Power system

Abstract

To provide a power system which can improve a response characteristic until a value of a connection point power becomes a system target value even if the number of power control devices is small.SOLUTION: A power system S1 includes a processing device A1 and a plurality of power control devices B1. The processing device A1 includes a command value calculation unit 13 which calculates an induction command value for making a value of connection point power to a system target value. Each of the plurality of power control devices B1 includes: a target calculation unit 22 for calculating an apparatus target of a connected power apparatus using the induction command value; and a power control unit 23 which controls the power apparatus so that output of the connected power apparatus becomes the apparatus target. The command value calculation unit 13 includes: a first compensator 131 for outputting a first command value with the value of connection point power and the system target value as input; a second compensator 132 for outputting a second command value with the system target value as input; and an adder 133 for adding the first command value and the second command value and outputting the common induction command value in the plurality of power control devices.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to power systems. [Background technology]

[0002] Power systems that manage a plurality of power control devices connected to a power system and control the reception of power from the power system are becoming widespread. For example, Patent Documents 1 and 2 disclose an example of a power system that includes a plurality of power control devices (power conditioners) and a processing device (centralized management device). The processing device calculates an induction command value for controlling the value of the connection point power (power to be adjusted) to a target power. Each power control device controls the output power in a distributed manner using the induction command value (index) 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 induction command value. Then, the output power is controlled so that the output power becomes the target value. In this manner, energy management of the power system is performed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-165552 A [Patent Document 2] JP 2020-150690 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a conventional power system, the processing device calculates an induction command value by a calculation using the difference (P-Pc) between the connection point power value P and the target power value Pc. In this configuration, if the number of connected power control devices is small, it may take a long time for the connection point power value to reach the target power. In other words, in a conventional power system, if the number of power control devices is small, the response characteristics until the connection point power value reaches the target power may be poor.

[0005] The present disclosure has been devised in consideration of the above circumstances, and its purpose is to provide a power system that can improve the response characteristics until the connection point power value becomes the target power, even if the number of power control devices is small. [Means for solving the problem]

[0006] The power system provided by the present disclosure is a power system that controls a value of a connection point power at a connection point with a power grid to a system target value, and includes at least one power control device to which power devices are connected and which controls the output of the connected power devices, and a processing device capable of communicating with the at least one power control device, the processing device including a first acquisition unit that acquires the value of the connection point power, a second acquisition unit that acquires the system target value, a command value calculation unit that calculates an induced command value for setting the value of the connection point power to the system target value, and a transmission unit that transmits the induced command value to the at least one power control device, Each power control device includes a receiving unit that receives the induced command value, a target calculation unit that uses the induced command value to calculate an equipment target, which is a target value for the output of the connected power equipment, and a power control unit that controls the connected power equipment so that its output becomes the equipment target, and the command value calculation unit includes a first compensator that receives as input the connection point power value and the system target value and outputs a first command value, a second compensator that receives as input the system target value and outputs a second command value, and an adder that adds the first command value and the second command value to output the induced command value common to the at least one power control device.

[0007] In a preferred embodiment of the power system, each of the at least one power control device is a controlled object in which the induced command value is an input signal and the output of the connected power equipment is an output signal, and the second compensator includes a transfer function in which the system target value is an input signal and the second command value is an output signal, and the transfer function includes a control gain in any one of the at least one power control device.

[0008] In a preferred embodiment of the power system, the at least one power control device is provided with a plurality of power control devices, and the transfer function includes a control gain of at least one of the plurality of power control devices as a target.

[0009] In a preferred embodiment of the power system, the control gain includes a first gain in the target calculation unit and a second gain in the power control unit, and the transfer function is expressed by the following equation (1), where the number of the multiple power control devices is n (n is a positive integer greater than or equal to 2), the transfer function is G(s), the first gain of the i-th power control device (i is a positive integer less than or equal to n) is Wi, and the second gain of the i-th power control device is Ji.

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[0010] In a preferred embodiment of the power system, the first gain is the same for each of the multiple power control devices, while the second gain is the same for each of the multiple power control devices, the processing device includes a number acquisition unit that acquires the number of the multiple power control devices, and the command value calculation unit includes a second compensator adjustment unit that adjusts the transfer function of the second compensator in accordance with the number. Effect of the Invention

[0011] The power system of the present disclosure performs power control of the connection point power using an induction command value that is the sum of the first command value and the second command value. With this configuration, it is possible to suppress a delay in the response characteristic until the value of the connection point power reaches the system target value (target power), which occurs when operating with a small number of power control devices. In other words, the power system of the present disclosure can improve the response characteristic until the value of the connection point power reaches the system target value, when operating with a small number of power control devices. [Brief description of the drawings]

[0012] [Figure 1] 1 is a diagram illustrating an example of the overall configuration of a power system according to a first embodiment. [Diagram 2] FIG. 2 is a block diagram showing power control of the power system of FIG. 1. [Diagram 3] This is the result of simulating the change in connection point power during power control of a comparison power system (a conventional power system). [Figure 4] 13 is a result of simulating a change in connection point power in power control assuming that there is one operating power control device in the power system according to the first embodiment. [Diagram 5] 13 is a result of simulating a change in connection point power in power control assuming that there are two operating power control devices in the power system according to the first embodiment. [Figure 6] FIG. 11 is a diagram illustrating a processing device of a power system according to a second embodiment. [Figure 7] FIG. 11 is a block diagram showing power control of a power system according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the power system of 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.

[0014] Fig. 1 shows a power system S1 according to the first 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 a power receiving facility C1.

[0015] The power system S1 is connected to the power system D via a connection point K. The power system S1 is capable of receiving power from the power system D. The power system S1 may be capable of transmitting power to the power system D (capable of reverse power flow), or may not be capable of transmitting power (not capable of reverse power flow). In the present disclosure, when power is being output from the power system S1 to the power system D, i.e., when reverse power flow is occurring, the connection point power is assumed to be a positive value. On the other hand, when power is being output from the power system D to the power system S1, the connection point power is assumed to be a negative value. The connection point power refers to the power at the connection point K between the power system S1 and the power system D.

[0016] The power system S1 performs power control in cooperation with the processing device A1 and the multiple power control devices B1 so that the value of the connection point power becomes the target value of the connection point power (hereinafter referred to as the "system target value"). Examples of power control performed by the power system S1 include output suppression control, peak cut control, reverse flow avoidance control, and schedule control. In output suppression control, the power (sold power) output from the power system S1 to the power system D is suppressed in accordance with an output suppression command issued by the power company. In peak cut control, the peak value of the power (purchased power) supplied from the power system D is suppressed. In reverse flow avoidance control, the occurrence of reverse flow is suppressed. In schedule control, the output power of the power system S1 is set to a power value set by the user. The power system S1 performs one of these power controls depending on the control mode set in the processing device A1. Note that the control mode is not limited to the above examples.

[0017] The power loads L consume the supplied power. The power loads L are supplied with power from the power system D and each power control device B1. The power loads L include general loads and / or important loads. The general loads are, for example, electrical equipment that is relatively unaffected even if the power is cut off during a disaster, such as air conditioning equipment. The important loads are important loads that require a continuous supply of power even during a disaster, such as emergency elevators, electrical equipment that requires continuous operation, and building lighting.

[0018] The power line 90 constitutes a power network in the power system S1. The power system S1 is connected to an electric power grid D by the power line 90.

[0019] The power receiving equipment C1 is configured to include a switchboard and a distribution board. The power receiving equipment C1 also includes various protection devices for connecting the power system S1 to the power system D. For example, if the power system S1 is a system in which reverse power flow to the power system D is prohibited, a reverse power relay is included as a protection device. The power receiving equipment C1 receives power input from the power system D and each power control device B1 via a power line 90. The power receiving equipment C1 appropriately supplies the received power to the power system D, each power control device B1, power load L, etc. The power receiving equipment C1 is capable of communicating with the processing device A1.

[0020] 1, the power receiving equipment C1 includes a measurement unit 31 and a communication unit 32. The measurement unit 31 is installed at a connection point K between the power system S1 and the power grid D, and detects the connection point power. The measurement unit 31 is, for example, a power transducer. The communication unit 32 transmits the measurement result of the measurement unit 31, i.e., the measurement value of the connection point power, to the processing device A1.

[0021] The processing device A1 can communicate with each of the multiple power control devices B1 and the power receiving equipment C1. These communications may be wireless or wired. The processing device A1 monitors the connection point power and calculates an induction command value for controlling the value of the connection point power to a system target value. As shown in FIG. 1, the processing device A1 includes a first acquisition unit 11, a second acquisition unit 12, a command value calculation unit 13, a receiving unit 14, and a transmitting unit 15.

[0022] The first acquisition unit 11 acquires a value of the connection point power. In the present embodiment, the first acquisition unit 11 acquires the value of the connection point power by receiving a measurement value of the connection point power from the power receiving equipment C1 via the receiving unit 14.

[0023] The second acquisition unit 12 acquires a system target value. For example, the second acquisition unit 12 acquires the system target value by receiving the system target value from a computer (not shown) of a power company or a computer (not shown) that inputs the settings of the processing device A1 via the receiving unit 14. Alternatively, the second acquisition unit 12 may acquire the target power by reading out a system target value stored in a storage unit (not shown) provided in the processing device A1. The second acquisition unit 12 acquires a system target value according to a control mode set in the processing device A1.

[0024] The command value calculation unit 13 calculates a guide command value using the value of the connection point power acquired by the first acquisition unit 11 and the system target value acquired by the second acquisition unit 12. The command value calculation unit 13 includes a first compensator 131, a second compensator 132, and an adder 133.

[0025] The first compensator 131 receives the connection point power value and the system target value. The first compensator 131 calculates the first command value Y1 using the input connection point power value and the system target value. For example, the first compensator 131 calculates the first command value Y1 by solving state equations (simultaneous differential equations) shown in the following formulas (2) and (3). In the following formulas (2) and (3), Px(t) is the connection point power value, Pt(t) is the system target value, λ is a state variable, and ε is a gradient coefficient. This state equation is set in the first compensator 131. The first compensator 131 calculates the first command value Y1 at predetermined time intervals (for example, 1 [sec]). The first command value Y1 is a command value for making the connection point power value the system target value.

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[0026] The second compensator 132 receives a system target value as input. The second compensator 132 calculates a second command value Y2 using the input system target value. An example of the calculation of the second command value by the second compensator 132 will be described later. The second command value Y2 is a command value for setting the value of the connection point power to the system target value.

[0027] The first command value Y1 and the second command value Y2 are input to the adder 133. The adder 133 calculates the induced command value pr by adding the input first command value Y1 and second command value Y2.

[0028] The receiver 14 receives a measurement value of the connection point power from the power receiving equipment C1 through communication with the power receiving equipment C1. The receiver 14 also receives system target values ​​from each of the above-mentioned computers. The transmitter 15 transmits the induced command value calculated by the command value calculator 13 through communication with the multiple power control devices B1. The transmitter 15 transmits the induced command value to the multiple power control devices B1 by, for example, multicast, but may also transmit by broadcast (simultaneous transmission) or unicast.

[0029] A power device X is connected to each of the power control devices B1. Each power control device B1 controls the output of the connected power device X. Each of the power control devices B1 can communicate with the processing device A1. The power device X is, for example, a solar cell, a storage battery, an electric vehicle, or a generator, as in the power system described in Patent Document 2. In the power system S1, each of the power control devices B1 is either a solar power conditioner, a storage battery power conditioner, an EV (Electric Vehicle) stand, or a generator control device. For example, all of the power control devices B1 may be configured with a solar power conditioner or a storage battery power conditioner. In addition, the power control devices B1 may be configured with at least one solar power conditioner and at least one storage battery power conditioner. In other words, the power control devices B1 may include any one of a solar power conditioner, a storage battery power conditioner, an EV stand, and a generator control device. The solar power conditioner is a power control device to which a solar cell is connected as the power device X and controls the power generated by the solar cell. The storage battery power conditioner is a power control device to which a storage battery is connected as the power device X and controls the charging and discharging of the storage battery. The EV stand is a power control device to which an electric vehicle is connected as the power device X and controls the charging and discharging of the electric vehicle. The generator control device is a power control device to which a generator is connected as the power device X and controls the power generated by the generator. The multiple power control devices B1 may also include a load control device that uses a power load L as the power device X, similar to the power system described in Patent Document 2.

[0030] As shown in FIG. 1, each of the plurality of power control devices B1 includes a receiving unit 21, a target calculation unit 22, and a power control unit .

[0031] The receiving unit 21 receives the guiding command value pr transmitted from the processing device A1. The receiving unit 21 outputs the received guiding command value pr to the target calculation unit 22.

[0032] The target calculation unit 22 calculates a target value of the output of the corresponding power device X (hereinafter, “device target P ref The induction command value pr is calculated based on the equipment target P ref This optimization problem includes an evaluation function and constraint conditions. The evaluation function is the same as that described in Patent Document 2, for example, and is the following formulas (4) and (5). In this embodiment, the target calculation unit 22 performs the calculations of the following formulas (6) and (7) derived from the evaluation functions shown in the following formulas (4) and (5), as described in Patent Document 2. In the following formulas (4) to (7), pr lmt is the induction command limit, and a1 to a4 are design parameters. lmt and the design parameters a1 to a4 are the same as those described in Patent Document 2. As described in Patent Document 2, the calculation results are corrected by the constraint conditions to obtain the equipment target P ref The constraint conditions are the same as those described in Patent Document 2. In contrast, the target calculation unit 22 calculates the equipment target P by solving the evaluation function under the constraint conditions. ref In addition, the induction command value limit pr lmt By setting the above design parameters a1 to a4, the evaluation functions shown in the following formulas (4) and (5) become the evaluation function shown in the following formula (8) set for the power conditioner for solar cells described in Patent Document 1, or the evaluation function shown in the following formula (9) set for the power conditioner for storage batteries described in Patent Document 1. Note that in the following formula (8), P ref PVi is the equipment target P for a solar cell power conditioner. ref And pr PV is the induction command value in the solar cell power conditioner, and W PVi is the weight for suppressing the active power of the solar cell power conditioner, and P φi is a priority parameter, which is the same as that described in Patent Document 1. In the following formula (9), P ref Bkis the equipment target P for the power conditioner for the storage battery ref And pr B is the induction command value in the power conditioner for the storage battery, and W Bk is the weight of the active power of the power conditioner for the battery, and W SOCk are weights according to the SOC (State Of Charge) of the connected storage battery, and are the same as those described in Patent Document 1. The induction command value calculated by the target calculation unit 22 is output to the power control unit 23.

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[0033] The power control unit 23 outputs the output power of the corresponding power device X (hereinafter, “device power P out ") is the equipment target P ref The power P of the power device X is out For example, in a power control device B1 to which a solar cell is connected as the power device X, the power control unit 23 controls the device target P ref In the power control device B1 to which a storage battery is connected as the power device X, the power control unit 23 controls the power generation of the solar cell based on the device target P ref In the power control device B1 to which an electric vehicle is connected as the power device X, the power control unit 23 controls the charging power and discharging power of the storage battery based on the device target P ref In the power control device B1 to which a generator is connected as the power device X, the power control unit 23 controls the charging power and discharging power of the electric vehicle based on the device target P ref In the power control device B1 (load control device) that manages the power load L, the power control unit 23 controls the power generated by the generator based on the equipment target P ref Based on this, the power consumption of the power load L is controlled.

[0034] In the power system S1 configured as above, each power control device B1 uses the induction command value received from the processing device A1 to set the device target P refThen, each power control device B1 calculates the calculated device target P ref The device power P out In this manner, in the power system S1, a plurality of power control devices B1 control the output power in a distributed manner, so that the value of the connection point power becomes the system target value.

[0035] Next, power control in the power system S1 will be described with reference to the block diagram shown in Fig. 2. In the example shown in Fig. 2, the power system S1 includes n (n is a positive integer) power control devices B1 as the multiple power control devices B1. The specifications (functions, performance, connected power devices X, etc.) of the n power control devices B1 are assumed to be the same as each other. In the following description, s denotes the Laplace operator.

[0036] The power system S1 performs power control using the processing device A1 as a controller, each of the multiple power control devices B1 as a control object, the node power Px as a control variable, the system target value Pt as a set value, and the induction command value pr as a manipulated variable.

[0037] In each power control device B1, the target calculation unit 22 receives the induction command value pr and calculates the equipment target P ref The target calculation unit 22 outputs the induction command value pr as the equipment target P ref The transfer function H1(s) converts the induction command value pr into the equipment target P ref is the output signal. The gain W of the transfer function H1(s) is found by partially differentiating the above-mentioned evaluation function set in the target calculation unit 22. For example, in an example in which the connected power device X is a solar cell and the evaluation function of the above-mentioned formula (8) (formula 11a in Patent Document 1) is set in the target calculation unit 22, the gain W of the transfer function H1(s) is calculated by: φi -(1 / 2W PVi In addition, in an example in which the connected power device X is a storage battery and the evaluation function of the above formula (9) is set in the target calculation unit 22, the gain W of the transfer function H1(s) is 1 / 2W Bk W SOCk It is.

[0038] In each power control device B1, the power control unit 23 sets the device target P ref is input, and the device power P out The power control unit 23 outputs the device target P ref The device power P out The transfer function H2(s) converts the instrument target P ref is the input signal, and the device power P out In this embodiment, the power control unit 23 outputs the device power P out is the equipment target P ref Since power is controlled so that: the gain J is, for example, 1. Unlike this example, when the equipment target is a current value, the input is a current value and the output is power, so the gain J is a set voltage V. Note that a current value is input as the equipment target to the power control unit 23, and the power control unit 23 controls the output current of the inverter in the power control unit 23 based on this current value. At this time, the inverter outputs equipment power P out Therefore, even if the device target is a current value, the output signal of the power control unit 23 is the device power P out It can be regarded as:

[0039] Each power control device B1 configured as above receives the induction command value pr as an input signal, and controls the device power P out The control gain of the transfer function includes a gain W and a gain J, and is expressed by multiplying the gain W by the gain J (W×J). In this embodiment, the n power control devices B1 have the same specifications (functions, performance, connected power devices X, etc.), so the control gains (gain W and gain J) set in each power control device B1 are the same.

[0040] In the processing device A1, the first compensator 131 receives the system target value Pt and the connection point power Px, and outputs the first command value Y1. As shown in FIG. 2, the first compensator 131 includes a calculator 131a and a controller 131b. The calculator 131a calculates the deviation between the system target value Pt and the connection point power Px by subtracting the connection point power Px from the system target value Pt. The controller 131b includes a transfer function G1(s) that converts the deviation (the value obtained by subtracting the connection point power Px from the system target value Pt) into the first command value Y1. The transfer function G1(s) is the same as that described in, for example, Patent Document 2. That is, the transfer function G1(s) includes a transfer function K(s) and an integral element, and is expressed as G1(s)=K(s) / s.

[0041] In the processing device A1, the second compensator 132 receives the system target value Pt as an input and outputs a second command value Y2. The second compensator 132 includes a transfer function G2(s) that converts the system target value Pt into the second command value Y2. The transfer function G2(s) includes, for example, a control gain (W×J) of at least one of the n power control devices B1, and is expressed as the reciprocal of the sum of the control gains. In particular, the transfer function G2(s) is set to include the control gain of the target power control device B1 in the power control of the power system S1. Therefore, when any one of the multiple power control devices B1 is targeted, the transfer function G2(s) is 1 / (W×J), and when any two of the multiple power control devices B1 are targeted, the transfer function G2(s) is 1 / (2×(W×J))(=1 / ((W×J)+(W×J))). In this embodiment, since the control gain (W×J) set for each power control device B1 is the same, the transfer function G2(s) can be regarded as being set according to the number of operating power control devices B1 that are targets in the power control of the power system S1. In other words, when it is assumed that the number of operating power control devices B1 that are targets is i (i is a positive integer equal to or less than n), the transfer function G2(s) is 1 / (i×(W×J)).

[0042] Next, the results of simulating the change in the connection point power Px in the power control of the power system S1 shown in FIG. 2 will be described with reference to FIG. 3, FIG. 4, and FIG. 5. In the simulations of FIG. 3 to FIG. 5, the control gain of the power control device B1 used is all the same (W×J). In FIG. 3, FIG. 4, and FIG. 5, the horizontal axis is time and the vertical axis is power value. In FIG. 3, FIG. 4, and FIG. 5, the solid line indicates the change in the connection point power Px over time, and the dashed line indicates the change in the system target value Pt over time. Thus, FIG. 3, FIG. 4, and FIG. 5 are simulations of how the connection point power Px changes when the system target value Pt is switched from 0 (zero) to the set value P1 at time t1.

[0043] Fig. 3 shows a result of simulating power control in a configuration in which the command value calculation unit 13 does not include the second compensator 132 and the adder 133. That is, Fig. 3 shows a result of simulating power control in a power system equivalent to the power systems described in Patent Documents 1 and 2, in which the output (first command value Y1) of the first compensator 131 is used as an induction command value. Hereinafter, this power system will be referred to as a comparative power system. Fig. 3(a) shows a case in which one power control device B1 is used, and Fig. 3(b) shows a case in which four power control devices B1 are used.

[0044] In the comparative power system, as shown in Figs. 3(a) and (b), the connection point power Px converges to the system target value Pt whether one power control device B1 is used or four power control devices B1 are used. At this time, the time until the connection point power Px converges to the system target value Pt is approximately time t9 when one power control device B1 is operated, as shown in Fig. 3(a), and approximately time t4 when four power control devices B1 are operated, as shown in Fig. 3(b). Therefore, in the comparative power system, it is found that if the number of power control devices B1 operated is small, the time until the connection point power Px becomes the system target value Pt is long. In other words, it is found that in the comparative power system, if the number of power control devices B1 operated is small, the response characteristic until the value of the connection point power becomes the system target value is low. Note that the "response characteristic" described below refers to the response characteristic until the value of the connection point power becomes the system target value.

[0045] Next, Fig. 4 shows the results of simulating power control in the power system S1 targeting any one of the n power control devices B1. That is, it shows the results of simulating power control in the power system S1 assuming a case where it operates with one power control device B1. In this simulation, the transfer function G2(s) of the processing device A1 (second compensator 132) is 1 / (W x J). Fig. 4(a) shows the case where it operates using one power control device B1, and Fig. 4(b) shows the case where it operates using four power control devices B1. Hereinafter, this power system S1 is referred to as the power system S11.

[0046] In the power system S11, as shown in Figs. 4(a) and (b), the connection point power Px converges to the system target value Pt whether one power control device B1 is used or four power control devices B1 are used. That is, in the power system S11, the connection point power Px converges to the system target value Pt, as in the comparative power system. At this time, the time until the connection point power Px converges to the system target value Pt is approximately time t2 when operated with one power control device B1, as shown in Fig. 4(a), and is between time t3 and time t4 when operated with four power control devices B1, as shown in Fig. 4(b). Therefore, in the power system S11, when operated with one power control device B1, the time until the connection point power Px becomes the system target value Pt can be shortened. That is, it can be seen that the power system S11 can improve the response characteristics when one power control device B1 is operated.

[0047] Next, Fig. 5 shows a result of simulating power control in the power system S1 targeting any two of the n power control devices B1. That is, it shows a result of simulating power control in the power system S1 assuming a case where it operates with two power control devices B1. In the simulation, the transfer function G2(s) of the processing device A1 (second compensator 132) is 1 / (2 x (W x J)). Fig. 5(a) shows a case where it operates using two power control devices B1, Fig. 5(b) shows a case where it operates using three power control devices B1, and Fig. 5(c) shows a case where it operates using four power control devices B1. Hereinafter, this power system S1 is referred to as a power system S12.

[0048] In the power system S12, as shown in Fig. 5(a)-(c), the connection point power Px converges to the system target value Pt, whether two, three, or four power control devices B1 are used. That is, in the power system S12, as in the comparative power system and the power system S11, the connection point power Px converges to the system target value Pt. At this time, the time until the connection point power Px converges to the system target value Pt is approximately time t2 when operating with two power control devices B1, as shown in Fig. 5(a), between time t3 and time t4 when operating with three power control devices B1, as shown in Fig. 5(b), and between time t3 and time t4 when operating with four power control devices B1, as shown in Fig. 5(c). Incidentally, the time until the convergence occurs is between time t3 and time t4 whether three power control devices B1 are used or four power control devices B1 are used, but it is slightly faster when three power control devices B1 are used. Therefore, in the power system S12, when two power control devices B1 are used, the time until the connection point power Px reaches the system target value Pt can be shortened. In other words, it can be seen that the power system S12 can improve the response characteristics when two power control devices B1 are used.

[0049] As described above, from the simulation results shown in Figures 3 to 5, in the power system S1, by including the command value calculation unit 13 in the second compensator 132, it is possible to improve the above-mentioned response characteristics with a smaller number of power control devices B1 compared to a comparative power system (a configuration that does not include the second compensator 132).

[0050] The functions and effects of the power system S1 are as follows.

[0051] In the power system S1, the command value calculation unit 13 includes a first compensator 131 that receives the value of the connection point power and the system target value as inputs and outputs a first command value, a second compensator 132 that receives the system target value as inputs and outputs a second command value, and an adder 133 that adds the first command value and the second command value to calculate an induced command value. According to this configuration, the induced command value of the power system S1 is given by adding the second command value calculated from the system target value to the first command value equivalent to the induced command value described in Patent Document 1. That is, in the power system S1, power is controlled so that the value of the connection point power becomes the system target value by the first command value and the second command value. According to this configuration, as can be understood from the simulation results of each of FIGS. 3 to 5, it is possible to suppress the delay in the response characteristics that occurs when the power system S1 is operated with a small number of power control devices B1. Therefore, the power system S1 can improve the response characteristics when the number of power control devices B1 is small compared to the power systems described in Patent Documents 1 and 2.

[0052] In the power system S1, the transfer function G2(s) set in the processing device A1 (second compensator 132) includes the control gain (gain W and gain J) of the target power control device B1 among the multiple power control devices B1. In this embodiment, since the control gains (gain W and gain J) set in each power control device B1 are the same, the transfer function G2(s) set in the second compensator 132 can be considered to be set according to the number of operating target power control devices B1. With this configuration, as can be understood from the simulation results shown in Figs. 4 and 5, assuming a case where n power control devices B1 are operated, it is possible to improve the response characteristics when n power control devices B1 are operated.

[0053] Next, a power system S2 according to the second embodiment will be described with reference to Fig. 6. Fig. 6 is a block diagram showing a processing device A1 of the power system S2. In the power system S2, the configuration other than the processing device A1 is the same as that of the power system S1. The power system S2 differs from the power system S1 in the following respects. First, the processing device A1 is provided with a number acquisition unit 16. Second, the command value calculation unit 13 includes a second compensator adjustment unit 134.

[0054] The number acquisition unit 16 acquires the number of the multiple power control devices B1. In this embodiment, this number is the number of the power control devices B1 connected to the power system D, but it may be the number of the target power control devices B1, or the number of the power control devices B1 in operation. There is no limitation on the method of acquiring the number performed by the number acquisition unit 16. For example, the processing device A1 may acquire the number by inputting the number to the processing device A1 (a computer that inputs the settings of the above-mentioned processing device A1) by a user, or the processing device A1 may acquire the number by communicating with the multiple power control devices B1.

[0055] The second compensator adjustment unit 134 adjusts the transfer function G2(s) set in the second compensator 132 according to the number of the multiple power control devices B1. For example, when the number of devices acquired by the number acquisition unit 16 is i, the second compensator adjustment unit 134 sets the transfer function G2(s) of the second compensator 132 to 1 / (i×(W×J)). Thus, when the number of devices acquired by the number acquisition unit 16 is 1, the second compensator adjustment unit 134 adjusts the transfer function G2(s) of the second compensator 132 to 1 / (W×J), and when the number of devices acquired by the number acquisition unit 16 is 3, the second compensator adjustment unit 134 adjusts the transfer function G2(s) of the second compensator 132 to 1 / (3×(W×J)).

[0056] As described above, in the power system S2, the transfer function G2(s) set in the second compensator 132 is adjusted according to the number of the power control devices B1. Therefore, in a power system in which the connection and disconnection of the power control device B1 are performed at any time, the transfer function G2(s) is adjusted to a value according to the number of connected devices at that time. For example, in a power control device B1 to which an electric vehicle can be connected as the power device X, the electric vehicle can be connected and disconnected at any time. In other words, in the power system S2, an appropriate transfer function G2(s) is set according to the number of operating power control devices B1 that changes due to the connection and disconnection of each power control device B1, so that the response characteristic can be improved even when the connection status of each power control device B1 changes. In addition, the power system S2 has the same effects as the power system S1 due to the configuration common to the power system S1.

[0057] Next, a power system S3 according to a third embodiment will be described with reference to Fig. 7. Fig. 7 is a block diagram showing power control of the power system S3. The overall configuration of the power system S3 is the same as the overall configuration of the power system S1. The power system S3 differs from the power system S1 in the following respect. That is, the multiple power control devices B1 include those having different set control gains (gain W of the target calculation unit 22 and gain J of the power control unit 23).

[0058] In the power system S3, the first power control device B1 is set with a gain W1 and a gain J1, the second power control device B1 is set with a gain W2 and a gain J2, and the i-th power control device B1 (i is a positive integer equal to or less than n) is set with a gain W i and gain J i is set, and the nth power control device B1 has a gain W n and gain J n These gains W1, W2, . . . , W i ,···,W n are different from each other, and these gains J1, J2, . . . , J i ,···,J nare different from each other. The multiple power control devices B1 may include those having the same control gain. However, any two of the multiple power control devices B1 have different control gains. For example, the gain W2 and gain J2 of the second power control device B1 may be the same as the gain W1 and gain J1 of the first power control device B1, respectively. However, the gain W2 and gain J2 of the second power control device B1 are different from the gain W and gain J of at least one power control device B1 among the power control devices B1 other than the first power control device B1.

[0059] In the power system S3, the transfer function G2(s) set in the second compensator 132 of the processing device A1 includes a control gain set in at least one of the multiple power control devices B1, and is expressed as the reciprocal of the sum of the control gains. Preferably, the power control device B1 is a target for improving the response characteristics. For example, when improving the response characteristics of the i-th power control device B1, the transfer function G2(s) is set to the control gain (gain W i and gain J i ) and is expressed as 1 / (Wi×Ji). In contrast to this example, when improving the response characteristics of the i-th and k-th (k is a positive integer not greater than n and different from i) power control devices B1, the transfer function G2(s) is the control gain (gain W i ,W k and gain J i ,J k ), including 1 / ((W i xJ i )+(W k xJ k When all of the multiple power control devices B1 are targeted, the transfer function G2(s) includes the control gains of all the power control devices B1 and is expressed, for example, as in the following equation (10).

number

[0060] As described above, even if the control gains (gain W and gain J) set in the multiple power control devices B1 are different, the power system S3 can improve the above-mentioned response characteristics by having the transfer function G2(s) include the control gain set in at least one of the multiple power control devices B1. Furthermore, when the transfer function G2(s) includes the control gains of all the power control devices B1, the response characteristics can be improved most in the power system S3. In addition, the power system S3 has the same effects as the power system S1 due to the configuration shared between the power system S1 and the power system S1.

[0061] In the above embodiment, an example was shown in which the measured value measured by the measurement unit 31 was used as the value of the connection point power. Unlike this example, an estimated value obtained by calculation may be used as the value of the connection point power. In this example, the processing device A1 can communicate with each power control device B1 and the power load L, and the first acquisition unit 11 acquires the value of the device power from each power control device B1 (each power control unit 23) and acquires the value of the power consumption from the power load L. Then, the first acquisition unit 11 calculates the estimated value of the connection point power by adding the value of the device power of each power control device B1 and the value of the power consumption of the power load L. Thereby, the first acquisition unit 11 can use the estimated value of the connection point power as the value of the connection point power. Note that the first acquisition unit 11 may be configured to acquire both the measured value of the connection point power and the estimated value of the connection point power, and select whether to use the measured value or the estimated value depending on the control mode to be set.

[0062] The power system according to the present disclosure is not limited to the above-described embodiment. The specific configuration of each part of the power system according to the present disclosure can be freely designed in various ways. [Explanation of symbols]

[0063] S1, S2, S3: power system, A1: processing device, B1: power control device, D: power system, K: connection point, X: power equipment, 11: first acquisition unit, 12: second acquisition unit, 13: command value calculation unit, 131: first compensator, 132: second compensator, 133: adder, 134: second compensator adjustment unit, 14: receiving unit, 15: transmitting unit, 16: number acquisition unit, 21: receiving unit, 22: target calculation unit, 23: power control unit

Claims

1. A power system that controls a value of a connection point power at a connection point with a power grid to a system target value, At least one power control device to which an electric power device is connected and which controls an output of the connected electric power device; a processor capable of communicating with the at least one power control device; Equipped with the processing device includes a first acquisition unit that acquires a value of the connection point power, a second acquisition unit that acquires the system target value, a command value calculation unit that calculates an induction command value for making the value of the connection point power the system target value, and a transmission unit that transmits the induction command value to the at least one power control device; The at least one power control device includes a receiving unit that receives the induced command value, a target calculation unit that uses the induced command value to calculate an equipment target that is a target value of an output of the connected electric power equipment, and a power control unit that controls the connected electric power equipment so that the output of the connected electric power equipment becomes the equipment target, the command value calculation unit includes: a first compensator that receives as input the value of the connection point power and the system target value and outputs a first command value; a second compensator that receives as input the system target value and outputs a second command value; and an adder that adds the first command value and the second command value and outputs the induced command value common to the at least one power control device.

2. Each of the at least one power control device is a controlled object having the induction command value as an input signal and an output of the connected power device as an output signal, the second compensator includes a transfer function in which the system target value is an input signal and the second command value is an output signal; The power system of claim 1 , wherein the transfer function includes a control gain in any one of the at least one power controller.

3. The at least one power control device includes a plurality of power control devices, The power system of claim 2 , wherein the transfer function includes a control gain of at least one of the plurality of power control devices as a target.

4. the control gain includes a first gain in the target calculation unit and a second gain in the power control unit, The power system of claim 3, wherein the transfer function is expressed by the following equation (1), where n (n is a positive integer equal to or greater than 2) is the number of the plurality of power control devices, G(s) is the transfer function, Wi is the first gain of the i-th power control device (i is a positive integer equal to or less than n), and Ji is the second gain of the i-th power control device. [0010]

5. In the plurality of power control devices, the first gains are the same, and the second gains are the same, the processing device includes a number acquisition unit that acquires the number of the plurality of power control devices; The power system according to claim 4 , wherein the command value calculation unit includes a second compensator adjustment unit that adjusts the transfer function of the second compensator in accordance with the number of power sources.

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