Monitoring device, power system and program

Abstract

To provide a monitoring device that can satisfactorily control a self-sustained operation when a plurality of distributed power sources is operated in parallel.SOLUTION: A monitoring device 2 includes a receiving unit 21, a total value calculation unit 22, a distribution rate calculation unit 23A, a setting unit 24A, a first calculation unit 25, a second calculation unit 26, and a transmission unit 27. For each inverter device 1, the setting unit 24A calculates an active power target value from an active power total value calculated by the total value calculation unit 22 and a distribution rate calculated by the distribution rate calculation unit 23A, and calculates a reactive power target value from a reactive power total value calculated by the total value calculation unit 22 and the distribution rate calculated by the distribution rate calculation unit 23A. The first calculation unit 25 is supplied with the active power target value and an active power output value of each inverter device 1 and calculates a voltage phase command value of each inverter device 1. The second calculation unit 26 is supplied with the reactive power target value and a reactive power output value of each inverter device 1 and calculates a voltage amplitude command value of each inverter device 1.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a monitoring device, a power system, and a program. [Background technology]

[0002] In recent years, research on distributed power sources using solar cells, storage batteries, etc. Generally, a distributed power source is connected to a power grid, and performs power control by using the phase of the system voltage of the power grid as its own internal phase (for example, Patent Document 1).

[0003] A distributed power source may operate independently when it cannot be connected to the power grid due to a power outage, etc. In this case, since the distributed power source cannot detect the phase from the system voltage of the power grid, it oscillates its own internal phase and uses this to control the output voltage. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-68630 A Summary of the Invention [Problem to be solved by the invention]

[0005] Multiple distributed power sources may be connected in parallel and operated (parallel operation). In this case, appropriate control of the independent operation is required depending on the number, rated capacity, or type of the distributed power sources. However, in a system in which one of the multiple distributed power sources operates as a voltage source and the others operate as current sources, only the distributed power source that acts as a voltage source immediately follows the load, so a load that exceeds the capacity of the distributed power source that acts as a voltage source cannot be connected. To address this problem, the distributed power source that acts as a current source must also follow the load at the same processing speed as the distributed power source that acts as a voltage source, and the distributed power source that acts as a current source is required to perform extremely high-speed calculations and control. In addition, in a system in which all of the multiple distributed power sources operate as voltage sources, potential differences and phase differences occur due to communication during synchronization between the multiple distributed power sources and measurement errors in each distributed power source, and these potential differences and phase differences become problems. For example, not only does an inrush current occur when the power source is turned on, but unintended leakage of active power and reactive power occurs between the multiple distributed power sources.

[0006] The present disclosure has been made in consideration of the above circumstances, and has an object to provide a power system that can effectively control the isolated operation when multiple distributed power sources are operated in parallel. Also, a monitoring device and a program for realizing the power system that effectively controls the isolated operation are provided. [Means for solving the problem]

[0007] A monitoring device provided by a first aspect of the present disclosure includes a receiving unit that receives an active power output value and a reactive power output value from each of a plurality of inverter devices, a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices, a first calculation unit to which the active power target value and the active power output value are input and that calculates a voltage phase command value for each of the plurality of inverter devices, a second calculation unit to which the reactive power target value and the reactive power output value are input and that calculates a voltage amplitude command value for each of the plurality of inverter devices, and a setting unit that sets an active power target value and a reactive power output value for each of the plurality of inverter devices. a transmission unit that transmits each of the plurality of inverter devices a voltage amplitude command value to a corresponding inverter device, a distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices, and a total value calculation unit that calculates an active power total value that is a total value of each active power output value of the plurality of inverter devices and a reactive power total value that is a total value of each reactive power output value of the plurality of inverter devices, wherein the setting unit calculates the active power target value for each of the plurality of inverter devices from the active power total value and the distribution ratio of each inverter device, and calculates the reactive power target value from the reactive power total value and the distribution ratio of each inverter device.

[0008] In a preferred embodiment of the monitoring device, the distribution ratio calculation unit calculates the reciprocal of the number of the plurality of inverter devices as the distribution ratio for each inverter device.

[0009] In a preferred embodiment of the monitoring device, the distribution ratio calculation unit calculates a ratio of the rated capacity of each of the inverter devices to a total value of the rated capacities of the plurality of inverter devices as the distribution ratio of that inverter device.

[0010] In a preferred embodiment of the monitoring device, the multiple inverter devices include multiple battery control devices each connected to a storage battery, and the distribution rate calculation unit calculates, for each of the multiple battery control devices, a ratio of the rated capacity of each of the multiple storage batteries to a total value of the rated capacities of the multiple storage batteries as a distribution rate of the storage battery control device to which the storage battery is connected, the receiving unit receives the charging rates of the storage batteries from each of the multiple battery control devices, and the setting unit corrects the active power target value based on the difference between the average charging rate of each of the storage batteries and each charging rate.

[0011] A power system provided by a second aspect of the present disclosure includes the monitoring device provided by the first aspect and the plurality of inverter devices, each of the plurality of inverter devices includes a control unit that controls an output voltage and a measurement unit that measures the active power output value and the reactive power output value, and the control unit controls the output voltage based on the voltage phase command value and the voltage amplitude command value.

[0012] A program provided by a third aspect of the present disclosure includes a computer including a receiving unit that receives an active power output value and a reactive power output value from each of a plurality of inverter devices, a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices, a first calculation unit to which the active power target value and the active power output value are input and that calculates a voltage phase command value for each of the plurality of inverter devices, a second calculation unit to which the reactive power target value and the reactive power output value are input and that calculates a voltage amplitude command value for each of the plurality of inverter devices, and a setting unit that sets an active power target value and a reactive power output value for each of the plurality of inverter devices. The setting unit functions as a transmitting unit that transmits the voltage amplitude command value to a corresponding inverter device, a distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices, and a total value calculation unit that calculates an active power total value that is the total value of each active power output value of the plurality of inverter devices and a reactive power total value that is the total value of each reactive power output value of the plurality of inverter devices, and the setting unit calculates the active power target value for each of the plurality of inverter devices from the active power total value and the distribution ratio of each inverter device, and calculates the reactive power target value from the reactive power total value and the distribution ratio of each inverter device. Effect of the Invention

[0013] According to the monitoring device of the present disclosure, when multiple inverter devices are operated in parallel, the operation of each inverter device can be controlled so that the output power (active power and reactive power) of each inverter device is appropriately distributed. This enables the monitoring device to appropriately control the independent operation according to the number of inverter devices, the rated capacity, or the type of DC power source, and thus allows the independent operation to be well controlled.

[0014] Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0015] [Figure 1] 1 is a diagram illustrating an example of the overall configuration of a power system according to a first embodiment. [Diagram 2] 1 is a functional block diagram of a power system according to a first embodiment. [Diagram 3] 4 is a flowchart showing a process of the monitoring device according to the first embodiment. [Figure 4] FIG. 11 is a functional block diagram of a power system according to a second embodiment. [Diagram 5] FIG. 11 is a diagram illustrating an example of the overall configuration of a power system according to a third embodiment. [Figure 6] FIG. 11 is a functional block diagram of a power system according to a third embodiment. [Figure 7] FIG. 13 is a diagram showing a simulation result of the power system according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Preferred embodiments of a monitoring device, a power system, and a program according to the present disclosure will be described below with reference to the drawings. In the following, identical or similar components are designated by the same reference numerals and duplicated descriptions will be omitted.

[0017] Fig. 1 shows an example of the overall configuration of a power system S1 according to the first embodiment. As shown in the figure, the power system S1 includes a plurality of inverter devices 1 and a monitoring device 2. In this embodiment, the power system S1 includes n (n is a natural number) inverter devices 1.

[0018] In the power system S1, a plurality of inverter devices 1 are connected in parallel to each other. The power system S1 performs independent operation (non-grid operation) when disconnected from the power grid K. In the power system S1, the plurality of inverter devices 1 cooperate with the monitoring device 2 to control the independent operation. During the independent operation, power is supplied from the plurality of inverter devices 1 to the load L. In the power system S1, each of the plurality of inverter devices 1 and the monitoring device 2 can communicate with each other. The communication between each inverter device 1 and the monitoring device 2 may be wireless or wired.

[0019] As shown in Fig. 1, a DC power supply 19 is connected to each of the multiple inverter devices 1. The DC power supply 19 is, for example, a generator that uses renewable energy such as a solar cell, a generator that uses an internal combustion engine or an external combustion engine, or a storage battery. Each inverter device 1 appropriately converts and outputs the power generated by the DC power supply 19 or the power stored in the DC power supply 19. An AC power supply may be connected to each inverter device 1 via a rectifier circuit instead of the DC power supply 19.

[0020] FIG. 2 is a diagram for explaining the details of the power system S1, and is a functional block diagram relating to the independent operation control performed by the power system S1.

[0021] Each of the multiple inverter devices 1 controls output power based on a control command received from the monitoring device 2. Each inverter device 1 is a voltage type inverter that operates as a voltage source, and controls the output power by controlling the output voltage. In this embodiment, the multiple inverter devices 1 have the same rated capacity (rated output). As shown in FIG. 2, each of the multiple inverter devices 1 includes a measurement unit 11, a transmission unit 12, a reception unit 13, and a control unit 14.

[0022] The measuring unit 11 measures the active power output value and reactive power output value of its own device. Hereinafter, the active power output value of the i-th inverter device 1 is referred to as the active power output value Pout_i, and the reactive power output value of the i-th inverter device 1 is referred to as the reactive power output value Qout_i, where i is a natural number equal to or less than n. The measuring unit 11 is disposed at the output end (the upper end in FIG. 1) of each inverter device 1.

[0023] The transmitter 12 transmits information about its own device to the monitoring device 2. The information transmitted by the transmitter 12 includes, for example, the active power output value Pout_i and the reactive power output value Qout_i measured by the measurement unit 11. The transmitter 12 transmits the information about its own device at predetermined intervals.

[0024] The receiver 13 receives the control command transmitted from the monitoring device 2. The receiver 13 outputs the received control command to the controller 14. The control command includes a voltage phase command value and a voltage amplitude command value. The voltage phase command value is a target value or an adjustment value for the phase of the output voltage, and the voltage amplitude command value is a target value or an adjustment value for the amplitude of the output voltage.

[0025] The control unit 14 controls the output voltage of the device itself based on the control command received by the receiving unit 13. As shown in FIG. 2, the control unit 14 includes a phase control unit 141 and an amplitude control unit 142. The phase control unit 141 controls the phase of the output voltage based on a voltage phase command value. When the voltage phase command value is a target value of the phase of the output voltage, the phase control unit 141 controls the phase of the output voltage to the voltage phase command value. When the voltage phase command value is an adjustment value of the phase of the output voltage, the phase control unit 141 adjusts the phase of the output voltage from the current value by the voltage phase command value. The amplitude control unit 142 controls the amplitude of the output voltage based on the voltage amplitude command value. When the voltage amplitude command value is a target value of the amplitude of the output voltage, the amplitude control unit 142 controls the amplitude of the output voltage to the voltage amplitude command value. When the voltage amplitude command value is an adjustment value of the amplitude of the output voltage, the amplitude control unit 142 adjusts the amplitude of the output voltage from the current value by the voltage amplitude command value.

[0026] The monitoring device 2 acquires information from each inverter device 1, and generates a control command (a voltage phase command value and a voltage amplitude command value) for each inverter device 1 based on the acquired information. The monitoring device 2 transmits the generated control command to each inverter device 1. As shown in FIG. 2, the monitoring device 2 includes a receiving unit 21, a total value calculating unit 22, a distribution ratio calculating unit 23A, a setting unit 24A, a first calculating unit 25, a second calculating unit 26, and a transmitting unit 27.

[0027] The receiving unit 21 receives information transmitted from each inverter device 1. The information received by the receiving unit 21 includes the active power output value Pout_i and the reactive power output value Qout_i of each inverter device 1. The receiving unit 21 outputs the received active power output value Pout_i and reactive power output value Qout_i to the total value calculation unit 22. In addition, the receiving unit 21 outputs the received active power output value Pout_i to the first calculation unit 25, and outputs the received reactive power output value Qout_i to the second calculation unit 26.

[0028] The sum calculation unit 22 calculates an active power sum Psum by integrating the active power output values ​​Pout_i of each inverter device 1. The sum calculation unit 22 also calculates a reactive power sum Qsum by integrating the reactive power output values ​​Qout_i of each inverter device 1. The sum calculation unit 22 outputs the calculated active power sum Psum and reactive power sum Qsum to the setting unit 24A.

[0029] The distribution ratio calculation unit 23A calculates the distribution ratio for each inverter device 1. The distribution ratio calculation unit 23A calculates the reciprocal 1 / n of the number n of the inverter devices 1 as the distribution ratio for each inverter device 1. Information on the number n of the inverter devices 1 may be stored in advance in the monitoring device 2 (distribution ratio calculation unit 23A) by a user input, or the monitoring device 2 may count the inverter devices 1 to be controlled when the operation of the power system S1 starts. The distribution ratio calculation unit 23A outputs the calculated distribution ratio to the setting unit 24A.

[0030] The setting unit 24A sets a target value of the active power output value and a target value of the reactive power output value for each inverter device 1. Hereinafter, the target value of the active power output value of the i-th inverter device 1 is referred to as an active power target value Pref_i, and the target value of the reactive power output value of the i-th inverter device 1 is referred to as a reactive power target value Qref_i. The active power target value Pref_i is a value obtained by distributing the active power total value Psum to each of the multiple inverter devices 1. The reactive power target value Qref_i is a value obtained by distributing the reactive power total value Qsum to each of the multiple inverter devices 1.

[0031] 2, the setting unit 24A includes two multipliers 241P and 241Q. An active power target value Pref_i of each inverter device 1 is calculated by the multiplier 241P, and a reactive power target value Qref_i of each inverter device 1 is calculated by the multiplier 241Q.

[0032] The multiplier 241P receives the active power sum Psum and the distribution rate for each inverter device 1, and multiplies the active power sum Psum by the distribution rate. The setting unit 24A sets the multiplication result by the multiplier 241P as the active power target value Pref_i. In this embodiment, since the distribution rate is the reciprocal of the number of the multiple inverter devices 1, the multiplication result by the multiplier 241P is a value obtained by dividing the active power sum Psum by the number n of the multiple inverter devices 1. In other words, the active power target value Pref_i is the average value of the active power output values ​​Pout_i, and is a value obtained by equally distributing the active power sum Psum among the multiple inverter devices 1.

[0033] The multiplier 241Q receives the reactive power sum Qsum and the distribution ratio for each inverter device 1, and multiplies the reactive power sum Qsum by the distribution ratio. The setting unit 24A sets the multiplication result by the multiplier 241Q as the reactive power target value Qref_i. In this embodiment, since the distribution ratio is the reciprocal of the number of the multiple inverter devices 1, the multiplication result by the multiplier 241Q is a value obtained by dividing the reactive power sum Qsum by the number n of the multiple inverter devices 1. In other words, the reactive power target value Qref_i is an average value of the reactive power output values ​​Qout_i, and is a value obtained by equally distributing the reactive power sum Qsum among the multiple inverter devices 1.

[0034] The first calculation unit 25 calculates the voltage phase command value of each inverter device 1. The first calculation unit 25 receives an active power target value Pref_i and an active power output value Pout_i of the i-th inverter device 1 to be calculated. The first calculation unit 25 calculates a voltage phase command value of the inverter device 1 to be calculated from the input active power target value Pref_i and active power output value Pout_i. The first calculation unit 25 performs this calculation for each of the multiple inverter devices 1. The first calculation unit 25 outputs the calculated voltage phase command value of each inverter device 1 to the transmission unit 27. As shown in FIG. 2, the first calculation unit 25 includes a differentiator 251 and a controller 252.

[0035] The difference calculator 251 receives the active power target value Pref_i and the active power output value Pout_i of the i-th inverter device 1 to be calculated, and calculates the deviation ΔPi (=Pout_i-Pref_i) between the active power output value Pout_i and the active power target value Pref_i. The difference calculator 251 calculates the deviation ΔPi for each of the multiple inverter devices 1. The controller 252 calculates a voltage phase command value for the i-th inverter device 1 to be calculated, for making the deviation ΔPi zero. The controller 252 performs, for example, proportional control (P control). The control method of the controller 252 is not limited to proportional control, and for example, PI control or PID control may be performed instead of proportional control. The controller 252 calculates the voltage phase command value for each of the multiple inverter devices 1.

[0036] The second calculation unit 26 calculates the voltage amplitude command value of each inverter device 1. The second calculation unit 26 receives the reactive power target value Qref_i and the reactive power output value Qout_i of the i-th inverter device 1 to be calculated. The second calculation unit 26 calculates the voltage amplitude command value of the inverter device 1 to be calculated from the input reactive power target value Qref_i and the reactive power output value Qout_i. The second calculation unit 26 performs this calculation for each of the multiple inverter devices 1. The second calculation unit 26 outputs the calculated voltage amplitude command value of each inverter device 1 to the transmission unit 27. As shown in FIG. 2, the second calculation unit 26 includes a difference calculator 261 and a controller 262.

[0037] The difference calculator 261 receives the reactive power target value Qref_i and the reactive power output value Qout_i of the i-th inverter device 1 to be calculated, and calculates the deviation ΔQi (=Qout_i-Qref_i) between the reactive power output value Qout_i and the reactive power target value Qref_i. The difference calculator 261 calculates the deviation ΔQi for each of the multiple inverter devices 1. The controller 262 calculates a voltage amplitude command value for the i-th inverter device 1 to be calculated, for making the deviation ΔQi zero. The controller 262 performs, for example, proportional control. The control method of the controller 262 is not limited to proportional control, and may perform, for example, PI control or PID control instead of proportional control. The controller 262 calculates the voltage amplitude command value for each of the multiple inverter devices 1.

[0038] The transmitting unit 27 transmits a control command including a voltage phase command value and a voltage amplitude command value for each inverter device 1 to each inverter device 1. The voltage phase command value is input from the first calculating unit 25, and the voltage amplitude command value is input from the second calculating unit 26.

[0039] 3 is a flowchart showing the process performed by the monitoring device 2 during the isolated operation control of the power system S1. The process is started when the monitoring device 2 is started.

[0040] When the active power output value Pout_i and the reactive power output value Qout_i are transmitted from each inverter device 1, the receiving unit 21 receives the active power output value Pout_i and the reactive power output value Qout_i transmitted from each inverter device 1 (S101: YES). If the receiving unit 21 does not receive the active power output value Pout_i and the reactive power output value Qout_i in step S101 (S101: NO), the receiving unit 21 waits until it receives the active power output value Pout_i and the reactive power output value Qout_i.

[0041] Next, the total value calculation unit 22 calculates the active power total value Psum and the reactive power total value Qsum (S102). Next, the distribution ratio calculation unit 23A calculates the distribution ratio for each inverter device 1 (S103). In the example shown in Fig. 3, step S103 is performed every time the receiving unit 21 receives the active power output value Pout_i and the reactive power output value Qout_i, but it may be configured to be performed only when the monitoring device 2 is started up.

[0042] Next, the setting unit 24A sets an active power target value Pref_i and a reactive power target value Qref_i of each inverter device 1 (S104). Next, the first calculation unit 25 calculates a voltage phase command value of each inverter device 1, and the second calculation unit 26 calculates a voltage amplitude command value of each inverter device 1 (S105). Next, the transmission unit 27 transmits a control command including the voltage phase command value and the voltage amplitude command value to each inverter device 1 (S106).

[0043] Thereafter, the monitoring device 2 performs an end determination (S107), and if it determines that the process has not ended (S107: NO), the process returns to step S101 and repeats the processes from step S101 to step S106 until it determines that the process has ended. On the other hand, if it determines that the process has ended by the end determination in step S107 (S107: YES), the process ends. In step S107, it is determined that the process has ended when, for example, the power supply of the monitoring device 2 is turned off or the user operates to stop the process.

[0044] Each unit of the monitoring device 2 is realized, for example, as a digital circuit, but may also be realized as an analog circuit. Furthermore, the processes performed by each unit of the monitoring device 2 (see FIG. 3) may be designed as a program, and a computer may function as the monitoring device 2 by executing the program. Furthermore, the program may be recorded on a storage medium and read by a computer.

[0045] The functions and effects of the power system S1 are as follows.

[0046] In the power system S1, the monitoring device 2 uses the distribution ratio calculation unit 23A to calculate the reciprocal 1 / n of the number n of the inverter devices 1 as the distribution ratio of each inverter device 1. Then, the setting unit 24A distributes the active power sum Psum according to the distribution ratio of each inverter device 1 and sets it as the active power target value. Also, the setting unit 24A distributes the reactive power sum Qsum according to the distribution ratio of each inverter device 1 and sets it as the reactive power target value. After that, the first calculation unit 25 calculates a voltage phase command value so that the active power output value of each inverter device 1 becomes the active power target value, and the second calculation unit 26 calculates a voltage amplitude command value so that the reactive power output value of each inverter device 1 becomes the reactive power output value. Each inverter device 1 controls its output voltage according to the voltage phase command value and the voltage amplitude command value calculated by the monitoring device 2. According to this configuration, the output power (active power and reactive power) of each inverter device 1 is equalized among the multiple inverter devices 1, and the monitoring device 2 can control all the inverter devices 1 to operate in the same way. As a result, even if each inverter device 1 is configured with a voltage-type inverter, the power system S1 can suppress the phase difference and potential difference (amplitude difference) between the multiple inverter devices 1. The leakage of active power occurs due to a phase shift of the output voltage of the inverter device 1, and the leakage of reactive power occurs due to a phase shift of the output voltage of the inverter device 1. In other words, the power system S1 can suppress the potential difference and phase difference between the multiple inverter devices 1, and therefore can suppress unintended leakage of power in the multiple inverter devices 1. Therefore, when the multiple inverter devices 1 are operated in parallel, the power system S1 can perform an appropriate independent operation according to the number of the inverter devices 1. Furthermore, when the multiple inverter devices 1 are operated in parallel, the monitoring device 2 can control the appropriate independent operation according to the number of the inverter devices 1, and the independent operation of the power system S1 becomes good.

[0047] A power system S2 according to the second embodiment will be described. FIG. 4 is a functional block diagram relating to the independent operation control performed by the power system S2. The overall configuration of the power system S2 is the same as the overall configuration of the power system S1 (see FIG. 1). The processing performed by the monitoring device 2 in the independent operation control of the power system S2 is similar to the processing performed by the monitoring device 2 of the power system S1 (see FIG. 3). However, unlike the power system S1, in the power system S2, at least two of the multiple inverter devices 1 have different rated capacities. In other words, the multiple inverter devices 1 include those with different rated capacities.

[0048] As shown in FIG. 4, power system S2 differs from power system S1 in that monitoring device 2 includes distribution rate calculation unit 23B instead of distribution rate calculation unit 23A.

[0049] As shown in FIG. 4, the distribution ratio calculation unit 23B includes two calculators 231 and 232, and calculates the distribution ratio of the second embodiment by the two calculators 231 and 232. The calculator 231 integrates the rated capacities of the multiple inverter devices 1 to calculate a total rated capacity value. The calculator 232 calculates the distribution ratio of the inverter device 1 to be calculated by dividing the rated capacity of the inverter device 1 to be calculated by the total rated capacity value. Therefore, the distribution ratio in the second embodiment is the ratio of the rated capacity of each inverter device 1 to the total value (total rated capacity value) of the rated capacities of the multiple inverter devices 1. The calculation of the distribution ratio by the calculator 232 is performed for each inverter device 1. The rated capacity of each inverter device 1 may be stored in advance in the monitoring device 2 (distribution ratio calculation unit 23B) by a user input, or may be acquired from each inverter device 1 by the monitoring device 2 when the operation of the power system S2 starts, or may be received from each inverter device 1 by the monitoring device 2 simultaneously with the active power output value and the reactive power output value. The distribution ratio calculation unit 23B outputs the calculated distribution ratio of each inverter device 1 to the setting unit 24A.

[0050] In the power system S2, the setting unit 24A sets the active power target value Pref_i to a value obtained by distributing the active power sum Psum in accordance with the distribution ratio of each inverter device 1 input from the distribution ratio calculation unit 23B. In this configuration, the larger the rated capacity of the inverter device 1, the larger the active power target value Pref_i. Also, in the power system S2, the setting unit 24A sets the reactive power target value Qref_i to a value obtained by distributing the reactive power sum Qsum in accordance with the distribution ratio of each inverter device 1 input from the distribution ratio calculation unit 23B. In this configuration, the larger the rated capacity of the inverter device 1, the larger the reactive power target value Qref_i.

[0051] In the power system S2, the monitoring device 2 calculates, as a distribution ratio, the ratio of the rated capacity of each inverter device 1 to the total value of the rated capacity of each of the multiple inverter devices 1 by the distribution ratio calculation unit 23B. Then, the setting unit 24A distributes the active power total value Psum according to the distribution ratio of each inverter device 1 and sets it as the active power target value. Also, the setting unit 24A distributes the reactive power total value Qsum according to the distribution ratio of each inverter device 1 and sets it as the reactive power target value. With this configuration, the monitoring device 2 can perform output distribution according to the rated capacity of each of the multiple inverter devices 1 having different rated capacities. Therefore, when the multiple inverter devices 1 are operated in parallel, the power system S2 can perform appropriate independent operation according to the number of inverter devices 1 and the rated capacity of each inverter device 1. Also, when the multiple inverter devices 1 are operated in parallel, the monitoring device 2 can control appropriate independent operation according to the number of inverter devices 1 and the rated capacity of each inverter device 1, and the independent operation of the power system S2 becomes good.

[0052] In the second embodiment, an example has been shown in which at least two of the multiple inverter devices 1 have different rated capacities, but the multiple inverter devices 1 may have the same rated capacity. In this case, in the power system S2, the distribution ratio calculated by the distribution ratio calculation unit 23B is the same as the distribution ratio calculated by the distribution ratio calculation unit 23A, so that the output power (active power and reactive power) of each inverter device 1 is equalized among the multiple inverter devices 1, and the same effect as that of the power system S1 is achieved.

[0053] A power system S3 according to the third embodiment will be described with reference to Fig. 5 and Fig. 6. Fig. 5 shows an example of the overall configuration of the power system S3. Fig. 6 is a functional block diagram relating to the independent operation control performed by the power system S3. Note that the processing performed by the monitoring device 2 in the independent operation control of the power system S3 is similar to the processing performed by each monitoring device 2 of the power system S1 (see Fig. 3).

[0054] In the power system S3, as shown in Fig. 5 and Fig. 6, the inverter devices 1 include a plurality of storage battery control devices 1A. The DC power source 19 connected to each storage battery control device 1A is a storage battery 19A. In this embodiment, the storage battery control devices 1A have the same rated capacity, whereas the storage batteries 19A have different rated capacities. Hereinafter, the rated capacity of the storage battery 19A is referred to as "storage battery capacity." In the example shown in Fig. 5 and Fig. 6, all of the inverter devices 1 are storage battery control devices 1A.

[0055] Each battery control device 1A has the same configuration as the inverter device 1. However, as shown in Fig. 6, each battery control device 1A further includes a monitoring unit 15. The monitoring unit 15 monitors the state of charge (SoC) of the connected battery 19A. Each battery control device 1A transmits information on the state of charge of the battery 19A from the transmission unit 12 to the monitoring device 2 together with the active power output value Pout_i and the reactive power output value Qout_i.

[0056] 6, power system S3 is different from power systems S1 and S2 in the configuration of monitoring device 2. Specifically, monitoring device 2 of power system S3 is different from monitoring device 2 of power systems S1 and S2 in that it has distribution rate calculation unit 23C instead of distribution rate calculation units 23A and 23B, and has setting unit 24B instead of setting unit 24A.

[0057] The distribution ratio calculation unit 23C calculates a first distribution ratio and a second distribution ratio for each battery control device 1A. As shown in Fig. 6, the distribution ratio calculation unit 23C includes calculators 231, 232, 233, and 234, and calculates the first distribution ratio using the calculators 233 and 234, and calculates the second distribution ratio using the calculators 231 and 232.

[0058] The calculator 233 integrates the rated capacities of the multiple storage batteries 19A to calculate the total battery capacity value. The calculator 234 calculates the first distribution ratio of the storage battery control device 1A to be calculated by dividing the storage battery capacity of the storage battery 19A connected to the storage battery control device 1A to be calculated by the total battery capacity value. Thus, the first distribution ratio is the ratio of the storage battery capacity of each storage battery 19A to the total value (total battery capacity value) of the storage batteries 19A. The calculator 234 calculates the first distribution ratio for each storage battery control device 1A. The storage battery capacity of each storage battery 19A may be stored in advance in the monitoring device 2 (distribution ratio calculation unit 23C) by a user input, or may be acquired by the monitoring device 2 from each storage battery control device 1A when the operation of the power system S3 is started, or may be received by the monitoring device 2 from each storage battery control device 1A simultaneously with the active power output value and the reactive power output value. The distribution ratio calculation unit 23C outputs the calculated first distribution ratio of each battery control device 1A to the setting unit 24B (multiplier 241P).

[0059] The calculators 231 and 232 calculate the second distribution ratio by the same calculation as in the second embodiment. That is, the second distribution ratio is the ratio of the rated capacity of each storage battery control device 1A to the total value of the rated capacities of the multiple storage battery control devices 1A (total rated capacity value). The second distribution ratio may be the same as the distribution ratio in the first embodiment. That is, the distribution ratio calculation unit 23C calculates the reciprocal of the number of storage battery control devices 1A as the second distribution ratio. The distribution ratio calculation unit 23C outputs the calculated second distribution ratio of each storage battery control device 1A to the setting unit 24B (multiplier 241Q).

[0060] The setting unit 24B sets the value obtained by distributing the total active power value according to the first distribution ratio of each battery control device 1A as the active power target value. After that, this active power target value is corrected by the difference between the average value of the charging rates of each battery 19A and each charging rate, and outputs it to the first calculation unit 25. Therefore, in this embodiment, the first calculation unit 25 calculates a voltage phase command value using the corrected active power target value. In addition, the setting unit 24B sets the value obtained by distributing the total reactive power value according to the second distribution ratio of each battery control device 1A as the reactive power target value. Output distribution according to the battery capacity (distribution according to the first distribution ratio) and correction according to the charging rate need only be performed on the active power that affects the charging and discharging of the battery 19A, and output distribution according to the rated capacity of the battery control device 1A (distribution according to the second distribution ratio) is performed on the reactive power.

[0061] 6, setting unit 24B includes two multipliers 241P, 241Q, as well as a calculator 242P and an adder 243P. The active power target value of each battery control device 1A is calculated by multiplier 241P and corrected by calculator 242P and adder 243P. In addition, the reactive power target value of each battery control device 1A is calculated by multiplier 241Q.

[0062] The multiplier 241P in this embodiment multiplies the active power total value Psum input from the total value calculation unit 22 by the first distribution ratio input from the distribution ratio calculation unit 23C for each storage battery control device 1A. The multiplier 241P outputs this multiplication result (provisional active power target value Pref_i) to the calculator 242P. Moreover, the multiplier 241Q in this embodiment multiplies the reactive power total value Qsum input from the total value calculation unit 22 by the second distribution ratio input from the distribution ratio calculation unit 23C for each storage battery control device 1A. The multiplier 241Q outputs this multiplication result (reactive power target value Qref_i) to the second calculation unit 26.

[0063] The calculator 242P obtains an average value of the charging rates of the storage batteries 19A, and calculates a difference ΔSoCi between this average charging rate and the charging rate of the storage battery 19A connected to the storage battery control device 1A that is the calculation target. The charging rates of the storage batteries 19A are received from the storage battery control device 1A by the receiver 21, and input from the receiver 21 to the calculator 242P. The calculator 242P includes a controller (not shown), which calculates a correction value for the storage battery control device 1A that is the calculation target to make the difference ΔSoCi zero. The controller performs proportional control, for example. The control method of the controller is not limited to proportional control, and may perform PI control or PID control, for example, instead of proportional control.

[0064] The adder 243P receives the multiplication result (active power target value) of the multiplier 241P and the correction value calculated by the calculator 242P. The adder 243P corrects the active power target value by adding the correction value to the multiplication result (active power target value).

[0065] FIG. 7 shows the results of simulating independent operation control using a model power system S3 equipped with three battery control devices 1A. FIG. 7(a) shows the change over time in the active power output value of each battery control device 1A. In FIG. 7(a), the vertical axis represents the active power output value of each battery control device 1A, and the horizontal axis represents elapsed time. FIG. 7(b) shows the change over time in the charging rate of the battery 19A connected to each battery control device 1A. In FIG. 7(b), the vertical axis represents the charging rate of each battery 19A, and the horizontal axis represents elapsed time.

[0066] In FIG. 7, the active power output value of the first battery control device 1A is indicated by Pout_1, and the charging rate of the battery 19A connected to this battery control device 1A is indicated by SoC_1. Similarly, the active power output value of the second battery control device 1A is indicated by Pout_2, and the charging rate of the battery 19A connected to this battery control device 1A is indicated by SoC_2, and the active power output value of the third battery control device 1A is indicated by Pout_3, and the charging rate of the battery 19A connected to this battery control device 1A is indicated by SoC_3. The sum of the active power output values ​​of the three battery control devices 1A is indicated by Psum, and the average charging rate of the three batteries 19A is indicated by SoC_avg. In FIG. 7(b), the charging rate SoC_3 and the average charging rate SoC_avg are approximately overlapped.

[0067] The three storage battery control devices 1A have the same rated capacity, but the storage battery capacity and the charging rate at the start of the simulation of each connected storage battery 19A (hereinafter referred to as "starting charging rate") are different. Specifically, the storage battery 19A connected to the first storage battery control device 1A has a storage battery capacity of 50 kWh and a starting charging rate of 40%. The storage battery 19A connected to the second storage battery control device 1A has a storage battery capacity of 100 kWh and a starting charging rate of 30%. The storage battery 19A connected to the third storage battery control device 1A has a storage battery capacity of 200 kWh and a starting charging rate of 35%. In this case, the first distribution rate calculated by the distribution rate calculation unit 23C is as follows. The first distribution ratio for the first battery control device 1A is 1 / 7 (=50 / (50+100+200)), the first distribution ratio for the second battery control device 1A is 2 / 7 (=100 / (50+100+200)), and the first distribution ratio for the third battery control device 1A is 4 / 7 (=200 / (50+100+200)).

[0068] At the start of the simulation, the first battery control device 1A has an active power output value Pout_1 of approximately 55 kW, the second battery control device 1A has an active power output value Pout_2 of approximately -40 kW, and the third battery control device 1A has an active power output value Pout_3 of approximately 20 kW. The second battery control device 1A has an active power output value Pout_2 that is a negative value, and is in a state in which the storage battery 19A is being charged. Therefore, the active power total value Psum of the three battery control devices 1A at the start of the simulation is 35 kW (= 55 - 40 + 20). At this time, the multiplication result of the multiplier 241P (setting unit 24B), which is the active power target value (provisional value) for the first battery control device 1A, is calculated from the product ((1 / 7) × (35)) of the first distribution ratio and the active power total value Psum, and is 5 kW. The active power target values ​​(provisional values) for the second and third battery control devices 1A are calculated in the same manner and are 10 kW and 20 kW, respectively. Note that these values ​​are the active power target values ​​before the calculation unit 242P and the adder 243P perform correction for the difference in the charging rates, and therefore are provisional active power target values.

[0069] From the simulation results shown in Fig. 7, as shown in Fig. 7(a), even if the output of each battery control device 1A is changed according to the battery capacity of each battery 19A, the total active power value Psum of the three battery control devices 1A does not change and remains constant. Also, as shown in Fig. 7(b), at the start of the simulation, the charging rates of the batteries 19A were different, but as time passed, they converged to the same value. Then, when the charging rates SoC_1, SoC_2, and SoC_3 of the batteries 19A converged to the same value, no correction was made by the calculator 242P and the adder 243P, and the active power output values ​​Pout_1, Pout_2, and Pout_3 of the battery control devices 1A became the above-mentioned active power target values ​​of 5kW, 10kW, and 20kW, respectively.

[0070] In the power system S3, the monitoring device 2 uses the distribution ratio calculation unit 23C to calculate the ratio of the rated capacity of each of the storage batteries 19A to the total value of the rated capacities of the multiple storage batteries 19A as the first distribution ratio of the storage battery control device 1A to which the storage battery 19A is connected. Then, the setting unit 24B distributes the total of the active power output values ​​of the multiple storage battery control devices 1A (active power total value Psum) according to the first distribution ratio of each storage battery control device 1A and sets it as the active power target value. With this configuration, the monitoring device 2 can perform output distribution according to the storage battery capacity (rated capacity of the storage battery 19A) for the storage batteries 19A having different storage battery capacities. Therefore, when multiple storage battery control devices 1A (inverter devices 1 to which storage batteries are connected) are operated in parallel, the power system S3 can perform appropriate independent operation according to the number of storage battery control devices 1A and the rated capacity (storage battery capacity) of each storage battery 19A. In addition, when multiple battery control devices 1A (inverter devices 1 to which storage batteries are connected) are operated in parallel, the monitoring device 2 is able to control appropriate independent operation according to the number of battery control devices 1A and the rated capacity (storage battery capacity) of each storage battery 19A, resulting in good independent operation of the power system S3.

[0071] In the power system S3, the setting unit 24B of the monitoring device 2 corrects the active power target value Pref_i based on the difference between the average value of the charging rates of the storage batteries 19A and the charging rates. With this configuration, when there is a difference in the charging rates of the storage batteries 19A, the charging rates of the storage batteries 19A are averaged, and bias in the charging rates can be suppressed. In other words, in the power system S3, control is performed to intentionally circulate power between multiple inverter devices 1 (storage battery control devices 1A), making it possible to average the charging rates of the storage batteries 19A.

[0072] The monitoring device, the power system, and the program according to the present disclosure are not limited to the above-described embodiment. The specific configurations of the components of the monitoring device, the power system, and the program according to the present disclosure can be freely designed in various ways. [Explanation of symbols]

[0073] S1 to S3: power system, 1: inverter device, 1A: storage battery control device, 11: measurement unit, 12: transmission unit, 13: reception unit, 14: control unit, 19: DC power source, 19A: storage battery, 2: monitoring device, 21: reception unit, 22: total value calculation unit, 23A to 23C: distribution rate calculation unit, 24A, 24B: setting unit, 25: first calculation unit, 26: second calculation unit, 27: transmission unit

Claims

1. a receiving unit that receives an active power output value and a reactive power output value from each of the plurality of inverter devices; a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices; a first calculation unit that receives the active power target value and the active power output value for each of the plurality of inverter devices, calculates a deviation between the active power target value and the active power output value, and calculates a voltage phase command value for making the deviation zero; a second calculation unit that receives the reactive power target value and the reactive power output value for each of the plurality of inverter devices, calculates a deviation between the reactive power target value and the reactive power output value, and calculates a voltage amplitude command value for making the deviation zero; a transmitter that transmits the voltage phase command value and the voltage amplitude command value to a corresponding inverter device; A distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices; a total value calculation unit that calculates an active power total value that is a total value of each active power output value of the plurality of inverter devices, and a reactive power total value that is a total value of each reactive power output value of the plurality of inverter devices; Equipped with The plurality of inverter devices are connected in parallel and supply power to a common load in a shared manner during an independent operation; the distribution ratio is a ratio at which the power supplied to the common load is shared among the plurality of inverter devices, the setting unit sets, for each of the plurality of inverter devices, a value obtained by distributing the total active power value in accordance with a distribution ratio of the corresponding inverter device as the active power target value, and sets, for each of the plurality of inverter devices, a value obtained by distributing the total reactive power value in accordance with the distribution ratio of the corresponding inverter device as the reactive power target value, the distribution ratio calculation unit calculates an inverse number of the plurality of inverter devices as a distribution ratio for each of the inverter devices; monitoring equipment.

2. a receiving unit that receives an active power output value and a reactive power output value from each of the plurality of inverter devices; a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices; a first calculation unit that receives the active power target value and the active power output value for each of the plurality of inverter devices, calculates a deviation between the active power target value and the active power output value, and calculates a voltage phase command value for making the deviation zero; a second calculation unit that receives the reactive power target value and the reactive power output value for each of the plurality of inverter devices, calculates a deviation between the reactive power target value and the reactive power output value, and calculates a voltage amplitude command value for making the deviation zero; a transmitter that transmits the voltage phase command value and the voltage amplitude command value to a corresponding inverter device; A distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices; a total value calculation unit that calculates an active power total value that is a total value of each active power output value of the plurality of inverter devices, and a reactive power total value that is a total value of each reactive power output value of the plurality of inverter devices; Equipped with The plurality of inverter devices are connected in parallel and supply power to a common load in a shared manner during an independent operation; the distribution ratio is a ratio at which the power supplied to the common load is shared among the plurality of inverter devices, the setting unit sets, for each of the plurality of inverter devices, a value obtained by distributing the total active power value in accordance with a distribution ratio of the corresponding inverter device as the active power target value, and sets, for each of the plurality of inverter devices, a value obtained by distributing the total reactive power value in accordance with the distribution ratio of the corresponding inverter device as the reactive power target value, The distribution ratio calculation unit calculates a ratio of a rated capacity of each of the inverter devices to a total value of the rated capacities of the plurality of inverter devices as a distribution ratio of the inverter device.

3. a receiving unit that receives an active power output value and a reactive power output value from each of the plurality of inverter devices; a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices; a first calculation unit that receives the active power target value and the active power output value for each of the plurality of inverter devices, calculates a deviation between the active power target value and the active power output value, and calculates a voltage phase command value for making the deviation zero; a second calculation unit that receives the reactive power target value and the reactive power output value for each of the plurality of inverter devices, calculates a deviation between the reactive power target value and the reactive power output value, and calculates a voltage amplitude command value for making the deviation zero; a transmitter that transmits the voltage phase command value and the voltage amplitude command value to a corresponding inverter device; A distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices; a total value calculation unit that calculates an active power total value that is a total value of each active power output value of the plurality of inverter devices, and a reactive power total value that is a total value of each reactive power output value of the plurality of inverter devices; Equipped with The plurality of inverter devices are connected in parallel and supply power to a common load in a shared manner during an independent operation; the distribution ratio is a ratio at which the power supplied to the common load is shared among the plurality of inverter devices, the setting unit sets, for each of the plurality of inverter devices, a value obtained by distributing the total active power value in accordance with a distribution ratio of the corresponding inverter device as the active power target value, and sets, for each of the plurality of inverter devices, a value obtained by distributing the total reactive power value in accordance with the distribution ratio of the corresponding inverter device as the reactive power target value, The plurality of inverter devices include a plurality of storage battery control devices each connected to a storage battery, the distribution ratio calculation unit calculates, for each of the plurality of storage battery control devices, a ratio of a rated capacity of each of the plurality of storage batteries to a total value of each rated capacity of the plurality of storage batteries as a distribution ratio of the storage battery control device to which the storage battery is connected; the receiving unit receives the charging rates of the storage batteries from each of the plurality of storage battery control devices; The setting unit corrects the active power target value based on a difference between an average value of each charging rate of the storage battery and each charging rate. monitoring equipment.

4. A monitoring device according to any one of claims 1 to 3; The plurality of inverter devices; It is equipped with Each of the plurality of inverter devices includes a control unit that controls an output voltage and a measurement unit that measures the active power output value and the reactive power output value, The control unit controls the output voltage based on the voltage phase command value and the voltage amplitude command value. Power system.

5. Computer, a receiving unit that receives an active power output value and a reactive power output value from each of the plurality of inverter devices; a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices; a first calculation unit that receives the active power target value and the active power output value for each of the plurality of inverter devices, calculates a deviation between the active power target value and the active power output value, and calculates a voltage phase command value for making the deviation zero; a second calculation unit that receives the reactive power target value and the reactive power output value for each of the plurality of inverter devices, calculates a deviation between the reactive power target value and the reactive power output value, and calculates a voltage amplitude command value for making the deviation zero; a transmitter that transmits the voltage phase command value and the voltage amplitude command value to a corresponding inverter device; A distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices; a total value calculation unit that calculates an active power total value that is a total value of each active power output value of the plurality of inverter devices, and a reactive power total value that is a total value of each reactive power output value of the plurality of inverter devices; Function as a The plurality of inverter devices are connected in parallel and supply power to a common load in a shared manner during an independent operation; the distribution ratio is a ratio at which the power supplied to the common load is shared among the plurality of inverter devices, the setting unit sets, for each of the plurality of inverter devices, a value obtained by distributing the total active power value in accordance with a distribution ratio of the corresponding inverter device as the active power target value, and sets, for each of the plurality of inverter devices, a value obtained by distributing the total reactive power value in accordance with the distribution ratio of the corresponding inverter device as the reactive power target value, the distribution ratio calculation unit calculates an inverse number of the plurality of inverter devices as a distribution ratio for each of the inverter devices; program.

6. Computer, a receiving unit that receives an active power output value and a reactive power output value from each of the plurality of inverter devices; a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices; a first calculation unit that receives the active power target value and the active power output value for each of the plurality of inverter devices, calculates a deviation between the active power target value and the active power output value, and calculates a voltage phase command value for making the deviation zero; a second calculation unit that receives the reactive power target value and the reactive power output value for each of the plurality of inverter devices, calculates a deviation between the reactive power target value and the reactive power output value, and calculates a voltage amplitude command value for making the deviation zero; a transmitter that transmits the voltage phase command value and the voltage amplitude command value to a corresponding inverter device; A distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices; a total value calculation unit that calculates an active power total value that is a total value of each active power output value of the plurality of inverter devices, and a reactive power total value that is a total value of each reactive power output value of the plurality of inverter devices; Function as a The plurality of inverter devices are connected in parallel and supply power to a common load in a shared manner during an independent operation; the distribution ratio is a ratio at which the power supplied to the common load is shared among the plurality of inverter devices, the setting unit sets, for each of the plurality of inverter devices, a value obtained by distributing the total active power value in accordance with a distribution ratio of the corresponding inverter device as the active power target value, and sets, for each of the plurality of inverter devices, a value obtained by distributing the total reactive power value in accordance with the distribution ratio of the corresponding inverter device as the reactive power target value, the distribution ratio calculation unit calculates a ratio of a rated capacity of each of the inverter devices to a total value of the rated capacities of the plurality of inverter devices as a distribution ratio of the inverter device; program.

7. Computer, a receiving unit that receives an active power output value and a reactive power output value from each of the plurality of inverter devices; a setting unit that sets an active power target value and a reactive power target value for each of the plurality of inverter devices; a first calculation unit that receives the active power target value and the active power output value for each of the plurality of inverter devices, calculates a deviation between the active power target value and the active power output value, and calculates a voltage phase command value for making the deviation zero; a second calculation unit that receives the reactive power target value and the reactive power output value for each of the plurality of inverter devices, calculates a deviation between the reactive power target value and the reactive power output value, and calculates a voltage amplitude command value for making the deviation zero; a transmitter that transmits the voltage phase command value and the voltage amplitude command value to a corresponding inverter device; A distribution ratio calculation unit that calculates a distribution ratio for each of the plurality of inverter devices; a total value calculation unit that calculates an active power total value that is a total value of each active power output value of the plurality of inverter devices, and a reactive power total value that is a total value of each reactive power output value of the plurality of inverter devices; Function as a The plurality of inverter devices are connected in parallel and supply power to a common load in a shared manner during an independent operation; the distribution ratio is a ratio at which the power supplied to the common load is shared among the plurality of inverter devices, the setting unit sets, for each of the plurality of inverter devices, a value obtained by distributing the total active power value in accordance with a distribution ratio of the corresponding inverter device as the active power target value, and sets, for each of the plurality of inverter devices, a value obtained by distributing the total reactive power value in accordance with the distribution ratio of the corresponding inverter device as the reactive power target value, The plurality of inverter devices include a plurality of storage battery control devices each connected to a storage battery, the distribution ratio calculation unit calculates, for each of the plurality of storage battery control devices, a ratio of a rated capacity of each of the plurality of storage batteries to a total value of each rated capacity of the plurality of storage batteries as a distribution ratio of the storage battery control device to which the storage battery is connected; the receiving unit receives the charging rates of the storage batteries from each of the plurality of storage battery control devices; The setting unit corrects the active power target value based on a difference between an average value of each charging rate of the storage battery and each charging rate. program.

Images