Electric power system

Abstract

To provide an electric power system that can reduce the operation load on a processor.SOLUTION: An electric power system S1 is connected to an electric power system D, and supplies primary adjustment force. The electric power system S1 comprises a plurality of electric power controllers B1, and a processor A1. The processor A1 includes a generation unit 13 that generates control information by using the value of connecting point electric power and a total target. The plurality of electric power controllers B1 each includes: an adjustment width calculation unit 22 that calculates an initial adjustment width; a correction unit 29 that calculates a post-correction adjustment width from the initial adjustment width; a control value calculation unit 23 that calculates a pre-adjustment control value in consideration of the post-correction adjustment width as well as the control information; a command value calculation unit 24 that calculates an induction command value by using the pre-adjustment control value; a reference value calculation unit 25 that calculates an output reference value by using the induction command value; a target calculation unit 26 that calculates an apparatus target in consideration of the initial adjustment width as well as the output reference value; and an electric power control unit 27 that controls an electric power apparatus X so that output electric power from the electric power controller B1 becomes the apparatus target.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a power system.

Background Art

[0002] Power systems that manage a plurality of power control devices connected to a power system and control power reception from the power system are becoming widespread. For example, Patent Document 1 discloses an example of a power system including a plurality of power control devices and a processing device. The processing device calculates a guiding command value for controlling a predetermined adjustable power to a target power. Each power control device dispersedly controls the output power using the guiding command value calculated by the processing device. At this time, each power control device calculates a target value of the output power based on an optimization problem using the guiding command value. Then, the output power is controlled so that the output power becomes the target value. In this way, energy management of the power system is performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the power system described in Patent Document 1, each of a plurality of power control devices individually calculates a target value of the output power using a guiding command value. As a result, since it is not necessary for the processing device to calculate the target value of the output power of each power control device, the calculation load on the processing device is reduced. Even in such a power system, there is still room for improvement in reducing the calculation load on the processing device.

[0005] The present disclosure has been conceived in view of the above circumstances, and an object thereof is to provide a power system capable of reducing the calculation load on a processing device.

Means for Solving the Problem

[0006] The power system of the present disclosure is a power system connected to a power grid and supplying primary regulation power to the power grid. The power system includes a plurality of power control devices connected to the power grid via a connection point and performing output control of the connected power equipment, and a processing device communicable with each of the plurality of power control devices. The connection point power, which is the power at the connection point, includes the primary regulation power and the system power, which is the output power of the power system when the primary regulation power is not supplied. The processing device includes a generation unit that generates control information using the overall target, which is the target value of the system power, and the value of the connection point power, and a transmission unit that transmits the control information to each of the plurality of power control devices. Each of the plurality of power control devices includes an adjustment width calculation unit that calculates an initial adjustment width, which is a power value to be adjusted for supplying the primary regulation power, a correction unit that calculates a corrected adjustment width from the initial adjustment width, a reception unit that receives the control information, a control value calculation unit that calculates a pre-adjustment control value by taking into account the corrected adjustment width in the control information, a command value calculation unit that calculates an induction command value using the pre-adjustment control value, a reference value calculation unit that calculates an output reference value for making the system power reach the overall target using the induction command value, a target calculation unit that calculates an equipment target, which is the target value of the output power of the corresponding power control device, by taking into account the initial adjustment width in the output reference value, and a power control unit that controls the power equipment so that the output power of the corresponding power control device becomes the equipment target. The correction unit calculates the corrected adjustment width by multiplying the initial adjustment width by the ratio of the total capacity, which is the total rated capacity of the power equipment connected to each of the plurality of power control devices, to the individual capacity, which is the rated capacity of the power equipment connected to the self-device.

[0007] In a preferred embodiment of the power system, the processing device receives the information on the individual capacity from each of the plurality of power control devices, calculates the total capacity from the received information on the individual capacity, and transmits the total capacity to each of the plurality of power control devices.

[0008] In a preferred embodiment of the power system, the rated capacity of the power equipment connected to each of the plurality of power control devices is the same, and the correction unit uses the number of the power equipment as the ratio of the total capacity to the individual capacity.

[0009] In a preferred embodiment of the power system, each of the plurality of power control devices includes a filter unit that removes a variation component steeper than the frequency variation in the primary regulation force. In each of the plurality of power control devices, the adjustment width calculation unit outputs the initial adjustment width to the correction unit via the filter unit.

[0010] In a preferred embodiment of the power system, a storage battery is connected to each of the plurality of power control devices as the power equipment, and the charge and discharge of the storage battery are controlled.

Advantages of the Invention

[0011] According to the power system of the present disclosure, since each of the plurality of power control devices calculates an induction command value, the processing device only generates control information for calculating the induction command value and transmits it to the power control device. Therefore, the power system of the present disclosure can reduce the computational load of the processing device.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

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Embodiments for Carrying Out the Invention

[0013] Preferred embodiments of the power system of the present disclosure will be described below with reference to the drawings. Hereinafter, the same or similar components will be denoted by the same reference numerals, and redundant descriptions will be omitted.

[0014] FIGS. 1 and 2 show a power system S1 according to an embodiment. As shown in FIG. 1, the power system S1 includes a power line 90, a processing device A1, a plurality of power control devices B1, and power receiving equipment C1.

[0015] The power system S1 is connected to the power grid D via a connection point Y. The power system S1 can receive power from the power grid D. Also, the power system S1 can transmit power to the power grid D (can have reverse power flow). In the present disclosure, when power is output from the power system S1 to the power grid D, that is, when there is reverse power flow, it is assumed that the connection point power becomes a positive value. On the other hand, when power is output from the power grid D to the power system S1, it is assumed that the connection point power becomes a negative value. The connection point power refers to the power at the connection point Y between the power system S1 and the power grid D.

[0016] The power system S1 performs power control such that the system power, which is the output power of the power system S1, reaches the target value of the system power (hereinafter referred to as the "overall target") through the cooperation of the processing device A1 and a plurality of power control devices B1. The power control performed by the power system S1 includes, for example, output suppression control, peak cut control, reverse power flow avoidance control, and schedule control. In output suppression control, the power (sold power) output from the power system S1 to the power grid D is suppressed in accordance with an output suppression command instructed by the power company. Peak cut control suppresses the peak value of the power (purchased power) supplied from the power grid D. In reverse power flow avoidance control, the occurrence of reverse power flow is suppressed. Schedule control sets the output power of the power system S1 to the power value set by the user. The power system S1 performs any of these power controls according to the control mode set in the processing device A1.

[0017] In addition, the power system S1 supplies a primary regulation force to the power grid D by adjusting the output power to the power grid D according to the frequency fluctuation of the voltage at the connection point Y. In the power grid D, when the balance between power demand and supply (supply-demand balance) is disrupted, the voltage frequency of the power grid D fluctuates. For example, when the demand in the power grid D exceeds the supply, the frequency of the power in the power grid D decreases. In this case, the power system S1 adjusts the supply-demand balance of power by increasing the power supplied to the power grid D, thereby suppressing the decrease in the voltage frequency in the power grid D. On the other hand, when the demand in the power grid D is less than the supply, the frequency of the power in the power grid D increases. In this case, the power system S1 adjusts the supply-demand balance of power by decreasing the power supplied to the power grid D, thereby suppressing the increase in the voltage frequency in the power grid D. The primary regulation force is the power that is adjusted in response to frequency fluctuations for adjusting the supply-demand balance of power. In the present disclosure, the frequency fluctuations to which it responds are fluctuations in the "extremely short cycle" of, for example, demand fluctuations on the order of several seconds to several minutes. Therefore, the power system S1 adjusts the supply-demand balance of the power grid D by supplying a primary regulation force in response to the frequency fluctuations of the voltage at the connection point Y.

[0018] The power system S1 conducts transactions with a supply-demand adjustment market (not shown) for primary frequency regulation power as a trading target through a trading system (not shown). The supply-demand adjustment market is operated by, for example, a general power transmission and distribution company. In the supply-demand adjustment market, for example, it is divided into blocks of 3-hour units (from 0:00 to 3:00, from 3:00 to 6:00, ···, from 21:00 to 24:00), and the adjustment power (ΔkW) for each 3-hour unit is traded as a commodity block. Note that the above 3-hour unit time is just an example and can be changed according to the regulations of the supply-demand adjustment market. When a transaction with the supply-demand adjustment market is concluded, the power system S1 supplies primary frequency regulation power to the power grid D in the commodity block where the transaction is concluded. Note that the power system S1 does not supply primary frequency regulation power in time zones other than the commodity block where the transaction is concluded. The power system S1 performs power control so that the system power reaches the overall target and also performs control to supply primary frequency regulation power in the commodity block where the transaction is concluded. Therefore, in the commodity block where the transaction is concluded, the connection point power includes the system power and the primary frequency regulation power. The power system S1 performs power control so that the system power reaches the overall target in time zones other than the commodity block where the transaction is concluded and does not perform control to supply primary frequency regulation power. Therefore, in time zones other than the commodity block where the transaction is concluded, the connection point power includes the system power and does not include the primary frequency regulation power.

[0019] The power load L consumes the supplied power. The power load L is supplied with power from the power grid D and the power control device B1. The power load L includes a general load and an important load. The general load is, for example, an electrical device that is relatively less affected even if the power is cut off during a disaster, such as an air conditioner. The important load is an important load that needs to continue to be supplied with power even during a disaster, such as an emergency elevator, an electrical device that requires continuous operation, and the lighting of a building.

[0020] The power line 90 constructs the power network in the power system S1. The power system S1 is connected to the power grid D by the power line 90.

[0021] The power receiving equipment C1 is configured to include a distribution board and a sub - distribution board. The power receiving equipment C1 also includes various protection devices for connecting the power system S1 to the power grid D. The power receiving equipment C1 receives power input via the power line 90 from the power grid D, each of the plurality of power control devices B1, and the power load L. The power receiving equipment C1 supplies the received power to the power grid D, the plurality of power control devices B1, the power load L, etc. The power receiving equipment C1 is communicable with the processing device A1.

[0022] As shown in FIG. 2, the power receiving equipment C1 includes a measurement unit 31 and a communication unit 32. The measurement unit 31 is installed at the connection point Y between the power system S1 and the power grid D and detects the connection point power. The connection point power is the power with the primary regulation power superimposed on the system power. The measurement unit 31 is, for example, a power transducer. The communication unit 32 transmits the measurement result of the measurement unit 31, that is, the measured value of the connection point power, to the processing device A1.

[0023] The processing device A1 generates information (control information described later) for each of the plurality of power control devices B1 to control the output power. The processing device A1 is communicable with each of the plurality of power control devices B1 and the power receiving equipment C1 respectively. This communication may be a wireless method or a wired method. As shown in FIG. 2, the processing device A1 includes a first acquisition unit 11, a second acquisition unit 12, a generation unit 13, a reception unit 14, a transmission unit 15, and a total capacity calculation unit 16.

[0024] The first acquisition unit 11 acquires the connection point power. In this embodiment, the first acquisition unit 11 acquires the value (measured value) of the connection point power by receiving the measured value of the connection point power from the power receiving equipment C1 via the reception unit 14.

[0025] The second acquisition unit 12 acquires the overall target. For example, the second acquisition unit 12 acquires the overall target by receiving the overall target from a computer of the power company (not shown) or a computer (not shown) that inputs the settings of the processing device A1 via the reception unit 14. Alternatively, the second acquisition unit 12 may acquire the overall target by reading out the overall target stored in a storage unit (not shown) provided in the processing device A1. The second acquisition unit 12 acquires the overall target corresponding to the control mode set in the processing device A1.

[0026] The generation unit 13 generates control information using the measured value of the connection point power acquired by the first acquisition unit 11 and the overall target acquired by the second acquisition unit 12. In the present embodiment, the generation unit 13 generates the difference between the measured value of the connection point power and the overall target as the control information. That is, the control information includes a difference value ΔP that is the difference between the measured value of the connection point power and the overall target. In the present embodiment, the difference value ΔP is a value obtained by subtracting the value P of the connection point power from the overall target Pc (ΔP = Pc - P).

[0027] The total capacity calculation unit 16 acquires information on the rated capacity of the power equipment X connected from each power control device B1 via the reception unit 14. Hereinafter, the rated capacity in each power control device B1 may be referred to as "individual capacity". The total capacity calculation unit 16 adds up the acquired rated capacities (individual capacities) of the power equipment X and calculates the total value of the individual capacities. This total value may be referred to as the "total capacity".

[0028] The receiving unit 14 receives the measured value of the connection point power from the power receiving facility C1 through communication with the power receiving facility C1. Further, the receiving unit 14 receives the overall target from the aforementioned computer. Furthermore, the receiving unit 14 receives information on the rated capacity (individual capacity) of the power equipment X connected from each power control device B1. Note that the receiving unit 14 may receive the measured value of the connection point power, the overall target, and the information on the rated capacity using a common module or different modules. The transmitting unit 15 transmits control information and information on the total capacity to each power control device B1 through communication with each power control device B1. Note that the transmitting unit 15 may transmit the control information and the information on the total capacity using a common module or separate modules.

[0029] Each of the plurality of power control devices B1 is connected to the power equipment X connected to the power receiving facility C1 and controls the output of the power equipment X. In the present embodiment, as shown in FIG. 1, each power control device B1 has a storage battery BT connected as the power equipment X and controls the charge and discharge of the storage battery BT. Therefore, each power control device B1 is a storage battery power conditioner. In the following description, the power conditioner is abbreviated as "PCS". In the illustrated example, one power equipment X (storage battery BT) is connected to each power control device B1 (storage battery PCS), but a plurality of power equipment X (storage battery BT) may be connected. The storage battery BT may be a secondary battery such as a lithium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, or a lead-acid battery, or may be a capacitor such as an electric double layer capacitor. Each power control device B1 (storage battery PCS) charges the connected storage battery BT by supplying the power input from the power receiving facility C1 to the storage battery BT. Further, the power control device B1 (storage battery PCS) discharges the storage battery BT by outputting the power stored in the connected storage battery BT to the power receiving facility C1. Each power control device B1 (storage battery PCS) controls the output power of the connected storage battery BT by controlling the charge amount and discharge amount of the storage battery BT.

[0030] In the present disclosure, each power control device B1 is not limited to a battery PCS. For example, it may be a solar PCS to which a solar cell is connected as power equipment X, an EV stand to which an electric vehicle is connected as power equipment X, a generator control device to which a generator is connected as power equipment X, or a load control device to which a power load L is connected as power equipment X. The solar PCS controls the power generation amount by the solar cell. The electric vehicle in the present disclosure refers to an automobile that can run using an electric motor as a power source, and includes automobiles equipped with an internal combustion engine (for example, a plug-in hybrid vehicle). The electric motor operates by the power stored in the battery provided in the electric vehicle. The EV stand controls the charging and discharging of the electric vehicle. The generator converts, for example, the thermal energy of fuels such as oil, coal, and gas into mechanical energy, and generates electricity by this mechanical energy. The generator may be a power generation device that uses renewable energy other than sunlight (for example, wind power, hydraulic power, biomass, geothermal energy, etc.). While the solar cell directly converts solar energy into electrical energy, the generator converts energy other than electrical energy into mechanical energy and then converts the mechanical energy into electrical energy. The generator control device controls the power generation amount by the generator. The load control device controls the power load L connected to the power receiving facility C1, and is, for example, a building energy management system (BEMS) or an energy management system (FEMS) in a factory.

[0031] Each power control device B1 controls the output power based on the control information received from the processing device A1. The control of this output power includes power control for making the system power the overall target (hereinafter referred to as "system power control") and power control for supplying primary regulation power (hereinafter referred to as "primary regulation power control"). Each power control device B1 performs system power control and primary regulation power control in the commodity block where a transaction has been concluded. On the other hand, each power control device B1 performs only system power control (and does not perform primary regulation power control) during time periods other than the commodity block where a transaction has been concluded. In primary regulation power control, each power control device B1 measures the frequency of the output voltage at its own end and calculates the frequency deviation from the reference frequency. The reference frequency is the frequency defined in the power system D. For example, it is 50 Hz in eastern Japan and 60 Hz in western Japan. Also, "its own end" refers to the output end of the output power in each power control device B1. Then, according to the calculated frequency deviation, the output power is adjusted so that the frequency deviation is reduced.

[0032] As shown in FIG. 2, each of the plurality of power control devices B1 (battery PCS) includes a receiving unit 211, a transmitting unit 212, an adjustment range calculation unit 22, a control value calculation unit 23, a command value calculation unit 24, a reference value calculation unit 25, a target calculation unit 26, a power control unit 27, and a correction unit 29. Unless otherwise specified, these components described below are common to each power control device B1.

[0033] The receiving unit 211 receives control information (difference value ΔP) from the processing device A1 through communication with the processing device A1. The control information received by the receiving unit 211 is output to the control value calculation unit 23. Also, the receiving unit 211 receives information on the total capacity from the processing device A1 through communication with the processing device A1. The information on the total capacity received by the receiving unit 211 is output to the correction unit 29. The receiving unit 211 may receive the control information and the information on the total capacity using a common module or using different modules.

[0034] The transmission unit 212 transmits information on the rated capacity (individual capacity) of the power equipment X (battery BT) to the processing device A1 through communication with the processing device A1. The information on the individual capacity transmitted by the transmission unit 212 may be stored in the connected power equipment X (battery BT) and acquired from the power equipment X (battery BT), or may be stored in the corresponding power control device B1.

[0035] The adjustment range calculation unit 22 calculates an adjustment range, which is a power value to be adjusted for supplying the primary adjustment force. Since each power control device B1 reduces the frequency deviation by supplying the primary adjustment force, the adjustment range is the magnitude of the power to be adjusted for reducing the frequency deviation at the output end of the power control unit 27. The adjustment range (absolute value) can also be said to be the control target of the primary adjustment force in the primary adjustment force control. The adjustment range calculation unit 22 calculates an adjustment range corresponding to the frequency deviation at the output end of the power control unit 27. The adjustment range calculation unit 22 calculates the adjustment range in the primary adjustment force control. Therefore, in time zones other than the time zone of the commodity block for which the transaction has been established, the adjustment range is not calculated (or the adjustment range is set to 0). The adjustment range calculation unit 22 outputs the calculated adjustment range to the control value calculation unit 23. Hereinafter, the adjustment range calculated by the adjustment range calculation unit 22 is referred to as the "initial adjustment range".

[0036] For example, the adjustment range calculation unit 22 calculates the initial adjustment range as follows. First, the adjustment range calculation unit 22 measures the frequency of the output voltage of the power control unit 27 as the output frequency using a measuring instrument (not shown). Next, the adjustment range calculation unit 22 calculates the frequency deviation (output frequency - reference frequency) of the output frequency from the above-mentioned reference frequency. The reference frequency is stored in the adjustment range calculation unit 22 in advance. Next, the adjustment range calculation unit 22 calculates the initial adjustment range according to the frequency deviation.

[0037] When the demand in the power system D exceeds the supply, the frequency of the power in the power system D decreases. Therefore, since the measured value of the output frequency becomes smaller than the reference frequency, the calculated frequency deviation (output frequency - reference frequency) becomes a negative value. When the calculated frequency deviation is a negative value, the adjustment width calculation unit 22 calculates, for example, a positive initial adjustment width in order to increase the output power of the power control unit 27. On the other hand, when the demand in the power system D is less than the supply, the frequency of the power in the power system D increases. Therefore, since the measured value of the output frequency becomes larger than the reference frequency, the calculated frequency deviation (output frequency - reference frequency) becomes a positive value. When the calculated frequency deviation is a positive value, the adjustment width calculation unit 22 calculates, for example, a negative initial adjustment width in order to decrease the output power of the power control unit 27. Also, when the demand and the supply in the power system D are in agreement, the measured value of the output frequency becomes the same as the reference frequency, so the calculated frequency deviation (output frequency - reference frequency) becomes 0 (zero). When the calculated frequency deviation is 0 (zero), the adjustment width calculation unit 22 sets the initial adjustment width to 0 (zero), for example, in order to maintain the current output power of the power control unit 27.

[0038] Note that the adjustment width calculation unit 22 may calculate the initial adjustment width in consideration of a predetermined setting item in addition to the frequency deviation. The predetermined setting item includes, for example, the regulation rate, the reference frequency, the rated output of the power control unit 27, and the reference frequency. These setting items may be stored in the adjustment width calculation unit 22 in advance, or may be acquired from other components as necessary. The adjustment width calculation unit 22 calculates the initial adjustment width, for example, by performing the operation of the following formula (1). In the following formula (1), P ctl_t1 is the initial adjustment width, dF is the frequency deviation (preferably the frequency deviation with upper limit constraint), Pc is the rated output of the power control unit 27, F ref is the reference frequency, and R is the regulation rate. By considering the above-described setting items in this way, the initial adjustment width can be calculated with higher accuracy. Note that the setting item is not limited to the above example. Also, the operation performed by the adjustment width calculation unit 22 is not limited to the following formula (1).

Equation

[0039] The correction unit 29 corrects the initial adjustment width and outputs it as the adjusted width after correction. The correction unit 29 calculates the adjusted width after correction by multiplying the initial adjustment width by a correction coefficient. Therefore, the correction unit 29 multiplies the initial adjustment width by P ctl_t1 , and the adjusted width after correction by P ctl_t2 , with the correction coefficient being K, and performs the operation of the following formula (2). The correction coefficient K is the ratio of the total capacity to the individual capacity. The individual capacity is the rated capacity (individual capacity) of the electrical equipment X (battery BT) connected to the power control device B1 provided with the correction unit 29, and the total capacity is the sum of the rated capacities of the electrical equipment X (battery BT) respectively connected to a plurality of power control devices B1. Therefore, if the individual capacity in the i-th power control device B1 is W i , it is given by the following formula (3) (where i is a positive integer and n is the number of power control devices B1). That is, the correction unit 29 calculates the adjusted width after correction by multiplying the initial adjustment width by the ratio of the total capacity to the individual capacity. For example, in a configuration where the power system S1 includes two power control devices B1, from the following formula (3), the correction coefficient K is as shown in the following formula (4). Therefore, the correction unit 29 of the first power control device B1 calculates the adjusted width after correction P ctl_t2 by performing the operation of the following formula (5). The correction unit 29 outputs the calculated adjusted width after correction to the control value calculation unit 23.

Equation

[0040] The control value calculation unit 23 calculates the pre-adjustment control value by taking into account the adjusted width after correction in the control information. In this embodiment, the reception unit 211 receives the difference value ΔP as the control information, and the control value calculation unit 23 calculates the pre-adjustment control value by subtracting the adjusted width after correction from the difference value ΔP. That is, the pre-adjustment control value = difference value ΔP - adjusted width after correction.

[0041] The command value calculation unit 24 calculates an induction command value using the pre-adjustment control value. The induction command value is a value for the power control device B1 to calculate the output reference value described later. For example, the command value calculation unit 24 calculates the induction command value pr(t) by solving the state equations (simultaneous differential equations) shown in the following equations (6) and (7). In the following equations (6) and (7), Px is the pre-adjustment control value (ΔP - corrected adjustment width), λ(t) is the state variable, pr(t) is the induction command value, and ε is the gradient coefficient. This state equation is set in the power control device B1. The command value calculation unit 24 calculates the induction command value every predetermined time (for example, 1 [sec]). The induction command value calculated by the command value calculation unit 24 is output to the reference value calculation unit 25.

Number

[0042] The reference value calculation unit 25 calculates the reference value (output reference value) of the output power of the corresponding power device X based on an optimization problem using the induction command value. The output reference value is the value of the output power assumed when individual output adjustment (adjustment in primary adjustment force) corresponding to the frequency deviation is not performed, and corresponds to the value of the output power for controlling the system power to the overall target. This optimization problem includes an evaluation function and constraint conditions. The evaluation function is, for example, the same as that described in Patent Document 1. In the present embodiment, the reference value calculation unit 25 performs the operations of the following equations (8) and (9) derived from the evaluation function in the same manner as described in Patent Document 1. In the following equations (8) and (9), P ref is the output reference value of the power control device B1, pr is the induction command value, pr lmt is the induction command value limit, and a1 to a4 are design parameters respectively. The induction command value limit pr lmtThe design parameters a1 to a4 are the same as those described in Patent Document 1. And, in the same manner as described in Patent Document 1, the output reference value is calculated by correcting the calculation result according to the constraint conditions. The constraint conditions are the same as those described in Patent Document 1. Differently, the reference value calculation unit 25 may calculate the output reference value by solving the evaluation function under the constraint conditions. The output reference value calculated by the reference value calculation unit 25 is output to the target calculation unit 26.

Number

[0043] The target calculation unit 26 calculates the device target in consideration of the initial adjustment width for the output reference value. The device target is the target value of the output power of the corresponding power device X. In the present embodiment, the target calculation unit 26 calculates the device target by adding the initial adjustment width to the output reference value. That is, the device target = output reference value + initial adjustment width. The device target calculated by the target calculation unit 26 is output to the power control unit 27.

[0044] The power control unit 27 controls the device power of the corresponding power device X so that the output power of the corresponding power device X (hereinafter referred to as "device power") becomes the device target. Therefore, in the example where the power control device B1 is a battery PCS, the power control unit 27 controls the charging power and the discharging power of the battery BT as the power device X based on the device target. For example, when the device target is a positive value, the power control unit 27 discharges the battery BT, and when the device target is a negative value, the power control unit 27 charges the battery BT. In the example where the power control device B1 is a solar power PCS, the power control unit 27 controls the generated power of the solar cell as the power device X based on the device target. Also, in the example where the power control device B1 is an EV stand, the power control unit 27 controls the charging power and the discharging power of the electric vehicle as the power device X based on the device target. Further, in the example where the power control device B1 is a generator control device, the power control unit 27 controls the generated power of the generator as the power device X based on the device target. Also, in the example where the power control device B1 is a load control device, the power control unit 27 controls the power consumption of the power load L as the power device X based on the device target.

[0045] In the power system S1 configured as described above, the processing device A1 acquires the value of the connection point power and the overall target, and generates control information (the difference value ΔP in this embodiment). Then, the processing device A1 transmits the control information to each power control device B1. Each power control device B1 calculates a pre-adjustment control value by taking into account the corrected adjustment width in the control information received from the processing device A1. In this embodiment, the power control device B1 calculates the pre-adjustment control value by subtracting the corrected adjustment width from the difference value ΔP. Then, using the calculated pre-adjustment control value, an induction command value is calculated by a preset state equation (the above equations (6) and (7)). Each power control device B1 calculates an output reference value of the power equipment X to be controlled based on a preset optimization problem using the calculated induction command value, and calculates a device target by taking into account the initial adjustment width in the output reference value. In this embodiment, each power control device B1 calculates the device target by adding the initial adjustment width to the output reference value. Then, the output power of the power equipment X to be controlled is controlled so that it becomes the device target. Thus, the power system S1 controls the output power so as to reduce the frequency deviation while setting the system power as the overall target. That is, the power system S1 performs power control to set the system power as the overall target, and supplies a primary adjustment force in response to frequency fluctuations.

[0046] Figure 3 is a schematic diagram for verifying the operation of power control in the power system S1 of this embodiment. Fig. 3(a) is a block diagram showing the power system S1 equipped with two power control devices B1, and Fig. 3(b) is a block diagram showing a power system (hereinafter referred to as "comparative power system") in the case where each of the two power control devices B1 does not include a correction unit 29. In each verification in Figs. 3(a) and (b), the power consumption of the power load L is 200 kW and the overall target is 50 kW. Also, it is assumed that the rated capacities (individual capacities) of the power equipment X (battery BT) connected to the two power control devices B1 are the same. Therefore, the correction coefficient K in each power control device B1 is 2 from the above formula (3). Also, in each of Figs. 3(a) and (b), it is assumed that it is necessary to supply a primary adjustment force of 50 kW to the power system D due to the frequency fluctuation generated in the power system D. In each verification in Figs. 3(a) and (b), assuming that the connection point power P input to the processing device A1 is 100 kW, it was confirmed whether the output power in the power receiving facility C1 becomes 100 kW.

[0047] In the power system S1 shown in Fig. 3(a), as described above, the connection point power P input to the processing device A1 is 100 kW and the overall target is 50 kW, so the control information (difference value ΔP) output from the processing device A1 is -50 kW. Therefore, each power control device B1 receives control information with a difference value ΔP of -50 kW from the processing device A1.

[0048] In the power system S1, since a plurality of power control devices B1 are connected in parallel to the power system D, the frequency fluctuations (frequency drops) generated in the output voltages of the power control devices B1 are the same. Therefore, in the example shown in Fig. 3(a), the adjustment width calculation units 22 of the power control devices B1 each calculate 50 kW as the initial adjustment width P ctl_t1 as.

[0049] Next, the correction unit 29 calculates the corrected adjustment width P ctl_t1 from the initial adjustment width P ctl_t2 In Fig. 3(a), as described above, the correction coefficient K is 2, so the corrected adjustment width P ctl_t2It becomes 100 kW and is input to the control value calculation unit 23. In the control value calculation unit 23, from the control information (differential value ΔP = -50 kW), the adjusted adjustment width P ctl_t2 (= 100 kW) is subtracted, and the pre-adjustment control value is calculated. Since the differential value ΔP is -50 kW and the adjusted adjustment width P ctl_t2 is 100 kW, the pre-adjustment control value is -150 kW. Using this pre-adjustment control value (-150 kW), the command value calculation unit 24 calculates the induction command value pr, and the reference value calculation unit 25 calculates the output reference value P ref from the induction command value pr. For the convenience of understanding, considering the calculation of the output reference value P ref from the pre-adjustment control value simply, the output reference value P ref is calculated as follows. In the command value calculation unit 24, for the entire power system S1, the induction command value pr for changing the pre-adjustment control value of -150 kW to the overall target of 50 kW (that is, the induction command value pr for the total output of the two power control devices B1 to be 200 kW) is calculated. In the reference value calculation unit 25, using this induction command value pr, the output power of the corresponding power control device B1 is calculated. So, for example, if it is equally divided between the two power control devices B1, the output reference value P ref is 100 kW. In actuality, in the reference value calculation unit 25, the situation (state of charge of the storage battery BT) and specifications (rated output, etc.) of the corresponding power control device B1 are considered, and the output reference value P ref of its own device is calculated.

[0050] After that, the target calculation unit 26 adds the initial adjustment width P ref to the output reference value P ctl_t1 to calculate the equipment target. Since the output reference value P ref is 100 kW and the initial adjustment width P ctl_t1Since it is 50 kW, the equipment target becomes 150 kW. Then, the power control unit 27 performs power control so that the output power Pout becomes 150 kW. As a result, since the output power Pout of 150 kW is output from each power control device B1, the total of the output power Pout of the two power control devices B1 becomes 300 kW, and since 200 kW is consumed by the power load L, the connection point power P becomes 100 kW. Therefore, in the power system S1, it can be seen that while setting the system power to the overall target of 50 kW, the power system as a whole can supply a primary regulation power of 50 kW.

[0051] On the other hand, when the correction unit 29 is not provided, as shown in Fig. 3(b), the control value calculation unit 23 outputs the initial adjustment width P ctl_t1 of 50 kW. Therefore, in the control value calculation unit 23, the initial adjustment width P ctl_t1 (=50 kW) is subtracted from the control information (difference value ΔP = -50 kW), and the pre-adjustment control value is calculated. Since the difference value ΔP is -50 kW and the initial adjustment width P ctl_t1 is 50 kW, the pre-adjustment control value becomes -100 kW. Using this pre-adjustment control value (-100 kW), the command value calculation unit 24 calculates the induction command value pr, and the reference value calculation unit 25 calculates the output reference value P ref from the induction command value pr. For the sake of easy understanding, similar to the verification in the above-described power system S1, when simply considering the calculation of the output reference value P ref from the pre-adjustment control value, the output reference value P ref of each power control device B1 becomes 75 kW so that the pre-adjustment control value (=-100 kW) becomes the overall target (=50 kW) in the entire power system to be compared.

[0052] After that, the target calculation unit 26 adds the initial adjustment width P ref to the output reference value P ctl_t1 to calculate the equipment target. Since the output reference value P ref is 75 kW and the initial adjustment width P ctl_t1Since it is 50 kW, the equipment target is 125 kW. Then, the power control unit 27 performs power control so that the output power Pout becomes 125 kW. As a result, since the output power Pout of 125 kW is output from each of the power control devices B1, the total of the output power Pout of the two power control devices B1 becomes 250 kW, and since 200 kW is consumed by the power load L, the connection point power P becomes 50 kW. Therefore, in the power system for comparison that does not include the correction unit 29 shown in FIG. 3(b), since the output power from the power receiving facility C1 and the connection point power input to the processing device A1 do not match, it can be seen that the power control to the overall target of the system power and the supply of the primary regulation power cannot be performed simultaneously.

[0053] From the above verification results, the following can be understood. In the power system of the present disclosure, a plurality of power control devices B1 are provided, and each of the plurality of power control devices B1 detects frequency fluctuations in the output voltage and supplies a primary regulation force. For this reason, from the power receiving facility C1, power that is several times the number of the plurality of power control devices B1 is output with respect to the primary regulation force to be supplied as the power system S1. In such a configuration, in the case where there is no correction unit 29 as in the power system to be compared, the control value calculation unit 23 uses only the primary regulation force for one unit as the adjustment range (initial adjustment range) and takes it into account in the control information (the difference between the connection point power and the overall target). Therefore, in each power control device B1, the magnitude (adjustment range) of the primary regulation force to be adjusted is insufficient, and among the difference between the connection point power and the overall target, the difference in the case where the primary regulation force is not supplied cannot be correctly detected. For this reason, as shown in FIG. 3(b), the power output from the power receiving facility C1 differs from an appropriate value (100 kW in the example of FIG. 3(b)). On the other hand, in the power system S1, each power control device B1 is provided with a correction unit 29, and the adjustment range (initial adjustment range) calculated by the adjustment range calculation unit 22 is corrected to the corrected adjustment range. As a result, the control value calculation unit 23 can take into account the primary regulation force for a plurality of units as the adjustment range (corrected adjustment range) in the control information (the difference between the connection point power and the overall target), so that among the difference between the connection point power and the overall target, the difference in the case where the primary regulation force is not supplied can be correctly detected. Therefore, in the power system S1, as shown in FIG. 3(a), the power output from the power receiving facility C1 becomes an appropriate value (100 kW in the example of FIG. 3(a)). From the above, even in the case where the power system S1 includes a plurality of power control devices B1 and the primary regulation force is supplied by the plurality of power control devices B1, power control can be performed so that the system power becomes the overall target.

[0054] FIG. 4 shows the simulation results of power control in the power system S1. In the simulation, the frequency of the power in the power grid D was changed, and the ideal power target value and the actual power target value (control result) in the power system S1 at that time were confirmed. FIG. 4(a) shows the actual power target value P real(Control result) and the ideal power target value P id show the respective time changes with. In Fig. 4(a), the actual power target value P real (control result) is shown by a solid line, and the ideal power target value P id is shown by a dashed-dotted line. Fig. 4(b) shows the time change of the frequency deviation dF calculated by the adjustment width calculation unit 22, which corresponds to the time change of the frequency of the power in the power system D. Fig. 4(c) shows the time change of the overall target Pc. In the simulation, as shown in Fig. 4(c), the overall target Pc was set to 1000 kW at the start and then changed to 800 kW at time t1. In the simulation, communication delays between the processing device A1 and each power control device B1, processing delays inside each power control device B1 (including communication delays between components of each power control device B1), and communication delays between the power receiving facility C1 and the processing device A1, etc., are not considered (it is assumed that there are no such control delays as described above).

[0055] From the start to time t1, there is no frequency change in the power system D, and for the overall target Pc (1000 kW), the actual power target value P real and the ideal power target value P id coincide at 1000 kW. Then, when the overall target Pc is changed to 800 kW at time t1, the actual power target value P real also converges to 800 kW.

[0056] After that, when the frequency deviation dF (the frequency of the power in the power system D) is changed after time t2, the ideal power target value P id changes with the change of this frequency deviation dF. For example, in this embodiment, as described above, when the frequency of the power in the power system D decreases and the calculated frequency deviation (output frequency - reference frequency) becomes a negative value, the output power of the power control unit 27 is increased. Therefore, as shown in Fig. 4, when the frequency deviation dF is a negative value, the ideal power target value P idbecomes larger than the overall target Pc. Conversely, when the frequency of the power in the power system D increases and the calculated frequency deviation (output frequency - reference frequency) becomes a positive value, the output power of the power control unit 27 is decreased. Therefore, as shown in FIG. 4, when the frequency deviation dF is a positive value, the ideal power target value P id becomes smaller than the overall target Pc. Also, according to the magnitude of the frequency deviation dF, the difference between the ideal power target value P id with respect to the overall target becomes larger. In this way, due to the change in the frequency deviation dF, the ideal power target value P id changes. With respect to this ideal power target value P id , the actual power target value P real (control result) of the power system S1 is in agreement as shown in FIG. 4(a). That is, it can be seen from this simulation result that the power system S1 can realize the expected operation (simultaneous execution of system power control and primary regulation power control) in response to the change in the frequency deviation dF (frequency fluctuation of the power in the power system D).

[0057] The actions and effects of the power system S1 of the present disclosure are as follows.

[0058] In the power system S1, the processing device A1 generates control information and transmits the generated control information to each of the plurality of power control devices B1. Each of the plurality of power control devices B1 receives the control information and calculates an induction command value using the received control information. Then, using the calculated induction command value, a device target is calculated and the output power is controlled. In this configuration, each of the plurality of power control devices B1 calculates an induction command value. Therefore, the processing device A1 only generates the control information for calculating the induction command value and transmits it to each power control device B1. Therefore, the power system S1 can reduce the computational load of the processing device A1 compared to the power system described in Patent Document 1.

[0059] In particular, in the power system S1, each power control device B1 detects the frequency fluctuation of the output voltage at its own end by the adjustment range calculation unit 22, and calculates an adjustment range (initial adjustment range) according to the frequency fluctuation. Then, the correction unit 29 corrects the initial adjustment range to a corrected adjustment range by a correction coefficient K corresponding to the rated capacity of each of the plurality of power control devices B1. Thereafter, the control value calculation unit 23 calculates a pre-adjustment control value that takes into account the corrected adjustment range in the control information, and the command value calculation unit 24 calculates an induction command value using the pre-adjustment control value. When the induction command value is calculated, the reference value calculation unit 25 calculates an output reference value, and the target calculation unit 26 calculates an equipment target by taking into account the initial control width in the output reference value. According to this configuration, even when each of the plurality of power control devices B1 individually supplies a primary adjustment force according to the frequency fluctuation of the output voltage at its own end, the control value calculation unit 23 can calculate the pre-adjustment control value when no primary adjustment force is supplied. Therefore, as understood from the verification results in Fig. 3(a), even when each of the plurality of power control devices B1 in the power system S1 supplies a primary adjustment force according to the frequency fluctuation of the output power at its own end, the system power control and the primary adjustment force control can be controlled respectively, so that the supply of the primary adjustment force can be properly performed.

[0060] In the above embodiment, the generation unit 13 generates the difference (difference value ΔP) between the value of the connection point power and the overall target as control information. Different from this configuration, the generation unit 13 may generate the value of the connection point power and the overall target as control information. That is, the control information may include the value of the connection point power and the overall target instead of the difference value ΔP. In this case, the control value calculation unit 23 may calculate the difference (difference value ΔP) between the value of the connection point power and the overall target from the received control information, and calculate the pre-adjustment control value by subtracting the corrected adjustment range from the calculated difference value ΔP. According to this configuration, the processing device A1 only needs to transmit the obtained value of the connection point power and the overall target as it is as control information to the power control device B1. Therefore, the power system according to this modification example can further reduce the calculation load of the processing device A1 compared with the above power system S1.

[0061] In the above-described embodiment, an example was shown in which the processing device A1 acquires information on the individual capacities of the electrical equipment X connected from each power control device B1, sums up the rated capacities of the acquired electrical equipment X, and calculates the total capacity (the total value of the rated capacities). Different from this configuration, any one of the plurality of power control devices B1 may serve as a master device, acquire information on individual capacities from other power control devices B1, and calculate the total capacity. In this example, information on the total capacity is transmitted from the power control device B1 serving as the master device to other power control devices B1. Alternatively, each of the plurality of power control devices B1 may acquire information on individual capacities from other power control devices B1 and calculate the total capacity. Alternatively, information on the total capacity may be stored in advance in the processing device A1 or each power control device B1. However, in the configuration where the processing device A1 or the power control device B1 calculates the information on the total capacity, it is more preferable than the configuration in which the information on the total capacity is stored in advance in the processing device A1 or the power control device B1 in the following point. That is, since the processing device A1 or each power control device B1 calculates the total capacity by calculation, even if the number of power control devices B1 connected to the power system D changes, the information on the total capacity is automatically updated according to the change in the number.

[0062] In the above-described embodiment, when the individual capacities of the respective power control devices B1 are all the same, the correction unit 29 may use, as the correction coefficient K, not the value obtained from the calculation of the above equation (4), but the number of the plurality of power control devices B1 (hereinafter sometimes referred to as "the number of devices"). That is, the correction unit 29 may calculate, as the corrected adjustment width, a value obtained by multiplying the initial adjustment width by the number of the plurality of power control devices B1 (the number of devices). In the case where the individual capacities of the respective power control devices B1 are all the same, it can be understood from the calculation of the above equation (4) that the correction coefficient K of each power control device B1 becomes the number of devices. In this modification, the processing device A1 may simply total the number of the plurality of power control devices B1 (the number of devices) connected to the connection point Y and transmit the total to each power control device B1. According to this modification, since the processing device A1 only needs to total the number of devices, it becomes easy to calculate the correction coefficient K. Note that, unlike the configuration in which the processing device A1 totals the number of devices, each power control device B1 may total the number of devices by individual communication with other power control devices B1. Alternatively, the number of devices may be stored in advance in the processing device A1 or each power control device B1. However, the configuration in which the processing device A1 or each power control device B1 totals the number of devices is more preferable than the configuration in which the number of devices is stored in advance in the processing device A1 or each power control device B1 in the following respect. That is, since the processing device A1 or each power control device B1 can automatically detect the number of devices, even if the number of devices changes, the correction coefficient K is automatically updated according to the change in the number of devices.

[0063] FIG. 5 shows a power system S2 according to the first modification of the present disclosure. Note that FIG. 5 shows only one of the plurality of power control devices B1, and the overall configuration is the same as that of the power system S1 (see FIG. 2). The power system S2 is different from the power system S1 in the following points. That is, each of the plurality of power control devices B1 includes a filter unit 281. The filter unit 281 is, for example, a low-pass filter, and removes a variation component that is steeper than the frequency variation in the primary regulation power (variation in the very short-term period described above). Further, the filter unit 281 suppresses a decrease in control accuracy with respect to each control delay such as a communication delay between the processing device A1 and each power control device B1, a processing delay inside each power control device B1 (including a communication delay between components of each power control device B1), and a communication delay between the power receiving facility C1 and the processing device A1.

[0064] The filter unit 281 is connected between the adjustment width calculation unit 22 and the correction unit 29. Therefore, the output signal (initial adjustment width) of the adjustment width calculation unit 22 is input to the correction unit 29 via the filter unit 281. In the power system D, when high-speed disturbance noise is superimposed, a variation steeper than the variation in the very short period may occur in the value of the output frequency measured by the adjustment width calculation unit 22. Then, due to such a steep variation in the output frequency, a steep variation may also occur in the output signal of the adjustment width calculation unit 22. Therefore, the filter unit 281 removes the steep variation included in the output signal of the adjustment width calculation unit 22.

[0065] FIG. 6 shows the simulation results of power control in the power system S2. FIG. 6(a) shows the results when the filter unit 281 is not provided, and FIG. 6(b) shows the results when the filter unit 281 is provided. In each of FIGS. 6(a) and 6(b), the solid line shows the time change of the actual power target value P real (control result), and the dashed-dotted line shows the time change of the ideal power target value P id . In the simulation, the change in the frequency of the power in the power system D (the time change of the frequency deviation dF calculated by the adjustment width calculation unit 22) and the change in the overall target Pc are the same as those in FIGS. 4(b) and 4(c), respectively.

[0066] As shown in Fig. 6(a), when the filter unit 281 is not provided, at times t2, t5, t6, t9, t10, t13, t14 (see Fig. 4(b)) when the frequency deviation dF decreases (i.e., at the timing when each power control device B1 increases the output power), the actual power target value P real (control result) overshoots the ideal power target value P id and at times t3, t4, t7, t8, t11, t12, t15, t16 (see Fig. 4(b)) when the frequency deviation dF increases (i.e., at the timing when each power control device B1 decreases the output power), the actual power target value P real (control result) undershoots the ideal power target value P id . This is because due to the above control delay, the synchronization of each control information is poor, and after each power control device B1 reacts on its own to the frequency deviation, the control is carried out in the reverse direction with a delay, resulting in a deterioration of the operation accuracy. On the other hand, as shown in Fig. 6(b), when the filter unit 281 is provided, no overshoot or undershoot is observed at the timing when the frequency deviation dF changes, and the actual power target value P real (control result) coincides with the ideal power target value P id . This is because the filter unit 281 suppresses the behavior due to the above-mentioned poor synchronization and improves the deterioration of the operation accuracy. Thus, from this simulation result, it can be seen that the power system S2 can suppress the decrease in control accuracy for each control delay by providing the filter unit 281.

[0067] Also in the power system S2, similar to the power system S1, the calculation load of the processing device A1 can be reduced compared to the power system described in Patent Document 1. Further, also in the power system S2, similar to the power system S1, even when each of the plurality of power control devices B1 supplies a primary regulation force in response to the frequency fluctuation of the output voltage at its own end, the system power control and the primary regulation force control can be controlled individually, so that the supply of the primary regulation force can be appropriately performed.

[0068] In the power system S2, each of the plurality of power control devices B1 includes a filter unit 281. As a result, even during a time when frequency fluctuations in the power grid D are unstable, the influence due to the superimposition of high-speed disturbance noise (noise steeper than an extremely short period) is suppressed, enabling stable control. That is, the power system S2 can more stably control system power control and primary regulation power control. Further, the power system S2 can suppress a decrease in control accuracy with respect to each of the aforementioned control delays by the filter unit 281.

[0069] In the above-described first modification example (power system S2), an example in which each of the plurality of power control devices B1 includes the filter unit 281 was shown. However, in addition to or instead of the filter unit 281, a filter unit 282 connected between the receiving unit 211 and the control value calculation unit 23 may be provided. For example, FIG. 7 shows a configuration example of the power control device B1 including the two filter units 281 and 282. The filter unit 282 is, for example, a low-pass filter, similar to the filter unit 281. In the configuration including the filter unit 282, the output signal (control information) of the receiving unit 211 is input to the control value calculation unit 23 via the filter unit 282. In the power grid D, when high-speed disturbance noise is superimposed, the value of the connection point power measured by the measurement unit 31 may have a more abrupt change than the fluctuation in an extremely short period. Then, due to such an abrupt change in the connection point power, the output signal (control information transmitted from the processing device A1) of the receiving unit 211 may also change abruptly. Therefore, the filter unit 282 removes the abrupt change included in the output signal (control information) of the receiving unit 211. Note that an initial adjustment range is input to the filter unit 281, and control information is input to the filter unit 282. The initial adjustment range is mainly related to the control amount of the output power by the primary adjustment force, and the control information is mainly related to the control amount of the system power. Also, the primary adjustment force control is required to respond faster than the system power control. Therefore, if an abrupt change occurs in the initial adjustment range, there is a risk of destabilizing the equipment target more than when an abrupt change occurs in the control information. For these reasons, when the power control device B1 includes either one of the two filter units 281 and 282, the filter unit 281 is more preferable than the filter unit 282 in stabilizing the equipment target, that is, in stabilizing the output power of the power system S2.

[0070] FIG. 8 shows a power system S3 according to the second modification example of the present disclosure. The power system S3 is different from the power system S1 in the following points. That is, the processing device A1 of the power system S1 uses the measured value (the measured value by the measurement unit 31) as the value of the connection point power, whereas the processing device A1 of the power system S3 uses the estimated value as the value of the connection point power.

[0071] In the power system S3, the transmission unit 212 of each power control device B1 receives, from the power control unit 27, the value of the output power (control power) of the power equipment X connected to the power control unit 27. Since the power control unit 27 detects the value of the output power in controlling the output power, it may output that value to the transmission unit 212. The transmission unit 212 transmits the input value of the output power to the processing device A1. That is, the value of the output power of the power equipment X is transmitted to the processing device A1.

[0072] Also, the power system S3 includes a load monitoring unit 40. The load monitoring unit 40 monitors the power consumption of the power load L. The load monitoring unit 40 transmits the value of the power consumption of the power load L to the processing device A1.

[0073] In the power system S3 configured as described above, the processing device A1 receives the value of the output power from each of the plurality of power control devices B1, and also receives the value of the power consumption of the power load L from the load monitoring unit 40. Then, the processing device A1 calculates, as an estimated value of the connection point power, the value of the connection point power (for example, the sum of these) calculated from the received value of the output power and the value of the power consumption of the power load L. Thereby, the processing device A1 may create control information from the estimated value of the connection point power. Note that in the power system S3, since the estimated value is used as the value of the connection point power, the power receiving facility C1 may not include the measurement unit 31 and the communication unit 32 as shown in FIG. 8.

[0074] Also in the power system S3, similar to the power system S1, the arithmetic load on the processing device A1 can be reduced more than in the power system described in Patent Document 1. Further, also in the power system S3, similar to the power system S1, even when each of the plurality of power control devices B1 supplies a primary regulation force in response to a frequency fluctuation of the output voltage at its own end, the system power control and the primary regulation force control can be controlled individually, so that the supply of the primary regulation force can be appropriately performed.

[0075] In the above-described second modification example (power system S3), the processing device A1 has shown an example in which the estimated value is used as the value of the connection point power. However, different from this example, by providing the power receiving facility C1 with the measurement unit 31 and the communication unit 32, the measured value and the estimated value thereof may be selectively used as the value of the connection point power. In this configuration, the processing device A1 can switch whether to use the measured value of the connection point power or the estimated value of the connection point power, for example, according to the set control mode.

[0076] The power system according to the present disclosure is not limited to the above-described embodiments. The specific configuration of each part of the power system of the present disclosure can be freely designed in various ways.

Explanation of Reference Numerals

[0077] S1, S2, S3: Power systems, A1: Processing device, 11: First acquisition unit, 12: Second acquisition unit, 13: Generation unit, 15: Transmission unit, B1: Power control device, 211: Reception unit, 22: Adjustment width calculation unit, 23: Control value calculation unit, 24: Command value calculation unit, 25: Reference value calculation unit, 26: Target calculation unit, 27: Power control unit, 281: Filter unit, X: Power equipment, BT: Battery, L: Power load (load), D: Power system, Y: Connection point

Claims

1. A power system connected to a power grid and supplying primary regulation power to the power grid, comprising: a plurality of power control devices connected to the power grid via connection points and performing output control of the connected power equipment; a processing device capable of communicating with each of the plurality of power control devices; The connection point power, which is the power at the connection point, includes the primary regulation power and the system power, which is the output power of the power system when the primary regulation power is not supplied. The processing device includes: a generation unit that generates control information using an overall target that is a target value of the system power and a value of the connection point power; a transmission unit that transmits the control information to each of the plurality of power control devices. Each of the plurality of power control devices includes: an adjustment width calculation unit that calculates an initial adjustment width, which is a power value to be adjusted for supplying the primary regulation power; a correction unit that calculates a corrected adjustment width from the initial adjustment width; a reception unit that receives the control information; a control value calculation unit that calculates a pre-adjustment control value by taking into account the corrected adjustment width in the control information; a command value calculation unit that calculates an induction command value using the pre-adjustment control value; a reference value calculation unit that calculates an output reference value for making the system power reach the overall target using the induction command value; a target calculation unit that calculates a device target, which is a target value of the output power of the corresponding power control device, by taking into account the initial adjustment width in the output reference value; a power control unit that controls the power equipment so that the output power of the corresponding power control device reaches the device target. The correction unit calculates the corrected adjustment width by multiplying the initial adjustment width by a ratio of a total capacity, which is a sum of rated capacities of the power equipment connected to each of the plurality of power control devices, to an individual capacity, which is the rated capacity of the power equipment connected to the own device. A power system.

2. The processing device receives the individual capacity information from each of the plurality of power control devices, calculates the total capacity from the received individual capacity information, and transmits the calculated total capacity to each of the plurality of power control devices. The power system according to claim 1.

3. The rated capacities of the power equipment connected to each of the plurality of power control devices are the same. The correction unit uses the number of the power equipment as a ratio of the total capacity to the individual capacity. The power system according to claim 1.

4. Each of the plurality of power control devices includes a filter unit that removes a variation component steeper than the frequency variation in the primary regulation force. In each of the plurality of power control devices, the adjustment width calculation unit outputs the initial adjustment width to the correction unit via the filter unit. The power system according to claim 1.

5. Each of the plurality of power control devices has a storage battery connected thereto as the power equipment, and controls charging and discharging of the storage battery. The power system according to any one of claims 1 to 4.

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