WO2014103218A1

WO2014103218A1 - Electricity storage apparatus charge/discharge system

Info

Publication number: WO2014103218A1
Application number: PCT/JP2013/007307
Authority: WO
Inventors: 美香桐本; 阿部　裕司; 徹石川; 計美大倉
Original assignee: 三洋電機株式会社
Priority date: 2012-12-27
Filing date: 2013-12-12
Publication date: 2014-07-03
Also published as: JP2016034170A

Abstract

An electricity storage apparatus charge/discharge system (16) is provided with: an electricity storage apparatus (18) configured from a plurality of storage battery units (24); a control apparatus (20); and a storage apparatus (22) that stores correlation data (36) that correlates a charge/discharge target SOC, charge/discharge current rate, and capacity deterioration degree of the electricity storage apparatus (18) to each other. The control apparatus (20) includes: a charge/discharge request acquiring unit (28) that acquires a charge/discharge request; a charge/discharge target SOC setting unit (30) that sets the charge/discharge target SOC to reduce the capacity deterioration degree of the electricity storage apparatus (18) corresponding to the acquired charge/discharge request; a charge/discharge current rate setting unit (32) that sets the charge/discharge current rate; and a parallel number setting unit (34) that sets the parallel number of the storage battery units (24).

Description

Power storage device charge / discharge system

The present invention relates to a power storage device charging / discharging system.

Regarding charge / discharge control of a power storage device, Patent Document 1 discloses that charge / discharge is controlled within a low deterioration voltage range set based on a battery deterioration rate of a lithium ion secondary battery. Patent Document 2 collects data on the relationship between the operation and deterioration of the lead storage battery, evaluates the relationship between the operation and deterioration, and obtains a plurality of operation conditions such as charging intervals and the sensitivity regarding a decrease in battery capacity, respectively. It is stated that life estimation is performed using Taguchi method.

Patent Document 3 describes charging in a constant current region in which the magnitude of the charging current is constant and charging in the constant voltage region in which the magnitude of the charging voltage is constant when charging the secondary battery.

JP 2009-70777 A JP 2010-159661 A Japanese Patent Laid-Open No. 5-111184

Regarding the power storage device, when examining the relationship between the capacity degradation degree indicating the degree of capacity reduction caused by the charge / discharge and the charge / discharge SOC that is the target SOC (State Of Charge) as the center of charge / discharge, It has been found that the degree of capacity degradation differs even with the same charge / discharge target SOC, depending on the specifications and internal structure of the apparatus. In addition, it was found that the relationship between the charge / discharge current rate indicating the magnitude of the charge / discharge current value and the capacity deterioration degree differ depending on the specification of the power storage device and the internal structure.

Therefore, it is desirable to appropriately set the charge / discharge target SOC and the charge / discharge current rate according to the specifications and internal structure of the power storage device so as to reduce the capacity deterioration degree of the power storage device.

A power storage device charging / discharging system according to the present invention includes a power storage device that can be charged or discharged, a charge / discharge target SOC that is a target when charging or discharging the power storage device, and a charge / discharge current that flows when charging or discharging the power storage device And a control device that performs charge / discharge control of the power storage device based on the rate and the capacity deterioration degree that occurs when the power storage device is charged or discharged.

According to the present invention, the charge / discharge target SOC and the charge / discharge current rate can be appropriately set according to the specifications and internal structure of the power storage device so as to reduce the capacity deterioration degree of the power storage device.

It is a figure which shows the structure of the electric power transmission and distribution network containing the electrical storage apparatus charging / discharging system of embodiment of this invention. In the electrical storage apparatus charging / discharging system of embodiment of this invention, it is a figure which shows the relationship between charging / discharging target SOC, charging / discharging electric current rate, and capacity degradation degree. In the electrical storage apparatus charging / discharging system of embodiment of this invention, it is a figure which shows an example of the relevant data which shows the relationship between charging / discharging target SOC, charging / discharging electric current rate, and capacity degradation degree. It is a figure which shows the relationship of use temperature about the related data of FIG. It is a figure which shows the relationship of charging / discharging log | history about the related data of FIG. It is a figure which shows the example of the related data different from FIG. In the power storage device charging / discharging system according to the embodiment of the present invention, it is a flowchart showing a procedure for setting a charging / discharging target SOC and setting a charging / discharging current rate according to a calculated required charging / discharging amount. It is a figure which shows the structure of the vehicle drive control system containing the electrical storage apparatus charging / discharging system of embodiment of this invention. It is a figure which shows the structure of the control apparatus which estimates a capacity degradation degree etc. in the electrical storage apparatus charging / discharging system of embodiment of this invention. It is a figure which shows performing charge of an electrical storage apparatus in a constant current charge period and a constant voltage charge period. It is a figure which shows the change of the internal resistance value of an electrical storage apparatus in the electrical storage apparatus charging / discharging system of embodiment of this invention. It is a figure which shows the relationship between SOC of an electrical storage apparatus, and Voc in the electrical storage apparatus charging / discharging system of embodiment of this invention. In the electrical storage apparatus charging / discharging system of embodiment of this invention, it is a figure which shows the change of the 2nd degradation degree which is a capacity degradation degree in a constant voltage charge period. It is a figure which shows the estimation of the capacity deterioration degree performed over the whole area of charge in the electrical storage apparatus charging / discharging system of embodiment of this invention. In the electrical storage apparatus charging / discharging system of embodiment of this invention, it is a figure which shows the change of a 1st deterioration degree when SOC which is a parameter of a charging current pattern is changed. In the electrical storage apparatus charging / discharging system of embodiment of this invention, it is a figure which shows the change of a 1st deterioration degree when the charging current rate which is a parameter of a charging current pattern is changed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, as the charge / discharge control of the power storage device that keeps the charge / discharge target SOC within a predetermined range, the power storage device charge / discharge system under the ancillary service and the drive control system of the vehicle equipped with the power storage device will be described. These are illustrative examples, and the present invention can be applied to other charge / discharge amount control systems.

The values of the capacity of the power storage device, the charge / discharge target SOC, the charge / discharge current rate, and the like described below are examples for explanation, and can be appropriately changed according to the specifications of the power storage device charge / discharge system.

In the following, the same or corresponding elements are denoted by the same reference symbols in all drawings, and redundant description is omitted.

FIG. 1 is a diagram showing a configuration of the power transmission / distribution network 10. This power transmission / distribution network 10 is a power storage device of an independent power generation company having a system power source 12 such as a thermal power plant of a power company, a factory 14 that is a consumer of power, a power generation facility such as a solar cell, and a power storage device. The charge / discharge system 16 and the system controller 13 are connected. The power storage device charging / discharging system 16 is a network that supplies power to the factory 14 together with the system power supply 12. The factory 14 becomes a load of the power transmission / distribution network 10.

The system control device 13 is a device managed by an electric power company or the like. The system control device 13 detects load fluctuations in the power transmission / distribution network 10 (that is, fluctuations in demand for power), and gives instructions for maintaining a balance between supply and demand of the power transmission / distribution network 10 as a whole. To at least one of the systems 16. When the supply and demand balance is lost, the frequency of electricity transmitted and distributed in the power transmission and distribution network 10 (hereinafter also referred to as “system frequency”) varies. If the difference between the system frequency and the reference frequency exceeds a certain range, there is a possibility that a malfunction of some devices and generators on the consumer side will occur.

The system control device 13 can instruct the system power supply 12 via the communication network to adjust the power generation output according to the load fluctuation. Specifically, the power generation output is instructed to increase when the power demand exceeds the power supply, and the power generation output is instructed to decrease when the power demand falls below the power supply.

Also, the system control device 13 can instruct the power storage device charging / discharging system 16 via the communication network to release or absorb power to the power transmission / distribution network 10 in accordance with load fluctuations. Specifically, when the power demand exceeds the power supply, the power transmission / distribution network 10 is instructed to release power. When the power demand falls below the power supply, the power transmission / distribution network 10 is instructed to absorb power.

The change of the power generation output by the former system power supply 12 takes several minutes to 10 minutes. Since the adjustment of power supply by the latter power storage device charging / discharging system 16 can be instantaneously performed, it is particularly effective for instantaneous load fluctuations.

As described above, when the power storage device charging / discharging system 16 is connected to the power transmission / distribution network 10, the factory 14 is supplied with power even if the power supply / demand balance by the system power supply 12 such as an electric power company is disrupted. The ancillary service for stabilizing the system frequency can be received by adjusting the power of the system controller 13. Under the ancillary service, the power storage device charging / discharging system 16 sets the fluctuation widths of the central SOC and the SOC for the charge / discharge target SOC for the power storage device to a predetermined value so as not to disturb the power supply / demand balance of the power transmission / distribution network 10. It is required to perform charge / discharge control within the range.

The power storage device charging / discharging system 16 includes a power storage device 18, a control device 20 that performs charge / discharge control thereof, and a storage device 22 connected to the control device 20.

The power storage device 18 includes a storage battery unit unit in which a plurality of storage battery units 24 are connected in parallel, and a parallel number changing unit 26 that can change the parallel number of the plurality of storage battery units 24.

As the storage battery unit 24, a lithium ion assembled battery, which is a rechargeable secondary battery, is used. Instead of the lithium ion assembled battery, another secondary battery or a high capacity capacitor can be used. As the secondary battery, a nickel-metal hydride battery, a lead storage battery, or the like can be used.

The parallel number changing unit 26 collects one terminal of each of the plurality of storage battery units 24 as one terminal, and interconnects a desired number of the other terminals into one terminal so that the power storage device 18 is desired. The number of storage battery units 24 is connected in parallel. The parallel number changing unit 26 includes a plurality of switches. For example, in the case where 16 storage battery units 24 are provided, assuming that N of the 16 batteries are connected in parallel by the parallel number changing unit 26, the N storage battery units 24 connected in parallel to each other include the power storage device 18. It becomes. In this case, N can be arbitrarily set from 1 to 16. By using the parallel number changing unit 26, the charge / discharge current value of each storage battery unit 24 can be taken as I, and the power storage device 18 can take out or accept the charge / discharge current value of N × I.

The control device 20 exchanges information with the power storage device 18 and also exchanges information with the storage device 22, and the power storage device 18 is based on the charge / discharge target SOC, the charge / discharge current rate, and the capacity deterioration level of the power storage device 18. Charge / discharge control. The control device 20 can be configured by hardware or a combination of hardware and software. The control device 20 includes a charge / discharge request acquisition unit 28 that acquires a charge / discharge amount necessary for stabilizing the system frequency calculated by the system control device 13 as a charge / discharge request, and a power storage device corresponding to the acquired charge / discharge request. Similarly, the charge / discharge target SOC setting unit 30 that sets the charge / discharge target SOC in a direction to reduce the capacity deterioration degree of 18, and similarly, charge / discharge in a direction to reduce the capacity deterioration degree of the power storage device 18 in response to the charge / discharge request. A charge / discharge current rate setting unit 32 that sets the current rate and a parallel number setting unit 34 that sets the parallel number of the storage battery units 24 instructed to the parallel number changing unit 26 are included. All or part of the functions may be executed by executing a program on a program execution device (for example, a microcomputer that can be mounted on the control device 20).
The storage device 22 is used, for example, as a memory for storing a program and data used in the control device 20, and in this case, in particular, the association that relates the charge / discharge target SOC, the charge / discharge current rate, and the capacity deterioration degree of the power storage device 18 A case where the data 36 is stored will be described.

Before describing the contents of the related data 36, the charge / discharge target SOC, the charge / discharge current rate, and the capacity deterioration degree of the power storage device 18 will be described with reference to FIG. In FIG. 2, the rectangular frame 19 shown at the left end schematically shows the state of charge of the power storage device 18, and the nine waveform diagrams shown on the right side are when the power storage device 18 is charged and discharged. It is a figure for demonstrating a capacity degradation degree.

The rectangular frame 19 at the left end in FIG. 2 indicates the state of charge of the power storage device 18, and is 1.0 Ah when fully charged. This numerical value is an example for explanation, and other numerical values may be used. The power storage device 18 is repeatedly charged and discharged, so that the ampere hour (Ah), which is a current-time product at the time of full charge, decreases. Here, 1.0 Ah when fully charged is a value in an initial state in which the power storage device 18 is manufactured.

In the rectangular frame 19, three ampere-

hour areas

37, 38, and 39 are shown. From the smaller ampere hour value, a region 37 centered at 0.1 Ah, a region 38 centered at 0.4 Ah, and a region 39 centered at 0.7 Ah. These regions are the charge / discharge target SOC.

The region 37 is a region having a width of 0.05 Ah around the center of 0.1 Ah. Here, since 0.1 Ah is 10% of the charge state when 1.0 Ah, which is the initial full charge state of the power storage device 18, is used as a reference, this is the center SOC of the charge / discharge target SOC = 10%. I will call it. Thus, the charge / discharge target SOC is defined as an index of charge / discharge with respect to the initial full charge state of the power storage device 18. In the example of FIG. 2, the charge / discharge target SOC is a value indicating how much ampere hour the charge / discharge is performed with respect to 1.0 Ah which is the initial full charge state of the power storage device 18.

Using such a definition, the charge / discharge target SOC of the region 37 is the center SOC = 10%, and the range of the region 37 has a value of 5% to 15% with a width of ± 5% before and after that. In the example of FIG. 2, it means charging / discharging with a width of 0.05 Ah to 0.15 Ah.

Similarly, the charge / discharge target SOC of the region 38 is the center SOC = 40%, and the range of the region 38 has a value of 35% to 45% with a width of ± 5% before and after that. In the example of FIG. 2, it means charging / discharging with a width of 0.35 Ah to 0.45 Ah. Similarly, the charge / discharge target SOC of the region 39 is center SOC = 70%, and the range of the region 39 is ± 5% before and after that, and has a value of 65% to 75%. In the example of FIG. 2, it means charging / discharging with a width of 0.65 Ah to 0.75 Ah.

The waveform chart arranged on the right side of the rectangular frame 19 shows how much the capacity of the power storage device 18 is deteriorated when charging / discharging from 0 cycle to 300 cycles is performed within each charge / discharge target SOC range. It is a schematic diagram which changes and shows the magnitude | size of an electric current value. The charge / discharge current rate is used as the charge / discharge current value. The charge / discharge current rate is a value obtained by dividing the ampere hour indicating the initial full charge state of the power storage device 18 by 1 hour, and is 1.0 C. In the example of FIG. 2, since the ampere hour indicating the initial full charge state of the power storage device 18 is 1.0 Ah, the charge / discharge current rate is 1.0 C = 1.0 A. When the charge / discharge current value is 0.5A, the charge / discharge current rate is 0.5C, and when the charge / discharge current value is 1.5A, the charge / discharge current rate is 1.5C.

FIG. 2 shows three waveform diagrams when the charge / discharge current rate is 0.5 C, 1.0 C, and 1.5 C. The three waveform diagrams arranged on the right side of the region 37 show that when the charge / discharge target SOC is within the range of 10% ± 5%, the charge / discharge current rate is set to 0.5C, 1.0C, 1.5C, and 0 cycles. It shows how much the width of charging / discharging narrows when charging / discharging from 300 to 300 cycles.

The charge / discharge target SOC = 10% ± 5% is 0.1 Ah ± 0.05 Ah in FIG. 2 and is in the range of 0.05 Ah to 0.15 Ah. The charge / discharge current rate = 0.5C is 0.5A. Therefore, it takes (0.05 Ah / 0.5 A) = 0.1 h to charge from the charge / discharge target SOC = 0.1 Ah to the charge / discharge target SOC = 0.15 Ah. Similarly, it takes {(0.15 Ah−0.05 Ah) /0.5 A} = 0.2 h to discharge from the charge / discharge target SOC = 0.15 Ah to the charge / discharge target SOC = 0.05 Ah. If the charge / discharge current rate is set to 1.0 C, the time required for the charge / discharge can be halved. Similarly, if the charge / discharge current rate is 1.5 C, the time required for these charge / discharges can be reduced to 1/3.

When the power storage device 18 is repeatedly charged and discharged, the ampere hour that can be fully charged is gradually reduced. In the rightmost waveform diagram of the three waveform diagrams on the right side of the region 37, the left end of the waveform diagram is when charging / discharging starts, that is, the number of charging / discharging cycles = 0, and the right end of the waveform diagram is charging / discharging. The number of cycles = 300 cycles is shown. A thick AC waveform line indicates a change in ampere hour that can be brought to a fully charged state when the charge / discharge current rate is 1.5 C, and an envelope outline thereof is indicated by two broken lines.

When the number of charge / discharge cycles = 0, the interval between two broken lines = A is 1.0 Ah, which is the ampere hour at which the power storage device 18 can be fully charged. The interval between the two broken lines when the number of charge / discharge cycles = 300 cycles = B is an ampere hour that allows the power storage device 18 to be fully charged when charge / discharge is repeated 300 cycles. In this way, the power storage device 18 gradually decreases in ampere hours that can be fully charged when charging and discharging are repeated. B / A (× 100%) is the capacity retention rate of the power storage device 18 when charging and discharging are repeated. {1- (B / A)} (× 100%) is the capacity deterioration degree of the power storage device 18 when charging and discharging are repeated.

As is clear from the definition, a relational expression of capacity maintenance rate + capacity deterioration rate = 1 holds between the capacity maintenance rate and the capacity deterioration rate of the power storage device 18. That is, since the capacity maintenance ratio and the capacity deterioration degree are in a dual relationship, setting the charge / discharge target SOC so as to reduce the capacity deterioration degree sets the charge / discharge target SOC so that the capacity maintenance ratio increases. Can be replaced. Performing charge / discharge control based on the capacity degradation degree is essentially the same as performing charge / discharge control based on the capacity maintenance rate by reversing the increase / decrease direction, so for convenience of explanation, either one is used. Take an example and explain.

In the nine waveform diagrams on the right side of FIG. 2, the difference in the charge / discharge target SOC is indicated by the density of the oblique lines, and the difference in the charge / discharge current rate is indicated by the thickness of the AC waveform line.

In the example of FIG. 2, the capacity deterioration degree of the power storage device 18 varies depending on the charge / discharge target SOC and also varies depending on the charge / discharge current rate. In the case of the power storage device 18 of FIG. 2, when compared with the same charge / discharge current rate, the charge / discharge target SOC is in the range of 40% ± 5%, compared with the other charge / discharge target SOC ranges. There is little capacity deterioration. Further, in the example of FIG. 2, when compared with the same charge / discharge target SOC, the capacity deterioration degree is smaller as the charge / discharge current rate is smaller.

The related data 36 stored in the storage device 22 is the association of the charge / discharge target SOC, the charge / discharge current rate, and the capacity deterioration degree of the power storage device 18. FIG. 3 is a diagram showing the related data 36. The related data 36 is obtained by performing an experimental measurement or the like on the power storage device 18 in advance. In this example, the related data 36 is composed of two maps. One of the maps has the charge / discharge current rate as a parameter, the charge / discharge target SOC on the horizontal axis, and the capacity maintenance ratio B / A on the vertical axis. Another map is obtained by changing the way of view, with the charge / discharge target SOC as a parameter, the horizontal axis indicates the charge / discharge current rate, and the vertical axis indicates the capacity maintenance ratio B / A. In these maps, instead of the capacity maintenance rate, the capacity deterioration degree may be taken on the vertical axis.

In the example of FIG. 3, the optimum ranges 40 and 42 are ranges in which the capacity retention rate is stably high. By setting the charge / discharge target SOC and the charge / discharge current rate so that the capacity maintenance ratio is in the optimum ranges 40 and 42, the capacity deterioration degree of the power storage device 18 can be reduced.

In the above description, the related data 36 has been described as a map. However, if one or two of the charge / discharge target SOC, the charge / discharge current rate, and the capacity deterioration degree are used as search keys, the rest can be read out as described above. It may be other than the map shown. For example, it may be a look-up table format, a mathematical expression, or the like that can read out the capacity deterioration degree using the charge / discharge target SOC and the charge / discharge current rate as search keys. Alternatively, it may be a ROM format in which a capacity deterioration degree is input and a combination of a charge / discharge target SOC and a charge / discharge current rate that is the capacity deterioration degree is output.

In the above example, the use temperature of the power storage device 18 is not taken into account for the related data 36 indicating the relationship among the charge / discharge target SOC, the charge / discharge current rate, and the capacity deterioration degree. When various characteristics of the power storage device 18 are temperature-dependent, the related data 36 may be prepared for each use temperature of the power storage device 18. FIG. 4 is a diagram showing each related data when the operating temperature of the power storage device 18 is 25 ° C., the temperature is 10 ° C. on the low temperature side, and 60 ° C. on the high temperature side. The parameters of the related data at each temperature, the contents of the horizontal axis, and the vertical axis are the same as in FIG.

FIG. 4 shows two related maps when various characteristics of the power storage device 18 are temperature-dependent. In the example of FIG. 4, the value of the highest capacity maintenance ratio is lower than the highest capacity maintenance ratio at 25 ° C. in both cases where the temperature is lower than 25 ° C. and when the temperature is higher. It becomes. Further, when the temperature is lower than 25 ° C. and when the temperature is higher than 25 ° C., the dependency of the capacity maintenance rate on the charge / discharge current rate is moderate as compared to the case of 25 ° C.

In the above, the capacity maintenance rate or the capacity deterioration degree was obtained based on the initial fully charged state in which the power storage device 18 was manufactured. For the power storage device 18 that already has a usage history, a capacity maintenance rate or a capacity reduction rate based on a fully charged state that has already been reduced due to the usage history may be used. In this case, the related data 36 is arranged for each usage history of the power storage device 18. FIG. 5 is a diagram illustrating an example of each related data when the usage history of the power storage device 18 is 100 cycles, 300 cycles, and 1000 cycles. The related data parameters, the horizontal axis, and the vertical axis in each usage history are the same as those in FIG.

In the example of FIG. 5, as the number of charge / discharge cycles as the use history increases, the characteristic line indicating the capacity retention rate is translated in a direction to decrease the capacity retention rate.

In the above description, the power storage device 18 is described as having the related data 36 shown in FIG. If the plurality of power storage devices 18 have the same specifications and the same structure, the related data 36 is substantially the same except for variations in manufacturing. In the case of the power storage devices 18 having different specifications and structures, the related data is different. FIG. 6 is a diagram illustrating an example of related data 35 of power storage devices having different specifications and structures. The parameters, the vertical axis, and the horizontal axis of the related data 35 are the same as the related data 36 in FIG. In FIG. 6, the optimum ranges 44 and 46 are ranges in which the capacity retention rate is stably high. Compared with FIG. 3, it can be seen that there is an optimum range 44 in the higher value of the charge / discharge target SOC. As described above, the charge / discharge target SOC and the charge / discharge current rate that can reduce the capacity deterioration degree differ depending on the specifications and structure of the power storage device.

The operation of the above configuration, in particular, the functions of the control device 20 and the contents of the related data 36 stored in the storage device 22 will be described in more detail with reference to FIG. FIG. 7 shows that in the power storage device charge / discharge system 16, the capacity deterioration degree of the power storage device 18 is reduced while satisfying the charge / discharge amount necessary for stabilizing the system frequency calculated by the system control device 13 as a charge / discharge request. Thus, it is an example of a flowchart showing a procedure for setting the charge / discharge target SOC and setting the charge / discharge current rate. Each procedure in FIG. 7 corresponds to each processing procedure of charge / discharge control in the control device 20.

First, initial conditions of each component of the power storage device charging / discharging system 16 are set. Then, the center SOC of the charge / discharge target SOC is set (S10). The charge / discharge target SOC including the central SOC may be set from the overall system settings of the power transmission / distribution network 10, but the power storage device charge / discharge system 16 is economically separated from the system power supply 12 and the factory 14. When it is a power generation company, the setting is performed based on the maximum profit of the power storage device charging / discharging system 16.

As an example, it is assumed that the center SOC of the charge / discharge target SOC is set under a policy of setting the capacity deterioration degree of the power storage device 18 to be equal to or less than a preset value. When the characteristics of power storage device 18 are indicated by related data 36, center SOC of charge / discharge target SOC is set to an appropriate value in a range between about 40% and about 60%. When the characteristics of power storage device 18 are indicated by related data 35, center SOC of charge / discharge target SOC is set to an appropriate value in a range between about 65% and about 80%. Thus, when the degree of capacity deterioration of power storage device 18 is taken into consideration, the center SOC of charge / discharge target SOC is set to a different value depending on the specification, structure, etc. of power storage device 18. In the following, an example is given of cases where the characteristics of the power storage device 18 are temperature-dependent and there is a usage history. The description will be continued assuming that the power storage device 18 has the characteristics of the related data 36.

Note that the central SOC of the charge / discharge target SOC may not necessarily be set to a value that causes the capacity deterioration degree to be equal to or less than a preset value depending on the usage state of the power storage device 18 or the like. For example, when the power storage device charging / discharging system 16 is charged by receiving power from the system power supply 12 at night and discharging to the factory 14 in the daytime, the charge / discharge target SOC of the power storage device charging / discharging system 16 is set in the early morning when the night power feeding is completed. The center SOC is set to a value close to the fully charged state of power storage device 18. Further, when the power storage device charging / discharging system 16 is a system in which charging is performed by power generation of a solar battery, the center SOC of the charging / discharging target SOC is set according to the sunshine situation.

When the center SOC of the charge / discharge target SOC is set, next, the related data 36 of the power storage device 18 is referred to (S12). Since the related data 36 is stored in the storage device 22 for each use temperature and use history, the use temperature and use history of the power storage device 18 can be designated and read from the storage device 22. When the related data 36 is read, under the center SOC of the set charge / discharge target SOC, the charge / discharge current rate and the parallel number are set in a direction in which the capacity deterioration degree of the power storage device 18 is not more than a preset value. Done. In FIG. 7, as the condition S setting (S14), the charge / discharge target SOC = SOC (S), the capacity deterioration degree = DG (S), the charge / discharge current rate = CR (S), and the parallel number = N (S) are set. Has been shown to be.

An example of setting the condition S will be described with reference to the related data 36 in FIG. When the center SOC of the charge / discharge target SOC is set to 40% in the charge / discharge target SOC setting unit 30 of the control device 20 (S10), the center SOC = SOC (S) = 40%. The target maximum value of the capacity deterioration degree is set to, for example, capacity deterioration degree = DG (S) = 0.1. DG (S) = 0.1 means that the capacity retention ratio B / A = 0.9. The charge / discharge current rate setting unit 32 sets the charge / discharge current rate so that the capacity deterioration degree when the center SOC is 40% is DG (S) = 0.1. Here, it is assumed that the charge / discharge current rate = CR (S) = 0.5C. The parallel number is set to the standard parallel connection number of the power storage device 18. If the standard parallel connection number is 12, the parallel number = N (S) = 12.

When the condition S is set as described above, charge / discharge control of the power storage device 18 is executed under the condition S. The system control device 13 calculates the amount of charge / discharge at which the factory 14 can stably supply power by looking at the power balance that can be supplied by the system power supply 12 and the demand balance of the factory 14 that is a load.
When the power that can be supplied by the system power supply 12 is 100 kW less than the demand of the factory 14, the system control device 13 gives a discharge request to the charge / discharge request acquisition unit 28 so as to discharge 100 kW. When the power that can be supplied by the system power supply 12 is 100 kW higher than the demand of the factory 14, the system control device 13 gives a charge request to the charge / discharge request acquisition unit 28 so as to charge 100 kW. The charge / discharge amount calculated by the system control device 13 is acquired as a charge / discharge request by the charge / discharge request acquisition unit 28 of the control device 20 (S16).

When the charge / discharge request is acquired, it is determined whether or not the condition S is sufficient to satisfy the request (S18). If the determination is positive, the charge / discharge control under the condition S is maintained, and the setting is completed. If the determination is negative, in order to achieve both a charge / discharge request and a reduction in the degree of deterioration of the power storage device 18, the process proceeds to S20 and subsequent steps.

When S18 is negative, first, the center SOC = SOC (S) is not changed, and the charge / discharge current rate setting unit 32 determines whether the charge / discharge request can be satisfied by changing the charge / discharge current rate. (S20). In the example of FIG. 3, when SOC (S) = 40%, the capacity deterioration degree of the power storage device 18 is small regardless of whether the charge / discharge current rate is 0.5C, 1.0C, or 1.5C. For example, when the charge / discharge current rate is set to 1.5 C, if SOC (S) = 40%, the capacity deterioration degree of the power storage device 18 is suppressed as compared to when the center SOC is 10% and the center SOC is 80%. Can do. In this case, the capacity deterioration degree is a value larger than DG (S). For example, it is only necessary to set a predetermined capacity deterioration degree equal to or less than the maximum value DG (max).

Therefore, the charge / discharge current rate can be satisfied by changing the charge / discharge current rate = CR (S) = 0.5C to three times the charge / discharge current rate = 1.5C, and the charge / discharge current rate is tripled. If the capacity deterioration degree which becomes large by this is DG (max) or less, the center SOC = SOC (S) can be set, and the determination in S20 is affirmed.

Therefore, as condition 1, charging / discharging target SOC = SOC (S), capacity degradation level = DG (1), charging / discharging current rate = CR (1), and the number of parallels = N (S) are set. The charge / discharge control is performed. In this example, CR (1) is selected and set so that DG (1) is equal to or less than DG (max) (S22).

In the above example, when the characteristics of the power storage device 18 is the center SOC of the charge / discharge target SOC = 40% and the charge / discharge current rate is 1.5 C or less, the capacity deterioration degree is DG (max) or less. CR (1) can be set to a value satisfying the charge / discharge request in a range of 1.5C or less. The change setting of the charge / discharge current rate is executed by the function of the charge / discharge current rate setting unit 32 of the control device 20.

If the determination in S20 is negative, the parallel number setting unit 34 of the control device 20 determines whether it is possible to satisfy the charge / discharge request by changing the parallel number from N (S) (S24). For example, in the above example, when the charge / discharge current rate is 1.5C, the capacity deterioration degree can be DG (max) or less, but at 1.5C, the charge / discharge request cannot be satisfied and the charge / discharge current rate is 1.8C. If the charge / discharge request can be satisfied, the parallel number is changed from N (S) = 12 to N (1) = 15 of 12 × (1.8C / 1.5C) = 14.4 or more. By setting the parallel number in this way, the charge / discharge current rate can be maintained at CR (1) = 1.5C, and the capacity deterioration degree of the power storage device 18 can be maintained at DG (max) or less. Affirmed.

Therefore, as condition 2, charge / discharge target SOC = SOC (S), capacity deterioration degree = DG (1), charge / discharge current rate = CR (1), and parallel number = N (1) are set. The charge / discharge control is performed. Here, CR (1) is selected and set so that DG (1) is equal to or less than DG (max), and N (1) is equal to or less than N (max) which is the maximum value of the parallel number. (S26). The change setting of the parallel number is executed by the function of the parallel number setting unit 34 of the control device 20.

When the determination in S24 is negative, the charge / discharge target SOC setting unit 30 of the control device 20 determines whether the charge / discharge current rate is CR (S) and the charge / discharge target SOC can be satisfied by changing the charge / discharge target SOC. (S28). As an example of this case, there is a case where the capacity deterioration degree of the power storage device 18 exceeds DG (max) at the charge / discharge current rate that satisfies the charge / discharge request.
In this case, in the example of FIG. 3, the charge / discharge target SOC at which the capacity deterioration degree is equal to or less than a preset value is around 50%, so the SOC (S) is changed to 50% and the capacity deterioration degree is set to DG. It is determined whether it is possible to make (max) or less.

When the determination of S28 is affirmed, as condition 3, charge / discharge target SOC = SOC (1), capacity deterioration level = DG (1), charge / discharge current rate = CR (S), parallel number = N (1) It is set and charge / discharge control is performed under the conditions. Here, SOC (1) and CR (S) are set so that DG (1) has a value equal to or less than DG (max), and N (1) is N (max) which is the maximum value of the parallel number. ) Is selected to be as follows (S30). The change setting of the charge / discharge target SOC is executed by the function of the charge / discharge target SOC setting unit 30 of the control device 20.

The order of the determination procedure of S20 and the determination procedure of S28 may be interchanged. That is, if the determination in S18 is negative, the determination in S28 may be performed. If the determination in S28 is negative, the determination in S20 may be performed, and then the determination in S24 may be performed.

When the determination in S28 is negative, the capacity deterioration degree of the power storage device 18 exceeds DG (max) to satisfy the charge / discharge request. In that case, appropriate conditions are set in consideration of the cost increase accompanying the capacity deterioration of the power storage device 18 and the benefit of supplying power to the factory 14 by satisfying the charge / discharge request (S32).

As described above, the system control device 13 calculates the charge / discharge amount to be stably supplied to the factory 14 which is a load, and the power storage device charge / discharge system 16 stores the charge / discharge amount while satisfying the charge / discharge request. The charge / discharge target SOC is set, the charge / discharge current rate is set, etc. so as to reduce the capacity deterioration degree of the device 18, and the charge / discharge control of the power storage device 18 is executed.

In the above description, the charge / discharge control of the power storage device 18 under the ancillary service has been described as an example in which the charge / discharge target SOC needs to be within a predetermined range in the charge / discharge control of the power storage device 18. That is, the power storage device charging / discharging system 16 connected to the power transmission / distribution network 10 together with the system power supply 12 of an electric power company or the like keeps the charge / discharge target SOC within a predetermined range so as not to disturb the power supply / demand balance of the network. Is required.

Other examples include charge / discharge control of a power storage device mounted on a vehicle. In this case, charge / discharge control is performed so that the SOC of the power storage device falls within a predetermined range so that the power storage device does not become overcharged or overdischarged, and suppresses the degree of capacity deterioration due to repeated charge / discharge.
FIG. 8 is a diagram showing a configuration of the vehicle drive control system 50 including the power storage device charging / discharging system 48. The vehicle drive control system 50 includes an engine 54, a rotating electrical machine 56, and a power storage device charge / discharge system 48 mounted on the vehicle 52. The rotating electrical machine 56 is a power device mounted on the vehicle 52 and corresponds to the factory 14 which is a load in FIG.

The power storage device charging / discharging system 48 has substantially the same configuration as the power storage device charging / discharging system 16 of FIG. That is, it includes a power storage device 58 mounted on the vehicle 52, a control device 60 that performs charge / discharge control thereof, and a storage device 62. Control device 60 includes a charge / discharge request acquisition unit 64, a charge / discharge target SOC setting unit 66, and a charge / discharge current rate setting unit 68, and storage device 62 has a charge / discharge target SOC and a charge / discharge current of power storage device 58. The related data 70 for associating the rate and the capacity deterioration degree is stored.

The control device 60 performs the same procedure as described in FIG. 7 except that the parallel number of the power storage devices 58 is not changed, and reduces the charge / discharge request from the vehicle and the capacity deterioration degree of the power storage device 58. The charge / discharge target SOC and the charge / discharge current rate are set to appropriate values so that

Further, when the battery charge is used as a power source, the SOC decreases. Conversely, when regeneration or charging from a generator is performed, the SOC increases. Since this change is always generated in combination in the vehicle, the input / output current rate may be limited in accordance with the current SOC.
Further, the time change of the SOC is predicted from the value of the input / output current rate, the current rate that can be input / output at each prediction time is calculated, and information such as the amount of current that can be output before a certain time is sent to the vehicle. You may be notified.

As another embodiment, a demand response for ensuring the supply and demand balance of the power transmission / distribution network 10 based on the demand power amount of the load calculated in advance to stabilize the demand supply in the power transmission / distribution network 10. An example is shown.

The amount of power required in the factory 14 serving as a load is estimated in advance from the past power consumption, calculated in advance, stored in the storage device 22 (not shown), and power that can be supplied by the system power supply 12 From the demand power of the factory 14 that is a load based on the calculated value, the demand supply in the power transmission / distribution network 10 may be stabilized. You may control a current rate so that the peak of the electric power which the factory 14 uses may be equalized. Also in the case of the present embodiment, the central SOC and the charge / discharge current rate can be set so as to reduce the capacity deterioration degree of the power storage device 18 by the procedure shown in FIG.

As described above, according to the above configuration, two variables of the charge / discharge target SOC of the power storage device and the charge / discharge current rate are appropriately selected. By doing so, it is possible to perform appropriate charge / discharge control while satisfying both the charge / discharge request and the reduction in the capacity deterioration degree of the power storage device.

Hereinafter, a method for estimating the capacity deterioration degree when charging and discharging the power storage device 18 and a method for reducing the capacity deterioration degree will be described. Hereinafter, charging of the power storage device 18 will be described in detail, but the discharge can be similarly applied only by reversing the current flow.

FIG. 9 is a diagram showing a configuration of the control device 20 for estimating the capacity deterioration degree and reducing the capacity deterioration degree. In addition to the charge / discharge request acquisition unit 28 and the like described in FIG. 1, the control device 20 uses the capacity deterioration degree estimation unit 80 and a pattern for changing the charge / discharge current rate according to the SOC as a current rate pattern. A current rate pattern setting unit 82 that sets a current rate pattern so as to reduce current, and a variation for evaluating how a variation in a current rate pattern parameter affects a capacity deterioration degree when setting a current rate pattern An influence evaluation unit 84 is included.

As an example of estimating the capacity deterioration degree over the entire charging / discharging section of the power storage device 18, the entire section of the charging process of the power storage device 18 will be described. FIG. 10 is a diagram illustrating a method for charging the power storage device 18. FIG. 10A is a diagram in which the horizontal axis indicates SOC, and the vertical axis indicates the voltage value between terminals of the power storage device 18. The horizontal axis in FIG. 10B is the same SOC as in FIG. Current value.

As shown in FIG. 10, constant current charging is performed in which the magnitude of the charging current is a constant value I _CC at the initial stage of charging control for the power storage device 18. This period is a constant current charging period and corresponds to charging with the charging current rate described with reference to FIG. As a result, when the inter-terminal voltage value gradually rises to V _CV which is a predetermined CV voltage value, the inter-terminal voltage is maintained at a constant value and charging is continued. This period is a constant voltage charging period. As a result, the charging current value gradually decreases, and when the charging end current value _IE is reached, the charging control is terminated.

Since charging is performed at a constant charging current rate in the constant current charging period, the capacity deterioration degree is obtained based on the contents described in FIGS. 3 to 6 if the magnitude of the charging current rate and the SOC are known. Can do. Therefore, if the capacity deterioration degree in the constant voltage charging period can be obtained, the capacity deterioration degree in all sections of the charging control in FIG. 10 can be estimated. In the following, the capacity deterioration degree when the charge / discharge current rate described in FIGS. 3 to 6 is constant is defined as the first deterioration degree, and the capacity deterioration degree due to charging under a constant voltage after the SOC at which constant voltage charging starts is indicated. The second deterioration degree is assumed.

When the second deterioration degree in the constant voltage charging period was experimentally examined, it was found that the capacity deterioration degree tends to increase as the SOC when starting the constant voltage charging is smaller. Here, assuming that the SOC at the start of constant voltage charging is SOC _CV , if the SOC _CV knows the open circuit voltage Voc of the power storage device 18 at the time of starting constant voltage charging, the SOC _CV is the open circuit voltage value Voc of the power storage device 18. It can be obtained based on the Voc-SOC relationship indicating the relationship between the state of charge SOC.
The open circuit voltage Voc of the power storage device 18 when starting constant voltage charging can be obtained based on the voltage drop due to the CV voltage V _CV and the internal resistance value R of the power storage device 18 when starting constant voltage charging. That is, the open circuit voltage Voc = V _CV −I _CC × R corresponding to SOC _CV is obtained. Note that V _CV , which is a CV voltage value, can be set as an empirical value if the specifications of the power storage device 18 are determined. For example, when the power storage device 18 is a lithium ion cell, V _CV is set as a voltage value in the range of about 4.1 V to about 4.4 V.

FIG. 11 is a diagram illustrating a relationship between the internal resistance value R of the power storage device 18 and the number of cycles in which the power storage device 18 is charged and discharged. R ₀ when the number of cycles = 0 is an initial internal resistance value of the power storage device 18 and can be obtained experimentally if the specifications of the power storage device 18 are determined. By using FIG. 11, the internal resistance value R of the power storage device 18 that has been repeatedly charged and discharged can be obtained. As a result, the open circuit voltage Voc = V _CV −I _CC × R when starting constant voltage charging can be calculated.

FIG. 12 is a diagram illustrating an example of the Voc-SOC relationship of the power storage device 18. In the Voc-SOC relationship, the horizontal axis is SOC and the vertical axis is Voc. FIG. 12 can be experimentally obtained as a general characteristic of a lithium ion battery. Using FIG. 12, the SOC _CV can be obtained as the SOC corresponding to the open circuit voltage Voc when starting constant voltage charging.

FIG. 13 is a diagram simulating the result of experimentally determining the relationship between the SOC _CV and the second deterioration degree for a lithium ion battery. The horizontal axis is SOC _CV and the vertical axis is the second deterioration degree. As shown in FIG. 13, the smaller the SOC _CV when starting constant voltage charging, the greater the capacity deterioration degree. In this example, when the SOC _CV is 70% or more, the capacity deterioration degree is almost constant.

By using the contents described in FIGS. 3 to 6 and the data in FIG. 13, it is possible to estimate the capacity deterioration degree for all the sections of the charge / discharge control of the power storage device 18. Here, the capacity deterioration degree estimation process over the entire section of the charging control process of the power storage device 18 will be described with reference to FIG.
This process can be executed by the function of the capacity deterioration degree estimating unit 80 of the control device 20.

FIG. 14A is a diagram showing how the charging current value is changed as the charging progresses when full charge control is performed on the power storage device 18, and the horizontal axis indicates the SOC and the vertical axis indicates The charging current value is shown by the charging current rate. In FIG. 10, charging is performed at a constant current value during the constant current charging period. However, from one example of related data indicating the relationship between the charge / discharge target SOC, the charge / discharge current rate, and the capacity deterioration degree in FIG. Even if the charging current rate is set to a large value around 50%, the increase in the capacity deterioration degree is small, so the charging current rate is set to be larger than that in other SOC regions. In a region excluding the region where the SOC is around 50%, the capacity deterioration degree increases at the same charging current rate as the region where the SOC is around 50%, so the charging current rate is reduced. Thus, the charging current rate is changed according to the SOC so that the capacity maintenance rate is improved.
For example, if the SOC at which constant voltage charging starts is 80%, the SOC is charged at 1.0 C when the SOC is 0% to 40%, and is charged at 1.5 C when the SOC is 40% to 60%. When the SOC is between 60% and 80%, the battery is charged at 0.5C. When the SOC is between 80% and 100%, charging is performed under a constant value of V _CV as a constant voltage charging period.

FIG. 14 (b) is a diagram in which the horizontal axis coincides with the SOC of FIG. 14 (a), and the vertical axis represents the first and second deterioration levels. As for the first deterioration degree, when the SOC, which is the constant current charging period, is 0% to 80%, the capacity maintenance ratio on the vertical axis in FIG. 3A is rewritten with capacity deterioration degree = (1−capacity maintenance ratio). Was defined as the first deterioration degree. As the second degree of deterioration, the data of FIG. 13 was used for SOC 80% to 100%, which is a constant voltage charging period. In this case, the capacity deterioration degree over the entire SOC section is estimated as follows.

Since the battery is charged at 1.0 C when the SOC is 0% to 40%, the first deterioration degree for 1.0 C is integrated between SOC 0% and 40% using FIG. And Since the SOC is charged at 1.5C when the SOC is 40% to 60%, the first deterioration degree for 1.5C is integrated between the SOC 40% and 60% using FIG. Let D2. Since the SOC is charged at 0.5C when the SOC is 60% to 80%, the first deterioration degree for 0.5C is integrated between the SOC 60% and 80% using FIG. Let D3. When the SOC is between 80% and 100%, the SOC at which constant voltage charging is started is 80%. Therefore, the second deterioration degree at the time of SOC 80% is obtained from FIG. 13, and this is set as D4. In FIG. 14B, the magnitudes of the integrated values D1, D2, and D3 of the first deterioration degree are indicated by hatching.

In this example, the capacity deterioration degree over the entire SOC section can be calculated as the capacity deterioration degree estimated value of all sections = D1 + D2 + D3 + D4.

In FIG. 14, the charging current rate is changed in accordance with the SOC. However, the current rate pattern, which is a charging current rate pattern, varies slightly due to disturbance due to estimation error of capacity degradation degree, sensor accuracy, and the like. Even so, it is desirable that the capacity deterioration rate does not change much. Hereinafter, with reference to FIG. 15 and FIG. 16, for a plurality of current rate pattern candidates, a variation influence degree that is a change in the capacity deterioration degree with respect to a change in a parameter constituting the current rate pattern is evaluated, and a plurality of current rate patterns are evaluated. An example of determining a current rate pattern that minimizes the influence of variation from among the pattern candidates will be described. This process is executed by the functions of the current rate pattern setting unit 82 and the variation influence degree evaluation unit 84 of the control device 20.

FIG. 15 is a diagram showing a change in the first deterioration degree when the SOC that is a parameter of the current rate pattern is changed. 15 (a), (b), and (c) are each composed of two figures, an upper stage and a lower stage. Each lower figure corresponds to (a) in FIG. This corresponds to (b) of FIG. 15A, 15B and 15C, the current rate pattern of the same SOC as the current rate pattern of FIG. 14 is indicated by a solid line 86, and the SOC is + 5% from the current rate pattern of the solid line 86. The fluctuating current rate pattern is indicated by a one-dot chain line 87, and the current rate pattern in which the SOC is fluctuated by −5% from the current rate pattern indicated by the solid line 86 is indicated by a broken line 88.

That is, the current rate pattern of the solid line 86 is charged at 1.0 C when the SOC is 0% to 40%, charged at 1.5 C when the SOC is 40% to 60%, and the SOC is 60% to 80%. % Is a pattern of charging at 0.5C. The current rate pattern of the alternate long and short dash line 87 is charged at 1.0C when the SOC is between 0% and 45%, charged at 1.5C when the SOC is between 45% and 65%, and the SOC is between 65% and 80%. In the pattern, charging is performed at 0.5C. Further, the current rate pattern of the broken line 88 indicates that the SOC is charged at 1.0 C when the SOC is 0% to 35%, is charged at 1.5 C when the SOC is 35% to 55%, and the SOC is 55% to 80%. % Is a pattern of charging at 0.5C.

In the example of FIG. 15, the SOC is shifted by ± 5% as a parameter constituting the current rate pattern with respect to the current rate pattern described in FIG. The variation influence degree, which is a change in the capacity deterioration degree with respect to the fluctuation, is determined by which of the first deterioration degrees D1, D2, and D3 described in FIG. 14 in the upper diagrams of FIGS. 15 (a), (b), and (c). It can be evaluated by how it changes. The second degree of degradation D4 changes when the SOC changes, but does not change in this example.

In FIG. 15A, the first deterioration degree with respect to SOC variation = 0% is set as D1 ₀ , D2 ₀ , D3 ₀ , and each is indicated by hatching. FIG. 15A is the same as FIG. 14, and D1 ₀ , D2 ₀ , and D3 ₀ correspond to D1, D2, and D3 in FIG. In FIG. 15B, the first deterioration degree with respect to the SOC variation = + 5% is set as D1 ₊ , D2 ₊ , D3 ₊ , and each is shown by hatching. In FIG. 15C, the first deterioration degree with respect to SOC variation = −5% is indicated by D1 ₋ , D2 ₋ , and D3 ₋ , and each is indicated by hatching.

FIG. 16 is a diagram showing a change in the first deterioration degree when the charging current rate that is a parameter of the current rate pattern is changed. 16 (a), (b), and (c) are each composed of two diagrams, an upper stage and a lower stage. Each lower figure corresponds to (a) in FIG. This corresponds to (b) of FIG. In the lower part of FIGS. 16A, 16B, and 16C, a current rate pattern having the same charging current rate as the current rate pattern of FIG. 14 is indicated by a solid line 86, and charging is performed from the current rate pattern of the solid line 86. A current rate pattern in which the current rate is changed by +0.1 C is indicated by a one-dot chain line 89, and a current rate pattern in which the charging current rate is changed by −0.1 C from the current rate pattern of the solid line 86 is indicated by a broken line 90.

That is, the current rate pattern of the solid line 86 is charged at 1.0 C when the SOC is 0% to 40%, charged at 1.5 C when the SOC is 40% to 60%, and the SOC is 60% to 80%. % Is a pattern of charging at 0.5C. The current rate pattern of the alternate long and short dash line 89 is charged at 1.1 C when the SOC is 0% to 40%, charged at 1.6 C when the SOC is 40% to 60%, and the SOC is 60% to 80%. In the pattern, the battery is charged at 0.6C. Further, the current rate pattern of the broken line 90 indicates that the SOC is charged at 0.9C when the SOC is 0% to 40%, is charged at 1.4C when the SOC is 40% to 60%, and the SOC is 60% to 80%. % Is a pattern of charging at 0.4C.

In the example of FIG. 16, with respect to the current rate pattern described in FIG. 14, the charging current rate is shifted by ± 0.1 C as a parameter constituting the current rate pattern. The variation influence degree, which is a change in the capacity deterioration degree with respect to the fluctuation, is the first deterioration degree D1, D2, D3 described in FIG. 14 in the upper diagrams of FIGS. 16 (a), (b), and (c). It can be evaluated by how it changes. 16A, 16B, and 16C, the charging current rates are 0.4C, 0.5C, 0.6C, 0.9C, 1.0C, 1.1C, 1 .4C, 1.5C. The relationship between the first deterioration level and the SOC at 1.6C is shown. Note that the second deterioration degree D4 changes as the SOC changes, but does not change in this example.

In FIG. 16A, the first deterioration degree with respect to the fluctuation of the charging current rate = 0% is defined as E1 ₀ , E2 ₀ , E3 ₀ , and each is indicated by hatching. FIG. 16A is the same as FIG. 14, and E1 ₀ , E2 ₀ and E3 ₀ correspond to D1, D2 and D3 in FIG. In FIG. 16B, the first deterioration degree with respect to the fluctuation of the charging current rate = + 0.1 C is defined as E1 ₊ , E2 ₊ , E3 ₊ , and each is shown by hatching. In FIG. 16 (c), the first deterioration degree with respect to the fluctuation of the charging current rate = −0.1 C is set as E1 ₋ , E2 ₋ , E3 ₋ , and each is shown by hatching.

In this way, with respect to the current rate pattern described with reference to FIG. 14, it is possible to evaluate the degree of influence on the first deterioration degree due to fluctuations in the SOC and the charging current rate. Similarly, with respect to a current rate pattern different from that described with reference to FIG. 13, it is possible to evaluate the degree of influence on the first deterioration level due to changes in the SOC and the charging current rate. Therefore, by preparing a plurality of current rate patterns as candidates and evaluating and comparing the variation influence degree that is the degree of influence on the first deterioration degree with respect to the variation of the SOC and the charging current rate, the variation influence degree is obtained. The minimum current rate pattern can be determined. Therefore, if a current rate pattern candidate that minimizes the influence of variation is set as a current rate pattern, charge / discharge control that is robust against parameter fluctuation due to disturbance due to an estimation error of the capacity change rate, sensor accuracy, and the like can be achieved.

DESCRIPTION OF SYMBOLS 10 Power transmission / distribution network, 12 system power supply, 13 system control apparatus, 14 factory, 16,48 Power storage device charging / discharging system, 18, 58 Power storage apparatus, 19 Rectangular frame, 20,60 Control apparatus, 22,62 Storage device, 24 Storage battery unit, 26 parallel number changing unit, 28, 64 charge / discharge request obtaining unit, 30, 66 charge / discharge target SOC setting unit, 32, 68 charge / discharge current rate setting unit, 34 parallel number setting unit, 35, 36, 70 Data, 37, 38, 39 area, 40, 42, 44, 46 Optimal range, 50 Vehicle drive control system, 52
Vehicle, 54 engine, 56 Rotating electric machine, 80 Capacity deterioration level estimation unit, 82 Current rate pattern setting unit, 84 Variation effect level evaluation unit, 86 Solid line, 87, 89 Dash-dot line, 88, 90 Dashed line.

Claims

A power storage device that can be charged or discharged; and
Based on a charge / discharge target SOC that is a target when charging or discharging the power storage device, a charge / discharge current rate that flows when charging or discharging the power storage device, and a capacity deterioration degree that occurs when charging or discharging the power storage device A control device for performing charge / discharge control of the power storage device,
A power storage device charging / discharging system.
In the electrical storage apparatus charging / discharging system of Claim 1,
A storage device for storing relevant data relating the charge / discharge target SOC of the power storage device, the charge / discharge current rate, and the capacity deterioration degree;
The control device includes:
A charge / discharge request acquisition unit for acquiring, as a charge / discharge request, a charge / discharge amount to be discharged from the power storage device and charged to the power storage device;
A charge / discharge target SOC setting unit that sets the charge / discharge target SOC in a direction to reduce the capacity deterioration degree with reference to the related data with respect to the charge / discharge request acquired by the charge / discharge request acquisition unit;
With reference to the related data, a charge / discharge current rate setting unit that sets the charge / discharge current rate in a direction to reduce the capacity deterioration degree;
With
A power storage device charge / discharge system that sets at least one of the charge / discharge target SOC and the charge / discharge current rate.
In the electrical storage apparatus charging / discharging system of Claim 2,
The related data stored in the storage device is data obtained when the power storage device is charged or discharged every certain current rate and every SOC region at a certain number of times. .
4. The power storage device charge / discharge system according to claim 3, wherein the related data is data obtained when the power storage device is charged or discharged at a certain temperature.
In the electrical storage apparatus charging / discharging system of any one of Claim 2 to 4,
The power storage device is configured by connecting a plurality of storage battery units in parallel, and includes a parallel number changing unit capable of changing the parallel number,
The control device includes:
Charge / discharge at the charge / discharge current rate set in the direction of reducing the capacity degradation degree by the charge / discharge current rate setting means with respect to the charge / discharge current value according to the charge / discharge request obtained from the charge / discharge request acquisition means. The power storage device charging / discharging system in which the parallel number changing unit changes the charge / discharge current rate and the charge / discharge current value to the parallel number when both of the requirements cannot be satisfied.
The power storage device charge / discharge system according to any one of claims 1 to 5, wherein the power storage device is connected to a power transmission and distribution network together with a load and a power source, and the charge / discharge request acquired by the charge / discharge request unit is: A power storage device charging / discharging system, which is a necessary charging / discharging amount for instantaneously instantaneously securing a power supply / demand balance of the network and stabilizing the system frequency of the network.
In the electrical storage apparatus charging / discharging system of any one of Claim 1 to 5,
The power storage device is mounted on a vehicle, and the power storage device can be discharged to a power device mounted on the vehicle.
The said control apparatus is a electrical storage apparatus charging / discharging system which performs charging / discharging control with respect to the said electric power apparatus from the said electrical storage apparatus.
In the electrical storage apparatus charging / discharging system of any one of Claim 1 to 5,
The power storage device is connected to a power transmission / distribution network together with a load and a power source, and the charge / discharge request acquired by the charge / discharge request unit is based on the power demand of the load calculated in advance. Power storage device charging / discharging system, which is a necessary charge / discharge amount for securing the supply and demand balance of the power supply and stabilizing the supply and demand in the power transmission and distribution network.
In the electrical storage apparatus charging / discharging system of any one of Claim 1 to 5,
The charge / discharge current rate setting unit includes:
A power storage device charging / discharging system that changes the charge / discharge current rate according to an SOC that changes by charging or discharging the power storage device.
In the electrical storage apparatus charging / discharging system of Claim 9,
A capacity deterioration degree estimation unit that estimates a capacity deterioration degree according to the charge / discharge current rate, and estimates a capacity deterioration degree over all sections of charging or discharging of the power storage device based on the estimated capacity deterioration degrees. A power storage device charging / discharging system.
In the electrical storage apparatus charging / discharging system of Claim 10,
The pattern of changing the charge / discharge current rate for each SOC interval for changing the charge / discharge current rate is defined as a current rate pattern, and the capacity deterioration degree with respect to a change in parameters constituting the current rate pattern is determined for a plurality of current rate pattern candidates. A variation impact evaluation unit that evaluates the variation impact that is a change;
A power storage device charging / discharging system comprising: a current rate pattern setting unit that sets a current rate pattern candidate that minimizes the degree of variation influence as a current rate pattern.
In the electrical storage apparatus charging / discharging system of Claim 11,
The variation impact evaluation unit
A power storage device charging / discharging system for evaluating a variation influence degree with respect to a charging / discharging current rate or an SOC interval.
In the electrical storage apparatus charging / discharging system of Claim 10,
The control device includes:
A constant current charging period in which charging of the power storage device is performed under a constant current value over the entire section, and after the voltage value between the terminals of the power storage device reaches a predetermined CV voltage value due to constant current charging, the terminal voltage is It is divided into a constant voltage charging period in which charging is further performed while maintaining a constant value,
A power storage device charging / discharging system including a capacity deterioration degree estimation unit that estimates a first capacity deterioration degree that occurs during a constant current charging period and a second capacity deterioration degree that occurs during a constant voltage charging period.
In the electrical storage apparatus charging / discharging system of Claim 13,
For charging in the constant voltage charging period, a storage device is provided that stores related data associating a relationship between a constant voltage charging start SOC, which is an SOC when the constant voltage charging period starts, and the second capacity deterioration degree. ,
The control device includes:
A constant voltage charge start SOC estimation unit that estimates a constant voltage charge start SOC corresponding to the CV voltage value based on the CV voltage value and an internal resistance value of the power storage device;
A power storage device charging / discharging system that obtains a second capacity deterioration level corresponding to the estimated constant voltage charging start SOC with reference to related data.