* is decreased from the system reference power amount P _SREF .

In this state, the control unit 23 converts the power so that an insufficient power amount 2 kW · s corresponding to the difference between the total value of the input power and the generated power and the power consumption is input from the power storage device 3 to the power conversion circuit 20. The unit 21B is controlled. As a result, the power storage side hunting phenomenon is appropriately suppressed.

Thus, in the first implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is the target value of the power supply power (input power). That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21S.

A second implementation example of the suppression control CNT _1D will be described. When the storage-side hunting detection determination or the storage-side hunting prediction determination is made, the control unit 23 that performs the second implementation example of the suppression control CNT _1D uses the charging command to the power conversion unit 21B with reference to the timing before the storage-side hunting recognition timing. The suppression control CNT _1D is realized by changing the amount or the discharge command amount P _B ^* by a predetermined amount ΔP _B ^* and assigning the change amount to the change in the input power amount from the power system 5 to the power conversion circuit 20.

That is, in the normal control, the control unit 23 (instruction unit 233) can obtain discharge power or charge power corresponding to a difference between supply power (total value of input power and generated power) and demand power (power consumption). In this manner, an instruction (a target value of discharge power or charge power) is given to the power conversion unit 21B. In contrast, in the hunting suppression control CNT _1D , the control unit 23 (instruction unit 233) maintains the target value (discharge power or charge power target value) given to the power conversion unit 21B at a predetermined value. That is, the control unit 23 performs either the input process or the output process on the power conversion unit 21B regardless of the difference between the supplied power (the total value of the input power and the generated power) and the demand power (power consumption). Let it be done.

For example, in the state of FIG. 16C, that is, the state in which the amount of power generated by the power generation device 4 and the amount of input power from the power system 5 are both 10 kW · s, as shown in FIG. This corresponds to a state where zero is substituted for the discharge command amount) P _B ^* .

In this state, when the storage-side hunting detection determination or the storage-side hunting prediction determination is made, the control unit 23 executes, for example, suppression control CNT _1D that changes the charge command amount P _B ^* from zero to 2. Can do.

In the second implementation example of the suppression control CNT _1D , the control unit 23 prioritizes the charge command amount (or discharge command amount) P _B ^* over the system input command amount P _S ^* or the system input command amount P _S. ^* Is not given to the power converter 21S. In any case, in the suppression control CNT _1D , the control unit 23 supplies an insufficient power amount (supplied to the DC load 8) determined by the power generation amount of the power generation device 4, the charging power amount of the power storage device 3, and the power consumption amount of the DC load 8. The power converter 21S is controlled so that the power shortage) is input from the power system 5.

In this case, the amount of generated power is 10 kW · s, but the power storage device 3 is supplied with 2 kW · s of charging power. Therefore, when the power consumption is 20 kW · s, the shortage of the power consumption is 12 kW · s. Therefore, the control unit 23 (instruction unit 233) increases the system input command amount P _S ^* from the system reference power amount P _SREF (= 10 kW · s) to 12 kW · s. That is, the control unit 23 gives 12 kW · s as a target value to the power conversion unit 21S. As a result, as shown in FIG. 18, 12 kW · s of power is input from the power system 5 to the power conversion circuit 20. This state is equivalent to the state shown in FIG.

Figure 18 is an example of when the charging of power storage device 3 has changed the command amount P _B ^* to take place, even by changing the command value P _B ^* as discharge of the power storage device 3 is carried out In that case, the amount of input power from the power system 5 is reduced from 10 kW · s.

For example, the control unit 23 can execute the suppression control CNT _1D that changes the discharge command amount (target value of discharge power) P _B ^* from zero to a predetermined value (for example, 2).

In this case, the amount of generated power is 10 kW · s, but 2 kW · s of discharge power is supplied from the power storage device 3. Therefore, when the power consumption is 20 kW · s, the shortage of the power consumption is 8 kW · s. Therefore, the control unit 23 (instruction unit 233) decreases the system input command amount P _S ^* from the system reference power amount P _SREF (= 10 kW · s) to 8 kW · s. That is, the control unit 23 gives 8 kW · s as a target value to the power conversion unit 21S. As a result, an input power of 8 kW · s, which is smaller than the grid reference power amount P _SREF, is output from the power grid 5.

Thus, in the second implementation example, the instruction given from the control unit 23 (instruction unit 233) to the power conversion circuit 20 is the target value of the discharge power or the charge power. That is, the control unit 23 (instruction unit 233) suppresses the hunting phenomenon by controlling the power conversion unit 21B.

In the first implementation example of the suppression control CNT _1D , the input power amount from the power system 5 is directly controlled by controlling the system input command amount P _S ^* , whereas in the second implementation example of the suppression control CNT _1D , The amount of input power from the power system 5 is indirectly controlled by controlling the charge or discharge command amount P _B ^* (by controlling the amount of input / output power between the power conversion circuit 20 and the power storage device 3).

(4-5) cancellation determination processing J _1D corresponding to suppression control CNT _1D
Control unit 23, during the execution period of the suppression control CNT _1D, through a success determination of the predetermined release condition, release determination processing J _1D be performed determines whether to cancel the execution of the suppression control CNT _1D Can do.

For example, in the cancelability determination process J _1D , the control unit 23 _{obtains the} total power amount (P _G '+ P _SREF ) by the above-described method, and _calculates the total power amount (P _G ' + P _SREF ) and the power consumption amount of the DC load 8. Is obtained (if the power loss of the power conversion circuit 20 is ignored, P _G ′ + P _SREF = P _G + P _S ).

In the determination process J _1D , the control unit 23 continues the state where the absolute value is equal to or greater than the predetermined positive threshold TH _8A or the absolute value is equal to or greater than the threshold TH _8A for a predetermined time or longer. When observed, or when a state in which the absolute value is positive is continuously observed for a predetermined time or more, it is determined that the release condition in the determination process J _1D is satisfied (execution of the suppression control CNT _1D is executed). It is determined that the storage-side hunting phenomenon does not occur or is unlikely to occur even when the release is canceled), and the execution of the suppression control CNT _1D is canceled. By canceling the execution of the suppression control CNT _1D , the input power amount from the power system 5 returns to the system reference power amount P _SREF (= 10).

That is, during the execution of the hunting suppression control CNT _1D , the control unit 23 _calculates the total value (P _G '+ P _SREF ) of the generated power P _G ' and the predetermined value (system reference power amount) P _SREF and the demand power (power consumption). When the difference (P _G '+ P _SREF -P _C8 ) from the amount P _C8 ) satisfies the release condition, the hunting suppression control CNT _1D is terminated. The release condition is that the absolute value of the difference | P _G ′ + P _SREF −P _C8 | is greater than or equal to the threshold TH _8A , and the absolute value of the difference | P _G ′ + P _SREF −P _C8 | is greater than or equal to the threshold TH _8A. Continued for a predetermined first time (for example, the above-mentioned predetermined time), and a state in which the difference (P _G '+ P _SREF -P _C8 ) is positive or negative continues for a predetermined second time (for example, the above-mentioned predetermined time) Either

For example, during the execution of the hunting suppression control CNT _1D , the determination unit 232 includes the total value (P _G ′ + P _SREF ) of the generated power P _G ′ and the predetermined value (system reference power amount) P _SREF and the demand power (power consumption). An end determination is made as to whether or not the difference (P _G ′ + P _SREF −P _C8 ) from the amount P _C8 ) satisfies the release condition, and the result of the end determination is given to the instruction unit 233. The instruction unit 233 is configured to end the hunting suppression control CNT _1D if the end determination result indicates that the release condition is satisfied.

Alternatively, for example, when the system input command amount P _S ^* is decreased from the system reference power amount P _SREF by a predetermined amount ΔP _S ^* by the suppression control CNT _1D , the control unit 23 determines the difference (P _C8 − (P _G '+ P _S ^* )) may be set as a determination target, and when the system input command amount P _S ^* is increased from the system reference power amount P _SREF by a predetermined amount ΔP _S ^* by the suppression control CNT _1D. The control unit 23 may set the difference ((P _G ′ + P _S ^* ) − P _C8 ) as a determination target.

In the determination target, P _S ^* may be replaced with the actually measured input power P _S (ie, I _S × V _S ). As described above, P _C8 represents the power consumption of the DC load 8. Then, when the determination target is equal to or greater than a predetermined positive threshold TH _8A ′, or when a state where the determination target is equal to or greater than the threshold TH _8A ′ is continuously observed for a predetermined time or longer, the control unit 23 The execution of the suppression control CNT _1D may be canceled by determining that the cancellation condition in the determination process J _1D is satisfied (TH _8A '> ΔP _S ^* ).

The control unit 23 determines that the difference between the supply power (the total amount of generated power and the input power) and the demand power (power consumption) satisfies the release condition during execution of the hunting suppression control CNT _1D. The hunting suppression control CNT _1D may be configured to end.

In this case, the cancellation condition is that the absolute value of the difference between the total value of the generated power amount and the input power amount and the consumed power amount is equal to or less than a predetermined threshold, or the total value of the generated power amount and the input power amount That is, a state where the absolute value of the difference between the power consumption and the power consumption amount is equal to or less than a predetermined threshold value continues for a predetermined time. The predetermined threshold value is smaller than the change width of the difference between the total value of the generated power amount and the input power amount and the consumed power amount due to the execution of the hunting suppression control CNT _1D . Alternatively, the release condition may be that a state where the difference between the total value of the generated power amount and the input power amount and the consumed power amount is positive or negative continues for a predetermined time.

Alternatively, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed a predetermined number of times during the execution of the hunting suppression control CNT _1D , and if it is determined that the switching operation has been performed the predetermined number of times, The suppression control CNT _1D may be configured to end. The predetermined number may be one or more.

3. Operation Flowchart Next, an operation flow of the power conversion device 2 will be described with reference to FIG. FIG. 19 is an operation flowchart of the power conversion device 2 focusing on the above-described various quantitative controls.

First, in step S11, the control unit 23 starts execution of the above-described charge quantitative control, discharge quantitative control, system output quantitative control, or system input quantitative control (hereinafter, charge quantitative control, discharge quantitative control, system output quantitative control). Alternatively, system input quantitative control is also simply referred to as quantitative control).

Thereafter, in step S12, the control unit 23, based on the input / output power information, performs the above-mentioned system side or power storage side hunting detection process (HD _1A , HD _1B , HD _1C , HD _1D ) or system side or power storage side hunting prediction process. (HP _1A , HP _1B , HP _1C , HP _1D ).

In subsequent step S13, the control unit 23 checks whether the system side or power storage side hunting detection determination or the system side or power storage side hunting prediction determination has been made, and if neither of these determinations has been made. Returning from step S13 to step S12, the processes of steps S12 and S13 are repeated, but if any of these determinations is made, a transition to step S14 is generated and hunting suppression control (CNT _1A , CNT _1B , CNT _1C , CNT _1D ) is started.

After the execution of the hunting suppression control is started, the control unit 23 performs a hunting suppression control cancelability determination process (J _1A , J _1B , J _1C , J _1D ) (step S15).

The control unit 23 continues to execute the hunting suppression control until a predetermined release condition is satisfied (steps S15 and S16), and cancels the execution of the hunting suppression control when the release condition is satisfied (step S17). Return to step S12.

As described above, the hunting suppression control is a control that is performed in the quantitative control and modifies the content of the quantitative control (for example, if the hunting suppression control is performed during the execution of the charge quantitative control, the charging power The charge quantitative control is performed after the amount is corrected upward or downward from the reference power amount P _BREF for power storage), and when the execution of the hunting suppression control is canceled, the correction is also canceled and the basic quantitative control is performed. Resumed.

However, the execution of the quantitative control is stopped during the execution of the hunting suppression control, and the quantitative control can be resumed when the hunting suppression control is canceled (in this case, the hunting suppression control is canceled in step S17). Then, the process returns to step S11).

In addition, when there is a possibility that the reference power amount P _BREF or P _SREF is changed during execution of the hunting suppression control, when the hunting suppression control is canceled, the reference power amount P _BREF or P _SREF is updated to the latest one. It is good to update to. Alternatively, if the reference power P _BREF or P _SREF is changed at any timing, the reference power P _BREF or P _SREF with updated to the latest ones may be returned to step S11.

Moreover, the control part 23 may perform the cancellation | release permission determination processing _J1A , _J1B , _J1C, or _J1D as follows.

That is, during the execution period of the suppression control CNT _1A or CNT _1B , the control unit 23 executes the system-side hunting detection process HD _1A and observes the occurrence of the system-side hunting phenomenon for a predetermined number of times (any number of 1 or more). When it is determined that the release condition is satisfied, the execution of the suppression control CNT _1A or CNT _1B may be released.

Similarly, during the execution period of the suppression control CNT _1C or CNT _1D , the control unit 23 executes the storage-side hunting detection process HD _1C, and the occurrence of the storage-side hunting phenomenon is equal to or greater than a predetermined number (any number of 1 or more). When the observation is observed, it may be determined that the release condition is satisfied, and the execution of the suppression control CNT _1C or CNT _1D may be released.

逆 If an increase in the amount of generated power occurs during execution of suppression control, a hunting phenomenon may occur. In such a case, the release of the suppression control contributes to avoiding the hunting phenomenon.

4). Features of Power Converter 2 of the Present Embodiment The power converter 2 of the present embodiment has the following first features. In the first feature, the power conversion device 2 includes a power conversion circuit 20 and a control unit 23. The power conversion circuit 20 includes a power storage side circuit (power conversion unit 21B) connected to the power storage device 3 that can be charged and discharged, and a power generation side circuit (power) connected to the power generation device 4 that generates power and outputs generated power. It has a system side circuit (power conversion unit 21S) connected to the conversion unit 21G) and the power system 5. The power conversion circuit 20 is configured to perform power transmission and reception between the power storage device 3, the power generation device 4, and the power system 5 through power conversion. The control unit 23 is configured to control power transmission and power reception by controlling the power conversion circuit 20. The control unit 23 absorbs the shortage or surplus of the generated power at the input / output of the power between the power conversion circuit 20 and the power system 5 and uses the generated power of the power generation device 4 to keep the power storage device 3 at a certain level. A power storage device that is charged under one reference condition or that supplies power to at least one of a load and a secondary battery connected to the power conversion circuit 20 using the generated power of the power generation device 4 and the discharge power of the power storage device 3 3 is configured to execute quantitative control (charge quantitative control / discharge quantitative control) for discharging 3 under a constant second reference condition. In the quantitative control, when switching of power input / output between the power conversion circuit 20 and the power system 5 is detected a predetermined number of times within a predetermined time, or a value corresponding to the generated power amount or the generated power amount of the power generation device 4 When the occurrence of switching is predicted based on the first reference condition or the second reference condition, the control unit 23 changes the charging or discharging condition of the power storage device 3 from the first reference condition or the second reference condition. The suppression control which suppresses switching by this is performed.

The power conversion device 2 of the present embodiment has the following second feature in addition to the first feature. In the second feature, the power storage circuit (power conversion unit 21B) includes the power conversion circuit 20 and the power storage device 3 so that the charging or discharging condition of the power storage device 3 follows the charge / discharge command amount given from the control unit 23. It is configured to perform power conversion between. When detection or prediction is made in the quantitative control, the control unit 23 realizes the suppression control by changing the charge / discharge command amount from the reference amount according to the first reference condition or the second reference condition.

The power conversion device 2 of the present embodiment has the following third feature in addition to the first feature. In the third feature, the system side circuit (power conversion unit 21S) is configured so that the power input / output conditions between the power conversion circuit 20 and the power system 5 are in accordance with the system input / output command amount given from the control unit 23. Power conversion between the power conversion circuit 20 and the power system 5 is executed. When the detection or prediction is made in the quantitative control, the control unit 23 changes the system input / output command amount with reference to the time before the detection or prediction is made, and the power amount corresponding to the change is stored in the power storage device 3. Suppression control is realized by allocating to a change in the amount of charge power or the amount of discharge power.

Further, the power conversion device 2 of the present embodiment has a fourth feature. In the fourth feature, the power conversion device 2 includes a power conversion circuit 20 and a control unit 23. The power conversion circuit 20 includes a power storage side circuit (power conversion unit 21B) connected to the power storage device 3 that can be charged and discharged, and a power generation side circuit (power) connected to the power generation device 4 that generates power and outputs generated power. It has a system side circuit (power conversion unit 21S) connected to the conversion unit 21G) and the power system 5. The power conversion circuit 20 is configured to perform power transmission and reception between the power storage device 3, the power generation device 4, and the power system 5 through power conversion. The control unit 23 is configured to control power transmission and power reception by controlling the power conversion circuit 20. The control unit 23 absorbs the shortage or surplus of the generated power by charging or discharging the power storage device 3, and uses the generated power of the power generation device 4 to transfer a constant first reference from the power conversion circuit 20 to the power system 5. Power is output under conditions, or power is supplied to at least one of a load and a secondary battery connected to the power conversion circuit 20 using generated power and input power from the power system 5 to the power conversion circuit 20 Therefore, the quantitative control (system output quantitative control / system input quantitative control) is performed in which power is input from the power system 5 to the power conversion circuit 20 under a constant second reference condition. In the quantitative control, when switching of power input / output between the power conversion circuit 20 and the power storage device 3 is detected a predetermined number of times or more within a predetermined time, the generated power amount of the power generation device 4 or a value corresponding to the generated power amount When occurrence of switching is predicted based on the first reference condition or the second reference condition, the control unit 23 sets the input / output condition of power between the power conversion circuit 20 and the power system 5 as the first reference condition or the second reference condition. Suppression control that suppresses switching by changing from the reference condition is executed.

The power conversion device 2 of the present embodiment has the following fifth feature in addition to the fourth feature. In the fifth feature, the system side circuit (power conversion unit 21S) is configured so that the power input / output conditions between the power conversion circuit 20 and the power system 5 are in accordance with the system input / output command amount given from the control unit 23. Power conversion between the power conversion circuit 20 and the power system 5 is executed. When detection or prediction is performed in the quantitative control, the control unit 23 realizes the suppression control by changing the system input / output command amount from the reference amount according to the first reference condition or the second reference condition.

The power conversion device 2 of the present embodiment has the following sixth feature in addition to the fourth feature. In the sixth feature, the power storage circuit (power conversion unit 21B) includes the power conversion circuit 20 and the power storage device 3 so that the charge or discharge conditions of the power storage device 3 are in accordance with the charge / discharge command amount given from the control unit 23. Power conversion between the two. When detection or prediction is made in the quantitative control, the control unit 23 changes the charge / discharge command amount with reference to the time before detection or prediction is made, and converts the amount of power corresponding to the change to the power conversion circuit 20 and Suppression control is realized by allocating to changes in the input / output power amount between power systems.

The power conversion device 2 of the present embodiment has the following seventh feature in addition to any one of the first to sixth features. In the seventh feature, the control unit 23 determines a predetermined value based on the generated power amount of the power generation device 4 or a value corresponding to the generated power amount and the first reference condition or the second reference condition during the execution period of the suppression control. When it is determined that the release condition is satisfied, the execution of the suppression control is released.

The power conversion device 2 of the present embodiment has the following eighth feature in addition to any one of the first to sixth features. In the eighth feature, the control unit 23 cancels the execution of the suppression control when switching is detected during the execution period of the suppression control.

In addition, the power converter device 2 should just have at least 1 of the 1st characteristic and the 4th characteristic. The second, third, fifth to eighth features are optional features.

As described above, according to the hunting suppression control CNT ₁ according to the present embodiment, the system side hunting phenomenon that affects the stability of the power system 5 or the power storage side hunting phenomenon that may adversely affect the power storage device 3 is performed. It is possible to suppress appropriately. Therefore, according to the present embodiment, it is possible to provide the power conversion device 2 that contributes to suppression of the hunting phenomenon.

When realizing the hunting suppression control CNT ₁ , the same hunting suppression effect can be obtained regardless of which of the first and second implementation examples described above (see, for example, FIGS. 6A and 6C).

Further, a method for releasing the hunting suppression control CNT ₁ when monitoring the fulfillment whether cancellation condition when the execution hunting suppression control CNT _1, the hunting phenomenon is determined to not or hardly occur occur even cancel the execution By adopting, charging or the like can be performed with as much original power as possible while avoiding the hunting phenomenon as much as possible.

Note that, when the hunting detection process is used without using the hunting prediction process, the hunting suppression control is executed after the occurrence of the hunting phenomenon is detected, so that some hunting phenomenon is allowed to occur. On the other hand, if the hunting prediction process is used, the occurrence of the hunting phenomenon can be completely or almost completely avoided. However, when the hunting prediction process is used, the time for performing charging or the like with the original amount of power is shorter than when the hunting detection process is used. Whether to execute the hunting detection process or the prediction process may be set in accordance with which one of priority is given to the suppression of the hunting phenomenon and the charging with the original electric energy.

(Second Embodiment)
1. Configuration of Power Converter 2 of Second Embodiment The power converter 2 of the present embodiment includes first, sixth to tenth, sixteenth to eighteenth, twenty-first, twenty-second, twenty-fifth to twenty-fifth according to the present invention. The power conversion device 2 in the form of 28 is related.

Hereinafter, a second embodiment of the present invention will be described. The second embodiment and the third embodiment which will be described later are embodiments based on the first embodiment. The matters not particularly described in the second and third embodiments are the same as those of the first embodiment as long as there is no contradiction. The description also applies to the second and third embodiments.

The configuration of the power supply system 1 according to the second embodiment is the same as the configuration of the power supply system 1 according to the first embodiment (see FIG. 1).

Further, the power supply device 2 of the present embodiment includes a power conversion circuit 20 and a control unit 23 as in the case of the power supply device 2 of the first embodiment.

The power conversion circuit 20 includes a power receiving function that receives power from the power supply device, a power transmission function that supplies power to the power demand device, an output process that supplies power to the power auxiliary device, and an input process that acquires power from the power auxiliary device. And adjusting at least one of an input / output selection function for selectively executing and supply power that is power received from the power supply device and demand power that is power supplied to the power demanding device in accordance with an instruction from the control unit 23 An adjustment function.

The control unit 23 compares the supplied power with the demand power, and if the supplied power is greater than the demand power, causes the power conversion circuit 20 to execute an output process so that a surplus of the supplied power is supplied to the power auxiliary device. Is less than the demand power, the power conversion circuit 20 is configured to execute the input process so that the shortage of the supplied power is compensated by the power from the power auxiliary device.

The control unit 23 is configured to determine whether or not an event that causes a hunting phenomenon has occurred in the power conversion circuit 20, and to execute hunting suppression control when determining that an event has occurred.

In the hunting suppression control, the control unit 23 is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

Although not particularly conscious in the first embodiment, in the second embodiment, the first embodiment described above and the third embodiment described later, the control unit 23 performs maximum power point tracking control (Maximum Power) for the power generation device 4. Point Tracking Control; hereinafter referred to as MPPT control).

A curve 400 in FIG. 20 represents the relationship between the output current of the power generation device 4 and the generated power. The value of the output current of the power generator 4 is the above-described current value I _G , and the amount of power generated by the power generator 4 is the above-described power amount P _G (= I _G × V _G ) (see FIG. 1).

In the power generation device 4, the generated power changes depending on the output current. When the output current value I _G coincides with the current value I _MPP , the generated power amount P _G becomes maximum (that is, becomes the maximum power amount P _MPP ), and the generated power increases as the absolute value | I _G −I _MPP | increases. the amount P _G decreases from the maximum amount of power P _MPP.

The point on the curve 400 that defines the amount of power generated by the power generation device 4 is called a power point (or operating point). The power point 401 is a power point that makes the generated power amount of the power generation device 4 coincide with the maximum power amount P _MPP . On the other hand,

power point

402 and 403 are power point to match the small amount of power P _Q than the maximum amount of power P _MPP the generated power of the generator 4. At

power points

402 and 403, current value I _G assumes values I _Q1 and I _Q2 , respectively. Here, “0 0).

As shown in FIG. 21, the control unit 23 generates a current command value I _G ^* that specifies the current value I _G can be given to the power conversion unit 21G, whereby it is possible to control the current value I _G together, it is possible to control the voltage value V _G and the amount of power P _G through control of the current value I _G.

Power conversion unit 21G generates power for power conversion so that the current value I _G matches the current command value I _G ^*. When performing the MPPT control, the control unit 23 sets the current command value I _G ^* so that the power generation amount of the power generation device 4 is maximized based on the current value I _G and the voltage value V _G included in the input / output power information. Set and adjust. That is, when executing the MPPT control, the control unit 23 substitutes the value I _MPP for the current command value I _G ^* . Since the implementation method of MPPT control is well-known, it abbreviate | omits description.

That is, the control unit 23 is configured the target value of the generated power P _G as an indication to provide a power conversion circuit 20.

Power conversion circuit 20 receives the target value (the target value of the generated power P _G), configured to generated power P _G to control the power generator 4 so that the target value. For example, the power conversion unit 21G of the power conversion circuit 20 receives the target value of the generated power P _G from the control unit 23 is configured to generated power P _G to control the power generator 4 so that the target value .

In the present embodiment, the power generation device 4 is a solar cell. Power conversion circuit 20 is configured to adjust the generated power P _G by changing the operating point of the solar cell (power point) according to the instruction.

The control unit 23 is configured to execute normal control for setting a target value to a default value until it is determined that an event has occurred. The default value is a value corresponding to the maximum power of the solar cell.

On the other hand, also in the second embodiment, the control unit 23 can individually execute the charge quantitative control, the discharge quantitative control, the system output quantitative control, and the system input quantitative control described in the first embodiment. At this time, the control unit 23 can execute charge quantitative control, discharge quantitative control, system output quantitative control, or system input quantitative control while performing MPPT control (the same applies to the first and third embodiments).

In charge quantitative control, the power generation device 4 is used as a power supply device, the power storage device 3 is used as a power demand device, and the power system 5 is used as a power auxiliary device. Therefore, the supplied power is generated power from the power generation device 4. The demand power is charging power for the power storage device 3.

In the discharge quantitative control, the power generation device 4 and the power supply device (power storage device 3) are used as a power supply device, the DC load 8 is used as a power demand device, and the power system 5 is used as a power auxiliary device. Therefore, the supplied power is the sum of the generated power from the power generation device 4 and the power supply power (discharge power of the power storage device 3) that is power obtained from the power supply device. The demand power is the power consumption of the DC load 8.

In the grid output quantitative control, the power generation device 4 is used as a power supply device, the power system 5 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device. Therefore, the supplied power is generated power from the power generation device 4. The demand power is output power to the power system 5.

In the grid input quantitative control, the power generation device 4 and the power supply device (power system 5) are used as a power supply device, the DC load 8 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device. Accordingly, the supplied power is the sum of the generated power from the power generation device 4 and the power supply power (input power of the power system 5) that is power obtained from the power supply device. The demand power is the power consumption of the DC load 8.

Also in the second embodiment, the above-mentioned system side or power storage side hunting phenomenon may occur during execution of quantitative control. The control unit 23 can perform hunting detection processing or prediction processing similar to that described in the first embodiment during the execution of each quantitative control. The same applies to a third embodiment described later. That is, the control unit 23 according to the second and third embodiments can perform the above-described hunting detection process HD _1A or the prediction process HP _1A during the execution period of the MPPT control and the charge quantitative control. The hunting detection process HD _1B or the prediction process HP _1B can be performed during the execution period of the quantitative control, and the hunting detection process HD _1C or the prediction process HP can be performed during the execution period of the MPPT control and the system output quantitative control. _1C can be performed, and the above-described hunting detection process HD _1D or prediction process HP _1D can be performed during the execution period of MPPT control and system input quantitative control.

2. Details of control 2.1 Hunting suppression control CNT ₂
When system-side hunting detection determination or system-side hunting prediction determination is made during the period in which MPPT control and charge quantitative control or discharge quantitative control are executed, or MPPT control and system output quantitative control or system input quantitative control When the storage-side hunting detection determination or the storage-side hunting prediction determination is made during the period in which the power generation device 4 is executed, the control unit 23 changes the power generation amount of the power generation device 4 through the change of the power point of the power generation device 4. Hunting suppression control CNT ₂ is executed. That is, the control unit 23, the hunting suppression control CNT _2, arranged to set the default value different target value for generated power P _G.

In the hunting suppression control CNT ₂ applied to charge quantitative control or discharge quantitative control, the absolute value of the input / output power amount between the power conversion circuit 20 and the power system 5 is increased by changing the power generation amount of the power generation device 4. This suppresses the system-side hunting phenomenon.

In the hunting suppression control CNT ₂ applied to the system output quantitative control or the system input quantitative control, the absolute value of the input / output power amount between the power conversion circuit 20 and the power storage device 3 by changing the power generation amount of the power generation device 4. This suppresses the storage-side hunting phenomenon.

Suppression control CNT ₂ is a control performed in each quantitative control, although the execution of the suppression control CNT ₂ does not affect the contents of each quantitative control, the MPPT control during execution of the suppression control CNT ₂ Stopped.

A specific method of the suppression control CNT ₂ will be described. In the following description of the second embodiment, it is assumed that charge quantitative control, discharge quantitative control, system output quantitative control, or system input quantitative control is continuously executed unless otherwise specified.

Prior to the system-side hunting recognition timing or the power storage-side hunting recognition timing, the control unit 23 implements MPPT control by giving a current command value I _G ^* into which the value I _MPP is substituted to the power conversion unit 21G. In this state, power point of the generator 4 is the maximum amount of power P _MPP is outputted to the power conversion unit 21G as generated power P _G is a consistent with power point 401 (see FIG. 20), power generating apparatus 4 .

However, when the system-side hunting detection determination, the system-side hunting prediction determination, the power storage-side hunting detection determination, or the power storage-side hunting prediction determination is performed, in the suppression control CNT ₂ , the control unit 23 supplies the current to the power conversion unit 21G. The command value I _G ^* is changed from the value I _MPP to the value I _Q1 or I _Q2 , thereby changing the power point of the power generator 4 from the power point 401 to the power point 402 or 403 (see FIG. 20). As a result, the power generation amount of the power generation device 4 decreases from the power amount P _MPP to the power amount P _Q.

For example, the control unit 23, the hunting suppression control, corresponding to the target value of the generated power P _G, from the default value corresponding to the power point 401 (electric energy P _MPP), the power point 402 and 403 (power amount P _Q) Change the value to For example, the electric energy P _MPP is 10 kW · s, and the electric energy P _Q is 8 kW · s.

In the case of charge quantitative control, the amount of supplied power (power generation amount) and the amount of demand power (charge power amount) are compared. When the charging power amount of the power storage device 3 is 10 kW · s, the control unit 23 executes the hunting suppression control CNT ₂ , so that the supplied power amount is insufficient by 2 kW · s. Therefore, the difference between the power supply amount and the power demand amount is increased, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as a target value of the input power to the power conversion unit 21S, and thereby obtains input power of 2 kW · s from the power system 5.

In the case of the discharge quantitative control, the supplied power amount (total value of the generated power amount and the discharged power amount) is compared with the demand power amount (power consumption amount). When the discharge power amount of the power storage device 3 is 10 kW · s and the power consumption amount is 20 kW · s, the control unit 23 executes the hunting suppression control CNT ₂ so that the supplied power amount is insufficient by 2 kW · s. It will be. Therefore, the difference between the power supply amount and the power demand amount is increased, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as a target value of the input power to the power conversion unit 21S, and thereby obtains input power of 2 kW · s from the power system 5.

In the case of grid output quantitative control, the amount of power supplied (power generation amount) and the amount of power demand (output power amount) are compared. When the output power amount of the power system 5 is 10 kW · s, the control unit 23 executes the hunting suppression control CNT ₂ , so that the supplied power amount is insufficient by 2 kW · s. Therefore, the difference between the power supply amount and the power demand amount is increased, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as a target value of the discharge power to the power conversion unit 21B, and thereby obtains 2 kW · s of discharge power from the power storage device 3.

In the case of system input quantitative control, the amount of supplied power (the total value of the generated power and the amount of input power) is compared with the amount of demand power (power consumption). When the input power amount of the power system 5 is 10 kW · s and the power consumption amount is 20 kW · s, the control unit 23 executes the hunting suppression control CNT ₂ so that the supplied power amount is insufficient by 2 kW · s. It will be. Therefore, the difference between the power supply amount and the power demand amount is increased, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the discharge power to the power conversion unit 21B, and thereby obtains 2 kW · s of discharge power from the power storage device 3.

As can be easily understood from the description of the first embodiment, when the power generation amount of the power generation device 4 decreases when the system-side hunting phenomenon occurs, the absolute value of the input / output power amount between the power conversion circuit 20 and the power system 5 is reduced. Since the value increases, the system-side hunting phenomenon is appropriately suppressed. Similarly, if the power generation amount of the power generation device 4 decreases when the power storage side hunting phenomenon occurs, the absolute value of the input / output power amount between the power conversion circuit 20 and the power storage device 3 increases, so that the power storage side hunting phenomenon is appropriate. To be suppressed.

2.2 release permission corresponding to the suppression control CNT ₂ determination process J ₂
Control unit 23, during the execution period of the suppression control CNT _2, via the judging success or failure of the predetermined release condition, performing the determining cancellation determination processing J ₂ whether to cancel the execution of the suppression control CNT ₂ Can do.

On the assumption that the charging quantitative control is made for explaining an example of a cancellation determination processing J _2. In release determination processing J _2, the control unit 23, for example, when any of the first to fourth release following conditions are satisfied, it is possible to resume the MPPT control by releasing the execution of the suppression control CNT _2.

The first and second release conditions will be described with reference to FIGS. 22 and 23, solid line curves 411 and 411 'represent a first example and a second example of the time transition of the amount of power generated by the power generation device 4.

Since it is assumed that the charge quantitative control is currently performed, the control unit 23 substitutes the reference power amount P _BREF for power storage into the charge command amount P _B ^* , thereby charging power of the power storage device 3. The amount corresponds to the reference power amount P _BREF for power storage.

The MPPT control is continuously executed until the timing t _B1 is reached. Timing t _B1 is the system-side hunting recognition timing. At timing t _B1 , the control unit 23 starts executing the suppression control CNT ₂ , thereby reducing the generated power amount P _G by ΔP _{G at the} timing t _B1. . Timings t _B2 and t _B2 ′ are timings after timing t _B1 .

During the execution period of the suppression control CNT ₂ , the control unit 23 is based on the current value I _G and the voltage value V _G (that is, based on the generated power amount P _G ) or based on the current value I _GINT and the voltage value V _INT. The charge power amount P _B ′ is obtained. As described above, the charge power amount P _B ′ is the charge power amount based on the generated power amount P _G , and if the power loss amount of power conversion is regarded as zero (that is, if the power conversion efficiency is regarded as 100%), is a P _B '= P _G.

The first release condition is satisfied when the charging power amount P _B ′ satisfying the following inequality (A1) is observed.

That is, the control unit 23 _determines that the difference between the supplied power (charging power amount P _B ′) and the demand power (storage power reference power amount P _BREF ) is canceled during the execution of the hunting suppression control CNT ₂ (first releasing condition). When the condition is satisfied, the hunting suppression control CNT ₂ is configured to end. The first release condition is that a value obtained by subtracting the supplied power (charging power amount P _B ′) from the demand power (storage power reference power amount P _BREF ) is equal to or less than a predetermined threshold TH _B1 . That is, the first release condition is that the absolute value of the difference between the supplied power (charging power amount P _B ′) and the demand power (power storage reference power amount P _BREF ) is equal to or less than a predetermined threshold value TH _B1 .

In the example of FIG. 22, the timing t _B1 and t suppressing control CNT ₂ between _B2 for charging power amount P _B 'does not satisfy the inequality (A1) at each timing between the timing t _B1 and t _B2 is continuously performed However, since the charging power amount P _B ′ at the timing t _B2 satisfies the inequality (A1), the control unit 23 cancels the execution of the suppression control CNT _{2 at} the timing t _B2 and restarts the MPPT control.

If the power conversion loss is ignored, the left side of the equation (A1) _matches (P _BREF −P _G ) or (P _B ^* −P _G ). That is, establishment of formula (A1), the difference between the power storage for reference power P _BREF and ^(* = charge command amount P _B) and the generated power P _G defined in charging reference conditions shrinks enough, the MPPT control more does not occur again mains hunting when resumed, generated power P _G represents a possible increased.

TH _B1 is a zero or a predetermined threshold, smaller than the value of [Delta] P _G (Assuming that is TH _B1 = [Delta] P _G, when the MPPT control resumption, there is a possibility that immediately mains hunting phenomenon occurs For). To perform the setting of the value of TH _B1, the control unit 23 can hold the value of [Delta] P _G. In other words, the predetermined threshold TH _B1 is smaller than the width of the change in the difference between the supplied power and the demand power due to the execution of the hunting suppression control CNT ₂ . By hunting suppression control CNT ₂ is performed, since the generated power P _G is reduced by [Delta] P _G, the width of change in the difference between the power supply and demand electric power becomes [Delta] P _G.

The first release condition is that the state where the absolute value of the difference between the supplied power (charged energy P _B ′) and the demand power (storage power reference P _BREF ) is equal to or less than a predetermined threshold TH _B1 continues for a predetermined time. It may be that. Further, the first release condition may be that a state where the difference between the supplied power and the demand power is positive or negative continues for a predetermined time.

The second cancellation condition is satisfied when the charging power amount P _B ′ satisfying the following inequality (A2) is observed.

That is, the control unit 23 _determines that the difference between the supplied power (charged power amount P _B ′) and the demand power (power storage reference power amount P _BREF ) during the execution of the hunting suppression control CNT ₂ is a release condition (second release condition). When the condition is satisfied, the hunting suppression control CNT ₂ is configured to end. The second release condition is that the value obtained by subtracting the supplied power (charging power amount P _B ′) from the demand power (storage power reference power amount P _BREF ) is equal to or greater than a predetermined threshold value TH _B2 . That is, the absolute value of the difference between the supplied power (charging power amount P _B ′) and the demand power (power storage reference power amount P _BREF ) may be equal to or greater than the predetermined threshold value TH _B2 .

In the example of FIG. 23, the timing t _B1 and t _B2 timing t _B1 and t _B2 'suppression control between CNT ₂ because does not satisfy the inequality (A2)' charging power amount P _B in each timing between 'is continued execution However, since the charging power amount P _B ′ at the timing t _B2 ′ satisfies the inequality (A2), the control unit 23 cancels the execution of the suppression control CNT _{2 at} the timing t _B2 ′ and restarts the MPPT control.

If the power conversion loss is ignored, the left side of the equation (A2) _matches (P _BREF −P _G ) or (P _B ^* −P _G ). That is, establishment of formula (A2) is spread enough difference in power storage for reference power P _BREF and ^(* = charge command amount P _B) and the generated power P _G defined in charging reference conditions, the MPPT control This indicates that the amount of generated power _PG is so small that the system-side hunting phenomenon does not occur again when resuming.

TH _B2 is a large predetermined threshold than [Delta] P _G (Assuming that is TH _B2 = [Delta] P _G, because when the MPPT control resumption, there is a possibility that immediately mains hunting phenomenon occurs). That is, the predetermined threshold TH _B2 is greater than the width of the change in the difference between the power supply and demand power by the execution of the hunting suppression control CNT _2. By hunting suppression control CNT ₂ is performed, since the generated power P _G is reduced by [Delta] P _G, the width of change in the difference between the power supply and demand electric power becomes [Delta] P _G.

The second release condition is that the state where the absolute value of the difference between the supplied power (charged energy P _B ′) and the demand power (storage power reference P _BREF ) is equal to or greater than a predetermined threshold TH _B2 continues for a predetermined time. It may be that.

Next, the third release condition will be described. In order to confirm the success or failure of the third release condition, the control unit 23, based on the current value I _G and the voltage value V _G , or based on the current value I _GINT and the voltage value V _INT during the execution period of the suppression control CNT ₂ , The charge energy P _B ″ is obtained. The charged power amount P _B ″ corresponds to a value obtained by multiplying the virtual power generation amount that would have been obtained if MPPT control was performed by the power conversion efficiencies of the

power conversion units

21G and 21B.

The virtual power generation amount is a value corresponding to the maximum power of the solar cell. Accordingly, the virtual power generation amount corresponds to a predetermined value. Virtual generated power amount, assuming generated power P _G is obtained by adding the [Delta] P _G in (the power conversion efficiency at the suppression control CNT ₂ execution to be 100%, P B _'' is a virtual This is the same as the amount of generated power (P _G + ΔP _G ).

Then, when the state where the absolute value | P _B ″ −P _BREF | is positive is continuously observed for a predetermined time or more, the control unit 23 determines that the third release condition is satisfied. This is because it is expected that the system-side hunting phenomenon will not occur even if the MPPT control is resumed under the situation where the observation is made.

That is, the control unit 23 determines that the difference between the demand power (storage power reference amount P _BREF ) and the predetermined value (virtual power generation amount) satisfies the release condition (third release condition) during the execution of the hunting suppression control CNT _2. The hunting suppression control CNT ₂ is terminated.

The third release condition is that the state where the difference between the demand power (reference power amount P _BREF for power storage) and the predetermined value (virtual power generation amount) is positive or negative continues for a predetermined time (predetermined second time). is there.

The third release condition is that the absolute value of the difference between the demand power (reference power amount P _BREF for power storage) and the predetermined value (virtual power generation amount) is greater than or equal to the threshold value, or the absolute value of the difference is greater than or equal to the threshold value. It may be that the state is continued for a predetermined time (predetermined first time).

Next, the fourth release condition will be described. The control unit 23 executes the system-side hunting detection process HD _1A during the execution period of the suppression control CNT ₂ and determines that the fourth release condition is satisfied when the occurrence of the system-side hunting phenomenon is observed a predetermined number of times or more. To do.

That is, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed during the execution of the hunting suppression control CNT ₂ , and determines that the switching operation has been performed a predetermined number of times. Configured to exit.

The predetermined number of times may be an arbitrary number of 1 or more. This is because when the system-side hunting phenomenon occurs despite the execution of the suppression control CNT ₂ , the system-side hunting phenomenon is avoided due to the increase in the amount of generated power accompanying the restart of the MPPT control.

In the case where quantitative control other than charge quantitative control (discharge quantitative control, system output quantitative control, system input quantitative control) is performed, the above-described release possibility determination process J ₂ is also performed when the suppression control CNT ₂ is executed. Can be executed. However, if the quantitative control of the non-charging quantitative control has been made, the contents of the release determination process J ₂ is modified as follows. First, at the time of execution of system output or system input quantitative control, the above-described timing t _B1 corresponds to the storage side hunting recognition timing.

For discharge quantitative control, the first to third release conditions should be changed as follows.

In the first and second release condition which corresponds to the discharge quantitative control, the above-mentioned formula (A1) and (A2) is changed to respectively the following formulas (B1) and (B2), wherein during the execution of the suppression control CNT ₂ When the amount of power P _G ′ satisfying (B1) or (B2) is observed, the control unit 23 determines that the first or second release condition is satisfied (the first implementation is performed for the definition of P _G ′). See form). Q represents the power consumption of the DC load 8.

That is, the control unit 23 determines the difference between the supplied power (the total value of the generated power amount P _G ′ and the storage reference power amount P _BREF ) and the demand power (power consumption amount Q) during the execution of the hunting suppression control CNT _2. Is configured to end the hunting suppression control CNT ₂ when the release condition (first release condition) is satisfied. The first release condition is that a value obtained by subtracting demand power (power consumption amount Q) from supplied power (total value of generated power amount P _G ′ and power storage reference power amount P _BREF ) is equal to or less than a predetermined threshold TH _B1. (Formula (B1)). In other words, the first cancellation condition is that the absolute value of the difference between the supplied power (the total value of the generated power amount P _G ′ and the storage reference power amount P _BREF ) and the demand power (power consumption amount Q) is a predetermined threshold TH. _B1 or less.

Predetermined threshold value TH _B1 is smaller than the width of change in the supply power and the power demand by the execution of the hunting suppression control CNT _2. That is, by hunting suppression control CNT ₂ is performed, since the generated power P _G is reduced by [Delta] P _G, the width of change in the difference between the power supply and demand electric power becomes [Delta] P _G.

The first release condition is that the absolute value of the difference between the supplied power (the total amount of the generated power amount P _G ′ and the reference power amount P _BREF for power storage) and the demand power (power consumption amount Q) is a predetermined threshold TH. _It may be that the state of _B1 or less continues for a predetermined time. Further, the first release condition may be that a state where the difference between the supplied power and the demand power is positive or negative continues for a predetermined time.

Further, the control unit 23 determines the difference between the supplied power (the total value of the generated power amount P _G ′ and the storage reference power amount P _BREF ) and the demand power (power consumption amount Q) during the execution of the hunting suppression control CNT _2. Is configured to end the hunting suppression control CNT ₂ when the release condition (second release condition) is satisfied. The second release condition is that a value obtained by subtracting demand power (power consumption Q) from supplied power (total value of generated power P _G ′ and power storage reference power P _BREF ) is equal to or greater than a predetermined threshold TH _B2. (Formula (B2)). That is, the second cancellation condition is that the absolute value of the difference between the supplied power (the total value of the generated power amount P _G ′ and the power storage reference power amount P _BREF ) and the demand power (power consumption amount Q) is a predetermined threshold TH. _B2 or higher.

The predetermined threshold value TH _B2 is larger than the width of change in the difference between the supplied power and the demand power due to the execution of the hunting suppression control CNT ₂ . That is, by hunting suppression control CNT ₂ is performed, since the generated power P _G is reduced by [Delta] P _G, the width of change in the difference between the power supply and demand electric power becomes [Delta] P _G.

The second release condition is that the absolute value of the difference between the supplied power (the total amount of the generated power amount P _G ′ and the power storage reference power amount P _BREF ) and the demand power (power consumption amount Q) is a predetermined threshold TH. _The state of _B2 or more may be continued for a predetermined time.

Further, regarding the discharge quantitative control, the control unit 23 determines the electric energy P _G based on the current value I _G and the voltage value V _G or based on the current value I _GINT and the voltage value V _INT during the execution period of the suppression control CNT _2. Ask for ''. The power amount P _G ″ corresponds to the virtual power generation amount multiplied by the power conversion efficiency of the power conversion unit 21 _G (assuming that the power conversion efficiency is 100%, P _G ″ is virtual This is the same as the amount of generated power (P _G + ΔP _G ). Then, when the state where the absolute value | P _G ″ + P _BREF −Q | is positive is continuously observed for a predetermined time or more, the control unit 23 satisfies the third release condition corresponding to the discharge quantitative control. Judge.

That is, during the execution of the hunting suppression control CNT ₂ , the control unit 23 _calculates the total value of the power source power (storage power reference power amount P _BREF ) and the predetermined value (virtual power generation power amount P _G ″) and the power demand (consumption). When the difference from the electric energy Q) satisfies the release condition (third release condition), the hunting suppression control CNT ₂ is configured to end.

The third release condition is that the difference between the total value of the power source power (storage power reference amount P _BREF ) and the predetermined value (virtual power generation amount P _G ″) and the demand power (power consumption amount Q) is positive or That is, the negative state has continued for a predetermined time (predetermined second time).

The third release condition is that the difference between the total value of the power source power (storage power reference power P _BREF ) and the predetermined value (virtual power generation power P _G ″) and the power demand (power consumption Q). It may be that the absolute value is equal to or greater than the threshold value, or that the state where the absolute value of the difference is equal to or greater than the threshold value continues for a predetermined time (predetermined first time).

The fourth release condition corresponding to the discharge quantitative control is the same as the fourth release condition described above for the charge quantitative control. That is, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed during the execution of the hunting suppression control CNT ₂ , and determines that the switching operation has been performed a predetermined number of times. Configured to terminate CNT ₂ .

For grid output quantitative control, the first to third release conditions should be changed as follows.

In the first and second release conditions corresponding to the system output quantitative control, the above formulas (A1) and (A2) are changed to the following formulas (C1) and (C2), respectively, and during the execution period of the suppression control CNT ₂ When the electric energy P _S ′ satisfying the expression (C1) or (C2) is observed, the control unit 23 determines that the first or second release condition is satisfied (for the definition of P _S ′, the first See embodiment).

That is, the control unit 23 determines that the difference between the supplied power (system output power amount P _S ′) and the demand power (system power reference amount P _SREF ) during the execution of the hunting suppression control CNT ₂ is the release condition (first release condition). ), The hunting suppression control CNT ₂ is configured to end. The first release condition is that the value obtained by subtracting the supplied power (system output power P _S ′) from the demand power (system reference power P _SREF ) is equal to or less than a predetermined threshold TH _B1 (formula (C1)) ). That is, the first release condition is that the absolute value of the difference between the supplied power (system output power amount P _S ′) and the demand power (system reference power amount P _SREF ) is equal to or less than a predetermined threshold value TH _B1 .

The first release condition is that a state where the absolute value of the difference between the supplied power (system output power amount P _S ′) and the demand power (system reference power amount P _SREF ) is equal to or less than a predetermined threshold value TH _B1 is a predetermined time. It may be continued. Further, the first release condition may be that a state where the difference between the supplied power and the demand power is positive or negative continues for a predetermined time.

In addition, the control unit 23 determines that the difference between the supply power (system output power amount P _S ′) and the demand power (system power reference amount P _SREF ) is canceled during the execution of the hunting suppression control CNT ₂ (second release condition). ), The hunting suppression control CNT ₂ is configured to end. The second cancellation condition is that the value obtained by subtracting the supplied power (system output power P _S ′) from the demand power (system reference power P _SREF ) is equal to or greater than a predetermined threshold TH _B2 (formula (C2)) ). That is, the second cancellation condition is that the absolute value of the difference between the supplied power (system output power amount P _S ′) and the demand power (system reference power amount P _SREF ) is equal to or greater than a predetermined threshold value TH _B2 .

Note that the second release condition is that a state where the absolute value of the difference between the supplied power (system output power amount P _S ′) and the demand power (system reference power amount P _SREF ) is equal to or greater than a predetermined threshold value TH _B2 is a predetermined time. It may be continued.

Also relates to channel output quantitative control, the control unit 23, during the execution period of the suppression control CNT _2, based on current value I _G and based on the voltage value V _G or a current value I _GINT and the voltage value V _INT, power P _{Find S} ''. The power amount P _S ″ corresponds to the virtual power generation amount multiplied by each power conversion efficiency of the

power conversion units

21G and 21S (assuming that each power conversion efficiency is 100%, P _S ′ 'Is equal to the virtual power generation amount (P _G + ΔP _G )). Then, when the state where the absolute value | P _S ″ −P _SREF | is positive is continuously observed for a predetermined time or longer, the control unit 23 satisfies the third release condition corresponding to the system output quantitative control. Judge.

That is, the control unit 23 determines that the difference between the demand power (system reference power amount P _SREF ) and the predetermined value (virtual power generation power amount P _S ″) during the execution of the hunting suppression control CNT ₂ is the release condition (third release). When the condition (condition) is satisfied, the hunting suppression control CNT ₂ is configured to end.

The third release condition is that a state in which the difference between the demand power (system reference power amount P _SREF ) and the predetermined value (virtual generated power amount P _S ″) is positive or negative is a predetermined time (predetermined second time). It was continued.

The third release condition is that the absolute value of the difference between the demand power (system reference power amount P _SREF ) and the predetermined value (virtual generated power amount P _S ″) is greater than or equal to the threshold value, or the absolute difference The state where the value is equal to or greater than the threshold may be continued for a predetermined time (predetermined first time).

For system input quantitative control, the first to third release conditions should be changed as follows.

In the first and second release conditions corresponding to the system input quantitative control, the above formulas (A1) and (A2) are changed to the following formulas (D1) and (D2), respectively, and during the execution period of the suppression control CNT ₂ When the power amount P _G ′ satisfying the expression (D1) or (D2) is observed, the control unit 23 determines that the first or second release condition is satisfied.

That is, the control unit 23 determines the difference between the supply power (the total value of the generated power amount P _G ′ and the grid reference power amount P _SREF ) and the demand power (power consumption amount Q) during the execution of the hunting suppression control CNT _2. Is configured to end the hunting suppression control CNT ₂ when the release condition (first release condition) is satisfied. The first cancellation condition is that a value obtained by subtracting demand power (power consumption amount Q) from supplied power (total value of generated power amount P _G ′ and grid reference power amount P _SREF ) is equal to or less than a predetermined threshold TH _B1. (Formula (D1)). That is, the first cancellation condition is that the absolute value of the difference between the supplied power (the total amount of the generated power amount P _G ′ and the grid reference power amount P _SREF ) and the demand power (power consumption amount Q) is a predetermined threshold TH. _B1 or less.

The first release condition is that the absolute value of the difference between the supplied power (the total amount of the generated power amount P _G ′ and the grid reference power amount P _SREF ) and the demand power (power consumption amount Q) is a predetermined threshold TH. _It may be that the state of _B1 or less continues for a predetermined time. Further, the first release condition may be that a state where the difference between the supplied power and the demand power is positive or negative continues for a predetermined time.

In addition, the control unit 23 determines the difference between the supply power (the total value of the generated power amount P _G ′ and the grid reference power amount P _SREF ) and the demand power (power consumption amount Q) during the execution of the hunting suppression control CNT _2. Is configured to end the hunting suppression control CNT ₂ when the release condition (second release condition) is satisfied. The second cancellation condition is that a value obtained by subtracting demand power (power consumption Q) from supplied power (total value of generated power P _G ′ and grid reference power P _SREF ) is equal to or greater than a predetermined threshold value TH _B2 (Formula (D2)). That is, the second cancellation condition is that the absolute value of the difference between the supplied power (the total amount of the generated power amount P _G ′ and the grid reference power amount P _SREF ) and the demand power (power consumption amount Q) is a predetermined threshold TH. _B2 or higher.

The second release condition is that the absolute value of the difference between the supplied power (the total amount of the generated power amount P _G ′ and the grid reference power amount P _SREF ) and the demand power (power consumption amount Q) is a predetermined threshold TH. _The state of _B2 or more may be continued for a predetermined time.

Further, regarding the system input quantitative control, the control unit 23 performs the above-described power based on the current value I _G and the voltage value V _G or based on the current value I _GINT and the voltage value V _INT during the execution period of the suppression control CNT _2. Determine the quantity P _G ″. Then, the control unit 23 satisfies the third release condition corresponding to the system input quantitative control when a state where the absolute value | P _G ″ + P _SREF −Q | is positive is continuously observed for a predetermined time or more. Judge that

That is, during execution of the hunting suppression control CNT ₂ , the control unit 23 _calculates the total value of the power source power (system reference power amount P _SREF ) and the predetermined value (virtual power generation power amount P _G ″) and the demand power (consumption). When the difference from the electric energy Q) satisfies the release condition (third release condition), the hunting suppression control CNT ₂ is configured to end.

The third release condition is that the difference between the total value of the power source power (system reference power amount P _SREF ) and the predetermined value (virtual power generation amount P _G ″) and the demand power (power consumption amount Q) is positive or That is, the negative state has continued for a predetermined time (predetermined second time).

The third release condition is that the difference between the total value of the power source power (system reference power amount P _SREF ) and the predetermined value (virtual power generation amount P _G ″) and the demand power (power consumption amount Q). It may be that the absolute value is equal to or greater than the threshold value, or that the state where the absolute value of the difference is equal to or greater than the threshold value continues for a predetermined time (predetermined first time).

When the suppression control CNT ₂ is executed when the system output quantitative control or the system input quantitative control is executed, the control unit 23 executes the storage side hunting detection process HD _1C and observes the occurrence of the storage side hunting phenomenon for a predetermined number of times or more. It is good to determine that the fourth release condition has been satisfied. The predetermined number of times may be an arbitrary number of 1 or more.

That is, the 4th cancellation conditions corresponding to system output fixed control and system input fixed control are the same as the 4th cancellation conditions mentioned above about charge fixed control. That is, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed during the execution of the hunting suppression control CNT ₂ , and determines that the switching operation has been performed a predetermined number of times. Configured to terminate CNT ₂ .

3. Operation Flowchart Next, an operation flow of the power conversion device 2 will be described with reference to FIG. FIG. 24 is an operation flowchart of the power conversion apparatus 2 focusing on the above-described various quantitative controls. Steps S22 and S23 are the same as steps S12 and S13 in FIG.

First, in step S21, the control unit 23 starts executing any quantitative control and also starts executing MPPT control.

Thereafter, in step S22, the control unit 23 performs the above-described hunting detection process or prediction process based on the input / output power information.

In subsequent step S23, the control unit 23 checks whether the hunting detection determination or the prediction determination is made, and if any of the determinations is made, the control unit 23 shifts to step S24 to execute the hunting suppression control CNT ₂ . Execution is started (ie, MPPT control is stopped).

After the execution of the hunting suppression control CNT ₂ is started, the control unit 23 performs a release permission determination process J ₂ for the hunting suppression control CNT ₂ (step S25).

Control unit 23, until one of the first to fourth release condition is satisfied to continue execution of the hunting suppression control CNT ₂ (steps S25 and S26), when it is confirmed fulfillment of releasing condition hunting suppression control CNT ₂ Is canceled (step S27), and the process returns to step S22.

As described above, MPPT control is resumed by the release of the execution of the hunting suppression control CNT _2.

4). Characteristics of Power Converter 2 of the Present Embodiment The power converter 2 of the present embodiment described above has the following first characteristics. In the first feature, the power conversion device 2 includes a power conversion circuit 20 and a control unit 23. The power conversion circuit 20 includes a power storage side circuit (power conversion unit 21B) connected to the power storage device 3 that can be charged and discharged, and a power generation side circuit (power) connected to the power generation device 4 that generates power and outputs generated power. It has a system side circuit (power conversion unit 21S) connected to the conversion unit 21G) and the power system 5. The power conversion circuit 20 is configured to perform power transmission and reception between the power storage device 3, the power generation device 4, and the power system 5 through power conversion. The control unit 23 is configured to control power transmission and power reception by controlling the power conversion circuit 20. The control unit 23 absorbs the shortage or surplus of the generated power at the input / output of the power between the power conversion circuit 20 and the power system 5 and uses the generated power of the power generation device 4 to keep the power storage device 3 at a certain level. A power storage device that is charged under one reference condition or that supplies power to at least one of a load and a secondary battery connected to the power conversion circuit 20 using the generated power of the power generation device 4 and the discharge power of the power storage device 3 Quantitative control for discharging 3 under a constant second reference condition is executed. In the quantitative control, when switching of power input / output between the power conversion circuit 20 and the power system 5 is detected a predetermined number of times within a predetermined time, or a value corresponding to the generated power amount or the generated power amount of the power generation device 4 When the occurrence of switching is predicted based on the first reference condition or the second reference condition, the control unit 23 changes the power generation amount of the power generation device 4 through the change of the power point of the power generation device 4. The suppression control that suppresses the switching is executed.

The power conversion device 2 of the present embodiment has the following second feature. In the following second feature, the power conversion device 2, the power conversion device 2, the power conversion circuit 20, the control unit 23, Is provided. The power conversion circuit 20 includes a power storage side circuit (power conversion unit 21B) connected to the power storage device 3 that can be charged and discharged, and a power generation side circuit (power) connected to the power generation device 4 that generates power and outputs generated power. It has a system side circuit (power conversion unit 21S) connected to the conversion unit 21G) and the power system 5. The power conversion circuit 20 is configured to perform power transmission and reception between the power storage device 3, the power generation device 4, and the power system 5 through power conversion. The control unit 23 is configured to control power transmission and power reception by controlling the power conversion circuit 20. The control unit 23 absorbs the shortage or surplus of the generated power by charging or discharging the power storage device 3, and uses the generated power of the power generation device 4 to transfer the constant first power from the power conversion circuit 20 to the power system 5. Output power under reference conditions, or supply power to at least one of a load and a secondary battery connected to the power conversion circuit 20 using generated power and input power from the power system 5 to the power conversion circuit 20 Quantitative control for inputting power from the power system 5 to the power conversion circuit 20 under a constant second reference condition is performed. In the quantitative control, when switching of power input / output between the power conversion circuit 20 and the power storage device 3 is detected a predetermined number of times or more within a predetermined time, the generated power amount of the power generation device 4 or a value corresponding to the generated power amount When occurrence of switching is predicted based on the first reference condition or the second reference condition, the control unit 23 performs switching by changing the power generation amount of the power generation device 4 through a change in the power point of the power generation device 4. The suppression control which suppresses is performed.

The power conversion device 2 of the present embodiment has the following third feature in addition to the first or second feature. In the third feature, the control unit 23 generates a power generation circuit (power conversion unit) to operate the power generation device 4 at the first power point that maximizes the amount of power generated by the power generation device 4 before detection or prediction is performed. 21G), and after detection or prediction is performed, the power generation side circuit (power conversion unit 21G) is controlled such that the power point of the power generation device 4 is changed to a second power point different from the first power point. In this way, suppression control is realized.

The power conversion device 2 of the present embodiment has the following fourth feature in addition to any one of the first to third features. In the fourth feature, the control unit 23 determines the predetermined amount based on the value of the generated power amount or the generated power amount of the power generation device 4 and the first reference condition or the second reference condition during the execution period of the suppression control. When it is determined that the release condition is satisfied, the execution of the suppression control is released.

The power conversion device 2 of the present embodiment has the following fifth feature in addition to any one of the first to third features. In the fifth feature, the control unit 23 cancels the execution of the suppression control when switching is detected during the execution period of the suppression control.

In addition, the power converter device 2 should just have at least 1 of a 1st characteristic and a 2nd characteristic. The third to fifth features are arbitrary features.

As described above, the hunting suppression control CNT ₂ according to the second embodiment also has an adverse effect on the system-side hunting phenomenon or the power storage device 3 that affects the stability of the power system 5 as in the first embodiment. It is possible to appropriately suppress the storage-side hunting phenomenon that may be applied. Therefore, according to the present embodiment, it is possible to provide the power conversion device 2 that contributes to suppression of the hunting phenomenon.

In addition, since the hunting suppression control CNT ₂ in the second embodiment does not affect the quantitative control, the desired quantitative control can be continued during the execution period of the hunting suppression control CNT ₂ . However, the hunting suppression control CNT ₂ of the second embodiment is accompanied by a decrease in the amount of generated power. In this regard, whether or not the release condition is satisfied is monitored when the hunting suppression control CNT ₂ is executed, and the hunting suppression control CNT ₂ is released when it is determined that the hunting phenomenon does not occur or hardly occurs even when the execution is canceled. By adopting the method, it is possible to extract as much generated power as possible from the power generator 4 while avoiding the hunting phenomenon as much as possible.

Note that, when the hunting detection process is used without using the hunting prediction process, the hunting suppression control is executed after the occurrence of the hunting phenomenon is detected, so that some hunting phenomenon is allowed to occur. On the other hand, if the hunting prediction process is used, the occurrence of the hunting phenomenon can be completely or almost completely avoided. However, when the hunting prediction process is used, the time for performing the MPPT control is shorter than when the hunting detection process is used. What is necessary is just to set which of a hunting detection process and a prediction process is performed according to which priority is given to hunting phenomenon suppression or generated electric power amount.

Further, the control unit 23 may supply the power conversion unit 21G with a voltage command value V _G ^* that specifies the voltage value V _G instead of the current command value I _G ^* . In this case, the control unit 23 can realize the MPPT control by giving the voltage command value V _G ^* corresponding to the power point 401 to the power conversion unit 21G, and when performing the suppression control CNT ₂ , the power point 402 Alternatively, the voltage command value V _G ^* corresponding to 403 may be given to the power conversion unit 21G.

(Third embodiment)
1. Configuration of Power Converter 2 of Third Embodiment A power converter 2 of this embodiment is related to the power converters 2 of the first, eleventh to eighteenth and twenty-third to twenty-eighth aspects of the present invention.

Hereinafter, a third embodiment of the present invention will be described. The power supply system 1 according to the third embodiment is provided with two power storage devices 3, and correspondingly, the power conversion circuit 20 according to the third embodiment includes a power conversion unit 21B for the power storage device. Are provided. The characteristics, configuration and operation of the power storage device can be made different between the two power storage devices 3, and the characteristics, configuration and operation of the power conversion unit can be made different between the two power conversion units 21B. However, here, for simplification of explanation, each of the two power storage devices 3 has the same characteristics and configuration as the power storage device 3 described in the first embodiment and is the same as the power storage device 3 described in the first embodiment. Operation is realized, and each of the two power conversion units 21B has the same characteristics and configuration as the power conversion unit 21B described in the first embodiment and the same operation as the power conversion unit 21B described in the first embodiment Shall be realized. The control unit 23 can control the power conversion unit 21B described in the first embodiment for each of the two power conversion units 21B.

The power supply system according to the third embodiment including two power storage devices 3 is referred to by reference numeral 1a, the power conversion circuit according to the third embodiment including two power conversion units 21B is referred to by reference numeral 20a, The power conversion device according to the third embodiment including the conversion circuit 20a is referred to by reference numeral 2a.

FIG. 25 is a schematic overall configuration diagram of a power supply system 1a according to the third embodiment. Hereinafter, the two power storage devices 3 are referred to as

power storage devices

3 and 3a, and the two power conversion units 21B are referred to as power conversion units 21B and 21Ba.

1 is added to the power conversion circuit 20 and the power conversion device 2 in FIG. 1 to form the power conversion circuit 20a and the power conversion device 2a in FIG. The power conversion unit 21Ba is provided in the power conversion circuit 20a.

In the power supply system 1 of FIG. 1, the power supply system 1a is formed by replacing the power conversion device 2 with the power conversion device 2a and adding the power storage device 3a. When the description of the first or second embodiment is applied to the third embodiment, the reference numerals “1”, “2”, and “20” in the description of the first or second embodiment are “1a”, It is read as “2a” and “20a”.

The power supply device 2 (2a) of the present embodiment includes a power conversion circuit 20 (20a) and a control unit 23.

The power conversion circuit 20a includes a power receiving function for receiving power from the power supply device, a power transmission function for supplying power to the power demand device, an output process for supplying power to the power auxiliary device, and an input process for acquiring power from the power auxiliary device. And adjusting at least one of an input / output selection function for selectively executing and supply power that is power received from the power supply device and demand power that is power supplied to the power demanding device in accordance with an instruction from the control unit 23 An adjustment function.

Control unit 23 determines whether an event has occurred that hunting occurs in the power conversion circuit 20, configured to perform hunting suppression control CNT ₃ determines that the event has occurred. In the hunting suppression control CNT ₃ , the control unit 23 is configured to give an instruction to the power conversion circuit 20 so that the difference between the supplied power and the demand power becomes large.

In the present embodiment, the power conversion circuit 20a has a second input / output selection function for selectively executing the second output process and the second input process. In the second output process, the power conversion circuit 20a is configured to increase power demand by supplying power to the second power auxiliary device and using the second power auxiliary device as part of the power demand device. In the second input process, the power conversion circuit 20a is configured to acquire power from the second power auxiliary device and increase the supply power by using the second power auxiliary device as a part of the power supply device.

The second power auxiliary device is the second power storage device 3a. The power conversion circuit 20a is configured to charge the second power storage device 3a in the second output process and to discharge the second power storage device 3a in the second input process.

In the present embodiment, the hunting suppression control CNT ₃ includes a first hunting suppression control CNT _3A that causes the power conversion circuit 20a to execute a second output process, and a second hunting suppression control that causes the power conversion circuit 20a to execute a second input process. CNT _3B .

When the control unit 23 determines that an event has occurred, the control unit 23 executes one of the first hunting suppression control CNT _3A and the second hunting suppression control CNT _3B so that the difference between the supplied power and the demand power becomes large. Composed.

For example, when it is determined that an event has occurred, the control unit 23 is configured to compare the remaining amount of power of the second power storage device 3a with a predetermined value. The controller 23 is configured to execute the first hunting suppression control CNT _3A if the remaining amount is less than the predetermined value, and to execute the second hunting suppression control CNT _3B if the remaining amount is equal to or greater than the predetermined value.

Power conversion unit (fourth power conversion unit) 21Ba corresponds to the power terminal T _B1 and power terminal T _B2 of the power conversion unit 21B, the power terminals (external power terminal) T _B1a and power terminals (internal power terminal) T _B2a Have That is, the power conversion unit 21Ba has a (fourth) external power terminal T _B1a and (4) the internal power terminal T _B2a, is connected to the second power storage device 3a.

Power storage device 3a is connected to the power conversion unit 21Ba by the power terminal T _B1a, it is possible to output its discharge power to the power conversion unit 21Ba, charging when the power conversion unit 21Ba supplied with the charging power Is done.

The power terminals (internal power terminals) T _B2a , T _B2 , T _G2, and T _S2 are commonly connected in the power conversion circuit 20 a by the intermediate wiring 22.

The power conversion circuit 20a performs power transmission and power reception among the power storage device 3, the power storage device 3a, the power generation device 4, and the power system 5 under the control of the control unit 23, and performs necessary power conversion at the time of power transmission and power reception. .

The power conversion unit 21Ba converts the DC discharge power received from the power storage device 3a through the power terminal T _B1a into another DC power and outputs the other DC power from the power terminal T _B2a. , Converting the DC power received via the power terminal T _B2a into another DC power and performing the power conversion for charging to output the other DC power to the power storage device 3a as the charging power via the power terminal T _B1a Is possible.

That is, the power conversion unit 21Ba has a second input / output selection function that selectively executes the second output process (second charge power conversion) and the second input process (second discharge power conversion).

Further, the power conversion unit 21Ba, in response to an instruction from the control unit 23, supplies power (discharge power) that is power received from the second power storage device 3a as the second power auxiliary device and the second power auxiliary device as the second power auxiliary device. 2 It has a function of adjusting demand power (charging power) that is power supplied to the power storage device 3a.

That is, the power conversion unit 21Ba responds to an instruction from the control unit 23 and supplies power (discharge power) that is the amount of power received from the second power storage device 3a and the amount of power supplied to the second power storage device 3a. The amount of demand power (charging power amount) is adjusted.

Therefore, when receiving the target value of the discharge power (discharge power amount) from the control unit 23, the power conversion unit 21Ba adjusts the discharge power (discharge power amount) to the target value. Further, when receiving the target value of the charging power (charging power amount) from the control unit 23, the power conversion unit 21Ba adjusts the charging power (charging power amount) to the target value.

The operation of the

power converters

21B, 21G, and 21S is as described in the first embodiment. However, with the addition of the power storage device 3a and the power conversion unit 21Ba, the power from the power storage device 3, the power generation device 4, or the power system 5 may be sent to the power storage device 3a, and the power from the power storage device 3a is stored in the power storage device. 3. It may be sent to the electric power system 5 or the DC load 8.

In the third embodiment, the input / output power information acquired by the control unit 23 includes the current value I _Ba and the voltage value based on the measurement results of the current sensor and the voltage sensor in addition to the values described in the first embodiment. It includes V _Ba and the current value I _BINTa, and may include electric power amounts P _Ba and P _BINTa represented by the following formulas (1g) and (1h).

For example, the power converter 2a includes a plurality of current sensors (not shown) that measure values I _B , I _Ba , I _G , and I _S of currents flowing through the external power terminals T _B1 , T _B1a , T _G1 , and T _S1. ) And a plurality of current sensors (not shown) for measuring the values I _BINT , I _BINTa , I _GINT , and I _SINT of the currents flowing through the internal power terminals T _B2 , T _B2a , T _G2 , and T _S2 , respectively. .

Further, the power converter 2a includes a plurality of voltage sensors (not shown) that measure the voltage values V _B , V _Ba , V _G , and V _S of the external power terminals T _B1 , T _B1a , T _G1 , and T _S1. ) And a voltage sensor (not shown) for measuring the value V _INT of the voltages of the internal power terminals T _B2 , T _B2a , T _G2 , T _S2 (that is, the voltage of the intermediate wiring 22).

I _Ba , V _Ba, and P _Ba are output from the power storage unit 3a to the power conversion unit 21Ba, respectively, as a current value, a voltage value, and a power amount in the discharge power of the power storage device 3a, or output from the power conversion unit 21Ba to the power storage device 3a. Current value, voltage value, and electric energy in the charging power of the power storage device 3a. I _BINTa and V _INT are current values and voltage values corresponding to I _Ba and V _Ba before or after power conversion in the power converter 21Ba.

Based on the input / output power information, the control unit 23 controls the operation of the power conversion circuit 20a including the operations of the power conversion units 21B, 21Ba, 21G, and 21S, and controls the operation of the power conversion circuit 20a. The power transmission device 3, the power storage device 3 a, the power generation device 4, and the power grid 5 are controlled.

Also in the third embodiment, the control unit 23 can individually execute the charge quantitative control, the discharge quantitative control, the system output quantitative control, and the system input quantitative control described in the first embodiment.

In charge quantitative control, the power generation device 4 is used as a power supply device, the power storage device 3 is used as a power demand device, and the power system 5 is used as a power auxiliary device. The second power storage device 3a is used as a power supply device or a power demand device. The supplied power is the sum of the generated power from the power generator 4 and the discharged power from the second power storage device 3a. The demand power is the sum of the charging power for the power storage device 3 and the charging power for the second power storage device 3a.

In the discharge quantitative control, the power generation device 4 and the power supply device (power storage device 3) are used as a power supply device, the DC load 8 is used as a power demand device, and the power system 5 is used as a power auxiliary device. The second power storage device 3a is used as a power supply device or a power demand device. Accordingly, the supplied power is the sum of the generated power from the power generation device 4, the power source power (discharge power of the power storage device 3) that is power obtained from the power supply device, and the discharge power from the second power storage device 3a. The demand power is the sum of the power consumption of the DC load 8 and the charging power for the second power storage device 3a.

In the grid output quantitative control, the power generation device 4 is used as a power supply device, the power system 5 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device. The second power storage device 3a is used as a power supply device or a power demand device. The supplied power is the total value of the generated power from the power generator 4 and the discharged power from the second power storage device 3a. The demand power is the total value of the output power to the power system 5 and the charging power to the second power storage device 3a.

In the grid input quantitative control, the power generation device 4 and the power supply device (power system 5) are used as a power supply device, the DC load 8 is used as a power demand device, and the power storage device 3 is used as a power auxiliary device. The second power storage device 3a is used as a power supply device or a power demand device. Therefore, the supplied power is the sum of the generated power from the power generation device 4, the power source power (input power of the power system 5) that is power obtained from the power source device, and the discharge power from the second power storage device 3a. The demand power is the sum of the power consumption of the DC load 8 and the charging power for the second power storage device 3a.

When each quantitative control is performed, the charging or discharging state of the power storage device 3a is not limited, but here, for the sake of concrete description, the charging of the power storage device 3a is performed during a period in which hunting suppression control CNT ₃ described later is not performed. And the discharge power is zero. Further, as described in the description of the second embodiment, the control unit 23 performs the hunting detection process (HD _1A , HD _1B , HD _1C) corresponding to the quantitative control being executed during the execution period of each quantitative control. , HD _1D ) or hunting prediction processing (HP _1A , HP _1B , HP _1C , HP _1D ) can be executed.

2. Details of control 2.1 Hunting suppression control CNT ₃
When system-side hunting detection judgment or system-side hunting prediction judgment is made during the period when charge quantitative control or discharge quantitative control is executed, or during the period when system output quantitative control or system input quantitative control is executed when it made a power storage side hunting detection determination or power storage side hunting prediction judgment, the control unit 23 performs the hunting suppression control CNT ₃ in which power is input and output between the power conversion circuit 20a and the power storage device 3a. The power input / output between the power conversion circuit 20a and the power storage device 3a means power output from the power conversion circuit 20a to the power storage device 3a or power input from the power storage device 3a to the power conversion circuit 20a. The power output from the power conversion circuit 20a to the power storage device 3a means that charging power is supplied from the power conversion unit 21Ba to the power storage device 3a. The power input from the power storage device 3a to the power conversion circuit 20a is the power storage device 3a. Is supplied to the power converter 21Ba.

In the hunting suppression control CNT ₃ applied to the charge quantitative control or the discharge quantitative control, the absolute value of the input / output power amount between the power conversion circuit 20 and the power system 5 by the power input / output between the power conversion circuit 20a and the power storage device 3a. Thereby suppressing the system-side hunting phenomenon.

In the hunting suppression control CNT ₃ applied to the system output quantitative control or the system input quantitative control, the input / output power amount between the power conversion circuit 20 and the power storage device 3 is determined by the power input / output between the power conversion circuit 20a and the power storage device 3a. The absolute value is increased, thereby suppressing the power storage side hunting phenomenon. The suppression control CNT ₃ is control performed in each quantitative control, and the execution of the suppression control CNT ₃ does not affect the contents of each quantitative control.

As described above, when the control unit 23 determines that the event has occurred, the control unit 23 performs either one of the first hunting suppression control CNT _3A and the second hunting suppression control CNT _3B so that the difference between the supplied power and the demand power becomes large. Configured to run.

In the first hunting suppression control, the control unit 23 causes the power conversion circuit 20a to execute the second output process. As a result, the second power storage device 3a is discharged. Considering the demand power as a reference, the power supply (power supply amount) has increased. Conversely, if the supplied power is considered as a reference, the demand power (demand power amount) has decreased.

In the second hunting suppression control, the control unit 23 causes the power conversion circuit 20a to execute the second input process. Thereby, the second power storage device 3a is charged. Considering supply power as a reference, demand power (demand power amount) has increased. Conversely, if the demand power is considered as a reference, the supply power (supply power amount) has decreased.

FIGS. 26A and 26B are conceptual diagrams of the suppression control CNT ₃ that can be performed during the execution period of the charge quantitative control. FIGS. 27A and 27B are conceptual diagrams of the suppression control CNT ₃ that can be performed during the execution of the discharge quantitative control.

When the system-side hunting phenomenon as in the example of FIG. 3C or FIG. 10C is detected or predicted, the control unit 23 performs the suppression control CNT ₃ in FIG. 26A or FIG. As shown in FIG. 26, the power conversion unit 21Ba is controlled so that a predetermined amount of charging power is supplied from the power conversion unit 21Ba to the power storage device 3a, or as shown in FIG. 26B or FIG. The power conversion unit 21Ba is controlled so that a predetermined amount of discharge power is output from the power storage device 3a to the power conversion unit 21Ba.

In the examples of FIG. 26A and FIG. 27A, it can be considered that all or part of the charging power of the power storage device 3a is supplied from the power system 5, or the power generation device 4 or the power storage device 3 It can be thought that it is supplied from.

In the case of charge constant control, the amount of supplied power (the sum of the generated power from the power generation device 4 and the discharge power from the second power storage device 3a) and the amount of demand power (the charge power to the power storage device 3 and the second power storage device 3a). And the total charge power).

For example, the power generation amount of the power generation device 4 is 10 kW · s, and the charge power amount of the power storage device 3 is 10 kW · s. In this case, if the control unit 23 executes the first hunting suppression control CNT _3A and sets the discharge power (discharge power amount) from the second power storage device 3a to 2 kW · s, the supply power amount increases by 2 kW · s and increases to 12 kW. S (of course, the charging power of the second power storage device 3a is 0 kW · s). Since the amount of power demand is 10 kW · s, the supplied power is more than 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the output power to the power conversion unit 21S, and thereby supplies the output power of 2 kW · s to the power system 5 (see FIG. 26B).

On the other hand, when the control unit 23 executes the second hunting suppression control CNT _3B and sets the charging power (charging power amount) from the second power storage device 3a to 2 kW · s, the demand power amount increases by 2 kW · s and increases to 12 kW · s. (Of course, the discharge power of the second power storage device 3a is 0 kW · s). Since the power supply amount is 10 kW · s, the power supply is insufficient by 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the input power to the power conversion unit 21S, and thereby obtains input power of 2 kW · s from the power system 5 (see FIG. 26A).

In the examples of FIGS. 26B and 27B, it can be considered that all or part of the discharged power of the power storage device 3a is output to the power system 5, or the power storage device 3 or the DC load 8 You can also think that it is output to.

In the case of the discharge quantitative control, the amount of supplied power (the sum of the generated power from the power generation device 4, the discharge power from the power storage device 3, and the discharge power from the second power storage device 3a) and the demand power (of the DC load 8). The sum of the power consumption and the charging power for the second power storage device 3a) is compared.

For example, the generated power amount of the power generation device 4 is 10 kW · s, the discharged power amount of the power storage device 3 is 10 kW · s, and the consumed power amount of the DC load 8 is 20 kW · S. In this case, if the control unit 23 executes the first hunting suppression control CNT _3A and sets the discharge power (discharge power amount) from the second power storage device 3a to 2 kW · s, the supply power amount increases by 2 kW · s and increases to 22 kW. S (of course, the charging power of the second power storage device 3a is 0 kW · s). Since the amount of power demand is 20 kW · s, the supplied power is more than 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the output power to the power conversion unit 21S, thereby supplying the output power of 2 kW · s to the power system 5 (see FIG. 27B).

On the other hand, when the control unit 23 executes the second hunting suppression control CNT _3B and sets the charging power (charging power amount) from the second power storage device 3a to 2 kW · s, the demand power amount increases by 2 kW · s and increases to 22 kW · s. (Of course, the discharge power of the second power storage device 3a is 0 kW · s). Since the power supply amount is 20 kW · s, the power supply is insufficient by 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the input power to the power conversion unit 21S, and thereby obtains input power of 2 kW · s from the power system 5 (see FIG. 27A).

In any case, the charging or discharging of the power storage device 3a causes a continuous flow of power in a certain direction between the power conversion circuit 20a and the power system 5, thereby suppressing the system-side hunting phenomenon.

FIGS. 28A and 28B are conceptual diagrams of the suppression control CNT ₃ that can be performed during the execution period of the system output quantitative control. FIGS. 29A and 29B are conceptual diagrams of the suppression control CNT ₃ that can be performed during the execution period of the system input quantitative control.

When the storage-side hunting phenomenon as in the example of FIG. 13 (c) or FIG. 16 (c) is detected or predicted, the control unit 23 performs the suppression control CNT ₃ in FIG. 28 (a) or FIG. 29 (a). As shown in FIG. 28, the power conversion unit 21Ba is controlled so that a predetermined amount of charging power is supplied from the power conversion unit 21Ba to the power storage device 3a, or as shown in FIG. 28 (b) or FIG. 29 (b), The power conversion unit 21Ba is controlled so that a predetermined amount of discharge power is output from the power storage device 3a to the power conversion unit 21Ba.

In the example of FIG. 28A and FIG. 29A, it can be considered that all or part of the charging power of the power storage device 3a is supplied from the power storage device 3, or the power generation device 4 or the power system 5 It can be thought that it is supplied from.

In the case of grid output quantitative control, the amount of supplied power (the sum of the generated power from the power generation device 4 and the discharge power from the second power storage device 3a) and the demand power (the output power to the power system 5 and the second power storage device 3a). And the total charging power).

For example, the power generation amount of the power generation device 4 is 10 kW · s, and the output power amount of the power system 5 is 10 kW · s. In this case, if the control unit 23 executes the first hunting suppression control CNT _3A and sets the discharge power (discharge power amount) from the second power storage device 3a to 2 kW · s, the supply power amount increases by 2 kW · s and increases to 12 kW. S (of course, the charging power of the second power storage device 3a is 0 kW · s). Since the amount of power demand is 10 kW · s, the supplied power is more than 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the charging power to the power conversion unit 21B, and thereby supplies the charging power of 2 kW · s to the power storage device 3 (see FIG. 28B).

On the other hand, when the control unit 23 executes the second hunting suppression control CNT _3B and sets the charging power (charging power amount) from the second power storage device 3a to 2 kW · s, the demand power amount increases by 2 kW · s and increases to 12 kW · s. (Of course, the discharge power of the second power storage device 3a is 0 kW · s). Since the power supply amount is 10 kW · s, the power supply is insufficient by 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the discharge power to the power conversion unit 21B, thereby obtaining 2 kW · s of discharge power from the power storage device 3 (see FIG. 28A).

In the example of FIG. 28B and FIG. 29B, it can be considered that all or part of the discharged power of the power storage device 3a is output to the power storage device 3, or the power system 5 or the DC load 8 You can also think that it is output to.

In the case of grid input quantitative control, the amount of supplied power (the sum of the generated power from the power generation device 4, the input power from the power system 5, and the discharge power from the second power storage device 3a) and the demand power (DC load 8). Power consumption and the sum of the charging power for the second power storage device 3a).

For example, the power generation amount of the power generation device 4 is 10 kW · s, the input power amount of the power system 5 is 10 kW · s, and the power consumption of the DC load 8 is 20 kW · S. In this case, if the control unit 23 executes the first hunting suppression control CNT _3A and sets the discharge power (discharge power amount) from the second power storage device 3a to 2 kW · s, the supply power amount increases by 2 kW · s and increases to 22 kW. S (of course, the charging power of the second power storage device 3a is 0 kW · s). Since the amount of power demand is 20 kW · s, the supplied power is more than 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the charging power to the power conversion unit 21B, and thereby supplies 2 kW · s of charging power to the power storage device 3 (see FIG. 29B).

On the other hand, when the control unit 23 executes the second hunting suppression control CNT _3B and sets the charging power (charging power amount) from the second power storage device 3a to 2 kW · s, the demand power amount increases by 2 kW · s and increases to 22 kW · s. (Of course, the discharge power of the second power storage device 3a is 0 kW · s). Since the power supply amount is 20 kW · s, the power supply is insufficient by 2 kW · s. In this way, the difference between the supplied power amount and the demand power amount becomes large, and the hunting phenomenon is suppressed. In this case, the control unit 23 gives 2 kW · s as the target value of the discharge power to the power conversion unit 21B, thereby obtaining 2 kW · s of discharge power from the power storage device 3 (see FIG. 29A).

In any case, the charging or discharging of the power storage device 3a causes a continuous flow of power between the power conversion circuit 20a and the power storage device 3 and suppresses the power storage-side hunting phenomenon.

2.2 Release possibility determination process The release possibility determination process that can be performed during the execution period of the hunting suppression control CNT ₃ is the same as that described in the first embodiment. That is, when the suppression control CNT ₃ is executed when the charge quantitative control, the discharge quantitative control, the system output quantitative control, or the system input quantitative control is performed, during the execution period of the suppression control CNT ₃ , the control unit 23 Each of the above-described release permission / inhibition determination processes J _1A , J _1B , J _1C, or J _1D can be performed. When applying the descriptive text of the first embodiment about the release possibility determination process J _1A , J _1B , J _1C or J _1D to the third embodiment, the symbols “CNT _1A ”, “CNT _1B ”, “CNT _1C ” and “CNT _1D ” should all be read as “CNT ₃ ”.

For example, the power conversion circuit 2 (2a) is configured to increase the demand power from the first predetermined value in the second output process. Control unit 23, the configuration in the case where the difference between the power supply and the first predetermined value during execution of the first hunting suppression control CNT _3A satisfies a first release condition, so as to end the first hunting suppression control CNT _3A Is done. The first release condition is that the first absolute value of the difference between the supplied power and the first predetermined value is equal to or greater than the first threshold, and the state where the first absolute value is equal to or greater than the first threshold continues for a predetermined first time. Or a state in which the difference between the supplied power and the first predetermined value is positive or negative has continued for a predetermined second time.

Further, the power conversion circuit 2 (2a) is configured to increase the supply power from the second predetermined value in the second input process. The control unit 23 is configured to end the second hunting suppression control CNT _3B when the difference between the demand power and the second predetermined value satisfies the second release condition during the execution of the second hunting suppression control. . The second release condition is that the second absolute value of the difference between the demand power and the second predetermined value is equal to or greater than the second threshold, and the state where the second absolute value is equal to or greater than the second threshold continues for a predetermined third time. Or a state in which the difference between the demand power and the second predetermined value is positive or negative has continued for a predetermined fourth time.

Or the control unit 23, when the difference between the power supply and demand electric power during the hunting prevention control CNT ₃ satisfies the release condition, configured to terminate the hunting suppression control CNT _3. The cancellation condition is that the absolute value of the difference between the supplied power and the demand power is less than or equal to a predetermined threshold, or that the absolute value of the difference between the supplied power and the demand power is less than or equal to a predetermined threshold has continued for a predetermined time. That is. The predetermined threshold is smaller than the range of change in the difference between the supplied power and the demand power due to the execution of the hunting suppression control. Alternatively, the cancellation condition is that the state where the difference between the supplied power and the demand power is positive or negative continues for a predetermined time.

Note that, as described above, the demand power and the supplied power differ for each of the charge quantitative control, the discharge quantitative control, the system output quantitative control, and the system input quantitative control.

When the release condition in the determination process J _1A is satisfied during the execution of the charge quantitative control and suppression control CNT ₃ , and when the release condition in the determination process J _1B is satisfied during the execution of the discharge quantitative control and suppression control CNT ₃ , When the release condition in the determination process J _1C is satisfied during the execution of the system output quantitative control and the suppression control CNT ₃ , or the release condition in the determination process J _1D is satisfied during the execution of the system input quantitative control and the suppression control CNT ₃ When this is done, the control unit 23 cancels the execution of the suppression control CNT ₃ , that is, stops the power input / output between the power conversion circuit 20 a and the power storage device 3 a (as a result, the charging power and the discharging power of the power storage device 3 a are zero. Back to).

As described in the first embodiment, the control unit 23 executes the system-side hunting detection process HD _1A during the charge quantitative control or the discharge quantitative control and the suppression control CNT ₃ and executes the system-side hunting detection process HD _1A. The execution of the suppression control CNT ₃ may be canceled by determining that the cancellation condition is satisfied when the occurrence of the phenomenon is observed a predetermined number of times (an arbitrary number of 1 or more). Similarly, during the execution period of the system output quantitative control or the system input quantitative control and the suppression control CNT ₃ , the control unit 23 executes the power storage side hunting detection process HD _1C , and the power storage side hunting phenomenon occurs a predetermined number of times (1 It may be determined that the release condition has been satisfied when the number of observations above is observed, and the execution of the suppression control CNT ₃ may be released.

That is, the control unit 23 determines whether or not the switching operation between the input process and the output process has been performed a predetermined number of times during the execution of the hunting suppression control CNT ₃ , and if it is determined that the switching operation has been performed the predetermined number of times, The suppression control CNT ₃ may be configured to end. The predetermined number may be one or more.

3. Operation Flowchart Next, an operation flow of the power conversion device 2a will be described with reference to FIG. FIG. 30 is an operation flowchart of the power conversion device 2a focusing on the above-described various quantitative controls. Steps S31 to S33, S35 and S36 are the same as steps S11 to S13, S15 and S16 of FIG. 19, respectively.

First, in step S31, the control unit 23 starts executing any quantitative control.

Thereafter, in step S32, the control unit 23 performs the above-described hunting detection process or prediction process based on the input / output power information.

In subsequent step S33, the control unit 23 checks whether the hunting detection determination or the prediction determination is made, and if any of the determinations is made, the control unit 23 shifts to step S34 to perform the hunting suppression control CNT ₃ . Execution is started (that is, charging / discharging for suppressing hunting is performed by the power storage device 3a).

After the execution of the hunting suppression control CNT ₃ is started, the control unit 23 performs a hunting suppression control CNT ₃ release possibility determination process (J _1A , J _1B , J _1C or J _1D ) (step S35).

Control unit 23 continues the execution of the hunting suppression control CNT ₃ until either the predetermined release condition is satisfied (step S35 and S36), the execution of the is confirmed fulfillment of releasing condition hunting suppression control CNT ₃ Cancel (step S37) and return to step S32.

As described above, (charging and discharging of the power storage device 3a) charging and discharging for hunting suppressed by canceling the execution of the hunting suppression control CNT ₃ is stopped.

4). Features of Power Converter 2 of the Present Embodiment The power converter 2 (2a) of the present embodiment has the following first features. In the first feature, the power conversion device 2 a includes a power conversion circuit 20 (20 a) and a control unit 23. The power conversion circuit 20a includes a first power storage side circuit (power conversion unit 21B) connected to the first power storage device 3 capable of charging and discharging, and a second power source connected to the second power storage device 3a capable of charging and discharging. A power storage side circuit (power conversion unit 21Ba), a power generation side circuit (power conversion unit 21G) connected to the power generation device 4 that generates power and outputs generated power, and a system side circuit (power conversion unit) connected to the power system 5 21S). The power conversion circuit 20a is configured to transmit and receive power between the first power storage device 3, the second power storage device 3a, the power generation device 4, and the power system 5 through power conversion. The control unit 23 is configured to control power transmission and power reception by controlling the power conversion circuit 20a. The controller 23 absorbs the shortage or surplus of the generated power at the input / output of power between the power conversion circuit 20a and the power system 5, and uses the generated power of the power generation device 4 to keep the first power storage device 3 constant. Or supplying power to at least one of the load and the secondary battery connected to the power conversion circuit 20a using the generated power of the power generation device 4 and the discharge power of the first power storage device 3. Quantitative control for discharging the first power storage device 3 under a certain second reference condition is performed. In the quantitative control, when the input / output switching between the power conversion circuit 20a and the power system 5 is detected more than a predetermined number of times within a predetermined time, or the generated power amount of the power generation device 4 or a value corresponding to the generated power amount When the occurrence of switching is predicted based on the first reference condition or the second reference condition, the control unit 23 outputs power from the power conversion circuit 20a to the second power storage device 3a or power from the second power storage device 3a. The suppression control which suppresses switching by performing the electric power input to the conversion circuit 20a is performed.

The power conversion device 2 (2a) of the present embodiment has the following second feature. In the second feature, the power conversion device 2 a includes a power conversion circuit 20 (20 a) and a control unit 23. The power conversion circuit 20a includes a first power storage side circuit (power conversion unit 21B) connected to the first power storage device 3 capable of charging and discharging, and a second power source connected to the second power storage device 3a capable of charging and discharging. A power storage side circuit (power conversion unit 21Ba), a power generation side circuit (power conversion unit 21G) connected to the power generation device 4 that generates power and outputs generated power, and a system side circuit (power conversion unit) connected to the power system 5 21S). The power conversion circuit 20a is configured to transmit and receive power between the first power storage device 3, the second power storage device 3a, the power generation device 4, and the power system 5 through power conversion. The control unit 23 is configured to control power transmission and power reception by controlling the power conversion circuit 20a. The control unit 23 absorbs the deficiency or surplus of the generated power by charging or discharging the first power storage device 3 and uses the generated power of the power generation device 4 to transfer the constant power from the power conversion circuit 20a to the power system 5. Power is output under one reference condition, or power is supplied to at least one of a load and a secondary battery connected to the power conversion circuit 20a using generated power and input power from the power system 5 to the power conversion circuit 20a. Quantitative control for inputting electric power from the power system 5 to the power conversion circuit 20a under a constant second reference condition is performed. In the quantitative control, when switching of power input / output between the power conversion circuit 20a and the first power storage device 3 is detected more than a predetermined number of times within a predetermined time, or depending on the generated power amount or the generated power amount of the power generating device 4 When occurrence of switching is predicted based on the measured value and the first reference condition or the second reference condition, the control unit 23 outputs power from the power conversion circuit 20a to the second power storage device 3a or the second power storage device 3a. The suppression control which suppresses switching by performing the electric power input to the power converter circuit 20a from is performed.

The power conversion device 2 of the present embodiment has the following third feature in addition to the first or second feature. In the third feature, the control unit 23 performs the control based on the value of the generated power amount or the generated power amount of the power generation device 4 and the first reference condition or the second reference condition during the execution period of the suppression control. When it is determined that the release condition is satisfied, the execution of the suppression control is released.

The power conversion device 2 of the present embodiment has the following fourth feature in addition to the first or second feature. In the fourth feature, the control unit 23 cancels the execution of the suppression control when switching is detected during the execution period of the suppression control.

In addition, the power converter device 2 should just have at least 1 of a 1st characteristic and a 2nd characteristic. The third and fourth features are optional features.

As described above, the hunting suppression control CNT ₃ according to the third embodiment also has an adverse effect on the system-side hunting phenomenon or the power storage device 3 that affects the stability of the power system 5 as in the first embodiment. It is possible to appropriately suppress the storage-side hunting phenomenon that may be applied. Therefore, according to the present embodiment, it is possible to provide the power conversion device 2a that contributes to the suppression of the hunting phenomenon.

Further, since the hunting suppression control CNT ₃ in the third embodiment does not affect the quantitative control, the desired quantitative control can be continued during the execution period of the hunting suppression control CNT ₃ . However, the hunting suppression control CNT ₃ of the third embodiment causes the power storage device 3a to perform charge / discharge that is not originally required. In this regard, whether or not the release condition is satisfied is monitored when the hunting suppression control CNT ₃ is executed, and the hunting suppression control CNT ₃ is released when it is determined that the hunting phenomenon does not occur or hardly occurs even when the execution is canceled. By adopting the method, unnecessary charging / discharging can be suppressed as much as possible while avoiding the hunting phenomenon as much as possible.

Note that, when the hunting detection process is used without using the hunting prediction process, the hunting suppression control is executed after the occurrence of the hunting phenomenon is detected, so that some hunting phenomenon is allowed to occur. On the other hand, if the hunting prediction process is used, the occurrence of the hunting phenomenon can be completely or almost completely avoided. However, when the hunting prediction process is used, the unnecessary charge / discharge execution time increases as compared with the case where the hunting detection process is used, and the efficiency of the entire system is reduced (power conversion associated with unnecessary charge / discharge). Loss reduces overall system efficiency). Whether to execute the hunting detection process or the prediction process may be set according to which of the hunting phenomenon suppression and the system efficiency is given priority.

Moreover, which of the two power storage devices provided in the power supply system 1a is set as the power storage device 3 and which is set as the power storage device 3a is arbitrary. The control unit 23 may perform a selection process of selecting any one of the two power storage devices as the power storage device 3 and selecting the other as the power storage device 3a. The control unit 23 may obtain the degree of deterioration (for example, SOH (State Of Health)) of each of the two power storage devices and perform the selection process according to the degree of deterioration. Further, in the hunting suppression control CNT ₃ , it may be fixed in advance whether the power storage device 3 a is to be charged or discharged, or the control unit 23 may determine according to the remaining capacity of the power storage device 3 a. It may be determined.

(Deformation etc.)
The embodiment of the present invention can be appropriately modified in various ways within the scope of the technical idea shown in the claims. The above embodiment is merely an example of the embodiment of the present invention, and the meaning of the term of the present invention or each constituent element is not limited to that described in the above embodiment. The specific numerical values shown in the above description are merely examples, and as a matter of course, they can be changed to various numerical values. As annotations applicable to the above-described embodiment, notes 1 to 8 are described below. The contents described in each comment can be arbitrarily combined as long as there is no contradiction.

(Note 1)
In each of the above-described embodiments, it is assumed that the charging reference condition specifies that the charging power amount of the power storage device 3 is constant, and accordingly, the charge quantitative control keeps the charging power amount of the power storage device 3 constant. Assumed to be control. However, as long as charge quantitative control is what charges the electrical storage apparatus 3 on fixed charge reference conditions, charge quantitative control is not limited to what was illustrated in each embodiment. That is, for example, the charge quantitative control may be control (constant current charge control) for charging the power storage device 3 with a constant current value, or control for charging the power storage device 3 with a constant voltage value (constant voltage charge control). ). Similarly, as long as the discharge quantitative control is to discharge the power storage device 3 under a certain discharge reference condition, the discharge quantitative control is not limited to those exemplified in each embodiment. 3 may be controlled to discharge at a constant current value (constant current discharge control).

Similarly, as long as the system output quantitative control is to output power from the power conversion circuit (20 or 20a) to the power system 5 under a certain system output reference condition, the system output quantitative control is as exemplified in each embodiment. For example, the system output quantitative control may be control that keeps the output current value (effective value) from the power conversion circuit (20 or 20a) to the power system 5 constant. Similarly, as long as the system input quantitative control is to input power from the power system 5 to the power conversion circuit (20 or 20a) under a certain system input reference condition, the system input quantitative control is as illustrated in each embodiment. For example, the system input quantitative control may be control that keeps the input current value (effective value) from the power system 5 to the power conversion circuit (20 or 20a) constant.

(Note 2)
As can be understood from the description in Note 1, in charge quantitative control, the control unit 23 determines the charge current supplied from the power conversion unit 21B to the power storage device 3 instead of the charge command amount P _B ^* for power. The charge command amount I _B ^* designating the current value I _B may be generated and given to the power conversion unit 21B. The power conversion unit 21B has a charge current having a current value designated by the charge command amount I _B ^* . May be converted to supply power to the power storage device 3. In the charge quantitative control, the control unit 23 can charge the power storage device 3 with a constant reference current amount I _BREF for storage by substituting the value of the reference current amount I _BREF for storage into the charge command amount I _B ^*. . In this case, the charge reference condition specifies that the power storage device 3 is charged with a constant reference current amount I _BREF for power storage. In this specification, the term “current value” and the term “current amount” are synonymous, and the term “voltage value” and the term “voltage amount” are synonymous.

Similarly, in the discharge quantitative control, the control unit 23 generates a discharge command amount I _B ^* that specifies the current value I _B of the discharge current of the power storage device 3 instead of the discharge command amount P _B ^* for power. The power conversion unit 21B may perform the discharge power conversion so that a discharge current having a current value specified by the discharge command amount I _B ^* is output from the power storage device 3. Also good. In the discharge quantitative control, the control unit 23 can discharge the power storage device 3 with a constant reference current amount I _BREF for storage by substituting the value of the reference current amount I _BREF for storage into the discharge command amount I _B ^*. . In this case, the discharge reference condition specifies that the power storage device 3 is discharged with a constant reference current amount I _BREF for power storage.

Similarly, in the grid output quantitative control, the control unit 23 designates the current value I _S of the output current from the power conversion unit 21S to the power system 5 instead of the grid output command amount P _S ^* for power. The command amount I _S ^* may be generated and given to the power conversion unit 21S. The power conversion unit 21S receives a current having a current value specified by the system output command amount I _S ^* from the power conversion unit 21S. System output power conversion may be performed so that the power is output to 5. In the system output quantitative control, the control unit 23 substitutes the value of the system reference current amount I _{SREF into} the system output command amount I _S ^* to transfer the current from the power conversion unit 21S to the power system 5 with a constant current amount I _SREF . Output can be performed. In this case, the grid output reference condition specifies that the power output from the power conversion circuit (20 or 20a) to the power grid 5 is performed with a constant grid reference current amount I _SREF .

Similarly, in the system input quantitative control, the control unit 23 specifies the current value I _S of the input current from the power system 5 to the power conversion unit 21S instead of the system input command amount P _S ^* for power. The command amount I _S ^* may be generated and given to the power conversion unit 21S. The power conversion unit 21S receives a current having a current value specified by the system input command amount I _S ^* from the power system 5 and converts it into a power conversion unit. System input power conversion may be performed so as to be input to 21S. In the system input quantitative control, the control unit 23 substitutes the value of the system reference current amount I _{SREF into} the system input command amount I _S ^* to transfer a current with a constant current amount I _SREF from the power system 5 to the power conversion unit 21S. Input can be made. In this case, the grid input reference condition specifies that the current input from the power grid 5 to the power conversion circuit (20 or 20a) is performed with a constant grid reference current amount I _SREF .

(Note 3)
The prediction processes HP _1A and HP _1B and the release possibility determination processes J _1A and J _1B using both the voltage value and the current value depending on the amount of power generated by the power generation device 4 have been described above. However, if the ratio between the voltage value V _G and the voltage value V _B , the ratio between the voltage value V _INT and the voltage value V _B , or the voltage values V _G , V _B and V _INT are known to the control unit 23. The control unit 23 uses only the information on the current value corresponding to the amount of power generated by the power generation device 4, that is, uses only the current value I _G or I _GINT to perform the prediction processes HP _1A and HP _1B and the _{cancelability} determination process J _1A and J _1B can also be formed. At this time, in the above-described processes HP _1A , HP _1B , J _1A and J _1B , arbitrary “power amount” and “symbol representing power amount” are set to “current value” and “current value” using known voltage information. The process realized through this conversion is equivalent to the processes HP _1A , HP _1B , J _1A and J _1B described above.

For example, if the power conversion efficiency of the

power conversion units

Similarly, the ratio between the voltage value V _G and the voltage value (effective value) V _S , the ratio of the voltage value V _INT and the voltage value (effective value) V _S , or the voltage values V _G , V _S and V _INT are controlled. If it is known to the unit 23, the control unit 23 can also perform the prediction processes HP _1C and HP _1D and the release possibility determination processes J _1C and J _1D using only the current value I _G or I _GINT . At this time, in the above-described processes HP _1C , HP _1C , J _1C and J _1D , arbitrary “power amount” and “symbol representing power amount” are set to “current value” and “current value” using information on known voltages. The process realized through this conversion is equivalent to the processes HP _1C , HP _1C , J _1C and J _1D described above.

Similarly, in the second embodiment, the ratio between the voltage value V _G and the voltage value V _B , the ratio between the voltage value V _INT and the voltage value V _{B, and} between the voltage value V _G and the voltage value (effective value) V _S. If the ratio, voltage value V _INT and voltage value (effective value) V _S , voltage values V _G , V _B and V _INT , or voltage values V _G , V _S and V _INT are known to the control unit 23 if, the control unit 23 can also form a release determination process J ₂ using only current value I _G or I _GINT. At this time, in the above-described release possibility determination process J ₂ , arbitrary “power amount” and “symbol representing power amount” are converted into “current value” and “symbol representing current value” using known voltage information. it is sufficient, processing realized through this transform is equivalent to the release determination process J ₂ above.

(Note 4)
As described above, in charging quantitative control, the charging condition of the power storage device 3 (hereinafter referred to as charging condition) is specified by the charging reference condition, and in discharging quantitative control, the discharging condition of the power storage device 3 (hereinafter referred to as discharging condition). Is specified in the discharge reference condition, and in the grid output quantitative control, the power output condition from the power conversion circuit (20 or 20a) to the power grid 5 (hereinafter referred to as the grid output condition) is specified in the grid output reference condition. In the system input quantitative control, the power input condition (hereinafter referred to as system input condition) from the power system 5 to the power conversion circuit (20 or 20a) is designated by the system input reference condition.

In the first embodiment, the specific method of the hunting suppression control CNT _1A for changing the charging condition from the charging reference condition is described, assuming that the charging reference condition defines the storage reference power amount P _BREF. The above-described method is only one method for changing the charging condition from the charging reference condition.

In other words, the suppression control CNT _1A can be realized by any method that can change the charging condition of the power storage device 3 (condition of the electric energy, current value, or voltage value in charging) from the charging reference condition. For example, in the charging quantitative control, when the control unit 23 has given current instruction values I _B ^* which specifies the current value I _B to the power conversion unit 21B, that is, the control unit 23 via the control of the current value I _B charge When the hunting suppression control CNT _1A is performed in the case where the quantitative control is realized, the control unit 23 changes the current command amount I _B ^* from the current value (I _BREF ) according to the charge reference condition, thereby changing the charge condition to the charge reference. You may change from conditions. Alternatively, for example, in the charging quantitative control, when the control unit 23 has given voltage command value V _B ^* that specifies the voltage value V _B to the power conversion unit 21B, that is, the control unit 23 via the control voltage value V _B When realizing the hunting suppression control CNT _1A when the charge quantitative control is realized, the control unit 23 changes the voltage command amount V _B ^* from the voltage amount V _BREF according to the charge reference condition, thereby changing the charge condition to the charge reference condition. (P _BREF = I _BREF × V _BREF ). In any case, a change in the charging condition by the suppression control CNT _1A is accompanied by a change in the amount of charge power of the power storage device 3 (for example, a change from P _BREF ).

Similarly, the suppression control CNT _1B can be realized by any method that can change the discharge condition of the power storage device 3 (the condition of the electric energy, current value, or voltage value in discharge) from the discharge reference condition. For example, in the discharge quantitative control, when the control unit 23 has given current instruction values I _B ^* which specifies the current value I _B to the power conversion unit 21B, that is, the control unit 23 via the control of the current value I _B discharge When realizing the hunting suppression control CNT _1B in the case of realizing the quantitative control, the control unit 23 changes the discharge condition by changing the current command amount I _B ^* from the current value (I _BREF ) according to the discharge reference condition. You may change from conditions. Alternatively, for example, in the discharge quantitative control, when the control unit 23 has given voltage command value V _B ^* that specifies the voltage value V _B to the power conversion unit 21B, that is, the control unit 23 via the control voltage value V _B When the hunting suppression control CNT _1B is performed in the case where the discharge quantitative control is realized, the control unit 23 changes the discharge condition by changing the voltage command amount V _B ^* from the voltage amount V _BREF according to the discharge reference condition. It may be changed from In any case, a change in the discharge condition by the suppression control CNT _1B is accompanied by a change in the amount of discharge power of the power storage device 3 (for example, a change from P _BREF ).

Each of P _B ^* , I _B ^*, and V _B ^* is a kind of command amount (charge / discharge command amount) that specifies a charging condition or a discharging condition. P _BREF , I _BREF, and V _BREF are all _types of reference amounts (charge / discharge reference amounts) according to the charge reference condition or the discharge reference condition.

Similarly, the suppression control CNT _1C changes the grid output condition (the condition of the electric energy, current value, or voltage value in the power output from the power conversion circuit (20 or 20a) to the power grid 5) from the grid output reference condition. It can be realized by an arbitrary method. For example, the channel output quantitative control, the current instruction values I _S ^* by the control unit 23 specifies the current value I _S If given to the power conversion unit 21S, i.e. the control unit 23 via the control of the current value I _S When the hunting suppression control CNT _1C is realized in the case where the system output quantitative control is realized, the control unit 23 changes the current command amount I _S ^* from the current value (I _SREF ) according to the system output reference condition to output the system output. The condition may be changed from the system output reference condition. Alternatively, for example, in the channel output quantitative control, when the control unit 23 has given voltage command value V _S ^* to specify the voltage value V _S to the power conversion unit 21S, i.e. the control unit 23 via the control voltage value V _S When the system output quantitative control is realized, when the hunting suppression control CNT _1C is performed, the control unit 23 changes the voltage command amount V _S ^* from the voltage amount V _SREF according to the system output reference condition, thereby generating the system output condition. _May be changed from the system output reference condition (P _SREF = I _SREF × V _SREF ). In any case, a change in the system output condition by the suppression control CNT _1C is accompanied by a change in the output power amount from the power conversion circuit (20 or 20a) to the power system 5 (for example, a change from P _SREF ).

Similarly, the suppression control CNT _1D changes the system input condition (the condition of the electric energy, current value, or voltage value in the power input from the power system 5 to the power conversion circuit (20 or 20a)) from the system input reference condition. It can be realized by an arbitrary method. For example, the system inputs quantitative control, the current instruction values I _S ^* by the control unit 23 specifies the current value I _S If given to the power conversion unit 21S, i.e. the control unit 23 via the control of the current value I _S When the hunting suppression control CNT _1D is performed in the case where the system input quantitative control is realized, the control unit 23 changes the current command amount I _S ^* from the current value (I _SREF ) according to the system input reference condition, thereby inputting the system input. The condition may be changed from the system input reference condition. Alternatively, for example, in the system input quantitative control, when the control unit 23 has given voltage command value V _S ^* to specify the voltage value V _S to the power conversion unit 21S, i.e. the control unit 23 via the control voltage value V _S When the system input quantitative control is realized, when the hunting suppression control CNT _1D is performed, the control unit 23 changes the voltage command amount V _S ^* from the voltage amount V _SREF according to the system input reference condition, thereby changing the system input condition. May be changed from the system input reference condition. In any case, a change in the grid input condition by the suppression control CNT _1D is accompanied by a change in the amount of input power from the power grid 5 to the power conversion circuit (20 or 20a) (for example, a change from P _SREF ).

P _S ^* , I _S ^*, and V _S ^* are all types of command quantities (system input / output command quantities) that specify system output conditions or system input conditions. P _SREF , I _SREF, and V _SREF are all types of reference quantities (system input / output reference quantities) according to system output reference conditions or system input reference conditions.

(Note 5)
The input / output power information to be acquired by the control unit 23 is not necessarily required to include all information indicating the voltage value, current value, and power amount. In the first to third embodiments, the input / output power information includes voltage information representing voltage values (that is, V _B , V _G , V _S and V _INT , or V _B , V _Ba , V _G , V _S and V _INT ), current information indicating a current value (ie, I _B , I _G , I _S , I _BINT , I _GINT and I _SINT , or I _B , I _Ba , I _G , I _S , I _BINT , I _BINTa , I _GINT and I _SINT ) and power information representing the amount of power (ie, P _B , P _G , P _S , P _BINT , P _GINT and P _SINT , or P _B , P _Ba , P _G , P _S , P _BINT , P _BINTa , P _GINT, and P _SINT ) as long as they include at least one piece of information.

(Note 6)
The power conversion units 21B, 21Ba, 21G, and 21S respectively include a first power storage side circuit, a second power storage side circuit, a power generation side circuit, and a system connected to the power storage device 3, the power storage device 3a, the power generation device 4, and the power system 5. This is an example of the side circuit, and the first power storage side circuit, the second power storage side circuit, the power generation side circuit, or the system side circuit further includes a circuit other than the circuit that forms the power conversion unit 21B, 21Ba, 21G, or 21S. May be.

(Note 7)
In each of the first to third embodiments, the DC load 8 and the secondary battery 8a may be connected to the intermediate wiring 22 as shown in FIG. The secondary battery 8a is composed of one or more secondary batteries of any type (for example, a lithium ion battery or a nickel metal hydride battery). The secondary battery 8a is a battery mounted on an electric vehicle such as an electric vehicle, for example. When the DC load 8 and the secondary battery 8a are connected to the intermediate wiring 22, in each of the above-mentioned explanations including the explanations of the first to third embodiments, the electric power sent to the DC load 8 and the DC load 8 and What is necessary is just to consider it as the electric power sent to the secondary battery 8a, that is, for example, the power consumption of the DC load 8 is regarded as the sum of the power consumption of the DC load 8 and the charging power of the secondary battery 8a and the power supplied to the DC load 8 May be regarded as the power supplied to the DC load 8 and the secondary battery 8a. When the DC load 8 and the secondary battery 8a are connected to the intermediate wiring 22, one or more power conversion units may be interposed between the intermediate wiring 22, the DC load 8, and the secondary battery 8a.

Alternatively, in each of the first to third embodiments, as shown in FIG. 32, a secondary battery 8 a may be connected to the intermediate wiring 22 instead of the DC load 8. In the configuration shown in FIG. 32, the DC load 8 is not connected to the intermediate wiring 22. In the case where the secondary battery 8a is connected to the intermediate wiring 22 without being connected to the DC load 8, the power sent to the DC load 8 in each of the above description including the description of the first to third embodiments What is necessary is just to regard the power sent to the secondary battery 8a, that is, for example, the power consumption of the DC load 8 is regarded as the charging power of the secondary battery 8a and the power supplied to the DC load 8 is the power supplied to the secondary battery 8a. You should consider it. When the secondary battery 8a is connected to the intermediate wiring 22 without connecting the DC load 8, a power conversion unit may be interposed between the intermediate wiring 22 and the secondary battery 8a.

(Note 8)
The control unit 23 can be configured by hardware or a combination of hardware and software. A function realized using software may be described as a program, and the function may be realized by executing the program on a program execution device (for example, a computer). Specifically, for example, a CPU (Central Processing Unit) is provided in the control unit 23, and a necessary function can be realized by causing the CPU to execute a program stored in a flash memory (not shown).

Claims

A power conversion circuit;
A control unit;
With
The power conversion circuit includes:
A power receiving function for receiving power from a power supply device;
A power transmission function for supplying power to the power demand device;
An input / output selection function for selectively executing output processing for supplying power to the power auxiliary device and input processing for acquiring power from the power auxiliary device;
In accordance with an instruction from the control unit, an adjustment function for adjusting at least one of supply power that is power received from the power supply device and demand power that is power supplied to the power demand device;
Have
The controller is
Comparing the supply power with the demand power;
If the supply power is greater than the demand power, the power conversion circuit is configured to execute the output process so that a surplus of the supply power is supplied to the power auxiliary device,
If the supply power is less than the demand power, the power conversion circuit is configured to execute the input process so that the shortage of the supply power is supplemented with the power from the power auxiliary device,
The controller is configured to determine whether or not an event that causes a hunting phenomenon has occurred in the power conversion circuit, and to execute hunting suppression control when determining that the event has occurred,
The said control part is comprised so that the said instruction | indication may be given to the said power converter circuit so that the difference of the said supplied power and the said demand power may become large in the said hunting suppression control.
The instruction is a target value of the demand power,
The power conversion circuit is configured to adjust the demand power to the target value when receiving the target value from the control unit,
The control unit is configured to perform normal control for setting the target value to a default value until it is determined that the event has occurred,
The power conversion device according to claim 1, wherein the control unit is configured to set the target value to a value different from the predetermined value in the hunting suppression control.
The power supply device is a power generation device,
The power demand device is one of a power storage device and a power system,
The power converter according to claim 2, wherein the power auxiliary device is the other of the power storage device and the power system.
The power supply device includes a power generation device and a power supply device,
The supplied power is a total of generated power that is power supplied from the power generator and power source power that is power obtained from the power supply device,
The instruction is a target value of the power supply power,
The power conversion circuit is configured to adjust the power supply power to the target value upon receiving the target value;
The control unit is configured to perform normal control for setting the target value to a default value until it is determined that the event has occurred,
The power conversion device according to claim 1, wherein the control unit is configured to set the target value to a value different from the predetermined value in the hunting suppression control.
The power supply device is one of a power storage device and a power system,
The power converter according to claim 4, wherein the power auxiliary device is one of the power storage device and the power system.
The power supply device includes a power generation device,
The supplied power includes generated power that is power obtained from the power generator,
The instruction is a target value of the generated power,
When the power conversion circuit receives the target value, the power conversion circuit is configured to control the power generation device so that the generated power becomes the target value.
The control unit is configured to perform normal control for setting the target value to a default value until it is determined that the event has occurred,
The power conversion device according to claim 1, wherein the control unit is configured to set the target value to a value different from the predetermined value in the hunting suppression control.
The power generation device is a solar cell,
The power conversion device according to claim 6, wherein the power conversion circuit is configured to adjust the generated power by changing an operating point of the solar cell in accordance with the instruction.
The power conversion device according to claim 7, wherein the predetermined value is a value corresponding to the maximum power of the solar cell.
The power demand device is one of a power storage device and a power system,
The power converter according to claim 6, wherein the power auxiliary device is one of the power storage device and the power system.
The power supply device further includes a power supply device,
The supplied power is a total of generated power that is power supplied from the power generator and power source power that is power obtained from the power supply device,
The power supply device is one of a power storage device and a power system,
The power converter according to claim 6, wherein the power auxiliary device is one of the power storage device and the power system.
The power conversion circuit has a second input / output selection function for selectively executing a second output process and a second input process,
The power conversion circuit is configured to increase the demand power by using the second power auxiliary device as a part of the power demand device by supplying power to the second power auxiliary device in the second output process. And
In the second input process, the power conversion circuit obtains power from the second power auxiliary device to increase the supply power by using the second power auxiliary device as a part of the power supply device. Configured,
The hunting suppression control includes a first hunting suppression control that causes the power conversion circuit to execute the second output process, and a second hunting suppression control that causes the power conversion circuit to execute the second input process.
When the control unit determines that the event has occurred, the control unit executes any one of the first hunting suppression control and the second hunting suppression control so that a difference between the supplied power and the demand power is increased. It is comprised by these. The power converter device of Claim 1 characterized by the above-mentioned.
The second power auxiliary device is a second power storage device,
The power conversion circuit is configured to charge the second power storage device in the second output process and to discharge the second power storage device in the second input process. Power converter.
The control unit is configured to compare the remaining amount of power of the second power storage device with a predetermined value when it is determined that the event has occurred,
The control unit is configured to execute the first hunting suppression control if the remaining amount is less than the predetermined value, and to execute the second hunting suppression control if the remaining amount is equal to or greater than the predetermined value. The power conversion device according to claim 12, wherein
The power supply device is a power generation device,
The power demand device is one of a power storage device and a power system,
The power converter according to claim 11, wherein the power auxiliary device is one of the power storage device and the power system.
The power supply device includes a power generation device and a power supply device,
The power supply device is one of a power storage device and a power system,
The power converter according to claim 11, wherein the power auxiliary device is one of the power storage device and the power system.
The control unit is configured to end the hunting suppression control when a difference between the supplied power and the demand power satisfies a release condition during execution of the hunting suppression control. Item 4. The power conversion device according to Item 1.
The release condition is that the absolute value of the difference between the supplied power and the demand power is not more than a predetermined threshold, or the absolute value of the difference between the supply power and the demand power is not more than a predetermined threshold Has continued for a predetermined time,
The power conversion device according to claim 16, wherein the predetermined threshold value is smaller than a change width of a difference between the supplied power and the demand power due to the execution of the hunting suppression control.
The power conversion apparatus according to claim 16, wherein the cancellation condition is that a state where a difference between the supplied power and the demand power is positive or negative continues for a predetermined time.
The control unit is configured to end the hunting suppression control when a difference between the supplied power and the predetermined value satisfies a release condition during execution of the hunting suppression control,
The release condition is
The absolute value of the difference is greater than or equal to a threshold,
A state in which the absolute value of the difference is equal to or greater than the threshold continues for a predetermined first time;
Or that the difference is positive or negative for a predetermined second time period,
It is either of these. The power converter device of Claim 2 characterized by the above-mentioned.
The control unit ends the hunting suppression control when a difference between a total value of the generated power and the predetermined value and the demand power satisfies a release condition during the execution of the hunting suppression control. Configured,
The release condition is
The absolute value of the difference is greater than or equal to a threshold,
A state in which the absolute value of the difference is equal to or greater than the threshold continues for a predetermined first time;
Or that the difference is positive or negative for a predetermined second time period,
It is either of these. The power converter device of Claim 4 characterized by the above-mentioned.
The control unit is configured to end the hunting suppression control when a difference between the demand power and the predetermined value satisfies a release condition during execution of the hunting suppression control,
The release condition is
The absolute value of the difference is greater than or equal to a threshold,
A state in which the absolute value of the difference is equal to or greater than the threshold continues for a predetermined first time;
Or that the difference is positive or negative for a predetermined second time period,
It is either of these. The power converter device of Claim 9 characterized by the above-mentioned.
The control unit ends the hunting suppression control when the difference between the total value of the power source power and the predetermined value and the demand power satisfies the release condition during the execution of the hunting suppression control. Configured,
The release condition is
The absolute value of the difference is greater than or equal to a threshold,
A state in which the absolute value of the difference is equal to or greater than the threshold continues for a predetermined first time;
Or that the difference is positive or negative for a predetermined second time period,
It is either of these. The power converter device of Claim 10 characterized by the above-mentioned.
The power conversion circuit is configured to increase the demand power from a first predetermined value in the second output process,
The control unit is configured to end the first hunting suppression control when a difference between the supplied power and the first predetermined value satisfies a first release condition during execution of the first hunting suppression control. And
The first release condition is
A first absolute value of a difference between the supplied power and the first predetermined value is not less than a first threshold;
A state in which the first absolute value is equal to or greater than the first threshold has continued for a predetermined first time;
Alternatively, a state where a difference between the supplied power and the first predetermined value is positive or negative continues for a predetermined second time,
It is either of these. The power converter device of Claim 11 characterized by the above-mentioned.
The power conversion circuit is configured to increase the supply power from a second predetermined value in the second input process,
The control unit is configured to end the second hunting suppression control when a difference between the demand power and the second predetermined value satisfies a second release condition during execution of the second hunting suppression control. And
The second release condition is:
A second absolute value of a difference between the demand power and the second predetermined value is not less than a second threshold;
The state in which the second absolute value is equal to or greater than the second threshold has continued for a predetermined third time;
Alternatively, a state where a difference between the demand power and the second predetermined value is positive or negative has continued for a predetermined fourth time,
It is either of these. The power converter device of Claim 11 characterized by the above-mentioned.
The controller determines whether or not the switching operation between the input process and the output process has been performed a predetermined number of times during the execution of the hunting suppression control, and determines that the switching operation has been performed a predetermined number of times, The power conversion device according to claim 1, wherein the power conversion device is configured to end the hunting suppression control.
The control unit is configured to determine that the event has occurred when the power conversion circuit performs a switching operation between the output process and the input process a predetermined number of times within a predetermined time. The power conversion device according to claim 1.
The control unit determines whether or not an absolute value of a difference between the supplied power and the demand power is equal to or less than a determination value, and the event occurs when it is determined that the absolute value is equal to or less than the determination value. The power conversion device according to claim 1, wherein the power conversion device is configured to determine that the power conversion has occurred.
The control unit determines whether or not a state in which an absolute value of a difference between the supplied power and the demand power is equal to or less than a determination value has continued for a determination time, and determines that the state has continued for the determination time The power conversion device according to claim 1, wherein the power conversion device is configured to determine that the event has occurred.