JP2013230000A - Power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply system that ensures more power available to a particular power consuming device than power available to other power consuming devices.SOLUTION: The power supply system capable of supplying power to a plurality of power consuming devices 4 supplies a first power consuming device 4A with at least any of discharge power from a first power storage device 5A, power from an external power system 1, and power from a power generation device 3, within the range of power consumption of the first power consuming device 4A, and supplies a second power consuming device 4B with at least any of discharge power from a second power storage device 5B, power from the external power system 1, and power from the power generation device 3, within the range of power consumption of the second power consuming device 4B. A control device C gives a charging command to the first power storage device 5A prior to a charging command to the second power storage device 5B, and gives a discharging command to the second power storage device 5B prior to a discharging command to the first power storage device 5A.

Description

  The present invention controls operations of a power line connected to an external power system, a power generation device capable of supplying generated power to the power line, a plurality of power storage devices connected to the power line, and a plurality of power storage devices. The present invention relates to a power supply system that includes a control device and that can supply power supplied from at least one of an external power system, a power generation device, and a power storage device to a plurality of power consuming devices.

Patent Document 1 describes the operation of a power line connected to an external power system, a power generation device capable of supplying generated power to the power line, a plurality of power storage devices connected to the power line, and a plurality of power storage devices. There is described a power supply system that includes a control device for controlling and that can supply power supplied from at least one of an external power system, a power generation device, and a power storage device to a plurality of power consuming devices. Specifically, in the power supply system described in Patent Document 1, the operation mode of the power storage device is determined to be one of a charge mode for charging until full charge is reached, or a discharge mode for discharging until discharge is completed, When the discharge of the power storage device determined to be in the discharge mode is completed, the power storage device is determined to be in the charge mode, and when the power storage device determined to be in the charge mode reaches full charge, the power storage device is set to the discharge mode. Decisions are made.
The electric power stored in the plurality of power storage devices is shared by the plurality of power consumption devices.

JP 2006-262612 A

Multiple power consuming devices are important loads such as lighting devices that need to be lit in an emergency such as a power outage, information equipment that needs to be always in operation, air conditioners, and lighting devices that are not so important. Etc., and can be classified into devices having the next highest importance after the important load.
However, in the power supply system described in Patent Document 1, since the power stored in the plurality of power storage devices is shared by the plurality of power consumption devices, for example, even in an emergency, all the power consumption devices are not distinguished. Power can be consumed, and power is not preferentially supplied to important loads. Therefore, there is a problem that the electric power that can be used by the important load becomes relatively small in an emergency. That is, the power supply system described in Patent Literature 1 cannot secure more power that can be used by a specific power consuming device such as an important load than power that can be used by other power consuming devices. There are issues in terms.

  The present invention has been made in view of the above problems, and its purpose is to secure more power that can be used by a specific power consuming device than power that can be used by other power consuming devices. It is in providing a power supply system that can perform the above.

In order to achieve the above object, the power supply system according to the present invention is characterized by a power line connected to an external power system, a power generator capable of supplying generated power to the power line, and a power line connected to the power line separately. A plurality of power storage devices, and a control device that controls the operation of the plurality of power storage devices, the power supplied from at least one of the external power system, the power generation device, and the power storage device A power supply system capable of supplying a plurality of power consuming devices,
At least one first power consuming device of the plurality of power consuming devices is connected to one or two or more first power stor- age devices among the plurality of power storing devices,
The other one or two or more second power storage devices in the plurality of power storage devices are connected to at least one second power consumption device in the plurality of power consumption devices,
The first power consuming device includes power discharged from the first power storage device within a range not exceeding power consumption of the first power consuming device, and power supplied from the external power system via the power line. , At least one of the power supplied from the power generation device via the power line is supplied,
The second power consuming device includes power discharged from the second power storage device within a range not exceeding power consumption of the second power consuming device, and power supplied from the external power system via the power line. , At least one of the power supplied from the power generation device via the power line is supplied,
The control device is configured to give a command to give a charge operation command to the first power storage device in preference to a charge operation command to the second power storage device, and a discharge operation command to the second power storage device. The point is to perform at least one of the control to give priority over the command of the discharge operation to the first power storage device.

According to the above characteristic configuration, the power stored in the first power storage device is selectively supplied to the first power consumption device, and the power stored in the second power storage device is supplied to the second power consumption device. Selectively supplied. That is, the electric power stored in the first power storage device is not the power shared by the plurality of power consuming devices, but the power that can be used only by the first power consuming device, and similarly stored in the second power storage device. The power that is present is power that can be used only by the second power consuming device. As a result, even in an emergency such as a power failure, the power that can be used by the first power consuming device can be reliably secured by the first power storage device, and the power that can be used by the second power consuming device is It can be ensured by two power storage devices.
Further, when the control device performs control to give a command for charging operation to the first power storage device in preference to a command for charging operation to the second power storage device, the amount of power stored in the first power storage device The increase is promoted more than the increase in the amount of power stored in the second power storage device. Further, when the control device performs control to give a command for the discharge operation to the second power storage device in preference to the command for the discharge operation to the first power storage device, the amount of power stored in the second power storage device The reduction is promoted more than the reduction in the amount of power stored in the first power storage device. Therefore, regardless of which control is performed, the first power storage device can store a relatively larger amount of power than the second power storage device.
Therefore, it is possible to provide a power supply system that can secure more power that can be used by a specific power consuming device than power that can be used by other power consuming devices.

Another characteristic configuration of the power supply system according to the present invention is that the power generator supplies the power line with generated power generated by following the load power required by the power line,
When the total power consumed by the plurality of power consuming devices is smaller than the set power for charging and the generated power of the power generating device is smaller than the set power for charging, the control device is at least one of the plurality of power storage devices. When the total power consumed by the plurality of power consuming devices is greater than the set power for discharging that is equal to or greater than the set power for charging, the generated power of the power generating device is used for the discharge. If it is equal to or higher than the set power, a discharge operation command is to be given to at least one of the plurality of power storage devices.

The power generation efficiency of the power generation device changes according to the magnitude of the generated power. Therefore, it is preferable to operate the power generation device in an operation state where the power generation efficiency is high.
In this feature configuration, the amount of load power required on the power line is obtained by subtracting the total discharge power from the plurality of power storage devices from the sum of the total power consumption by the plurality of power consumption devices and the total charge power from the plurality of power storage devices. It becomes the value. That is, the control device can change the magnitude of the load power required on the power line by causing the plurality of power storage devices to perform a discharging operation or a charging operation or not to perform a discharging operation or a charging operation. Also, in this feature configuration, the power generated by the power generator changes following the load power required by the power line, so if the load power required by the power line changes, the power generated by the power generator follows the change. The power changes. Therefore, the control device can command the charging operation and the discharging operation to the plurality of power storage devices, so that the generated power of the power generation device can be indirectly changed.
In particular, in this feature configuration, if the total power consumed by the plurality of power consuming devices is smaller than the set power for charging and the generated power of the power generating device is smaller than the set power for charging, the control device is at least one of the plurality of power storage devices. By giving a command for charging operation to the stand, the load power required by the power line is changed so as to increase, and as a result, the generated power of the power generator can be brought close to the set power for charging and The power generated by the power generation device can be stored in the power storage device. Similarly, if the total power consumed by the plurality of power consuming devices is greater than the set power for discharge and the generated power of the power generator is greater than or equal to the set power for discharge, at least one of the plurality of power storage devices is instructed to perform a discharge operation. As a result, the load power required by the power line is changed to be smaller, and as a result, the generated power of the power generation device is brought closer to the set power for discharge or the power supplied from the external power system is reduced. be able to.

  Still another characteristic configuration of the power supply system according to the present invention is that when the control device is to give a command for a charging operation to at least one of the plurality of power storage devices, the first power storage device is A charging operation command is provided on the condition that the amount of electricity stored in the first power storage device is smaller than a first set upper limit value, and the amount of power stored in the first power storage device is The charging operation command is provided on condition that the amount of power stored in the second power storage device is equal to or greater than the first set upper limit value and smaller than the second set upper limit value.

  According to the above characteristic configuration, when the control device commands a charging operation to at least one of the plurality of power storage devices, the first power storage device is independent of the amount of power stored in the second power storage device. A charging operation is performed in order to make the amount of power stored in the first power storage device equal to or greater than the first set upper limit value. In contrast, the second power storage device is not charged unless the amount of power stored in the first power storage device is equal to or greater than the first set upper limit value. That is, when a command for a charging operation is given to the first power storage device, there is no restriction due to the amount of power stored in the second power storage device, but when a command for a charging operation is given to the second power storage device, the power storage of the first power storage device is performed. You will be restricted by the amount. As a result, when a command for charging operation is to be given to a plurality of power storage devices, the command for charging operation is given to the first power storage device in preference to the second power storage device. Therefore, priority can be given to bringing the amount of electricity stored in the first power storage device to the first set upper limit value or more.

  Yet another characteristic configuration of the power supply system according to the present invention is such that the first power storage device discharges power corresponding to the power consumption of the first power consuming device when a command for discharging operation is given. The second power storage device is configured to discharge power corresponding to the power consumption of the second power consuming device when a command for a discharging operation is given, and the control device is configured to discharge at least one of the plurality of power storage devices. When it is intended to give a command for the discharge operation to one of the two power storage devices, the amount of power stored in the second power storage device is not less than or equal to a second set lower limit value, and the second power Even if the power consumption of the consuming device is not zero, and the second power storage device discharges the power corresponding to the power consumption of the second power consuming device, the generated power of the power generating device does not change the set power for discharge. If not less than The first power storage device is in a discharging operation, and the amount of power stored in the first power storage device is not less than or equal to a first set lower limit value. And even if the power consumption of the first power consuming device is not zero and the first power storage device discharges power corresponding to the power consumed by the first power consuming device, The point is that a discharge operation command is given on condition that the power does not fall below the set power for discharge.

  According to the above characteristic configuration, when the control device attempts to give a discharge operation command to at least one of the plurality of power storage devices, the state of the first power storage device is the second power storage device. Regardless, the amount of electricity stored in the second power storage device is not less than or equal to the second set lower limit value (this second set lower limit value means the minimum amount of electricity required for the second power storage device), and the second power The power consumption of the power generator is not zero, and even if the second power storage device discharges power corresponding to the power consumed by the second power consumer, the power generated by the power generator does not fall below the set power for discharge. The discharge operation is performed as a condition. On the other hand, for the first power storage device, if the second power storage device is not in a discharging operation, the amount of power stored in the first power storage device is not more than a first set lower limit value (this first set lower limit value is The power consumption of the first power consuming device is not zero), and the power consumption of the first power consuming device is not zero. Even if the power corresponding to is discharged, the discharge operation is not performed even if the condition that the generated power of the power generator does not fall below the set power for discharge is satisfied. That is, when giving a command for the discharge operation to the second power storage device, there is no restriction depending on the state of the first power storage device, but when giving a command for the discharge operation to the first power storage device, there is a restriction depending on the state of the second power storage device. Will receive. As a result, when a discharge operation command is to be given to a plurality of power storage devices, the discharge operation command is given to the second power storage device in preference to the first power storage device. Therefore, the amount of power stored in the second power storage device is reduced in preference to the amount of power stored in the first power storage device, and as a result, the amount of power stored in the first power storage device can be left relatively large.

  According to still another characteristic configuration of the power supply system according to the present invention, the first power storage device performs a discharge operation by adjusting the magnitude of the discharge power regardless of the magnitude of the power consumption of the first power consumption device. And the second power storage device is configured to be able to perform a discharge operation by adjusting the magnitude of discharge power regardless of the magnitude of power consumption of the second power consumption device. When the control device tries to give a discharge operation command to at least one of the plurality of power storage devices, the second power storage device has a second power storage amount equal to the second power storage device. The second power consuming device so that the generated power of the power generating device becomes the set power for discharge on condition that the power consumption of the second power consuming device is not zero or less and is not zero. Less than the power consumption range A discharge operation command with a discharge power is provided, and the first power storage device has a storage amount of zero in the second power storage device or the second power storage device is in a discharge operation, and On the condition that the amount of electricity stored in the first power storage device is not less than or equal to the first set lower limit value and the power consumption of the first power consuming device is not zero, the generated power of the power generation device is the set power for discharge. The point is to give a command for the discharge operation with the discharge power in the range less than the power consumption of the first power consuming device.

  According to the above characteristic configuration, when the control device attempts to give a discharge operation command to at least one of the plurality of power storage devices, the state of the first power storage device is the second power storage device. Regardless, the discharging operation is performed on condition that the amount of power stored in the second power storage device is not less than or equal to the second set lower limit value and that the power consumption of the second power consuming device is not zero. On the other hand, for the first power storage device, if the power storage amount of the second power storage device is zero or the second power storage device is not in a discharging operation, the power storage amount of the first power storage device is set to the first setting. Even if the condition that the power consumption of the first power consuming device is not lower than the lower limit value and that the power consumption is not zero is satisfied, the discharging operation is not performed. That is, when giving a command for the discharge operation to the second power storage device, there is no restriction depending on the state of the first power storage device, but when giving a command for the discharge operation to the first power storage device, there is a restriction depending on the state of the second power storage device. Will receive. As a result, when a discharge operation command is to be given to a plurality of power storage devices, the discharge operation command is given to the second power storage device in preference to the first power storage device. Therefore, the amount of power stored in the second power storage device is reduced in preference to the amount of power stored in the first power storage device, and as a result, the amount of power stored in the first power storage device can be left relatively large.

It is a figure explaining the structure of an electric power supply system. It is a flowchart explaining operation | movement of the electrical storage apparatus in 1st Embodiment. It is a flowchart explaining operation | movement of the electrical storage apparatus in 1st Embodiment. It is a figure explaining the relationship between the power consumption of the power consuming apparatus in 1st Embodiment, the charging / discharging operation | movement of an electrical storage apparatus, and the generated electric power of a fuel cell. It is a flowchart explaining operation | movement of the electrical storage apparatus in 2nd Embodiment. It is a flowchart explaining operation | movement of the electrical storage apparatus in 2nd Embodiment. It is a figure explaining the relationship between the power consumption of the power consuming apparatus in 2nd Embodiment, the charging / discharging operation | movement of an electrical storage apparatus, and the generated electric power of a fuel cell.

<First Embodiment>
The configuration of the power supply system according to the first embodiment will be described below with reference to the drawings.
FIG. 1 is a diagram illustrating a configuration of a power supply system. As shown in FIG. 1, the power supply system is connected to the power line 2 connected to the external power system 1, the fuel cell 3 as a power generator capable of supplying generated power to the power line 2, and the power line 2 separately. And a control device C that controls the operation of the plurality of power storage devices 5. The plurality of power consuming devices 4 can be supplied with power supplied from at least one of the external power system 1, the fuel cell 3, and the power storage device 5.

  A plurality of power consuming devices 4 are connected to the downstream side of the branch part 10 of the power line 2 (that is, the side farther from the external power system 1 than the branch part 10). In the present embodiment, the first power line 2A, the second power line 2B, and the third power line 2C are connected in parallel to the downstream side of the branch site 10, and the first power consumption device 4A is connected to the first power line 2A. The second power consumption device 4B is connected to the second power line 2B, and the third power consumption device 4C is connected to the third power line 2C.

The first power consuming device 4A has a degree of importance such as a lighting device that needs to be lit in an emergency such as a power outage or an information device that needs to be constantly operated among the plurality of power consuming devices 4. Includes expensive equipment. The power consumption of the first power consuming device 4A can be measured using the first power measuring means 6 provided on the first power line 2A. The measurement result by the first power measuring means 6 is transmitted to the control device C.
The second power consuming device 4B includes devices having the next highest importance after the first power consuming device 4A, such as an air conditioner and a lighting device that is not so important. The power consumption of the second power consuming apparatus 4B can be measured using the second power measuring means 7 provided on the second power line 2B. The measurement result by the second power measuring means 7 is transmitted to the control device C.
The third power consuming device 4C includes other devices not included in the first power consuming device 4A and the second power consuming device 4B. The power consumption of the third power consuming apparatus 4C can be measured using the third power measuring means 8 provided on the third power line 2C.

In the first power line 2A, a first power storage device 5A is provided on the upstream side of the portion where the first power measuring means 6 is provided. That is, at least one first power consuming device 4 </ b> A among the plurality of power consuming devices 4 is connected to one first power stor- age device 5 </ b> A among the plurality of power storing devices 5. As will be described later, control device C commands to stop charging operation, discharging operation, and charging / discharging operation of first power storage device 5A.
In the second power line 2B, a second power storage device 5B is provided on the upstream side of the portion where the second power measuring means 7 is provided. That is, at least one second power consuming device 4B among the plurality of power consuming devices 4 is connected to the other second power stor- ing device 5B among the plurality of power storing devices 5. The control device C commands the stop of the charging operation, the discharging operation, and the charging / discharging operation of the second power storage device 5B as will be described later.
The control device C is configured to receive information related to the power generated by the fuel cell 3 and information related to the amount of power stored in the power storage device 5.

  The fuel cell 3 as a power generation device supplies the power line 2 with generated power generated by following the load power required by the power line 2. The magnitude of the load power required on the power line 2 can be measured by the fourth power measuring means 9. The measurement result by the fourth power measuring means 9 is transmitted to the fuel cell 3, and the fuel cell 3 adjusts its own generated power with reference to the measurement result. The load power measured by the fourth power measuring means 9 is the sum of the total power consumption by the plurality of power consumption devices 4 and the total charge power by the plurality of power storage devices 5, and the total discharge power by the plurality of power storage devices 5. Subtracted value. As described above, the control device C can change the magnitude of the load power required on the power line 2 by discharging or charging the plurality of power storage devices 5 or not discharging or charging. it can. Since the generated power of the fuel cell 3 changes following the load power required by the power line 2, if the magnitude of the load power required by the power line 2 changes, the generated power of the fuel cell 3 follows the change. Change. Therefore, the control device C can indirectly change the generated power of the fuel cell 3 by instructing a plurality of power storage devices 5 to perform a charging operation and a discharging operation.

In the present embodiment, the discharge power of the first power storage device 5A is supplied only to the first power consumption device 4A. That is, the first power consuming device 4A is supplied with the power discharged from the first power storage device 5A within a range not exceeding the power consumption of the first power consuming device 4A and the external power system 1 through the power line 2. At least one of electric power and electric power supplied from the fuel cell 3 via the power line 2 is supplied.
Discharge power of second power storage device 5B is supplied only to second power consumption device 4B. That is, the second power consuming device 4B is supplied with the power discharged from the second power storage device 5B within a range not exceeding the power consumption of the second power consuming device 4B and the power line 2 from the external power system 1. At least one of electric power and electric power supplied from the fuel cell 3 via the power line 2 is supplied.

  As will be described below, when the total power consumption by the plurality of power consuming devices 4 is smaller than the set power for charging, the control device C has a plurality of power storage devices if the generated power of the fuel cell 3 is smaller than the set power for charging. When a command for charging operation is to be given to at least one of 5 and the total power consumption by the plurality of power consuming devices 4 is greater than the set power for discharge that is equal to or higher than the set power for charging, the power generation of the fuel cell 3 If the electric power is equal to or higher than the set electric power for discharge, it is configured to give an instruction for the discharge operation to at least one of the plurality of power storage devices 5. However, in the following description, the case where the set power for charging and the set power for discharge are the same value will be exemplified, and the value will be simply described as “set power”.

In the present embodiment, the control device C can cause the first power storage device 5A to perform a discharge operation and can cause the second power storage device 5B to perform a discharge operation. The electric power and the electric power discharged by the second power storage device 5B cannot be controlled. For example, when the control device C causes the first power storage device 5A to perform a discharging operation, the first power storage device 5A does not discharge only a part of the power corresponding to the power consumption of the first power consumption device 4A, One power storage device 5A discharges all of the power corresponding to the power consumption of the first power consuming device 4A. That is, when the power storage device 5 performs a discharging operation, the generated power of the fuel cell 3 may be lower than the set power. Therefore, in the present embodiment, the control device C is configured not to cause the power storage device 5 to perform a discharging operation when the power generation device 5 performs a discharging operation and the generated power of the fuel cell 3 falls below the set power.
Further, the control device C is configured to discharge the first power storage device 5A only when the second power storage device 5B is discharging. In other words, the first power storage device 5A is prevented from performing a discharging operation as much as possible, and a large amount of power stored in the first power storage device 5A is maintained.

  Next, with reference to FIG. 2 and FIG. 3, the timing at which each power storage device 5 is charged and discharged is described. 2 and 3 are flowcharts illustrating operation control performed by the control device C on the power storage device 5.

  As will be described in detail below, in the present embodiment, the control device C is configured to give priority to the charging operation command for the first power storage device 5A over the charging operation command for the second power storage device 5B. And the control which gives the command of discharge operation with respect to 2nd electrical storage apparatus 5B preferentially over the command of discharge operation with respect to 5 A of 1st electrical storage apparatuses is performed together.

In step # 100 of FIG. 2, the control device C determines whether or not the total power consumption by the plurality of power consumption devices 4 is smaller than the set power. In the present embodiment, the total power consumption by the plurality of power consumption devices 4 is the total power consumption measured by each of the first power measurement unit 6, the second power measurement unit 7, and the third power measurement unit 8. . In the present embodiment, the rated generated power of the fuel cell 3 is the “set power”. That is, when the total power consumption is smaller than the set power, that is, smaller than the rated power generation of the fuel cell 3, if there is no charge / discharge of each power storage device 5, the total power consumption of the plurality of power consumption devices 4 In order to cover this, it is necessary to operate the fuel cell 3 with less than the rated power generation. Then, when the total power consumption by the plurality of power consuming devices 4 is smaller than the set power (in the case of “Yes” in step # 100), the control device C proceeds to step # 102 and is equal to or greater than the set power. In the case ("No" in step # 100), the process proceeds to step # 116.
Hereinafter, the charging operation of each power storage device 5 will be described with reference to step # 102 to step # 114 shown in FIG. 2, and each power storage device 5 will be discharged with reference to step # 116 to step # 132 shown in FIG. The operation will be described.

[Charging operation]
In step # 102 of FIG. 2, the control device C determines whether or not the generated power of the fuel cell 3 is smaller than the set power. Further, in step # 112, the control device C determines whether or not the generated power of the fuel cell 3 is larger than the set power. That is, in step # 102 and step # 112, when the fuel cell 3 is operating with generated power smaller than the set power (shift to step # 104 described later), the generated power is greater than the set power. In the case where the fuel cell 3 is operating with the generated power equal to the set power, it is determined whether the fuel cell 3 is operating with the generated power equal to the set power. Hereinafter, each case will be described.

  In the present embodiment, the “set power” is set equal to the rated generated power of the fuel cell 3. Therefore, if the fuel cell 3 is operated with the generated power equal to the set power (that is, the rated generated power), there is an advantage that the power generation efficiency of the fuel cell 3 is increased. Therefore, the control device C performs control to operate the fuel cell 3 with generated power equal to the set power.

When the control device C determines in step # 102 that the fuel cell 3 is operating with generated power smaller than the set power, the control device C proceeds to step # 104. Here, in order to bring the generated power of the fuel cell 3 close to the set power, that is, in order to increase the generated power of the fuel cell 3 and approach the set power, it is necessary to increase the load power required by the power line 2. There is. Therefore, the control device C instructs the charging operation to at least one of the plurality of power storage devices 5 to increase the load power required by the power line 2.
That is, the control device C performs charging operation on at least one of the plurality of power storage devices 5 if the total power consumed by the plurality of power consuming devices 4 is smaller than the set power and the generated power of the fuel cell 3 is smaller than the set power. Is commanded.

  In step # 104, the control device C determines whether or not the amount of power stored in the first power storage device 5A is greater than or equal to the first set upper limit value, that is, whether or not the first power storage device 5A has a margin for a charging operation. judge. For example, the first set upper limit value can be set to the fully charged level of the first power storage device 5A. Control device C further performs charging operation when the amount of electricity stored in first power storage device 5A is not equal to or greater than the first set upper limit value, that is, because the amount of electricity stored in first power storage device 5A is smaller than the first set upper limit value. When there is a margin that can be done, the process proceeds to step # 106 to charge the first power storage device 5A. However, the control device C stops the charging operation when the amount of power stored in the first power storage device 5A reaches the first set upper limit value (for example, when the first power storage device 5A is fully charged).

When control device C determines in step # 104 that the amount of electricity stored in first power storage device 5A is equal to or greater than the first set upper limit value, control device C then proceeds to step # 108 and the amount of electricity stored in second power storage device 5B. Is greater than or equal to the second set upper limit value, that is, it is determined whether or not the second power storage device 5B has a margin for a charging operation. For example, the second set upper limit value can be set to the fully charged level of the second power storage device 5B. Then, the control device C further charges when the power storage amount of the second power storage device 5B is not greater than or equal to the second set upper limit value, that is, because the power storage amount of the second power storage device 5B is smaller than the second set upper limit value. When there is a margin for operation, the process proceeds to step # 110 to charge the second power storage device 5B. However, the control device C stops the charging operation when the amount of power stored in the second power storage device 5B reaches the second set upper limit value (for example, when the second power storage device 5B is fully charged).
As described above, in step # 106 and step # 110, the power generated by the fuel cell 3 can be charged using the first power storage device 5A and the second power storage device 5B. That is, surplus power of the fuel cell 3 can be charged by the first power storage device 5A and the second power storage device 5B.

  If the control device C determines in step # 112 that the fuel cell 3 is operating with generated power larger than the set power, that is, if the charging power in the plurality of power storage devices 5 is excessive, step # 114. Migrate to In step # 114, control device C stops the charging operation of power storage device 5 during the charging operation.

  Control device C determines in step # 112 that the generated power of fuel cell 3 is the set power and in step # 108 that the amount of power stored in second power storage device 5B is the second set upper limit value. In this case, the operation state of each power storage device 5 is maintained as it is.

  As described above, when the total power consumption by the plurality of power consuming devices 4 is smaller than the set power, the control device C is at least one of the plurality of power storage devices 5 if the generated power of the fuel cell 3 is smaller than the set power. An attempt is made to give a command for charging operation to the stand. That is, electric power derived from the fuel cell 3 is to be stored in the power storage device 5. Then, when the control device C tries to give a charging operation command to at least one of the plurality of power storage devices 5, the power storage amount of the first power storage device 5A is the first power storage device 5A. A command for a charging operation is given on condition that it is smaller than one set upper limit value, and for the second power storage device 5B, the amount of power stored in the first power storage device 5A is greater than or equal to the first set upper limit value and the second power storage device 5B. The charging operation command is given on the condition that the stored amount of electricity is smaller than the second set upper limit value. That is, when a command for charging operation is given to the first power storage device 5A, there is no restriction depending on the amount of power stored in the second power storage device 5B, but when a command for charging operation is given to the second power storage device 5B, Restriction is imposed by the amount of electricity stored in the device 5A. As a result, when a command for charging operation is to be given to the plurality of power storage devices 5, the command for charging operation is given to the first power storage device 5A in preference to the second power storage device 5B. Therefore, priority can be given to bringing the amount of power stored in the first power storage device 5A to the first set upper limit value or more.

[Discharge operation]
When the control device C determines in step # 100 shown in FIG. 2 that the total power consumption by the plurality of power consuming devices 4 is equal to or greater than the set power, the control device C proceeds to step # 116 shown in FIG. It is determined whether the generated power is smaller than the set power. Here, assuming that the generated power of the fuel cell 3 is set power, the received power from the external power system 1 (that is, as the total power consumed by the plurality of power consuming devices 4 becomes larger than the set power (ie, The power corresponding to the difference between the power generated by the fuel cell 3 and the total power consumed by the plurality of power consuming devices 4 is also increased. Therefore, when the total power consumption by the plurality of power consuming devices 4 is equal to or greater than the set power and the fuel cell 3 is operating with the generated power equal to or greater than the set power, the control device C starts from step # 116 shown in FIG. In step # 132, it is necessary to implement either a measure of reducing the generated power of the fuel cell 3 or a measure of reducing the received power from the external power system 1.

  When the control device C determines in step # 116 that the fuel cell 3 is operating with the generated power equal to or higher than the set power, the control device C proceeds to step # 118. And the control apparatus C reduces the generated electric power of the fuel cell 3 or reduces the received electric power from the external electric power grid | system 1 by carrying out discharge operation of the electrical storage apparatus 5 in each process of process # 120-process # 132. Let

Specifically, in step # 118, the control device C performs a discharge operation on whether or not the amount of power stored in the second power storage device 5B is equal to or lower than the second set lower limit value, that is, the power stored in the second power storage device 5B. Determine whether it is possible. For example, the second set lower limit value can be set to a level at which the amount of power stored in the second power storage device 5B is zero or another level greater than zero. If control device C determines in step # 118 that the amount of power stored in second power storage device 5B is greater than the second set lower limit value, that is, if second power storage device 5B is capable of discharging operation, control device C proceeds to step # 120. Then, it is further determined whether or not the second power storage device 5B is in a discharging operation.
On the other hand, control device C determines that the amount of power stored in second power storage device 5B is equal to or lower than the second set lower limit value in step # 118, that is, determines that second power storage device 5B cannot perform a discharging operation. In this case, the process returns to the beginning of the flowchart without causing the second power storage device 5B to perform the discharging operation. Further, in the present embodiment, since the first power storage device 5A is discharged only when the second power storage device 5B is performing the discharge operation, the control device C does not cause the second power storage device 5B to perform the discharge operation. In this case, the first power storage device 5A is not discharged.

  Next, when the control device C determines in step # 120 that the second power storage device 5B is not in a discharging operation, the control device C proceeds to step # 122 and the power consumption of the second power consumption device 4B is not zero. In addition, it is determined whether or not the generated power of the fuel cell 3 is less than the set power even when the second power storage device 5B is discharged. If the power consumption of the second power consumption device 4B is zero, the control device C does not need to discharge the second power storage device 5B. Further, when the second power storage device 5B performs the discharging operation, the control device C does not cause the second power storage device 5B to perform the discharging operation if the generated power of the fuel cell 3 falls below the set power. Accordingly, the control device C performs the process only when the power consumption of the second power consuming device 4B is not zero and the generated power of the fuel cell 3 does not fall below the set power even when the second power storage device 5B is discharged. The process proceeds to # 124.

  In step # 124, the control device C causes the second power storage device 5B to perform a discharging operation within a range equal to or lower than the upper limit discharge power (that is, the power consumption of the second power consumption device 4B). However, in the present embodiment, since the control device C cannot control the discharge power of the second power storage device 5B, the discharge power of the second power storage device 5B is substantially equal to the power consumption of the second power consumption device 4B. . However, the control device C has the second power storage device 5B when the power storage amount of the second power storage device 5B reaches the second set lower limit value, or when the power consumption of the second power consumption device 4B becomes zero, or If the generated power of the fuel cell 3 falls below the set power when the 5B is discharged, the discharging operation of the second power storage device 5B is stopped.

  If control device C determines in step # 120 that second power storage device 5B is in a discharging operation, control device C proceeds to step # 126, and the amount of power stored in first power storage device 5A becomes equal to or less than the first set lower limit value. It is determined whether or not the electric power stored in the first power storage device 5A can be discharged. When the amount of power stored in the first power storage device 5A is greater than the first set lower limit value, that is, when the first power storage device 5A is capable of discharging, the control device C proceeds to step # 128, The power storage device 5A is not discharged, the power consumption of the first power consumption device 4A is not zero, and even if the first power storage device 5A is discharged, the generated power of the fuel cell 3 falls below the set power. Only when there is not, the process proceeds to step # 130.

  In step # 130, the control device C causes the first power storage device 5A to perform a discharging operation within a range equal to or lower than the upper limit discharge power (that is, the power consumption of the first power consumption device 4A). However, in the present embodiment, since the control device C cannot control the discharge power of the first power storage device 5A, the discharge power of the first power storage device 5A is substantially equal to the power consumption of the second power consumption device 4B. . However, the control device C is configured such that when the power storage amount of the first power storage device 5A reaches the first set lower limit value, or when the power consumption of the first power consumption device 4A becomes zero, or the first power storage device If the generated power of the fuel cell 3 falls below the set power when the 5A is discharged, the discharging operation of the first power storage device 5A is stopped.

  If the control device C determines in step # 116 that the fuel cell 3 is operating with generated power smaller than the set power, the control device C proceeds to step # 132. That is, the reason why the fuel cell 3 is operated with the generated power smaller than the set power even though the total power consumption is equal to or higher than the set power is that the discharge power of any one of the power storage devices 5 is excessive. . Therefore, in step # 132, the control device C stops the discharging operation of the power storage device 5 during the discharging operation so that the generated power of the fuel cell 3 becomes equal to or higher than the set power. Note that, when both the first power storage device 5A and the second power storage device 5B are in the discharging operation, the control device C gives priority to stopping the discharging operation of the first power storage device 5A.

  As described above, when the total power consumption by the plurality of power consuming devices 4 is larger than the set power, the control device C can at least any of the plurality of power storage devices 5 if the generated power of the fuel cell 3 is equal to or greater than the set power. An attempt is made to give a discharge operation command to one unit. Then, when the control device C tries to give a discharge operation command to at least one of the plurality of power storage devices 5, the second power storage device 5B has a power storage amount of the second power storage device 5B. 2 It is not less than the set lower limit, the power consumption of the second power consuming device 4B is not zero, and the second power storage device 5B discharges the power corresponding to the power consumed by the second power consuming device 4B. Even if the generated power of the fuel cell 3 does not fall below the set power (set power for discharge), a discharge operation command is given, and the second power storage device 5B is in the discharge operation for the first power storage device 5A. The power storage amount of the first power storage device 5A is not less than or equal to the first set lower limit, the power consumption of the first power consumption device 4A is not zero, and the first power storage device 5A Corresponds to the power consumption of the first power consuming device 4A Giving an instruction of the discharge operation on condition that the generated power of the fuel cell 3 be discharged power does not fall below the set power (setting discharge power). That is, when giving a command for the discharge operation to the second power storage device 5B, there is no restriction depending on the state of the first power storage device 5A, but when giving a command for the discharge operation to the first power storage device 5A, It will be restricted by the state. As a result, when a command for discharging operation is to be given to the plurality of power storage devices 5, the command for discharging operation is given to the second power storage device 5B in preference to the first power storage device 5A. Accordingly, the amount of power stored in the second power storage device 5B decreases in preference to the amount of power stored in the first power storage device 5A, and as a result, a relatively large amount of power stored in the first power storage device 5A can be left. .

Next, an example of the operation of the power supply system according to the first embodiment will be described with reference to FIG. FIG. 4 is a diagram for explaining the relationship between the power consumption of the power consuming device 4, the charge / discharge operation of the power storage device 5, and the generated power of the fuel cell 3. In this example, the set power is 700 W. This value of 700 W is the rated generated power of the fuel cell 3.
In addition, what is shown with a broken line in FIG. 4 is a comparative example showing how the generated power of the fuel cell 3 changes when no power storage device is provided.

Hereinafter, first, an example in which the power storage device having the configuration of the present application is provided for each power consuming device will be described.
From time 0:00 to time 6:00, the total power consumption by the power consuming apparatus 4 is about 200 W, which is smaller than the set power (700 W). Therefore, the control device C first charges the first power storage device 5A (step # 106), and charges the second power storage device 5B after the power storage amount of the first power storage device 5A reaches the first set upper limit value. (Step # 110).
In this way, the load power required by the power line 2 can be increased by charging the first power storage device 5A and the second power storage device 5B, so that the power generated by the fuel cell 3 can be kept high. it can. On the other hand, when the power storage device is not provided, the load power required by the power line 2 cannot be increased. Therefore, as shown by the broken line in FIG. It must be operated with low power generation efficiency.

From time 6 o'clock to time 7 o'clock, the total power consumption by the power consuming device 4 is greater than 700 W. Therefore, the control device C causes the second power storage device 5B to perform a discharging operation (power corresponding to the power consumption of the second power consumption device 4B is discharged from the second power storage device 5B) (step # 124). In contrast, when the first power storage device 5A is discharged, that is, when the first power storage device 5A discharges power corresponding to the power consumption of the first power storage device 5A, the fuel cell 3 has left the third power remaining. The power consumption of the consuming device 4C is only covered by the generated power, and the generated power of the fuel cell 3 falls below the set power. Therefore, control device C does not discharge first power storage device 5A (“No” in step # 128).
The sum of the generated power of the fuel cell 3 and the discharged power of the second power storage device 5B is less than the total power consumed by the power consuming device 4, but the insufficient power is covered by the power supplied from the external power system 1. .

From time 7 o'clock to time 9 o'clock, the total power consumption by the power consuming device 4 is greater than 700W. However, since the power consumption of the second power consuming device 4B is zero, the control device C does not discharge the second power storage device 5B (“No” in step # 122). Further, since control device C does not perform discharge operation of second power storage device 5B, control device C also does not perform discharge operation of first power storage device 5A.
The power generated by the fuel cell 3 is less than the total power consumed by the power consuming device 4, but the insufficient power is covered by the power supplied from the external power system 1.

From time 9:00 to time 16:30, the total power consumption by the power consuming device 4 is in a state of less than 700W. Therefore, control device C performs a charging operation on either first power storage device 5A or second power storage device 5B if possible. In this example, since the amount of electricity stored in first power storage device 5A is equal to or greater than the first set upper limit value (determined as “Yes” in step # 104), control device C charges second power storage device 5B. Operate (step # 110).
In addition, when the amount of power stored in the second power storage device 5B becomes equal to or greater than the second set upper limit value (until “Yes” is determined in Step # 108), the control device C causes the second power storage device 5B to reach the time until 12:00. The charging operation is also stopped, and thereafter, no power storage device 5 is charged. As a result, from the time 12:00 to the time 16:30, the fuel cell 3 continues to operate in a state where the generated power is smaller than the set power (700 W).

  From 16:30 to 18:30, the total power consumption is greater than 700W. However, when the second power storage device 5B is discharged, the power generated by the fuel cell 3 falls below the set power. That is, if the second power storage device 5B is discharged to cover the power consumption of the second power consumption device 4B, the remaining power consumption of the first power consumption device 4A and the power consumption of the third power consumption device 4C Since the sum is smaller than the set power, the generated power of the fuel cell 3 is smaller than the set power. Therefore, control device C does not perform discharge operation of second power storage device 5B (“No” in step # 122). Accordingly, the control device C does not discharge the first power storage device 5A. As a result, the generated power (700 W) of the fuel cell 3 is less than the total power consumption of the power consuming device 4, but the insufficient power is covered by the power supplied from the external power system 1.

  From 18:30 to 22:30, the total power consumption is greater than 700W. Furthermore, even if the second power storage device 5B is discharged and the discharged power covers the power consumption of the second power consumption device 4B, the remaining power consumption of the first power consumption device 4A and the remaining power consumption of the third power consumption device 4C The total power consumption is equal to or greater than the set power, and the power generated by the fuel cell 3 is equal to or greater than the set power. Therefore, the control device C causes the second power storage device 5B to perform a discharging operation (step # 124). When the first power storage device 5A is discharged from the time 18:30 to the time 20:00 and from the time 21:00 to the time 22:30 and the power consumption of the first power consumption device 4A is covered by the discharged power, The power consumption of the remaining third power consuming device 4C is smaller than the set power. Therefore, the control device C does not perform the discharging operation of the first power storage device 5A in order to prevent the generated power of the fuel cell 3 from falling below the set power (“No” in step # 128). Note that, even if the first power storage device 5A is discharged from time 20:00 to time 21:00, the generated power of the fuel cell 3 is equal to or higher than the set power, so the control device C causes the first power storage device 5A to discharge. (Step # 130).

  From 22:30 to 24:00, the total power consumption is greater than 700W. However, when the second power storage device 5B is discharged, the power generated by the fuel cell 3 falls below the set power. Therefore, the control device C does not discharge the second power storage device 5B (“No” in step # 122). Accordingly, the control device C does not discharge the first power storage device 5A. As a result, the generated power (700 W) of the fuel cell 3 is less than the total power consumption of the power consuming device 4, but the insufficient power is covered by the power supplied from the external power system 1.

  On the other hand, in the comparative example indicated by a broken line in FIG. 3 where the power storage device 5 is not provided at all, the time zone during which the fuel cell 3 is reduced to less than the rated generated power increases significantly. As a result, it can be said that the fuel cell 3 is not efficiently operated as compared with the present application.

Second Embodiment
The power supply system of the second embodiment is different from the first embodiment in the method of operation control of the power storage device 5 by the control device C. The power supply system of the second embodiment will be described below, but the description of the same configuration as that of the first embodiment will be omitted.

In the present embodiment, the control device C can cause the first power storage device 5A to perform a discharge operation and can cause the second power storage device 5B to perform a discharge operation. Adjusting the magnitude of the discharge power regardless of the magnitude of the power consumption of the first power consuming device 4A and causing the second power storage device 5B to change the magnitude of the discharge power to the second power consumption. The discharge operation can be performed with adjustment regardless of the power consumption of the device 4B.
Further, the control device C is configured to cause only the first power storage device 5A to be discharged, although the second power storage device 5B is preferentially discharged.

  With reference to FIGS. 5 and 6, the timing at which the first power storage device 5A and the second power storage device 5B are charged and discharged will be described. 5 and 6 are flowcharts illustrating operation control performed by the control device C on the power storage device 5.

In step # 200 of FIG. 5, the control device C determines whether or not the total power consumption by the plurality of power consumption devices 4 is smaller than the set power. Also in this embodiment, the rated generated power of the fuel cell 3 is set as the “set power”. Then, when the total power consumed by the plurality of power consuming devices 4 is smaller than the set power (in the case of “Yes” in step # 200), the control device C proceeds to step # 202 and is equal to or greater than the set power. In the case ("No" in step # 200), the process proceeds to step # 216.
Hereinafter, the charging operation of each power storage device 5 will be described with reference to step # 202 to step # 214 shown in FIG. 5, and the discharge of each power storage device 5 will be described with reference to step # 216 to step # 230 shown in FIG. The operation will be described.

[Charging operation]
In step # 202 of FIG. 5, the control device C determines whether or not the generated power of the fuel cell 3 is smaller than the set power. Further, in step # 212, the control device C determines whether or not the generated power of the fuel cell 3 is larger than the set power. That is, in step # 202 and step # 212, when the fuel cell 3 is operating with generated power smaller than the set power (shift to step # 204 described later), the generated power is greater than the set power. In the case where the fuel cell 3 is operating with the generated power equal to the set power, it is determined whether the fuel cell 3 is operating with the generated power equal to the set power. Hereinafter, each case will be described.

  Also in the present embodiment, the “set power” is set equal to the rated generated power of the fuel cell 3. Therefore, if the fuel cell 3 is operated with the generated power equal to the set power (that is, the rated generated power), there is an advantage that the power generation efficiency of the fuel cell 3 is increased. Therefore, the control device C performs control to operate the fuel cell 3 with generated power equal to the set power.

If the control device C determines in step # 202 that the fuel cell 3 is operating with generated power smaller than the set power, the control device C proceeds to step # 204. Here, in order to bring the generated power of the fuel cell 3 close to the set power, that is, in order to increase the generated power of the fuel cell 3 and approach the set power, it is necessary to increase the load power required by the power line 2. There is. Therefore, the control device C instructs the charging operation to at least one of the plurality of power storage devices 5 to increase the load power required by the power line 2.
That is, the control device C performs charging operation on at least one of the plurality of power storage devices 5 if the total power consumed by the plurality of power consuming devices 4 is smaller than the set power and the generated power of the fuel cell 3 is smaller than the set power. Is commanded.

  In step # 204, the control device C determines whether or not the amount of power stored in the first power storage device 5A is greater than or equal to the first set upper limit value, that is, whether or not the first power storage device 5A has a margin for a charging operation. judge. For example, the first set upper limit value can be set to the fully charged level of the first power storage device 5A. Control device C further performs charging operation when the amount of electricity stored in first power storage device 5A is not equal to or greater than the first set upper limit value, that is, because the amount of electricity stored in first power storage device 5A is smaller than the first set upper limit value. When there is a margin that can be done, the process proceeds to step # 206 to charge the first power storage device 5A. However, the control device C stops the charging operation when the amount of power stored in the first power storage device 5A reaches the first set upper limit value (for example, when the first power storage device 5A is fully charged).

If control device C determines in step # 204 that the amount of electricity stored in first power storage device 5A is greater than or equal to the first set upper limit value, control device C then proceeds to step # 208 and the amount of electricity stored in second power storage device 5B. Is greater than or equal to the second set upper limit value, that is, it is determined whether or not the second power storage device 5B has a margin for a charging operation. For example, the second set upper limit value can be set to the fully charged level of the second power storage device 5B. Then, the control device C further charges when the power storage amount of the second power storage device 5B is not greater than or equal to the second set upper limit value, that is, because the power storage amount of the second power storage device 5B is smaller than the second set upper limit value. When there is room for operation, the process proceeds to step # 210, and the second power storage device 5B is charged. However, the control device C stops the charging operation when the amount of power stored in the second power storage device 5B reaches the second set upper limit value (for example, when the second power storage device 5B is fully charged).
As described above, in step # 206 and step # 210, the power generated by the fuel cell 3 can be charged using the first power storage device 5A and the second power storage device 5B. That is, surplus power of the fuel cell 3 can be charged by the first power storage device 5A and the second power storage device 5B.

  If the control device C determines in step # 212 that the fuel cell 3 is operating with generated power larger than the set power, that is, if the charging power in the plurality of power storage devices 5 is excessive, step # 214. Migrate to In step # 214, the control device C reduces the charging power of the power storage device 5 during the charging operation so that the generated power of the fuel cell 3 becomes the set power.

  Control device C determines in step # 212 that the generated power of fuel cell 3 is the set power in step # 212 and in step # 208 that the amount of power stored in second power storage device 5B is the second set upper limit value. In this case, the operation state of each power storage device 5 is maintained as it is.

[Discharge operation]
When the control device C determines in step # 200 shown in FIG. 5 that the total power consumption by the plurality of power consuming devices 4 is equal to or greater than the set power, the control device C proceeds to step # 216 shown in FIG. It is determined whether the generated power is smaller than the set power.

  When the control device C determines in step # 216 that the fuel cell 3 is operating with the generated power equal to or higher than the set power, the control device C proceeds to step # 218. Then, control device C causes power storage device 5 to perform a discharging operation in each of steps # 220 to # 230.

  Specifically, in step # 218, the control device C discharges whether or not the amount of power stored in the second power storage device 5B is equal to or lower than the second set lower limit value, that is, the power stored in the second power storage device 5B. Determine whether it is possible. For example, the second set lower limit value can be set to a level at which the amount of power stored in the second power storage device 5B is zero or another level greater than zero. If control device C determines in step # 118 that the amount of power stored in second power storage device 5B is greater than the second set lower limit value, that is, if second power storage device 5B is capable of discharging, it proceeds to step # 220. Thus, the upper limit discharge power (that is, the second power consumption device 4B) is set so that the power consumption of the second power consumption device 4B is not zero and the second power storage device 5B has the generated power of the fuel cell 3 equal to or higher than the set power. It is determined whether or not the discharge operation is in the following range.

  That is, if the power consumption of the second power consuming device 4B is zero, the control device C does not need to discharge the second power storage device 5B. Next, whether or not to discharge the first power storage device 5A is determined. The process proceeds to step # 224. Further, even if the second power storage device 5B is already in a discharging operation, the process proceeds to a determination (step # 224) as to whether or not the first power storage device 5A is to be discharged. And the control apparatus C is the range below the upper limit discharge power so that the power consumption of the 2nd power consumption apparatus 4B is not zero, and the 2nd electrical storage apparatus 5B makes the electric power generation of the fuel cell 3 more than setting electric power. Only when the discharging operation is not being performed, the process proceeds to step # 222. In step # 222, the control device C discharges the second power storage device 5B with the upper limit discharge power (that is, the power consumption of the second power consumption device 4B). However, when the amount of power stored in the second power storage device 5B reaches the second set lower limit value, or when the power consumption of the second power consumption device 4B becomes zero, the control device C determines that the second power storage device The discharging operation of 5B is stopped.

  If control device C determines in step # 218 that the amount of power stored in second power storage device 5B is equal to or less than the second set lower limit value, that is, if it is determined that second power storage device 5B cannot perform the discharging operation, control device C224 Migrate to That is, in the present embodiment, since the first power storage device 5A can be discharged even if the second power storage device 5B is not performing the discharge operation, the control device C can store the amount of power stored in the second power storage device 5B. Is less than or equal to the second set lower limit value (that is, even if the second power storage device 5B cannot perform the discharging operation), the process proceeds to step # 224 to determine whether or not to discharge the first power storage device 5A. Do.

  In step # 224, control device C determines whether or not the amount of power stored in first power storage device 5A is equal to or lower than the first set lower limit value, that is, whether the power stored in first power storage device 5A can be discharged. Determine whether or not. Then, when the amount of electricity stored in the first power storage device 5A is larger than the first set lower limit value, that is, when the first power storage device 5A is capable of discharging, the control device C proceeds to step # 226, The upper limit discharge power (that is, the power consumption of the first power consumption device 4A) is set so that the power consumption of the power consumption device 4A is not zero and the power generation power of the fuel cell 3 is equal to or higher than the set power in the first power storage device 5A. It is determined whether or not the discharging operation is in the following range. That is, if the power consumption of the first power consuming device 4A is zero, the control device C does not have to discharge the first power storage device 5A. Further, if the first power storage device 5A is already in the discharging operation, there is no need to newly operate the first power storage device 5A. Then, the control device C has a power consumption of the first power consuming device 4A that is not zero, and the first power storage device 5A is within a range that is less than or equal to the upper limit discharge power so that the power generated by the fuel cell 3 is greater than or equal to the set power. Only when the discharging operation is not being performed, the process proceeds to step # 228. Then, in step # 228, the control device C causes the first power storage device 5A to perform a discharge operation within a range equal to or lower than the upper limit discharge power so that the generated power of the fuel cell 3 becomes the set power. However, when the amount of electricity stored in the first power storage device 5A reaches the first set lower limit value or when the power consumption of the first power consumption device 4A becomes zero, the control device C determines that the first power storage device 5A The 5A discharge operation is stopped.

  When it is determined in step # 216 that the fuel cell 3 is operating with the generated power smaller than the set power, the control device C proceeds to step # 230. That is, the reason why the fuel cell 3 is operated with the generated power smaller than the set power even though the total power consumption is equal to or higher than the set power is that the discharge power of any one of the power storage devices 5 is excessive. . Therefore, in step # 230, the control device C reduces the discharge operation of the power storage device 5 during the discharge operation so that the generated power of the fuel cell 3 is equal to or higher than the set power. Note that when both the first power storage device 5A and the second power storage device 5B are in a discharging operation, the control device C gives priority to the reduction of the discharge power of the first power storage device 5A.

  As described above, when the control device C attempts to give a discharge operation command to at least one of the plurality of power storage devices 5, the power storage of the second power storage device 5B is given to the second power storage device 5B. The generated power of the fuel cell 3 becomes set power (set power for discharge) on condition that the amount is not less than or equal to the second set lower limit value and the power consumption of the second power consuming device 4B is not zero. To the first power storage device 5A, the amount of power stored in the second power storage device 5B is zero, or the second power consumption device 4B is discharged. The condition is that the power storage device 5B is in a discharging operation, the power storage amount of the first power storage device 5A is not less than or equal to the first set lower limit value, and the power consumption of the first power consumption device 4A is not zero. The generated power of the fuel cell 3 is set power (for discharge Giving an instruction of the discharge operation of the discharge power of the constant power) and so as to power the range of the first power device 4A. That is, when giving a command for the discharge operation to the second power storage device 5B, there is no restriction depending on the state of the first power storage device 5A, but when giving a command for the discharge operation to the first power storage device 5A, It will be restricted by the state. As a result, when a command for discharging operation is to be given to the plurality of power storage devices 5, the command for discharging operation is given to the second power storage device 5B in preference to the first power storage device 5A. Accordingly, the amount of power stored in the second power storage device 5B decreases in preference to the amount of power stored in the first power storage device 5A, and as a result, a relatively large amount of power stored in the first power storage device 5A can be left. .

Next, an example of the operation of the power supply system according to the second embodiment will be described with reference to FIG. In this example, the set power is 700 W. FIG. 7 is a diagram for explaining the relationship between the power consumption of the power consuming device 4, the charge / discharge operation of the power storage device 5, and the generated power of the fuel cell 3. In this example, the set power is 700 W. This value of 700 W is the rated generated power of the fuel cell 3.
In addition, what is shown with a broken line in FIG. 7 is a comparative example showing how the generated power of the fuel cell 3 changes when no power storage device is provided.

Hereinafter, first, an example in which the power storage device having the configuration of the present application is provided for each power consuming device will be described.
From time 0:00 to time 6:00, the total power consumption by the power consuming apparatus 4 is about 200 W, which is smaller than the set power (700 W). Therefore, the control device C first charges the first power storage device 5A (step # 206), and charges the second power storage device 5B after the power storage amount of the first power storage device 5A reaches the first set upper limit value. (Step # 210).
In this way, the load power required by the power line 2 can be increased by charging the first power storage device 5A and the second power storage device 5B, so that the power generated by the fuel cell 3 can be kept high. it can. On the other hand, when the power storage device is not provided, the load power required by the power line 2 cannot be increased. Therefore, as shown by the broken line in FIG. It must be operated with low power generation efficiency.

  From time 6 o'clock to time 7 o'clock, the total power consumption by the power consuming device 4 is greater than 700 W. Therefore, the control device C causes the second power storage device 5B to perform a discharging operation. At this time, the control device C has a discharge power of the second power storage device 5B within a range equal to or less than the upper limit discharge power (that is, the power consumption of the second power consumption device 4B) so that the generated power of the fuel cell 3 is equal to or higher than the set power. Is controlled (step # 222). Even if all of the power consumption of the second power consumption device 4B is covered by the discharge power of the second power storage device 5B, the sum of the power consumption of the first power consumption device 4A and the power consumption of the third power consumption device 4C is , 700 W (ie, “No” is determined in Step # 200). Therefore, the control device C reduces the discharge power of the first power storage device 5A within a range equal to or lower than the upper limit discharge power (that is, power consumption of the first power consumption device 4A) so that the generated power of the fuel cell 3 becomes equal to or higher than the set power. Control (step # 228). In this case, the discharge power of the first power storage device 5A is derived by subtracting the generated power (700 W) of the fuel cell 3 and the discharge power of the second power storage device 5B from the total power consumption by the power consumption device 4 ( However, the power consumption is equal to or lower than the power consumption of the first power consuming device 4A.

  From time 7 o'clock to time 9 o'clock, the total power consumption by the power consuming device 4 is greater than 700W. However, since the power consumption of the second power consumption device 4B is zero, the control device C does not cause the second power storage device 5B to perform a discharging operation (“No” in step # 220). Therefore, the control device C reduces the discharge power of the first power storage device 5A within a range equal to or lower than the upper limit discharge power (that is, power consumption of the first power consumption device 4A) so that the generated power of the fuel cell 3 becomes equal to or higher than the set power. Control (step # 228).

From time 9:00 to time 16:30, the total power consumption by the power consuming device 4 is in a state of less than 700W. Therefore, control device C performs a charging operation on either first power storage device 5A or second power storage device 5B if possible. In this example, control device C preferentially performs the charging operation of first power storage device 5A from time 9:00 to time 11:30 (step # 206), and the amount of power stored in first power storage device 5A is the first. When the value is equal to or higher than the one set upper limit value, the second power storage device 5B is then charged (step # 210).
In addition, when the amount of power stored in the second power storage device 5B becomes equal to or greater than the second set upper limit value (until “Yes” is determined in Step # 208), the control device C causes the second power storage device 5B to reach the time until 14:00. The charging operation is also stopped, and thereafter, no power storage device 5 is charged. As a result, from 14:00 to 16:30, the fuel cell 3 continues to operate in a state where the generated power is smaller than the set power (700 W).

From 16:30 to 24:00, the total power consumption is greater than 700W. The control device C controls the discharge power of the second power storage device 5B within a range equal to or lower than the upper limit discharge power (that is, power consumption of the second power consumption device 4B) so that the generated power of the fuel cell 3 becomes equal to or higher than the set power. (Step # 222).
Furthermore, even if the entire power consumption of the second power consuming device 4B is covered by the discharged power of the second power storage device 5B between the time 18:30 and the time 22:30, the power consumption of the first power consuming device 4A The total power consumption of the third power consuming apparatus 4C is greater than 700 W (ie, “No” is determined in Step # 200). Therefore, the control device C reduces the discharge power of the first power storage device 5A within a range equal to or lower than the upper limit discharge power (that is, power consumption of the first power consumption device 4A) so that the generated power of the fuel cell 3 becomes equal to or higher than the set power. Control (step # 228).

  On the other hand, in the comparative example indicated by a broken line in FIG. 3 where the power storage device 5 is not provided at all, the time zone during which the fuel cell 3 is reduced to less than the rated generated power increases significantly. As a result, it can be said that the fuel cell 3 is not efficiently operated as compared with the present application.

<Another embodiment>
<1>
In the above embodiment, the configuration of the power supply system may be changed as appropriate. For example, although a fuel cell has been described as an example of a power generation device, other types of devices such as a power generation device including an engine and a generator driven by the engine may be used.
Moreover, although the case where the set power is the rated generated power of the power generation apparatus (fuel cell 3) is illustrated in the above embodiment, other power values other than the rated generated power may be set as the set power. The set power may be a fixed value or a variable value. For example, when a solar power generation device is used as the power generation device of the present invention, the rated generated power of the solar power generation device is a variable value. Therefore, when the rated generated power of the photovoltaic power generator is adopted as the set power, the set power becomes a fluctuation value.
Furthermore, in the above-described embodiment, the example in which the power consuming device 4 is classified into three types has been described. However, the power consuming device 4 is classified into at least two types, and each of the power consuming devices 4 is the first power storage device 5A or the second power storage device 5B. What is necessary is just to comprise so that it may be connected to.

<2>
In the above embodiment, referring to the flowcharts shown in FIGS. 2, 3, 5, and 6, control device C issues a command for charging operation to first power storage device 5 </ b> A to charge operation for second power storage device 5 </ b> B. An example of performing both the control to give priority over the command and the control to give the command for the discharge operation to the second power storage device 5B in preference to the command for the discharge operation to the first power storage device 5A. As described above, the control for giving the charge operation command to the first power storage device 5A in preference to the charge operation command to the second power storage device 5B, and the discharge operation command to the second power storage device 5B. It is also possible to perform any one of the controls to be given with priority over the discharge operation command for one power storage device 5A.

<3>
In the above embodiment, the set upper limit value and the set lower limit value of the storage amount of each power storage device 5 can be set as appropriate. For example, when it is intended to ensure sufficient charge margin and discharge margin sufficient to cope with an emergency, the set upper limit value of the power storage amount of the power storage device 5 may be set lower than the full charge level. The set lower limit value of the power storage amount of the power storage device 5 may be set higher than the level at which the power storage amount is zero. Further, the first power storage device 5A and the second power storage device 5B may have the same capacity, or may have different capacities. Furthermore, the set upper limit value and the set lower limit value of the charged amount of the first power storage device 5A and the charged amount of the second power storage device 5B can be set separately.

<4>
In the above embodiment, the example in which the power supply system includes one group including the first power consuming device 4A and the first power storage device 5A has been described. However, the first power consuming device 4A and the first power storage device 5A are provided. A plurality of groups may be provided. That is, in the power supply system, at least one first power consuming device 4A among the plurality of power consuming devices 4 is connected to one or two or more first power stor- age devices 5A among the plurality of power storing devices 5. Can be adopted.
Similarly, in the above-described embodiment, the example in which the power supply system includes one group including the second power consuming device 4B and the second power storage device 5B has been described. However, the second power consuming device 4B and the second power storage device have been described. A plurality of groups including the device 5B may be provided. In other words, in the power supply system, at least one second power consuming device 4B among the plurality of power consuming devices 4 with respect to the other one or two or more second power stor- age devices 5B among the plurality of power storing devices 5. Can be adopted.

<5>
In the above embodiment, an example in which one or more devices among the plurality of power storage devices 5 are the first power storage device 5A and the other one or more devices are the second power storage devices 5B has been described. Alternatively, whether each of the plurality of power storage devices 5 is the first power storage device 5A or the second power storage device 5B may be dynamically changed. For example, the control device C changes the level of importance of each of the plurality of power consuming devices 4 in accordance with a predetermined importance level determination rule, and accordingly changes the level of importance of each of the plurality of power storage devices 5. May be. That is, the device set as the first power consuming device 4A and the device connected to the first power consuming device 5A and set as the first power consuming device 5A are changed in setting as the second power consuming device 4B and set as the second power consuming device 5B. There are also cases where it is changed or vice versa. Thus, each of the plurality of power storage devices 5 is distinguished according to the level of importance of the connected power consuming device 4 (that is, whether it is the first power storage device 5A or the second power storage device 5B). If the importance level of the power consuming device 4 is changed, the importance level of the power storage device 5 connected thereto is also changed.
An example of the importance determination rule includes changing the importance of each power consuming device 4 according to the time zone. For example, for a certain power consumption device 4, the importance is set high in a specific time zone (that is, set as the first power consumption device 4A), and the importance is set low in other time zones (ie, An importance determination rule such as “set as the second power consuming device 4B” can be given as an example. Note that this importance determination rule is given as an example, and other importance determination rules may be adopted.

<6>
In the above-described embodiment, an example in which the setting power for charging and the setting power for discharging have the same value has been described. However, the setting power for discharging may be equal to or higher than the setting power for charging. For example, the discharge setting power may be set to a value different from the charging setting power, specifically, a value larger than the charging setting power.

  INDUSTRIAL APPLICABILITY The present invention can be used in a power supply system that can secure more power that can be used by a specific power consuming device than power that can be used by other power consuming devices.

1 External power system 2 Power line 2A Power line 2B Power line 2C Power line 3 Fuel cell (power generation device)
4 power consuming device 4A first power consuming device 4B second power consuming device 4C third power consuming device 5 power storage device 5A first power storage device 5B second power storage device 6 first power measuring means 7 second power measuring means 8 third Power measuring means 9 Fourth power measuring means C Controller

Claims (5)

A power line connected to an external power system, a power generation device capable of supplying generated power to the power line, a plurality of power storage devices connected to the power line separately, and a control for controlling operations of the plurality of power storage devices A power supply system capable of supplying a plurality of power consuming devices with power supplied from at least one of the external power system, the power generation device, and the power storage device,
At least one first power consuming device of the plurality of power consuming devices is connected to one or two or more first power stor- age devices among the plurality of power storing devices,
The other one or two or more second power storage devices in the plurality of power storage devices are connected to at least one second power consumption device in the plurality of power consumption devices,
The first power consuming device includes power discharged from the first power storage device within a range not exceeding power consumption of the first power consuming device, and power supplied from the external power system via the power line. , At least one of the power supplied from the power generation device via the power line is supplied,
The second power consuming device includes power discharged from the second power storage device within a range not exceeding power consumption of the second power consuming device, and power supplied from the external power system via the power line. , At least one of the power supplied from the power generation device via the power line is supplied,
The control device is configured to give a command to give a charge operation command to the first power storage device in preference to a charge operation command to the second power storage device, and a discharge operation command to the second power storage device. An electric power supply system that performs at least one of control to be given with priority over a discharge operation command to the first power storage device. The power generation device supplies the power line with generated power generated by following the load power required on the power line,
The control device includes:
When the total power consumed by the plurality of power consuming devices is smaller than the set power for charging, if the generated power of the power generating device is smaller than the set power for charging, at least one of the plurality of power storage devices is charged. Trying to give a directive,
When the total power consumption by the plurality of power consuming devices is greater than the set power for discharge that is equal to or greater than the set power for charging, and the generated power of the power generator is equal to or greater than the set power for discharge, the plurality of power storages The power supply system according to claim 1, wherein a command for discharging operation is given to at least one of the devices. When the control device tries to give a command for charging operation to at least one of the plurality of power storage devices,
For the first power storage device, a charge operation command is given on the condition that the power storage amount of the first power storage device is smaller than a first set upper limit value,
The second power storage device is charged on condition that the power storage amount of the first power storage device is not less than the first set upper limit value and the power storage amount of the second power storage device is smaller than the second set upper limit value. The power supply system according to claim 2 which gives a command of operation. The first power storage device is configured to discharge power corresponding to power consumption of the first power consuming device when a discharge operation command is given,
The second power storage device is configured to discharge power corresponding to the power consumption of the second power consuming device when a discharge operation command is given,
When the control device tries to give a discharge operation command to at least one of the plurality of power storage devices,
For the second power storage device, the power storage amount of the second power storage device is not less than or equal to a second set lower limit value, the power consumption of the second power consumption device is not zero, and the second power storage device 2 Even when the power storage device discharges power corresponding to the power consumption of the second power consuming device, a command for a discharge operation is provided on the condition that the generated power of the power generating device does not fall below the set power for discharge,
For the first power storage device, the second power storage device is in a discharging operation, the power storage amount of the first power storage device is not less than a first set lower limit value, and the first power Even if the power consumption of the consuming device is not zero, and even if the first power storage device discharges power corresponding to the power consumed by the first power consuming device, the generated power of the power generating device is equal to the set power for discharge. The power supply system according to claim 2 or 3, wherein a command for a discharge operation is given on condition that the value is not lower. The first power storage device is configured to be able to perform a discharge operation by adjusting the magnitude of discharge power regardless of the power consumption of the first power consuming device,
The second power storage device is configured to be able to perform a discharge operation by adjusting the magnitude of discharge power regardless of the magnitude of power consumption of the second power consuming device,
When the control device tries to give a discharge operation command to at least one of the plurality of power storage devices,
For the second power storage device, the power storage amount of the second power storage device is not less than or equal to a second set lower limit value, and the power consumption of the second power consumption device is not zero. Giving a command for a discharge operation with a discharge power in a range equal to or lower than the power consumption of the second power consuming device so that the generated power of the power generating device becomes the set power for discharge;
For the first power storage device, the power storage amount of the second power storage device is zero or the second power storage device is in a discharging operation, and the power storage amount of the first power storage device is a first setting. On the condition that the power consumption of the first power consuming device is not zero or less and the power consumption of the first power consuming device is such that the generated power of the power generating device becomes the set power for discharge. The power supply system according to claim 2 or 3, wherein a command for a discharge operation with discharge power in a range equal to or lower than power consumption is given.

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