Electric power system

Abstract

To provide an electric power system capable of reducing a calculation load of a processing device.SOLUTION: An electric power system S1 is connected to an electric power system D, and outputs a primary adjustment force. The electric power system S1 comprises: an electric power control device B1; and a processing device A1. The processing device A1 contains: a first acquisition part 11 that acquires a value of a connection point electric power; a second acquisition part 12 that acquires a whole target; and a generation part 13 that generates control information by using a value of a connection point electric power and a whole target. The electric power control device B1 contains: an adjustment width calculation part 22 that calculates an adjustment width; a control value calculation part 23 that calculates a prior adjustment control value by adding the adjustment width to control information; a command value calculation part 24 that calculates an induction command value by using the prior adjustment control value; a reference value calculation part 25 that calculates an output reference value by using the induction command value; a target calculation part 26 that calculates a mechanical target by adding the adjustment width to the output reference value; and an electric power control part 27 that controls an electric power device X so that an output electric power of the electric power control device B1 becomes a device target.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 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 an induction command value for controlling a predetermined adjustment target power to a target power. Each power control device controls output power in a distributed manner using the induction 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 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 2020-150690 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the power system described in Patent Document 1, each of the multiple power control devices individually calculates the target value of the output power using an induced command value. This eliminates the need for the processing device to calculate the target value of the output power of each power control device, thereby reducing the calculation load of the processing device. Even in such a power system, there is still room for improvement in reducing the calculation load of the processing device.

[0005] The present disclosure has been devised in view of the above circumstances, and has an object to provide a power system that can reduce the calculation load on a processing device. [Means for solving the problem]

[0006] The power system of the present disclosure is a power system that is connected to a power grid and provides primary control power to the power grid, the power system comprising: a power control device that is connected to the power grid via a connection point and controls output of connected power equipment; and a processing device capable of communicating with the power control device, wherein connection point power that is power at the connection point includes the primary control power and a system power that is output power of the power system when the primary control power is not provided, and the processing device includes a first acquisition unit that acquires a value of the connection point power, a second acquisition unit that acquires an overall target that is a target value of the system power, a generation unit that generates control information using the value of the connection point power and the overall target, and a processing device that outputs the control information to the power control device. the power control device includes a transmission unit that transmits the control information to a power control device, and the power control device includes: an adjustment range calculation unit that calculates an adjustment range, which is a power value to be adjusted for providing the primary control capacity; a receiving unit that receives the control information; a control value calculation unit that calculates a pre-adjustment control value by adding the adjustment range to the control information; a command value calculation unit that calculates an induced command value using the pre-adjustment control value; a reference value calculation unit that calculates an output reference value for making the system power the overall target, using the induced command value; a target calculation unit that calculates an equipment target, which is a target value for the output power of the power control device, by adding the adjustment range to the output reference value; and a power control unit that controls the power equipment so that the output power of the power control device becomes the equipment target.

[0007] In a preferred embodiment of the power control device, the generation unit generates the difference between the connection point power and the overall target as the control information, the control value calculation unit calculates the pre-adjustment control value by subtracting the adjustment range from the control information, and the target calculation unit calculates the equipment target by adding the adjustment range to the output reference value.

[0008] In a preferred embodiment of the power control device, the power control device includes a filter unit that removes fluctuation components that are steeper than frequency fluctuations in the primary control capacity, and the adjustment range calculation unit outputs the adjustment range to the control value calculation unit via the filter unit.

[0009] In a preferred embodiment of the power control device, the adjustment range calculation unit measures a frequency of the output voltage of the power control unit as an output frequency, and calculates the adjustment range using a frequency deviation of the output frequency from a reference frequency.

[0010] In a preferred embodiment of the power control device, a storage battery is connected as the power device, and the power control device controls charging and discharging of the storage battery. Effect of the Invention

[0011] According to the power system of the present disclosure, since each of the multiple 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 calculation load of the processing device. [Brief description of the drawings]

[0012] [Figure 1] 1 is a diagram illustrating an example of an overall configuration of a power system according to an embodiment. [Diagram 2] 2 is a block diagram showing an example of the configuration of a processing device, a power control device, and a power receiving facility of the power system shown in FIG. 1. [Diagram 3] 11 is a diagram showing simulation results of power control performed by a power control device of a power system according to the present disclosure and a comparative power control device. FIG. [Figure 4] 10 is a block diagram showing configuration examples of a processing device, a power control device, and a power receiving facility of a power system according to a first modified example. FIG. [Diagram 5] 13 is a block diagram showing an example configuration of a processing device, a power control device, and a power receiving facility of a power system according to a second modification. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment 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] 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 power control device 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 is also capable of transmitting power to the power system D (capable of reverse power flow). In this 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] In the power system S1, the processing device A1 and the power control device B1 cooperate with each other to perform power control so that the system power, which is the output power of the power system S1, becomes the target value of the system power (hereinafter referred to as the "overall target"). 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 output (sold power) 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.

[0017] Moreover, the power system S1 adjusts the output power to the power system D in response to the frequency fluctuation of the voltage at the connection point K, thereby providing the power system D with primary control capability. When the balance between the demand and supply of power (supply and demand balance) is lost in the power system D, the voltage frequency of the power system D fluctuates. For example, when the demand exceeds the supply in the power system D, the frequency of the power in the power system D decreases. In this case, the power system S1 adjusts the supply and demand balance of power by increasing the power supplied to the power system D, thereby suppressing a decrease in the voltage frequency in the power system D. On the other hand, when the demand in the power system D falls short of the supply, the frequency of the power in the power system D increases. In this case, the power system S1 adjusts the supply and demand balance of power by decreasing the power supplied to the power system D, thereby suppressing an increase in the voltage frequency in the power system D. The primary control capability is power that is adjusted in response to frequency fluctuations in order to adjust the supply and demand balance of power. In the present disclosure, the frequency fluctuation that occurs in response is a "very short-period" fluctuation, which is, for example, a demand fluctuation of several seconds to several minutes. Therefore, the power system S1 adjusts the supply and demand balance of the power grid D by providing a primary regulation reserve in response to the frequency fluctuation of the voltage at the connection point K.

[0018] The power system S1 trades with a supply and demand adjustment market (not shown) by using a trading system (not shown) to trade primary control capacity. The supply and demand adjustment market is operated by, for example, a general electricity transmission and distribution company. In the supply and demand adjustment market, the time is divided into blocks of, for example, three hours (from 0:00 to 3:00, from 3:00 to 6:00, ..., from 21:00 to 24:00), and the control capacity (ΔkW) of each three-hour unit is traded as a product block. Note that the above three-hour unit time is an example, and may be changed according to the regulations of the supply and demand adjustment market. When a transaction with the supply and demand adjustment market is established, the power system S1 provides primary control capacity to the power system D in the product block in which the transaction is established. Note that the power system S1 does not provide primary control capacity in time periods other than the product block in which the transaction is established. In a product block for which a transaction has been concluded, the power system S1 performs power control so that the system power becomes the overall target, while also performing control to provide primary control reserve. Therefore, in a product block for which a transaction has been concluded, the connection point power includes system power and primary control reserve. In a time period other than the product block for which a transaction has been concluded, the power system S1 performs power control so that the system power becomes the overall target, and does not perform control to provide primary control reserve. Therefore, in a time period other than the product block for which a transaction has been concluded, the connection point power includes system power, but does not include primary control reserve.

[0019] The power load L consumes the supplied power. The power load L is supplied with power from the power system D and the power control device B1. The power load L includes general loads and important loads. The general load is, for example, an electrical device that is relatively unaffected even if the power is cut off during a disaster, such as an air conditioning device. The important load is an important load that requires a continuous supply of power even during a disaster, such as an emergency elevator, electrical devices that require continuous operation, and building lighting.

[0020] 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.

[0021] 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 grid D. The power receiving equipment C1 receives power input from the power grid D, the power control device B1, and the power load L via the power line 90. The power receiving equipment C1 supplies the received power to the power grid D, the power control device B1, the power load L, etc. The power receiving equipment C1 is capable of communicating 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 a connection point K between the power system S1 and the power grid D, and detects the connection point power. The connection point power is power in which primary control capability is 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, i.e., the measurement value of the connection point power, to the processing device A1.

[0023] The processing device A1 generates information (control information described later) for the power control device B1 to control the output power. The processing device A1 can communicate with the power control device B1 and the power receiving equipment C1. This communication may be wireless or wired. 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, and a transmission unit 15.

[0024] The first acquisition unit 11 acquires the connection point power. In the present embodiment, the first acquisition unit 11 receives a measurement value of the connection point power from the power receiving equipment C1 via the receiving unit 14, thereby acquiring the value (measurement value) of the connection point power.

[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 (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 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 according to the control mode set in the processing device A1.

[0026] The generating unit 13 generates control information using the measurement value of the connection point power acquired by the first acquiring unit 11 and the overall target acquired by the second acquiring unit 12. In this embodiment, the generating unit 13 generates the difference between the measurement value of the connection point power and the overall target as the control information. In other words, the control information includes a difference value ΔP which is the difference between the measurement value of the connection point power and the overall target. In this 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 receiver 14 receives the 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 the overall target from each of the above-mentioned computers. The transmitter 15 transmits control information through communication with the power control device B1.

[0028] The power control device B1 is connected to an electric power device X connected to the power receiving facility C1, and controls the output of the electric power device X. In this embodiment, as shown in FIG. 1, the power control device B1 is connected to a storage battery BT as the electric power device X, and controls charging and discharging of the storage battery BT. In this embodiment, the 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 electric power device X (storage battery BT) is connected to the power control device B1 (storage battery PCS), but multiple electric power devices X (storage batteries BT) may be connected. The storage battery BT may be, for example, a secondary battery such as a lithium ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, or a lead storage battery, or a capacitor such as an electric double layer capacitor. The power control device B1 (storage battery PCS) supplies power input from the power receiving facility C1 to the storage battery BT connected thereto, thereby charging the storage battery BT. The power control device B1 (storage battery PCS) also outputs the power stored in the connected storage battery BT to the power receiving equipment C1, thereby discharging the storage battery BT. The power control device B1 (storage battery PCS) controls the charge and discharge amounts of the connected storage battery BT, thereby controlling the output power of the storage battery BT.

[0029] In the present disclosure, the power control device B1 is not limited to a storage battery PCS, and may be, for example, a solar PCS to which a solar cell is connected as the power device X, an EV stand to which an electric vehicle is connected as the power device X, a generator control device to which a generator is connected as the power device X, or a load control device to which a power load L is connected as the power device X. The solar PCS controls the amount of power generated by the solar cell. The electric vehicle in the present disclosure refers to a vehicle that can run using an electric motor as a power source, and includes a vehicle (e.g., a plug-in hybrid vehicle) equipped with an internal combustion engine. The electric motor operates using power stored in a storage battery provided in the electric vehicle. The EV stand controls the charging and discharging of the electric vehicle. The generator converts thermal energy of fuels such as oil, coal, and gas into mechanical energy and generates power using this mechanical energy. The generator may be a power generation device that uses renewable energy other than solar energy (e.g., wind power, hydroelectric power, biomass, geothermal heat, etc.). While a solar cell directly converts solar energy into electrical energy, a 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 amount of power generated by the generator. The load control device controls the power load L connected to the power receiving equipment C1, and is, for example, a building energy management system (BEMS) or a factory energy management system (FEMS).

[0030] The power control device B1 controls the output power based on the control information received from the processing device A1. This output power control includes power control for making the system power an overall target (hereinafter referred to as "system power control") and power control for providing primary control capability (hereinafter referred to as "primary control capability control"). The power control device B1 performs system power control and primary control capability control in a product block for which a transaction has been concluded. On the other hand, the power control device B1 performs only system power control (does not perform primary control capability control) in a time period other than the product block for which a transaction has been concluded. In the primary control capability control, the 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 a frequency specified in the power system D, and is, for example, 50 Hz in eastern Japan and 60 Hz in western Japan. Then, the output power is adjusted according to the calculated frequency deviation so that the frequency deviation is reduced.

[0031] The power control device B1 (storage battery PCS) includes a receiving unit 21, an adjustment width calculating unit 22, a control value calculating unit 23, a command value calculating unit 24, a reference value calculating unit 25, a target calculating unit 26, and a power control unit 27, as shown in FIG.

[0032] The receiving unit 21 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 21 is output to the control value calculation unit 23.

[0033] The adjustment range calculation unit 22 calculates an adjustment range, which is a power value adjusted for the provision of primary control capacity. Since the power control device B1 reduces the frequency deviation by providing primary control capacity, the adjustment range is the magnitude of the power adjusted to reduce the frequency deviation at the output end of the power control unit 27. The adjustment range (absolute value) can also be said to be a control target of the primary control capacity in the primary control capacity control. The adjustment range calculation unit 22 calculates an adjustment range according 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 control capacity control. Therefore, the adjustment range is not calculated (or the adjustment range is set to 0) in time periods other than the commodity block in which the transaction is concluded. The adjustment range calculation unit 22 outputs the calculated adjustment range to the control value calculation unit 23.

[0034] For example, the adjustment range calculation unit 22 calculates the 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 device (not shown). Next, the adjustment range calculation unit 22 calculates the frequency deviation of the output frequency from the aforementioned reference frequency (output frequency-reference frequency). The reference frequency is stored in advance in the adjustment range calculation unit 22. Next, the adjustment range calculation unit 22 calculates the adjustment range according to the frequency deviation.

[0035] When the demand exceeds the supply in the power system D, the frequency of the power in the power system D decreases. Therefore, the measured output frequency value becomes smaller than the reference frequency, and 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 adjustment width to increase the output power of the power control unit 27. On the other hand, when the demand falls below the supply in the power system D, the frequency of the power in the power system D increases. Therefore, the measured output frequency value becomes larger than the reference frequency, and 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 adjustment width to decrease the output power of the power control unit 27. Furthermore, when the demand and supply match in the power system D, the measured output frequency value becomes the same as the reference frequency, and the calculated frequency deviation (output frequency-reference frequency) becomes 0 (zero). When the calculated frequency deviation is 0 (zero), adjustment width calculation section 22 sets the adjustment width to 0 (zero), for example, in order to maintain the current output power of power control section 27.

[0036] The adjustment range calculation unit 22 may calculate the adjustment range by taking into consideration predetermined setting items in addition to the frequency deviation. The predetermined setting items include the adjustment ratio, the reference frequency, the rated output and the reference frequency of the power control unit 27, etc. These setting items may be stored in advance in the adjustment range calculation unit 22, or may be acquired from other components as necessary. The adjustment range calculation unit 22 calculates the adjustment range by, for example, performing the calculation of the following formula (1). In the following formula (1), P ctl_t is the adjustment width, dF is the frequency deviation (preferably an upper limit-constrained frequency deviation), Pc is the rated output of the power control unit 27, and F ref is the reference frequency, and R is the adjustment ratio. In this way, by taking into account the above-mentioned setting items, the adjustment width can be calculated with higher accuracy. Note that the setting items are not limited to the above-mentioned example. Also, the calculation performed by the adjustment width calculation unit 22 is not limited to the following formula (1).

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[0037] The control value calculation unit 23 calculates the pre-adjustment control value by adding the adjustment range to the control information. In this embodiment, the receiving unit 21 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 adjustment range from the difference value ΔP. In other words, the pre-adjustment control value = difference value ΔP - adjustment range.

[0038] The command value calculation unit 24 calculates a induced command value using the pre-adjustment control value. The induced command value is a value for the power control device B1 to calculate an output reference value described later. For example, the command value calculation unit 24 calculates a induced command value pr(t) by solving state equations (simultaneous differential equations) shown in the following formulas (2) and (3). In the following formulas (2) and (3), Px is a pre-adjustment control value (ΔP-adjustment width), λ(t) is a state variable, pr(t) is a induced command value, and ε is a gradient coefficient. This state equation is set in the power control device B1. The command value calculation unit 24 calculates the induced command value at predetermined time intervals (for example, 1 [sec]). The induced command value calculated by the command value calculation unit 24 is output to the reference value calculation unit 25.

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[0039] The reference value calculation unit 25 calculates a reference value (output reference value) of the output power of the corresponding power device X based on an optimization problem using the induced command value. The output reference value is the value of the output power expected when individual output adjustment (adjustment in the primary control capability) according 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 the same as that described in Patent Document 1, for example. In this embodiment, the reference value calculation unit 25 performs the calculations of the following equations (4) and (5) derived from the evaluation function, as described in Patent Document 1. In the following equations (4) and (5), P ref is the output reference value of the power control device B1, pr is the induction command value, pr lmtis the induction command limit, and a1 to a4 are design parameters. lmt and design parameters a1 to a4 are the same as those described in Patent Document 1. Then, as described in Patent Document 1, the calculation result is corrected by the constraint conditions to calculate the output reference value. The constraint conditions are the same as those described in Patent Document 1. Alternatively, the reference value calculation unit 25 may calculate the output reference value by solving an 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.

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[0040] The target calculation unit 26 calculates the device target by taking the adjustment range into account in the output reference value. The device target is a target value of the output power of the corresponding power device X. In this embodiment, the target calculation unit 26 calculates the device target by adding the adjustment range to the output reference value. In other words, device target = output reference value + adjustment range. The device target calculated by the target calculation unit 26 is output to the power control unit 27.

[0041] The power control unit 27 controls the device power of the corresponding power device X so that the output power of the power device X (hereinafter referred to as "device power") becomes the device target. Therefore, in an example where the power control device B1 is a storage battery PCS, the power control unit 27 controls the charging power and discharging power of the storage battery BT as the power device X based on the device target. For example, the power control unit 27 discharges the storage battery BT when the device target is a positive value, and charges the storage battery BT when the device target is a negative value. In an example where the power control device B1 is a solar PCS, the power control unit 27 controls the power generation power of a solar battery as the power device X based on the device target. In an example where the power control device B1 is an EV stand, the power control unit 27 controls the charging power and discharging power of an electric vehicle as the power device X based on the device target. In an example where the power control device B1 is a generator control device, the power control unit 27 controls the power generation power of a generator as the power device X based on the device target. In an example where the power control device B1 is a load control device, the power control unit 27 controls the power consumption of a power load L as the power device X based on the device target.

[0042] In the power system S1 configured as above, the processing device A1 acquires the value of the connection point power and the overall target, and generates control information (in this embodiment, the difference value ΔP). Then, the processing device A1 transmits the control information to the power control device B1. The power control device B1 calculates a pre-adjustment control value by adding an adjustment range to the control information received from the processing device A1. In this embodiment, the power control device B1 calculates a pre-adjustment control value by subtracting the adjustment range from the difference value ΔP. Then, using the calculated pre-adjustment control value, the power control device B1 calculates an induction command value according to a preset state equation (the above formula (2) and the above formula (3)). Using the calculated induction command value, the power control device B1 calculates an output reference value of the power device X to be controlled based on a preset optimization problem, and calculates a device target by adding an adjustment range to the output reference value. In this embodiment, the power control device B1 adds the adjustment range to the output reference value to calculate a device target. Then, the output power is controlled so that the output power of the power device X to be controlled becomes the device target. As a result, the power system S1 controls the output power so as to reduce the frequency deviation while setting the system power as an overall target. In other words, the power system S1 provides primary regulation reserve in response to frequency fluctuations while performing power control to set the system power as an overall target.

[0043] FIG. 3 shows a simulation result showing power control in the power control device B1 of this embodiment, where FIG. 3(a) shows the change in the induction command value in this simulation, and FIG. 3(b) shows the change in the control information (difference value ΔP). Note that FIG. 3 also shows the simulation result of a power control device that does not take into account the adjustment range as a comparison target. This comparison target power control device that does not take into account the adjustment range corresponds to a configuration that does not have the control value calculation unit 23, for example. In each of FIGS. 3(a) and (b), the solid line shows the result of the power control device B1 that takes into account the adjustment range, and the dashed line shows the result of the comparison target power control device that does not take into account the adjustment range. Note that in the simulation, it was assumed that a primary control capacity of 40 kW was provided in a case where the power consumption of the power load L was 200 kW and the overall target was 100 kW.

[0044] As shown in FIG. 3(a), the induction command value converges to a certain value in both the power control device B1 and the compared power control device. Therefore, in the power control device B1, the induction command value does not diverge, but converges to a certain value, as in the compared power control device. However, the induction command value pr1 (converged induction command value) of the power control device B1 indicates a lower value than the induction command value pr0 (converged induction command value) of the compared power control device. This is because the compared power control device uses the control information (difference value ΔP) as it is when calculating the induction command value, whereas the power control device B1 uses a pre-adjustment control value obtained by subtracting an adjustment width from the control information (difference value ΔP) when calculating the induction command value. Therefore, as shown in FIG. 3(a), the induction command value pr1 calculated by the power control device B1 is different from the induction command value pr0 calculated by the compared power control device.

[0045] Due to such a difference in the induced command values, as shown in FIG. 3(b), the difference value ΔP of the compared power control device converges to 0 kW, whereas the difference value ΔP of the power control device B1 converges to approximately -40 kW. In the compared power control device, the difference (difference value ΔP) between the value of the connection point power and the overall target is used directly to calculate the induced command value, so the calculated induced command value becomes a value for making the connection point power (i.e., the sum of the system power and the primary control capacity) the overall target. In other words, power is controlled so that the connection point power (the sum of the system power and the primary control capacity) becomes the overall target, so the difference value ΔP becomes 0 kW. Therefore, in the compared power control device, power is controlled as the connection point power without distinguishing between the system power and the primary control capacity, so the system power control and the primary control capacity control are not controlled separately. In contrast, in the power control device B1, the difference between the connection point power value and the overall target (difference value ΔP) is subtracted by the adjustment width (power adjusted by primary control capability) before calculating the induced command value, so the calculated induced command value is a value for making the value obtained by subtracting the primary control capability from the connection point power (i.e., system power) the overall target. In other words, power is controlled so that the system power becomes the overall target, so the difference value ΔP converges to a value shifted from 0 kW by the power of the primary control capability. In the simulation result shown in FIG. 3(b), the difference value ΔP is −40 kW, and the power control device B1 supplies 40 kW of power as the primary control capability. Therefore, in the power control device B1, power control is performed by distinguishing between the system power and the primary control capability, and the system power control and the primary control capability control are each controlled separately.

[0046] From the above simulation results, the following can be understood. In a configuration without the control value calculation unit 23, as in the comparative power control device, the induced command value is calculated from the control information (the difference between the connection point power and the overall target) without taking into account the adjustment width, so the calculated induced command value is a value for making the connection point power the overall target. Therefore, since power control is performed so that the connection point power becomes the overall target, when the primary control capacity is provided (when the primary control capacity is superimposed on the system power), the system power cannot be controlled to the overall target. In contrast, in the power system S1, the control value calculation unit 23 is provided in the power control device B1, and the induced command value is calculated by taking into account (subtracting) the adjustment width from the control information. As a result, the calculated induced command value is a value for making the power (i.e., the system power) obtained by subtracting the primary control capacity from the connection point power into the overall target. Therefore, in the power system S1, even when the primary control capacity is provided, power control can be performed so that the system power becomes the overall target.

[0047] The functions and effects of the power system S1 of the present disclosure are as follows.

[0048] In the power system S1, the processing device A1 generates control information and transmits the generated control information to the power control device B1. The power control device B1 receives the control information and calculates an induction command value using the received control information. Then, using the calculated induction command value, it calculates an equipment target and controls the output power. In this configuration, the power control device B1 calculates the induction command value. Therefore, the processing device A1 only generates control information for calculating the induction command value and transmits it to the power control device B1. Therefore, the power system S1 can reduce the calculation load of the processing device A1 more than the power system described in Patent Document 1.

[0049] In particular, in the power system S1, the power control device B1 calculates a pre-adjustment control value that takes into account an adjustment range in the control information, and calculates an induction command value using the pre-adjustment control value. Then, the induction command value is used to calculate an output reference value, and the control range is added to the output reference value to calculate an equipment target. With this configuration, as can be seen from the simulation results in Fig. 3, the power system S1 can control the system power control and the primary control capacity control separately, and therefore can provide primary control capacity appropriately.

[0050] In the above embodiment, the generating unit 13 generates the difference (difference value ΔP) between the connection point power value and the overall target as the control information. Unlike this configuration, the generating unit 13 may generate the connection point power value and the overall target as the control information. That is, the control information may include the connection point power value 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 connection point power value and the overall target from the received control information, and calculate the pre-adjustment control value by subtracting the adjustment width from the calculated difference value ΔP. According to this configuration, the processing device A1 simply transmits the acquired connection point power value and the overall target as control information to the power control device B1 as they are. Therefore, the power system according to this modification can further reduce the calculation load of the processing device A1 compared to the above power system S1.

[0051] 4 shows a power system S2 according to a first modified example of the present disclosure. The power system S2 differs from the power system S1 in the following respect. That is, the power control device B1 includes two filter units 281, 282. Each of the filter units 281, 282 is, for example, a low-pass filter, and removes fluctuation components that are steeper than the frequency fluctuation in the primary control capacity (the above-mentioned fluctuation in the very short period of time).

[0052] Filter unit 281 is connected between adjustment range calculation unit 22 and control value calculation unit 23. Thus, the output signal (adjustment range) of adjustment range calculation unit 22 is input to control value calculation unit 23 via filter unit 281. When high-speed disturbance noise is superimposed in power system D, the value of the output frequency measured by adjustment range calculation unit 22 may fluctuate more abruptly than fluctuations in an extremely short period. Such abrupt fluctuation in the output frequency may also cause abrupt fluctuations in the output signal of adjustment range calculation unit 22. Therefore, filter unit 281 removes the abrupt fluctuations contained in the output signal of adjustment range calculation unit 22.

[0053] The filter unit 282 is connected between the receiver 21 and the control value calculation unit 23. Therefore, the output signal (control information) of the receiver 21 is input to the control value calculation unit 23 via the filter unit 282. When high-speed disturbance noise is superimposed in the power system D, the value of the connection point power measured by the measurement unit 31 may fluctuate more abruptly than fluctuations in an extremely short period. Such abrupt fluctuation of the connection point power may also cause abrupt fluctuations in the output signal of the receiver 21 (control information transmitted from the processing device A1). Therefore, the filter unit 282 removes the abrupt fluctuations contained in the output signal (control information) of the receiver 21.

[0054] In the power system S2, like the power system S1, the calculation load of the processing device A1 can be reduced more than in the power system described in Patent Document 1. In the power system S2, like the power system S1, the system power control and the primary control capability control can be controlled separately, so that the provision of primary control capability can be appropriately performed.

[0055] In the power system S2, the power control device B1 includes two filter units 281, 282. This makes it possible to suppress the influence of superimposition of high-speed disturbance noise (noise that is steeper than an extremely short period) even during times when frequency fluctuations in the power system D are unstable, enabling stable control. In other words, the power system S2 can control the system power control and the primary regulation capability control more stably.

[0056] In the above-mentioned first modified example (power system S2), an example in which the power control device B1 includes two filter units 281, 282 has been shown. However, unlike this example, the power control device B1 may include only one of the two filter units 281, 282. In this case, it is preferable that the power control device B1 includes the filter unit 281 rather than the filter unit 282. An adjustment width is input to the filter unit 281, and control information is input to the filter unit 282. The adjustment width is mainly related to the control amount of the output power by the primary adjustment capability, and the control information is mainly related to the control amount of the system power. In addition, the primary adjustment capability control is required to respond faster than the system power control. Therefore, if a sudden change occurs in the adjustment width, there is a risk that the equipment target will be destabilized more than if a sudden change occurs in the control information. For this reason, when the power control device B1 includes either one of the two filter units 281, 282, filter unit 281 is more preferable than filter unit 282 in terms of stabilizing the equipment target, i.e., stabilizing the output power of the power system S2.

[0057] 5 shows a power system S3 according to a second modification of the present disclosure. The power system S3 differs from the power system S1 in the following respect: the processing device A1 of the power system S1 uses a measured value (a value measured by the measuring unit 31) as the value of the connection point power, whereas the processing device A1 of the power system S3 uses an estimated value as the value of the connection point power.

[0058] As shown in Fig. 5, the power control device B1 of the power system S3 includes a transmission unit 29. The transmission unit 29 receives an input of the value of the output power (control power) of the power device X connected to the power control unit 27 from the power control unit 27. Since the power control unit 27 detects the value of the output power in controlling the output power, it is sufficient to output this value to the transmission unit 29. The transmission unit 29 transmits the input value of the output power to the processing device A1. In other words, the value of the output power of the power device X is transmitted to the processing device A1.

[0059] The power system S3 also includes a load monitor 40. The load monitor 40 monitors the power consumption of the power load L. The load monitor 40 transmits the value of the power consumption of the power load L to the processing device A1.

[0060] In the power system S3 configured in this manner, the processing device A1 receives the value of the output power from the power control device 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 a value of the connection point power calculated from the received value of the output power and the value of the power consumption of the power load L (for example, the sum of these) as an estimated value of the connection point power. In this way, the processing device A1 may create control information from the estimated value of the connection point power.

[0061] In the power system S3, like the power system S1, the calculation load of the processing device A1 can be reduced more than in the power system described in Patent Document 1. In the power system S3, like the power system S1, the system power control and the primary control capability control can be controlled separately, so that the provision of primary control capability can be appropriately performed.

[0062] As can be seen from the power system S3, in the power system of the present disclosure, the value of the connection point power can be not only a measured value but also an estimated value. In the power system of the present disclosure, the processing device A1 may switch between using the measured value of the connection point power or the estimated value of the connection point power according to the control mode to be set.

[0063] 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]

[0064] S1, S2, S3: power system, A1: processing device, 11: first acquisition unit, 12: second acquisition unit, 13: generation unit, 15: transmission unit, B1: power control device, 21: 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: storage battery, L: power load (load), D: power system, K: connection point

Claims

1. A power system connected to a power grid and supplying a primary control reserve to the power grid, a power control device that is connected to the power system via a connection point and controls the output of a connected power device; A processing device capable of communicating with the power control device; Equipped with a connection point power that is power at the connection point includes the primary control capacity and a system power that is output power of the power system when the primary control capacity is not provided, The processing device includes: A first acquisition unit that acquires a value of the connection point power; A second acquisition unit that acquires an overall target that is a target value of the system power; a generation unit that generates control information using the connection point power value and the overall target; a transmitter that transmits the control information to the power control device; The power control device includes: an adjustment range calculation unit that calculates an adjustment range, which is a power value to be adjusted for providing the primary control reserve; A receiving unit for receiving the control information; a control value calculation unit that calculates a pre-adjustment control value by adding the adjustment width to the control information; a command value calculation unit that calculates a guidance command value using the pre-adjustment control value; a reference value calculation unit that calculates an output reference value for making the system power the overall target by using the induction command value; a target calculation unit that calculates an equipment target, which is a target value of the output power of the power control device, by taking into account the adjustment width to the output reference value; a power control unit that controls the power equipment so that the output power of the power control device becomes the equipment target.

2. The generation unit generates a difference between the connection point power and the overall target as the control information; the control value calculation unit calculates the pre-adjustment control value by subtracting the adjustment width from the control information; The power system according to claim 1 , wherein the target calculation unit calculates the appliance target by adding the adjustment width to the output reference value.

3. The power control device includes a filter unit that removes fluctuation components that are steeper than frequency fluctuations in the primary control capability, The power system according to claim 1 , wherein the adjustment range calculation unit outputs the adjustment range to the control value calculation unit via the filter unit.

4. The power system according to claim 1 , wherein the adjustment range calculation unit measures a frequency of the output voltage of the power control unit as an output frequency, and calculates the adjustment range using a frequency deviation of the output frequency from a reference frequency.

5. The power system according to claim 1 , wherein the power control device is connected to a storage battery as the power device, and controls charging and discharging of the storage battery.

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