JP2011075443A - Power distribution system and method of calculating residual capacity of storage battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect the residual capacity of a storage battery, regardless of the presence of deterioration in a power distribution system and a method of calculating the residual capacity of a storage battery. <P>SOLUTION: A storage battery is deteriorated by repeated charges and discharges of electronic power. The deteriorated storage battery becomes fully charged capacity smaller as compared with a new one. In the present invention, fully charged capacities of storage batteries 61 and 62 are set accurately, based on the deterioration rates of the storage batteries 61 and 62. Thus, even when the storage batteries 61 and 62 deteriorate, their residual capacities can be detected accurately abased on SOC (residual capacity), referring to accurate fully charged residual capacity as a reference. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power distribution system that supplies electric power from a storage battery to various loads, and a storage battery remaining capacity calculation method that calculates the capacity of the storage battery.

  Conventionally, SOC (State Of Charge) is known as an index indicating the remaining rate of a storage battery. The SOC is represented by a numerical value of 0 to 100%. When the SOC is 100%, the storage battery is fully charged, and when the SOC is 0%, the remaining capacity of the storage battery is zero. The SOC can be calculated by comparing the reference voltage and the battery voltage Vb at the time of measurement, with the battery voltage in the fully charged state as the reference voltage. Moreover, it is also possible to calculate the SOC by integrating the current (charge / discharge current) values flowing into and out of the storage battery (see, for example, Patent Document 1).

JP 2005-37230 A

  By the way, the said storage battery deteriorates by repeating charging / discharging. As the storage battery deteriorates, the full charge capacity of the storage battery decreases. For example, it is assumed that the full charge capacity of a new storage battery is 100 Wh, whereas the full charge capacity of the storage battery is reduced by 20 Wh due to deterioration, and the full charge capacity is 80 Wh. Here, even when the storage battery is deteriorated, for example, the fully charged battery voltage Vb does not change. Accordingly, the battery voltages Vb of the new and deteriorated storage batteries in the fully charged state are equal, and the SOCs of both storage batteries are 100%. Thus, even if the SOC is 100%, the remaining capacities of both storage batteries are different. Therefore, even if the SOC is 100%, for example, a new storage battery has an amount of power for operating a 100 W electronic device for 1 hour, but a deteriorated storage battery has a power for operating a 100 W electronic device for 48 minutes. Has only quantity. Thus, in a deteriorated storage battery, it has been difficult to calculate an accurate remaining capacity (power storage amount) from the SOC.

  The present invention has been made in view of such circumstances, and an object thereof is to calculate an accurate remaining capacity of a storage battery regardless of the presence or absence of deterioration.

Hereinafter, means for achieving the above-described object and its operation and effects will be described.
The invention according to claim 1 is a storage battery connected to an electric load so as to be able to supply power, a remaining rate calculating means for calculating a remaining rate of the storage battery, and a deterioration rate calculating means for calculating a deterioration rate of the storage battery. And setting the full charge capacity of the storage battery based on the deterioration rate of the storage battery calculated by the deterioration rate calculating means for each predetermined period, and from the remaining capacity rate of the storage battery based on the full charge capacity The gist is to include a control unit for calculating the remaining capacity.

  In general, a storage battery deteriorates due to repeated charging and discharging of electric power. A storage battery that has deteriorated has a smaller full charge capacity than a new storage battery. According to the said structure, the exact full charge capacity of the battery is set based on the deterioration rate of a storage battery. Thereby, even when the storage battery is deteriorated, the remaining capacity can be calculated with higher accuracy based on the remaining capacity rate based on the accurate full charge capacity.

  The invention according to claim 2 is provided with a plurality of the storage batteries, and includes a battery voltage detecting means for detecting a voltage of each of the storage batteries, and the control unit is configured to charge and discharge at least one of the plurality of storage batteries. Set to a consumption mode storage battery to be used, out of the plurality of storage batteries, excluding the consumption mode storage battery, at least one is set to a reference mode used for calculating the deterioration rate of the consumption mode storage battery, The deterioration rate calculating means is based on a comparison of the time required for stepping up or stepping down a predetermined voltage width of the reference mode storage battery and the consumption mode storage battery detected by the battery voltage detection means. The control unit sets a full charge capacity of the storage battery in the consumption mode based on the calculated deterioration rate of the storage battery in the consumption mode, and based on the full charge capacity. And as its gist to calculate the remaining capacity of the storage battery of the consumption mode from the remaining rate as.

  As described above, although the full charge capacity of the deteriorated storage battery is small, the battery voltage value becomes the same as that of a new storage battery at the time of full charge. Therefore, a storage battery that has been deteriorated has a faster voltage drop rate with respect to a predetermined discharge amount during discharge and a faster voltage increase rate with respect to a predetermined charge amount during charging than a new storage battery.

  According to the above configuration, the deterioration rate of the storage battery in the consumption mode is calculated by comparing the time required for raising and lowering the predetermined voltage width of the storage battery set in the consumption mode and the reference mode. The control unit sets the full charge capacity of the battery based on the deterioration rate of the storage battery in the consumption mode. Thereby, even when the storage battery in the consumption mode is deteriorated, the remaining capacity can be calculated with higher accuracy based on the remaining capacity rate based on the accurate full charge capacity.

  According to a third aspect of the present invention, in the power distribution system according to the second aspect, the control unit sets the full charge capacity of the storage battery in the consumption mode, and then sets the storage battery in the consumption mode to the reference mode. The gist is to switch the mode storage battery to the consumption mode.

  According to this configuration, the storage battery in the reference mode and the consumption mode is switched after setting the full charge capacity of the storage battery in the consumption mode. Here, the consumption mode storage battery in which charging and discharging are repeated is more likely to deteriorate than the reference mode storage battery. In that respect, according to the present invention, the storage battery in the consumption mode in which charging / discharging is repeated every predetermined period is switched to the reference mode, so that deterioration of the storage battery can be suppressed and the life of the storage battery can be extended.

The gist of the invention according to claim 4 is that, in the power distribution system according to claim 2 or 3, the storage battery in the reference mode is used as an emergency power source.
According to this configuration, the reference mode storage battery is used as an emergency power source. Therefore, even if power supply from the storage battery in the consumption mode and other power systems is disabled, power supply from the storage battery in the reference mode to the load is possible.

  The gist of the invention according to claim 5 is that, in the power distribution system according to claim 2, the storage battery in the reference mode is a storage battery having a smaller full charge capacity than the storage battery in the consumption mode.

  According to this configuration, since the full charge capacity of the reference mode storage battery is small, the power distribution system can be configured more compactly. Further, even when the full charge capacities of the storage batteries in the reference mode and the consumption mode are different as described above, it is possible to calculate the deterioration rate of the storage battery in the consumption mode from the ratio of the time required for raising and lowering the predetermined voltage width of both storage batteries. . Therefore, also in the said structure, the full charge capacity of the storage battery of consumption mode can be set based on a deterioration rate.

  According to a sixth aspect of the present invention, at least one of a plurality of storage batteries connected to an electric load so as to be able to supply power is set as a storage battery in a consumption mode used for charging / discharging power, and the plurality of storage batteries Among these, after setting at least one of the storage modes except for the storage battery in the consumption mode to the reference mode used for calculating the deterioration rate of the storage battery, the storage battery in the reference mode at the time of charging or discharging at every predetermined period, and Based on the comparison of the time required for boosting or stepping down the predetermined voltage width of the storage battery in the consumption mode, the deterioration rate of the storage battery in the consumption mode is calculated, and further, based on the deterioration rate of the storage battery in the consumption mode The gist is to set the full charge capacity of the storage battery, and to calculate the remaining capacity of the storage battery in the consumption mode from the remaining capacity rate with reference to the full charge capacity.

  According to the above method, the deterioration rate of the storage battery in the consumption mode is calculated by comparing the time required for raising and lowering the predetermined voltage width of the storage battery in the consumption mode and the reference mode. Then, the full charge capacity of the battery is set based on the deterioration rate of the storage battery in the consumption mode. Through these steps, the remaining capacity of the storage battery in the consumption mode can be recognized with higher accuracy based on the full charge capacity.

  According to the present invention, in the power distribution system and the storage battery remaining capacity calculation method, the accurate remaining capacity of the storage battery can be calculated regardless of the presence or absence of deterioration.

The block diagram which shows the structure of the power distribution system in this embodiment. The block diagram which expanded a part of FIG. 1 in this embodiment. The flowchart which shows the process sequence of the capacity | capacitance setting program in this embodiment. The flowchart which shows the process sequence of the deterioration measurement program in this embodiment. The graph which shows the time which discharge of both the storage batteries in this embodiment requires.

A first embodiment that embodies a power distribution system according to the present invention will be described below with reference to FIGS.
As shown in FIG. 1, a home is provided with a power distribution system 1 that supplies power to various devices (such as lighting devices, air conditioners, home appliances, and audiovisual devices) installed in the home. The power distribution system 1 supplies various devices with electric power of a solar cell 3 that generates power using sunlight in addition to electric power of a commercial AC power supply (AC power supply) 2 for home use. Further, the power distribution system 1 also uses a fuel cell 4 that generates power by a chemical reaction of substances as a power source. The power distribution system 1 supplies power not only to the DC device 5 that operates by inputting a DC power supply (DC power supply) but also to the AC device 6 that operates by inputting an AC power supply (AC power supply).

  The power distribution system 1 is provided with a control unit 7 and a DC power distribution board (built-in DC breaker) 8 as a power distribution board of the system 1. The power distribution system 1 is provided with a control unit 9 and a relay unit 10 as devices for controlling the operation of the DC device 5 in the house.

  An AC distribution board 11 for branching an AC power supply is connected to the control unit 7 via an AC power line 12. The control unit 7 is connected to the commercial AC power supply 2 and the fuel cell 4 through the AC distribution board 11 and is connected to the solar cell 3 through the DC system power line 13. The control unit 7 takes in AC power from the AC distribution board 11 and DC power from the solar cell 3 and converts these powers into predetermined DC power as a device power source. Then, the control unit 7 outputs the converted DC power to the DC distribution board 8 via the DC system power line 14 or outputs it to the storage battery unit 16 via the DC system power line 15. To store electricity. The control unit 7 not only takes in AC power but also converts DC power of the solar cell 3 and the storage battery unit 16 into AC power and supplies it to the AC distribution board 11. The control unit 7 exchanges data with the DC distribution board 8 via the signal line 17.

  The DC distribution board 8 is a kind of breaker that supports DC power. The DC distribution board 8 branches the DC power input from the control unit 7 and outputs the branched DC power to the control unit 9 via the DC power line 18 or relays via the DC power line 19. Or output to the unit 10. Further, the DC distribution board 8 exchanges data with the control unit 9 via the signal line 20 and exchanges data with the relay unit 10 via the signal line 21.

  A plurality of DC devices 5 are connected to the control unit 9. These DC devices 5 are connected to the control unit 9 via a DC supply line 22 that can carry both DC power and data by a pair of lines. The DC supply line 22 superimposes a communication signal for transmitting data by a high-frequency carrier wave on a DC voltage serving as a power source for the DC device, so-called power line carrier communication. Transport to. The control unit 9 acquires the DC power supply of the DC device 5 via the DC power line 18 and controls which DC device 5 based on the operation command obtained from the DC distribution board 8 via the signal line 20. Know what to do. Then, the control unit 9 controls the operation of the DC device 5 by outputting a DC voltage and an operation command to the instructed DC device 5 via the DC supply line 22.

  A switch 23 that is operated when switching the operation of the DC device 5 in the house is connected to the control unit 9 via a DC supply line 22. In addition, a sensor 24 that detects a radio wave transmitted from an infrared remote controller, for example, is connected to the control unit 9 via a DC supply line 22. Therefore, not only the operation instruction from the DC distribution board 8 but also the operation of the switch 23 and the detection of the sensor 24, a communication signal is sent to the DC supply line 22 to control the DC device 5.

  A plurality of DC devices 5 are connected to the relay unit 10 via individual DC power lines 25, respectively. The relay unit 10 acquires the DC power supply of the DC device 5 through the DC power line 19 and determines which DC device 5 is to be operated based on an operation command obtained from the DC distribution board 8 through the signal line 21. To grasp. The relay unit 10 controls the operation of the DC device 5 by turning on / off the power supply to the DC power line 25 with respect to the instructed DC device 5 using a built-in relay. In addition, a plurality of switches 26 for manually operating the DC device 5 are connected to the relay unit 10, and the DC power line 25 is turned on and off by the relay by operating the switch 26, thereby enabling the DC unit 5 to operate the DC unit 5. The device 5 is controlled.

  The DC distribution board 8 is connected to a DC outlet 27 built in a house in the form of a wall outlet or a floor outlet, for example, via a DC power line 28. If a plug (not shown) of a DC device is inserted into the DC outlet 27, DC power can be directly supplied to the device.

  Further, between the AC distribution board 11 and the commercial AC power supply 2, a power meter 29 capable of remotely metering the usage amount of the commercial AC power supply 2 is connected. The power meter 29 is equipped with not only a function of remote meter reading of the amount of commercial power used, but also a function of power line carrier communication and wireless communication, for example. The power meter 29 transmits the meter reading result to an electric power company or the like via power line carrier communication or wireless communication.

  The power distribution system 1 is provided with a network system 30 that enables various devices in the home to be controlled by network communication. The network system 30 is provided with a home server 31 as a control unit of the system 30. The home server 31 is connected to a management server 32 outside the home via a network N such as the Internet, and is connected to a home device 34 via a signal line 33. The in-home server 31 operates using DC power acquired from the DC distribution board 8 via the DC power line 35 as a power source.

  A control box 36 that manages operation control of various devices in the home by network communication is connected to the home server 31 via a signal line 37. The control box 36 is connected to the control unit 7 and the DC distribution board 8 via the signal line 17 and can directly control the DC device 5 via the DC supply line 38. For example, a gas / water meter 39 capable of remotely metering the amount of gas used or the amount of water used is connected to the control box 36 and also connected to the operation panel 40 of the network system 30. The operation panel 40 is connected to a monitoring device 41 including, for example, a door phone slave, a sensor, and a camera.

  When the in-home server 31 inputs an operation command for various devices in the home via the network N, the home server 31 notifies the control box 36 of the instruction, and operates the control box 36 so that the various devices operate in accordance with the operation command. . The in-home server 31 can provide various information acquired from the gas / water meter 39 to the management server 32 through the network N, and accepts from the operation panel 40 that the monitoring device 41 has detected an abnormality. This is also provided to the management server 32 through the network N.

  Next, a specific configuration around the control unit 7 and the storage battery unit 16 will be described. As shown in FIG. 2, the control unit 7 includes a solar cell DC-DC converter (hereinafter referred to as a solar cell converter) 53 and a bidirectional converter 58.

The solar cell converter 53 converts the DC power input from the solar cell 3 into appropriate DC power and outputs it to the DC distribution board 8 and the bidirectional converter 58.
The bidirectional converter 58 converts the DC power from the solar cell 3 and the storage battery unit 16 into AC and also converts the AC power from the AC power source 2 and the fuel cell 4 into DC. Thus, by providing the bidirectional converter 58, AC power can be converted into DC power and transmitted to the DC system, or DC power can be converted into AC power and transmitted to the AC system.

  The storage battery unit 16 includes a controller 51, a series circuit of a first DC-DC converter (hereinafter referred to as a first converter) 55 and a first storage battery 61, and a second DC-DC converter (hereinafter referred to as a parallel connection). , Referred to as a second converter) 56 and a series circuit of the second storage battery 62. In this example, the full charge capacities of the storage batteries 61 and 62 when they are new are equal.

  The control unit 51 includes a non-volatile memory 51a, and a capacity setting program, a threshold value, and the like described later are stored in the memory 51a. The control unit 51 includes a timer 51b that measures times T1 and T2 required for discharging. The control unit 51 outputs a command signal related to charging / discharging of the first storage battery 61 to the first converter 55 and outputs a command signal related to charging / discharging of the second storage battery 62 to the second converter 56. Based on the command signal, the first converter 55 converts the electric power from the DC power line 14 into an appropriate electric power for the first storage battery 61 and outputs it, or the electric power from the first storage battery 61 is appropriately applied to the DC electric power line 14. Or convert it into a simple power. That is, the first converter 55 performs control related to charging / discharging of the first storage battery 61. Further, the first converter 55 includes a voltage detection circuit 63 that detects the voltage Vb <b> 1 of the first storage battery 61, and the detection result of the voltage detection circuit 63 is output to the control unit 51. Similarly to the first converter 55, the second converter 56 performs control related to charging / discharging of the second storage battery 62 based on a command signal from the control unit 51, and detects the voltage Vb2 of the second storage battery 62. The voltage detection circuit 63 that outputs the detection result to the control unit 51 is provided.

  The control unit 51 can calculate an SOC (State Of Charge) that is an index indicating the remaining rate based on the voltages Vb1 and Vb2 of both the storage batteries 61 and 62. Specifically, assuming that the voltage Vb1 of the first storage battery 61 at the time of full charge is the reference voltage Vm, the SOC is calculated as “(detection voltage Vb1 / reference voltage Vm) × 100” as a percentage. The control unit 51 and the voltage detection circuit 63 correspond to a remaining rate calculation unit.

  Here, deterioration of a storage battery is generally promoted by repeating charge and discharge. As the storage battery deteriorates, the full charge capacity of the battery decreases. For example, the full charge capacity of a new storage battery is 100 Wh, whereas a deteriorated storage battery of the same type as the new battery has a full charge capacity reduced by 20 Wh and a full charge capacity of 80 Wh. Even in such a case, the voltages of both storage batteries at the time of full charge are equal. Therefore, in order to accurately calculate the remaining capacity of the storage battery based on the SOC, it is necessary to reset the full charge capacity in consideration of the deterioration of the storage battery.

  Therefore, the full charge capacity of both storage batteries 61 and 62 is set in consideration of the deterioration of both storage batteries 61 and 62. That is, the control unit 51 executes a capacity setting program in order to set a full charge capacity according to deterioration. The program is executed according to the processing procedure shown in the flowchart of FIG.

  In starting the program, the control unit 51 sets one of the first storage battery 61 and the second storage battery 62 in advance in the reference mode and the other in the consumption mode. Here, description will be made assuming that the first storage battery 61 is set to the consumption mode and the second storage battery 62 is set to the reference mode. The second storage battery 62 in the reference mode is used for calculating a deterioration rate of the first storage battery 61 described later, and the first storage battery 61 in the consumption mode is used for charging and discharging power.

  As shown in FIG. 3, the control unit 51 starts normal operation after the second storage battery 62 in the reference mode is fully charged (S101). During normal operation, power is appropriately supplied to the AC device 6 and the DC device 5 in cooperation with various power supply sources such as the AC power source 2. At this time, the control unit 51 performs charge / discharge control on the first storage battery 61 in the consumption mode, and does not perform charge / discharge control on the second storage battery 62 in the reference mode. Then, the control unit 51 waits for a certain period (for example, one month) to elapse from the start of normal operation (NO in S103), and performs the process related to the next step S104 after the certain period has elapsed (YES in S103). . In step S104, the control unit 51 measures the deterioration of the first storage battery 61, more accurately calculates the deterioration rate. The deterioration rate is an index indicating the degree of deterioration of the storage battery, and is represented by a numerical value of 1 or less. For example, the deterioration rate of a new storage battery is zero. The deterioration rate calculation process will be described in detail later.

  Then, the control unit 51 sets the full charge capacity of the first storage battery 61 based on the calculated deterioration rate (S105). For example, when the deterioration rate is 0.2, the first storage battery 61 is determined to have a full charge capacity of 80% of the second storage battery 62 when fully charged. That is, when the full charge capacity of the second storage battery 62 is 100 Wh, the full charge capacity of the first storage battery 61 is set to 80 wh. Then, the control unit 51 switches between the reference mode and the consumption mode, sets the first storage battery 61 to the reference mode, and sets the second storage battery 62 to the consumption mode (S106). This ends the capacity setting program. The program is executed at a predetermined control cycle, and in the next program to be executed, the deterioration of the second storage battery 62 in the consumption mode is measured and the full charge capacity is set. That is, the consumption mode and the reference mode are switched every time the capacity setting program is executed.

  Next, the deterioration measurement process for the storage batteries 61 and 62 in the consumption mode will be described with reference to the flowchart shown in FIG. This flowchart is executed when the process proceeds to step S104 in the flowchart shown in FIG.

  First, the control part 51 makes both the storage batteries 61 and 62 into a full charge state (S201). And the discharge of both the storage batteries 61 and 62 which became a full charge state is started (S202). At this time, the control unit 51 starts measuring the time T1 required for discharging the first storage battery 61 and the time T2 required for discharging the second storage battery 62 through the timer 51b (S203). That is, as shown in the graph of FIG. 5, discharge is started from 4.2 V that is the voltages Vb1 and Vb2 of both the storage batteries 61 and 62 at the time of full charge, and at the same time, measurement of the times T1 and T2 is started. At this time, the discharge electric energy from both the storage batteries 61 and 62 is always controlled to be constant. When the voltage Vb1 of the first storage battery 61 is equal to or lower than the threshold value Va of 2.0 V (YES in S204), the measurement of the time T1 is ended (S205). Further, when the voltage Vb2 of the second storage battery 62 becomes equal to or lower than the threshold value Va of 2.0 V (YES in S206), the measurement of the time T2 is ended (S207).

  A deterioration rate is calculated based on both measured times T1 and T2. Here, for example, when the first storage battery 61 is deteriorated, its full charge capacity is smaller than that of the second storage battery 62. Therefore, as shown in the graph of FIG. 5, the rate of decrease in the voltage Vb <b> 1 of the first storage battery 61 is faster than the voltage Vb <b> 2 of the second storage battery 62. Therefore, the deterioration rate is calculated by “1− (time T1 / time T2)” on the assumption that the second storage battery 62 in the reference mode has not deteriorated (S208). For example, when the first storage battery 61 is not deteriorated at all, both times T1 and T2 are equal, “time T1 / time T2” is 1, and the deterioration rate is zero. When the first storage battery 61 is deteriorated and there is a relationship of “time T1: time T2 = 8: 10”, the deterioration rate is 0.2. Then, the control unit 51 returns this deterioration rate to the main routine. When the deterioration rate is 0.2, the first storage battery 61 is set to 80% of the full charge capacity of the second storage battery 62 as described above. The control unit 51, the timer 51b, and the voltage detection circuit 63 correspond to a deterioration rate calculation unit.

  When the deterioration measurement is performed on the second storage battery 62, the deterioration rate is calculated based on the time T1 required to discharge the first storage battery 61, that is, “1- (time T2 / time T1)”. The full charge capacity of the second storage battery 62 is set according to the rate.

  As described above, the reference mode and the consumption mode are alternately switched between the storage batteries 61 and 62 every time the capacity setting program is executed, so that only one storage battery 61 and 62 is set to the consumption mode. Since the number of times of charging / discharging is made uniform, deterioration of the storage batteries 61 and 62 can be suppressed.

  Moreover, the control part 51 can calculate a more exact remaining capacity based on SOC by setting the full charge capacity of both the storage batteries 61 and 62 according to a deterioration rate. Specifically, when the full charge capacity of the first storage battery 61 is set to 80 Wh and the SOC is 50%, the remaining capacity is calculated to be exactly 40 Wh. Therefore, the control unit 51 can determine how long the DC device 5 and the AC device 6 can be operated with the remaining capacity of the first storage battery 61. This is particularly effective when the minimum necessary DC device 5 and AC device 6 are operated with electric power from the storage batteries 61 and 62 in the consumption mode during a power failure. That is, in such a situation, it is possible to suppress the sudden decrease in the SOC due to the decrease in the full charge capacity of the storage batteries 61 and 62 due to the deterioration, and the suddenly impossible power supply.

  Since the storage batteries 61 and 62 in the reference mode are fully charged by the process in step S101 of FIG. 3, the power can be used as an emergency power source during a power failure. Normally, the power of the storage batteries 61 and 62 in the consumption mode is used, and the power of the storage batteries 61 and 62 in the reference mode is not used. However, when the power supply from the AC power source 2 or the like to the AC device 6 and the DC device 5 becomes impossible due to a power failure, and the remaining capacity of the storage batteries 62 and 61 in the consumption mode becomes zero, the storage battery in the reference mode By supplying the power of 62 and 61 to the AC device 6 and the DC device 5, it is possible to supply power to the AC device 6 and the DC device 5 in an emergency in a longer period.

As described above, according to the embodiment described above, the following effects can be obtained.
(1) Based on the deterioration rate of the storage batteries 61 and 62, the exact full charge capacity of the storage batteries 61 and 62 is set. As a result, even when the storage batteries 61 and 62 are deteriorated, the remaining capacity can be calculated with higher accuracy based on the SOC (residual capacity rate) with the accurate full charge capacity as a reference.

  (2) The deterioration rate of the storage batteries 61 and 62 in the consumption mode is calculated by comparing the times T1 and T2 required for discharging the storage batteries 61 and 62 set in the consumption mode and the reference mode. The control unit 51 sets the full charge capacity of the storage batteries 61 and 62 based on the deterioration rate of the storage batteries 61 and 62 in the consumption mode. Thereby, even when the storage batteries 61 and 62 in the consumption mode are deteriorated, the remaining capacity can be calculated with higher accuracy based on the SOC based on the accurate full charge capacity.

  (3) After setting the full charge capacity of the storage batteries 61 and 62 in the consumption mode, the storage batteries 61 and 62 in the reference mode and the consumption mode are switched. Here, the storage mode batteries 61 and 62 in which charging and discharging are repeated are more likely to deteriorate than the storage mode batteries 62 and 61 in the reference mode. In that respect, according to the present invention, since the storage batteries 61 and 62 in the consumption mode in which charging and discharging are repeated every predetermined period are switched to the reference mode, the deterioration of the storage batteries 61 and 62 can be suppressed. 62 lifespan can be extended.

  (4) The storage batteries 62 and 61 in the reference mode are used as an emergency power source. Therefore, even when the supply of power from the storage batteries 61 and 62 in the consumption mode and other power systems is stopped, the power supply from the storage batteries 62 and 61 in the reference mode to the AC device 6 and the DC device 5 can be performed. .

In addition, the said embodiment can be implemented with the following forms which changed this suitably.
In the above embodiment, the second storage battery 62 in the reference mode is in a fully charged state as shown in step S101 in the flowchart of FIG. However, in step S101, power may be discharged from the second storage battery 62 in the reference mode, and the remaining capacity of the second storage battery 62 may be zero. In this case, since the remaining capacity of the second storage battery 62 is zero, natural discharge does not occur, and the life of the second storage battery 62 can be extended. Further, step S101 may be omitted completely.

  In the above embodiment, the times T1 and T2 from the fully charged voltages Vb1 and Vb2 (4.2V) to the threshold value Va of 2.0V are measured. It is not limited to 2.0V. For example, by setting the threshold value Va to a value closer to 4.2 V, the times T1 and T2 can be measured in a shorter time, and the deterioration rate can be calculated, and thus the capacity setting can be speeded up. In addition, by setting the threshold value Va to a smaller value, it is possible to derive a more accurate time T1, T2 and a deterioration rate based on them. It is also possible to calculate the deterioration rate by measuring times T1 and T2 during which power is supplied from both the storage batteries 61 and 62 to the AC device 6 and the DC device 5.

  In the above embodiment, the deterioration rate is calculated based on the times T1 and T2 required for discharging. However, it is also possible to calculate the deterioration rate based on the times T1 and T2 required for charging. In this case, for example, the times T1 and T2 required for the voltages Vb1 and Vb2 to reach from 4.2 V to 4.2 V are measured, and the deterioration rate is calculated from the times T1 and T2.

  In the above embodiment, the voltage detection circuit 63 of both the converters 55 and 56 has a function of detecting the voltages Vb1 and Vb2 as battery voltage detection means. However, the voltages Vb1 and Vb2 are separate from the converters 55 and 56. You may provide the voltage detection apparatus etc. which detect this.

  In the above embodiment, the reference mode and the consumption mode are switched between the storage batteries 61 and 62. However, for example, the first storage battery 61 is used for consumption and the second storage battery 62 is used for reference, and switching between the two modes may not be performed. Thereby, the process etc. which concern on switching of both modes are omissible. In this case, the full charge capacity of the first storage battery 61 for consumption is set to 100 Wh, whereas the full charge capacity of the second storage battery 62 for reference may be reduced to about 10 Wh, for example. In this case, the time T2 required for the voltage Vb2 of the second storage battery 62 to change from 4.2V to 2.0V is shortened. However, time T1 and time T2 have a certain correlation. That is, “time T1 / time T2” decreases as the first storage battery 61 deteriorates. Therefore, by multiplying the time T2 by the proportional constant a, the deterioration rate can be calculated by “1- [time T1 / (time T2 × proportional constant a)]” as described above. The proportional constant a is set so that “time T1 / (time T2 × proportional constant a)” is 1, in other words, the deterioration rate is zero, in a state where the first storage battery 61 is not deteriorated. Has been. Thus, the storage battery unit 16 and by extension, the power distribution system 1 can be comprised more compactly by making the 2nd storage battery 62 of a reference mode into a small capacity | capacitance.

  In the above embodiment, as a means for calculating the deterioration rate, the control unit 51 performs a comparison operation of the times T1 and T2 required for discharging. However, as long as the deterioration rate can be calculated, the deterioration rate is not limited to the above-described means. For example, the deterioration rate may be calculated based on the discharge amount of each of the storage batteries 61 and 62. Here, as the full charge capacity of the storage battery decreases due to deterioration, for example, the discharge amount of the storage battery when the voltage of the storage battery is decreased by a predetermined value decreases. Therefore, it is possible to calculate the deterioration rate by comparing the discharge amounts of the storage batteries 61 and 62. Similarly, it is also possible to calculate the deterioration rate by comparing the charge amounts of both storage batteries 61 and 62.

  In the above embodiment, as means for calculating the remaining rate (SOC) of both storage batteries 61, 62, the control unit 51 uses the reference voltage Vm and the voltage Vb1, of both storage batteries 61, 62 detected by the voltage detection circuit 63. Comparison of Vb2 was performed. However, as long as the remaining rate (SOC) can be calculated, the sensor is not limited to the above means, and for example, a sensor that detects a current (charge / discharge current) flowing into and out of each of the storage batteries 61 and 62 is provided, and the sensor detects it. The SOC may be calculated by integrating the current value.

  In the above embodiment, the pair of storage batteries 61 and 62 is provided, but the number of storage batteries may be any number. By providing a large number of storage batteries, the total capacity of the storage battery can be improved. Moreover, you may be comprised with the single storage battery. In this case, the consumption mode and the reference mode are not set, and the deterioration rate of a single storage battery is calculated as follows, for example. That is, a time T2 required for discharging a new storage battery is stored in the memory 51a of the control unit 51 in advance. This time T2 corresponds to the time T2 required for discharging the second storage battery 62 shown in FIG. 5 in the above embodiment. Then, for example, the control unit 51 stores in the memory 51a the time T1 from 4.2V, which is the voltage of the single storage battery at the time of full charge, to the threshold value Va (2.0V) or less due to discharging. Compared with the time T1 to be performed, more precisely, the deterioration rate can be calculated by the calculation performed in step S208 of FIG.

  DESCRIPTION OF SYMBOLS 1 ... Power distribution system, 2 ... Commercial alternating current power supply (AC power supply), 3 ... Solar cell, 4 ... Fuel cell, 7 ... Control unit, 12 ... Cross flow connection line, 13-15 ... DC system power line, 16 ... Storage battery unit, DESCRIPTION OF SYMBOLS 51 ... Control part, 51a ... Memory, 51b ... Timer, 53 ... Solar cell converter, 55 ... 1st converter, 56 ... 2nd converter, 58 ... Bidirectional converter, 61 ... 1st storage battery, 62 ... 2nd storage battery, 63 ... Voltage detection circuit (battery voltage detection means).

Claims (6)

A storage battery connected to an electrical load so as to be able to supply power;
A remaining rate calculating means for calculating a remaining rate of the storage battery;
A deterioration rate calculating means for calculating a deterioration rate of the storage battery;
The full charge capacity of the storage battery is set based on the deterioration rate of the storage battery calculated by the deterioration rate calculation means for each predetermined period, and the remaining capacity of the storage battery is determined from the remaining capacity rate based on the full charge capacity. A power distribution system comprising: a control unit that calculates The power distribution system according to claim 1,
A plurality of the storage batteries are provided,
Battery voltage detecting means for detecting the voltage of each storage battery,
The control unit sets at least one of the plurality of storage batteries as a consumption mode storage battery used for charging and discharging electric power, and removes at least one of the plurality of storage batteries from the consumption mode storage battery. Set to the reference mode used for calculating the deterioration rate of the storage battery in the consumption mode,
The deterioration rate calculating means is based on a comparison of time required for stepping up or stepping down a predetermined voltage width of the reference mode storage battery and the consumption mode storage battery detected by the battery voltage detection means. To calculate
The control unit sets a full charge capacity of the storage battery in the consumption mode based on the calculated deterioration rate of the storage battery in the consumption mode, and determines the consumption mode from the remaining rate based on the full charge capacity. A power distribution system for calculating a remaining capacity of a storage battery. The power distribution system according to claim 2.
The control unit switches a storage battery in the consumption mode to a reference mode and switches a storage battery in the reference mode to a consumption mode after setting a full charge capacity of the storage battery in the consumption mode. In the power distribution system according to claim 2 or 3,
A power distribution system using the reference mode storage battery as an emergency power source. The power distribution system according to claim 2.
A power distribution system using a storage battery having a small full charge capacity as a storage battery in the reference mode as compared with a storage battery in a consumption mode. At least one of a plurality of storage batteries connected to an electric load so as to be able to supply power is set as a storage battery in a consumption mode used for charging and discharging power, and the storage battery in the consumption mode is excluded from the plurality of storage batteries , After setting at least one of the reference mode for calculation of the deterioration rate of the storage battery,
For each predetermined period, based on the comparison of the time required for boosting or stepping down the predetermined voltage width of the storage battery in the reference mode and the storage battery in the consumption mode at the time of charging or discharging, the deterioration rate of the storage battery in the consumption mode is calculated,
Further, based on the deterioration rate of the storage battery in the consumption mode, the full charge capacity of the storage battery in the consumption mode is set, and the remaining capacity of the storage battery in the consumption mode is calculated from the remaining capacity rate based on the full charge capacity Remaining capacity calculation method.

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