Charging and discharging control method of charging and discharging element and charging and discharging control device of charging and discharging element

Abstract

A charging and discharging control method for a charging and discharging element receives a request value (Pfr) of a frequency adjustment capacity corresponding to a system frequency (f) of an electric power system (10) broadcasted to a plurality of charging and discharging elements (EV1, EV2, EV3, ...) connected to an electric wire (12) of an electric power system (10), determines an output characteristic of charging and discharging relative to the system frequency (f) based on a priority (β) indicating the degree to which charging or discharging of the own (EV1) is prioritized over charging or discharging of other charging and discharging elements (EV2, EV3, ...) and the received request value (Pfr), corrects the output characteristic in such a way that an upper limit or a lower limit of an output range is increased as the priority (β) increases, and charges or discharges at an output determined based on a deviation (Δf) between a system frequency (f) and a reference frequency (fref) measured at a connection end relative to the electric power system (10) and the corrected output characteristic.

Description

Technical Field

[0001] The present invention relates to a charge and discharge control method of a charge and discharge element and a charge and discharge control device of the charge and discharge element. Background Art

[0002] Patent document 1 describes the technology of the frequency stabilization system of the power system. In this technology, the system frequency is measured on the power system side, and the frequency adjustment capacity of the power system is calculated based on the deviation between the measured system frequency and the reference frequency. In addition, information corresponding to the calculated frequency adjustment capacity is simultaneously sent from the power system side to multiple power receiving control loads connected to the power system. Each power receiving control load measures the system frequency by itself, and controls the power receiving of each power receiving control load based on the measured system frequency, the information received from the power system side, and the reference frequency.

[0003] Patent Document 1: Japanese Patent No. 5598896 Summary of the invention

[0004] Patent Document 1 cites an electric vehicle as an example of an optimal power-receiving controlled load. Regarding electric vehicles, the charge and discharge output characteristics of the battery are sometimes set according to their own priority. Their own priority indicates the degree to which the charge and discharge of their own battery takes precedence over the charge and discharge of the batteries of other electric vehicles connected to the same power system.

[0005] If an electric vehicle sets the charge and discharge output characteristics of the battery according to its own priority, a charge and discharge output characteristic with a smaller output range is set for an electric vehicle with a lower priority than for an electric vehicle with a higher priority. For an electric vehicle with a smaller output range of the charge and discharge output characteristics, the frequency adjustment capacity obtained by power control is reduced compared to an electric vehicle with a larger output range of the charge and discharge output characteristics. Therefore, with respect to the technology of Patent Document 1, for example, when the battery of an electric vehicle is set as a power control load and power control is performed, sometimes the frequency adjustment capacity calculated by the system side cannot be fully ensured due to the influence of the priority set for the electric vehicle.

[0006] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to ensure, on the charging and discharging element side, a sufficient frequency regulation capacity calculated on the power system side.

[0007] In order to solve the above-mentioned problem, in a charging and discharging control method of a charging and discharging element involved in one embodiment of the present invention, a plurality of charging and discharging elements connected to the electric wires of the power system receive a request value of a frequency adjustment capacity corresponding to the system frequency of the power system broadcasted to all charging and discharging elements. The output characteristics of charging and discharging relative to the system frequency determined based on the priority indicating the degree to which the charging or discharging of the charging and discharging elements is prioritized over other charging and discharging elements and the received request value are corrected in such a way that the upper limit or lower limit of the output range is increased as the priority is higher, and charging or discharging is performed based on the deviation of the system frequency measured at the connection end relative to the power system from the reference frequency of the power system and the corrected output characteristics.

[0008] Effects of the Invention

[0009] According to the present invention, it is possible to sufficiently ensure the frequency regulation capacity calculated on the power system side on the charging and discharging element side. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a diagram showing the configuration of an electric power system including charging and discharging elements to which a charging and discharging control method according to an embodiment of the present invention is applied.

[0011] Figure 2 Yes means Figure 1 A block diagram of the structure of a charge and discharge control device of an electric vehicle and its peripheral devices.

[0012] Figure 3 It means Figure 2 A graph showing the relationship between the charge and discharge output characteristics and the charge and discharge reference characteristics according to the priority of the electric vehicle determined by the characteristic determination unit.

[0013] Figure 4 It means in Figure 1 Electric vehicles Figure 2 A graph showing the relationship between an actual value of the frequency regulation capacity obtained in the power system and a requested value of the frequency regulation capacity broadcasted by the broadcasting unit to each electric vehicle when charging and discharging are performed according to the output characteristics determined by the characteristic determination unit.

[0014] Figure 5 It means Figure 2 A graph showing the relationship between the charge and discharge output characteristics according to the priority of the electric vehicle determined by the characteristic determination unit and the charge and discharge output characteristics corrected by the characteristic correction unit.

[0015] Fig. 6A yes Figure 1 A flowchart in which processing steps executed by an information sending device are arranged in chronological order.

[0016] Figure 6B yes Figure 1 A flowchart showing the processing steps executed by the charge and discharge control device arranged in time series.

[0017] Fig. 7A Yes means Figure 2 A graph of the output characteristics of the charging corrected by the characteristics correction unit.

[0018] Figure 7B Yes means Figure 2 A graph showing output characteristics of charging for each priority level determined by a characteristic determination unit.

[0019] Figure 8 It schematically shows that other charge and discharge output characteristics across the charge side and the discharge side compensate for Figure 2 A graph showing the output characteristics of only a portion of the output characteristics on the charging side corresponding to the system frequency having a value less than or equal to the basic power, determined by the characteristics determination unit. DETAILED DESCRIPTION

[0020] The embodiment and its modified examples, and specific examples to which the embodiment and its modified examples are applied will be described with reference to the drawings. In the description of the drawings, the same reference numerals are given to the same parts, and the description thereof will be omitted.

[0021] (Power System)

[0022] Reference Figure 1 The configurations of an electric vehicle each equipped with a charge and discharge control device according to the embodiment and a power system connected to the electric vehicle will be described.

[0023] The electric vehicles EV1 to EV3 (an example of a charging and discharging element) are respectively equipped with a charging and discharging control device according to the embodiment, and are electrically connected to the power grid 11 via a common electric wire 12. Other power consuming elements are also connected to the electric wire 12. The other power consuming elements and the electric vehicles EV1 to EV3 constitute a load group to which power is supplied from the power grid 10.

[0024] The electric vehicles EV1 to EV3 can receive power (charge) from the power grid 11 via the power line 12, and can transmit power (discharge) to the power grid 11. Each charge and discharge control device independently controls the power (charge and discharge power) charged and discharged by the electric vehicles EV1 to EV3 equipped with the electric vehicles EV1 to EV3. The number of electric vehicles (EVs) connected to the power line 12 and autonomously controlling the charge and discharge power is not limited to Figure 1 3 units shown.

[0025] The electric wire 12 is connected to the power grid 11 via the current measuring device 15 and the transformer 14. The electric vehicles EV1 to EV3 receive power from the current measuring device 15 and transmit power to the current measuring device 15. As an example of the transformer 14, a pole transformer (pole transformer) that changes the voltage applied to the high-voltage distribution line to a voltage used in homes, offices, etc. can be cited.

[0026] The current measuring device 15 measures the current flowing through the electric wire 12, and calculates the present value (Pall_now) of the total charge and discharge power of all electric vehicles EV1 to EV3 charged or discharged through the electric wire 12 based on the measured current and the voltage of the electric wire 12. In addition, the current measuring device 15 measures the system frequency (f) of the power system 10 based on the measured current. The system frequency (f) is the frequency of the current flowing through the electric wire 12.

[0027] When the demand and supply of electricity are balanced in the power system 10, the system frequency (f) becomes the reference frequency (fref). If the demand and supply balance of electricity in the power system 10 is disrupted, the system frequency (f) changes relative to the reference frequency (fref). For example, if the demand for electricity in the power system 10 is lower than the supply, the system frequency (f) is higher than the reference frequency (fref). If the demand for electricity in the power system 10 exceeds the supply, the system frequency (f) is lower than the reference frequency (fref).

[0028] The power system 10 is a power system that controls the flow of power from both the supply side and the demand side and can achieve optimization. The power system 10 is a concept that includes smart grids, smart communities, and microgrids or MEMS (Mansion Energy Management System) that manage the terminal consumption part from the energy supply source using the communication network within a limited range of offices, factories, etc. Figure 1 The electric network 11, electric wires 12, transformers 14, and current measuring devices 15 are shown. The electric network 11 includes various power plants such as thermal power, nuclear power, and hydropower, and substations that transform voltage from hundreds of thousands of volts (V) to thousands of volts.

[0029] In the embodiment, the power system 10 further includes an information transmission device 16. The information transmission device 16 is a computer or server that controls and optimizes the flow of power from both the supply side and the demand side, and is connected to the current measurement device 15 via a computer network. Alternatively, various power information may be obtained from the current measurement device 15 via the power grid 11.

[0030] The information sending device 16 includes: a calculation unit 17, which generates a signal requesting charging or discharging to all electric vehicles EV1~EV3 based on various power information supplied from the power system 10; and a broadcast sending unit 18a and a broadcast sending device 18b, which broadcast the signal generated by the calculation unit 17 to the electric vehicles EV1~EV3.

[0031] If the system frequency (f) input from the current measuring device 15 changes relative to the reference frequency (fref), the calculation unit 17 generates a signal requesting charging or discharging to all electric vehicles EV1 to EV3. The generated signal requests all electric vehicles EV1 to EV3 to charge or discharge in order to restore the system frequency (f) to the reference frequency (fref).

[0032] The signal generated by the calculation unit 17 includes a request for charging or discharging all electric vehicles EV1 to EV3, that is, a “system request.” The system request is, for example, a differential power (ΔP) obtained by subtracting a current value (Pall_now) of the total charge / discharge power from a maximum value (Pall_max) of the total charge / discharge power.

[0033] The maximum value (Pall_max) of the total charge and discharge power is the maximum value of the amount of power that can be charged or discharged by all the electric vehicles EV1 to EV3 via the electric line 12. The current value (Pall_now) of the total charge and discharge power is the current value of the amount of power that can be charged or discharged by all the electric vehicles EV1 to EV3 via the electric line 12. The differential power (ΔP) obtained by subtracting the current value (Pall_now) of the total charge and discharge power from the maximum value (Pall_max) of the total charge and discharge power is the request value (Pfr) of the frequency adjustment capacity for balancing the demand and supply of power in the power system 10 by making the system frequency (f) consistent with the reference frequency (fref).

[0034] The information transmitting device 16 receives the system frequency (f) of the power system 10 measured by the current measuring device 15 via the computer network or the power grid 11. The information transmitting device 16 has a storage device for storing data indicating the basic output characteristics of the total charge and discharge power (Pall) relative to the system frequency (f) of the power system 10, and the calculation unit 17 calculates the maximum value (Pall_max) of the total charge and discharge power using the system frequency (f) received from the current measuring device 15 and the data of the basic output characteristics read from the storage device.

[0035] As shown in formula (1), the calculation unit 17 calculates the differential power (ΔP) by subtracting the current value (Pall_now) of the total charge and discharge power from the maximum value (Pall_max) of the total charge and discharge power. In the case where the power system 10 requests charging of the electric vehicles EV1 to EV3, the calculation unit 17 calculates the differential power for charging. The differential power for charging is calculated by subtracting the current value of the total charge power transmitted to all the electric vehicles EV1 to EV3 via the electric wire 12 from the maximum value of the total charge power that can be transmitted to all the electric vehicles EV1 to EV3 via the electric wire 12.

[0036] On the other hand, when the electric power system 10 requests the electric vehicles EV1 to EV3 to discharge, the calculation unit 17 calculates the differential power (ΔP) of discharge. The differential power of discharge is calculated by subtracting the current value of the total discharge power received from all the electric vehicles EV1 to EV3 via the electric line 12 from the maximum value of the total discharge power received by all the electric vehicles EV1 to EV3 via the electric line 12. The differential power (ΔP) is a positive value greater than or equal to 0, and is a concept that includes the differential power of charge and the differential power of discharge.

[0037] In addition, the state of the electric power system 10 requesting the electric vehicles EV1 to EV3 to charge or discharge varies according to the demand and supply balance of the electric power of the electric power system 10. The information transmitting device 16 has a storage device that pre-stores data indicating the maximum value (Pall_max) of the total charge and discharge power, and the calculation unit 17 calculates the differential power (ΔP) using the data indicating the maximum value (Pall_max) of the total charge and discharge power read from the storage device. As a method for calculating the differential power (ΔP), the method disclosed in International Publication No. 2020 / 194010 can be used.

[0038] [Mathematical formula 1]

[0039] ΔP=P all_max -P all_now …(1)

[0040] The broadcast transmission unit 18a broadcasts (broadcasts) to all electric vehicles EV1 to EV3 using the broadcast transmission device 18b an electrical signal indicating the requested value (Pfr) of the frequency adjustment capacity calculated as the differential power (ΔP) by the calculation unit 17. In addition, after broadcasting the requested value (Pfr), the broadcast transmission unit 18a broadcasts (broadcasts) to all electric vehicles EV1 to EV3 using the broadcast transmission device 18b an electrical signal indicating the surplus or shortage capacity (ΔPfr) of the frequency adjustment capacity.

[0041] The surplus capacity (ΔPfr) of the frequency adjustment capacity is the difference between the theoretical value and the actual value of the charge and discharge output of all electric vehicles EV1 to EV3. Regarding the theoretical value of the charge and discharge output of all electric vehicles EV1 to EV3, the calculation unit 17 can calculate it based on the deviation (Δf) of the system frequency (f) (actual measurement value) of the electric wire 12 connected to all electric vehicles EV1 to EV3 measured by the current measuring device 15 after the broadcast transmission of the request value (Pfr) relative to the reference frequency (fref), and the data of the basic output characteristics read from the storage device of the information transmitting device 16. The actual value of the charge and discharge output of all electric vehicles EV1 to EV3 can be set to the current value (Pall_now) of the total charge and discharge power of all electric vehicles EV1 to EV3 calculated by the current measuring device 15 after the broadcast transmission of the request value (Pfr).

[0042] As a method of broadcast transmission, a wireless LAN (Local Area Network) such as Wi-Fi (Wireless: registered trademark) or Bluetooth (registered trademark) can be used.

[0043] In the embodiment, "electric vehicles EV1~EV3" is an example of a "charging and discharging element" that charges and discharges electricity via the electric wire 12. The charging and discharging element stores the received electricity in a battery (including a secondary battery, a storage battery, and a rechargeable battery). "Charging and discharging elements" include all equipment and devices with batteries, such as vehicles (including electric vehicles, hybrid vehicles, construction machinery, and agricultural machinery), railway vehicles, toys, tools, household products, and daily necessities. In the embodiment, as an example of a charging and discharging element, an electric vehicle (EV) that uses electricity as an energy source and a motor as a power source can be cited. However, it does not mean that the charging and discharging element of the present invention is limited to electric vehicles (EV).

[0044] The "charge and discharge element" represents a unit structure of charge and discharge control by the charge and discharge control device according to the embodiment. That is, the charge and discharge control according to the embodiment is performed on a charge and discharge element basis. For example, charge and discharge control is performed independently and in parallel for a plurality of electric vehicles EV1 to EV3.

[0045] (Electric Vehicles)

[0046] Reference Figure 2 The structures of the charge and discharge control device 23 and its peripheral devices respectively mounted on the electric vehicles EV1 to EV3, ... connected to the electric wire 12 are described. In addition, hereinafter, the electric vehicle EV1 among the electric vehicles EV1 to EV3, ... is described as an example, but the other electric vehicles EV2, EV3, ... also have the same structure and can operate in the same manner.

[0047] The electric vehicle EV1 is equipped with a receiving device 21 (receiving unit), a vehicle state acquisition device 22 , a charging and discharging device 24 , a motor 26 , and a battery 25 as peripheral devices of a charging and discharging control device 23 .

[0048] The receiving device 21 is a device that receives the electric signal (wireless signal) broadcasted from the broadcasting device 18b. The electric signal received by the receiving device 21 includes a signal requesting charging or discharging to all electric vehicles EV1 to EV3. The signal includes a signal indicating a requested value (Pfr) of the frequency adjustment capacity of the power system 10 as an example of a system request, and a signal indicating the surplus or shortage capacity (ΔPfr) of the frequency adjustment capacity.

[0049] The vehicle state acquisition device 22 acquires information indicating the state of the electric vehicle EV1. For example, the "state of the electric vehicle EV1" includes the current value (SOCnow) of the charge rate of the battery 25 of the electric vehicle EV1, and a numerical value indicating the request of the user of the electric vehicle EV1. The numerical value indicating the request of the user of the electric vehicle EV1 is, for example, the target value (SOCgoal) of the charge rate of the battery 25, and the time to end the charge and discharge of the electric vehicle EV1 (the end time Td of the charge and discharge). The remaining time (T) until the end time Td is the remaining time that the electric vehicle EV1 can charge and discharge.

[0050] The charging and discharging device 24 is an on-board charger (OBC), and performs charging and discharging of the battery 25 via the electric wire 12 under the control of the charging and discharging control device 23. The charging and discharging device 24 stores the received power in the battery 25. Alternatively, the charging and discharging device 24 may not store the received power in the battery 25, but directly send power to the motor 26 as a driving source. On the other hand, the charging and discharging device 24 discharges the power stored in the battery 25 or the power generated by the motor 26 to the power grid 11 via the electric wire 12.

[0051] The charging and discharging device 24 has an ammeter 24a. The ammeter 24a measures the current flowing in the electric wire 12 at a position on the electric wire 12 to which the electric vehicle EV1 is connected. The position on the electric wire 12 to which the electric vehicle EV1 is connected is referred to as the "receiving end" of the electric vehicle EV1. The charging and discharging device 24 can measure the system frequency (f) of the power system 10 at the receiving end of the electric vehicle EV1.

[0052] The battery 25 includes a secondary battery, a storage battery, and a rechargeable battery that stores the electric power received by the charging and discharging device 24. The motor 26 is a driving source of the electric vehicle EV1 that is driven based on the electric energy or electric power stored in the battery 25.

[0053] The charge and discharge control device 23 can be implemented by a microcomputer including a CPU (central processing unit), a memory, and an input and output unit. A computer program for causing the microcomputer to function as the charge and discharge control device 23 is installed in the microcomputer and executed. Thus, the microcomputer can function as a plurality of information processing units (31 to 38) possessed by the charge and discharge control device 23. Here, an example of implementing the charge and discharge control device using software is shown, but of course, the charge and discharge control device 23 can also be constituted by preparing dedicated hardware for performing each information processing. The dedicated hardware includes devices such as an integrated circuit (ASIC) for a specific purpose and current-type circuit components configured in a manner to perform the functions described in the embodiment.

[0054] In addition, the charge and discharge control device 23, the receiving device 21, the vehicle state acquisition device 22, and the charge and discharge device 24 are described as different components, but it is of course possible to make arbitrarily selected devices greater than or equal to 2 constitute one device. Alternatively, the multiple information processing units (31 to 38) can be divided and constituted by using greater than or equal to 2 different devices. In addition, all or part of the multiple information processing units (31 to 38) can be constituted by using other ECUs (Electronic Control Units) installed in the electric vehicle EV1.

[0055] The charge and discharge control device 23 can apply the processing performed by the power reception control device disclosed in International Publication No. 2020 / 194010 to the processing related to the charge and discharge control of other electric vehicles EV1 except the processing related to the correction of the priority (β) shown below.

[0056] As multiple information processing units (31~38), the charge and discharge control device 23 has a charge and discharge request acquisition unit 31, a current information acquisition unit 32, a system frequency measurement unit 33, a priority calculation unit 34, a characteristic determination unit 35, a characteristic correction unit 36, a charge and discharge power determination unit 37 and a charge and discharge control unit 38.

[0057] The charge / discharge request acquisition unit 31 acquires information indicating a requested value (Pfr) of the frequency regulation capacity of the power system 10 as an example of a system request from the electric signal received by the receiving device 21 , and acquires information indicating the surplus / deficient capacity (ΔPfr) of the frequency regulation capacity.

[0058] The current information acquisition unit 32 acquires the current value of the electric wire 12 measured by the ammeter 24 a of the charging and discharging device 24 at the connection end of the electric vehicle EV1 with respect to the electric wire 12 .

[0059] The system frequency measuring unit 33 measures the system frequency (f) of the electric wire 12 using the current value of the electric wire 12 acquired by the current information acquiring unit 32 .

[0060] The priority calculation unit 34 calculates the priority (β) of the electric vehicle EV1, which indicates the degree to which the charging and discharging of EV1 itself is prioritized over the charging and discharging of other electric vehicles (EV2, EV3, ...), based on the numerical value indicating the request of the user of the electric vehicle EV1 (the state of the electric vehicle EV1). The priority (β) can be set separately for the charging side and the discharging side.

[0061] The priority calculation unit 34 calculates the priority (β) of the electric vehicle EV1, which indicates the degree to which the charging or discharging of EV1 itself is prioritized compared with the charging or discharging of other electric vehicles (EV2, EV3, ...), based on the numerical value representing the request of the user of the electric vehicle EV1 and the state of the electric vehicle EV1. Specifically, the priority calculation unit 34 uses formula (2) and calculates the priority (β) according to the remaining time (T) from the current time (To) to the end time (Td) of charging and discharging. In formula (2), N represents the total number of electric vehicles being charged and discharged. As a method for calculating the priority (β) using the current value (SOCnow) of the charging rate and the target value (SOCgoal) of the charging rate, the method disclosed in International Publication No. 2020 / 194010 can be used.

[0062] [Mathematical formula 2]

[0063]

[0064] The characteristic determination unit 35 determines the output characteristic of the charge and discharge of the electric vehicle EV1 relative to the system frequency (f) based on the priority (β) calculated by the priority calculation unit 34 and the frequency adjustment capacity (Pfr) received by the receiving device 21. The output characteristic defines the charge and discharge output of the electric vehicle EV1 at each frequency in the adjustment range of the system frequency (f) centered on the reference frequency (fref). For example, when the reference frequency (fref) is 50Hz, the adjustment range of the system frequency (f) can be set to ±0.2Hz.

[0065] The characteristic determination unit 35 divides the total number of electric vehicles (N) by the frequency adjustment capacity (Pfr) to set the output range of the adjustment range of the system frequency (f) of the reference characteristic of the charge and discharge of the electric vehicle EV1. The output range of the charge and discharge of the electric vehicle EV1 of the adjustment range of the system frequency (f) is the element frequency adjustment capacity (Pfr / N) obtained by the charge and discharge of the electric vehicle EV1 in the power line 12. For example, Figure 3As shown by the solid line of , the charge and discharge reference characteristic is a linear characteristic in which the output of the reference frequency (fref) is set to zero. Regarding the reference characteristic, the output upper limit value of the charging side is defined at the highest frequency in the adjustment range of the system frequency (f), and the output upper limit value of the discharging side is defined at the lowest frequency in the adjustment range.

[0066] The total number of electric vehicles (N) may be statistical data (quantity data) obtained by searching the past charge and discharge history of the load group of the power system 10 including the electric vehicles connected to the electric line 12, or the total number of electric vehicles (N) may be estimated based on the current value (Pall_now) of the total charge and discharge power. The total number (N) is broadcasted from the information transmitting device 16 or a device attached to the information transmitting device 16 in the same manner as the differential power (ΔP). Alternatively, the total number (N) may be determined using the location information of the charging system of the electric vehicle, an identification signal, etc.

[0067] The characteristic determination unit 35 corrects the reference characteristic of charging and discharging according to the priority (β) of the electric vehicle EV1, and determines the output characteristic of charging and discharging of the electric vehicle EV1. For example, when the priority calculation unit 34 calculates the priority of the charging side and the priority of the discharging side, the characteristic determination unit 35 corrects the output upper limit value of the charging side according to the priority of the charging side, and corrects the output upper limit value of the discharging side according to the priority of the discharging side.

[0068] exist Figure 3 In the figure, the dotted lines respectively show the output characteristics corrected for the reference characteristics according to the priority (β) of the electric vehicle EV1. The dotted line with the shortest peak value represents the corrected output characteristics when the priority on the charging side is 0.5 and the priority on the discharging side is 1. The dotted line with the longest peak value represents the corrected output characteristics when the priority on the charging side is 1 and the priority on the discharging side is 0.5. The dotted line with a peak value of intermediate length represents the corrected output characteristics when both the priority on the charging side and the priority on the discharging side are 0.5.

[0069] If the reference characteristic is corrected according to the priority (β), the output range of the electric vehicle EV1 for charging and discharging of the system frequency (f) is smaller than before the correction. That is, by correcting the reference characteristic according to the priority (β) of the electric vehicle EV1, the frequency adjustment capacity of the element obtained by charging and discharging the electric vehicle EV1 in the electric wire 12 is reduced compared with before the correction.

[0070] exist Figure 4In FIG. 1 , the dotted ideal output contour line represents the frequency adjustment capacity obtained by summing up the element frequency adjustment capacities obtained in each electric vehicle EV1 to EV3, ..., which is charged and discharged with the reference characteristic. In addition, the solid actual output contour line represents the total value of the element frequency adjustment capacity when each electric vehicle EV1 to EV3, ... is charged and discharged with the output characteristics corresponding to the respective priorities (β).

[0071] The maximum value of the ideal output profile is the total value of the output range of charge and discharge of each electric vehicle EV1 to EV3, ... of the reference characteristic. This total value is the requested value (Pfr) of the frequency adjustment capacity.

[0072] The maximum value of the actual output profile is the total value of the output range of charging and discharging of each electric vehicle EV1 to EV3, ... of the output characteristic determined by the characteristic determination unit 35. Since the output range of the output characteristic determined by the characteristic determination unit 35 is smaller than the output range of the reference characteristic, the frequency adjustment capacity such as the requested value (Pfr) cannot be obtained in the actual output profile.

[0073] The characteristic correction unit 36 ​​corrects the output characteristics of the charging and discharging of the electric vehicle EV1 determined by the characteristic determination unit 35 based on the received surplus capacity (ΔPfr) of the frequency adjustment capacity when the receiving device 21 receives the surplus capacity (ΔPfr) of the frequency adjustment capacity, for example, when the priority (β) calculated by the priority calculation unit 34 is high, such as a height greater than or equal to a constant value.

[0074] like Figure 5 As shown, the characteristic correction unit 36 ​​corrects the output characteristic of charging and discharging of the electric vehicle EV1, for example, in the following manner, that is, when the surplus capacity (ΔPfr) is large on the charging side, the output upper limit value on the charging side is increased, and when the surplus capacity (ΔPfr) is large on the discharging side, the output upper limit value on the discharging side is increased. Regarding the output characteristic after correction, compared with the output characteristic before correction, the output upper limit value on the charging side or the output upper limit value on the discharging side is close to the output upper limit value of each reference characteristic. Therefore, the output range is expanded compared with before correction and is close to the output range of the reference characteristic.

[0075] The charge / discharge power determination unit 37 calculates the deviation (Δf) of the system frequency (f) of the electric wire 12 measured by the system frequency determination unit 33 from the reference frequency (fref) using the current value of the electric wire 12 measured by the ammeter 24a. The charge / discharge power determination unit 37 determines the element charge / discharge output of the electric vehicle EV1 based on the deviation (Δf) and the output characteristics of charge / discharge determined by the characteristics determination unit 35.

[0076] The charge and discharge control unit 38 controls the charge and discharge device 24 to charge or discharge the electric vehicle EV1 with the element charge and discharge output determined by the charge and discharge power determination unit 37. In this way, the charge and discharge control device 23 repeatedly executes the processing cycle (a) to (h) shown below, thereby controlling the charge and discharge power (P) of the electric vehicle EV1.

[0077] (a) acquiring information indicating differential power (ΔP=request value Pfr of frequency adjustment capacity),

[0078] (b) Calculate the priority (β),

[0079] (c) determining the charge and discharge output characteristics according to the priority (β) based on the requested value (Pfr) of the frequency adjustment capacity,

[0080] (d) determining the element charge and discharge output based on the charge and discharge output characteristics corresponding to the priority (β) according to the deviation (Δf) between the system frequency (f) and the reference frequency (fref) measured at the connection end,

[0081] (e) controlling the charge and discharge device 24 to perform charge and discharge at the determined element charge and discharge output,

[0082] (f) receiving information indicating the difference between the theoretical value and the actual value of the total charge and discharge output, i.e., the remaining capacity (ΔPfr),

[0083] (g) correcting the charge / discharge output characteristics corresponding to the priority (β) based on the received remaining capacity (ΔPfr), and,

[0084] (h) The charge and discharge device 24 is controlled so as to perform charge and discharge at the element charge and discharge output determined based on the corrected charge and discharge output characteristics.

[0085] Reference Fig. 6A Flow chart of Figure 1 An example of the main processing actions performed by the information sending device 16 is described below.

[0086] First, in step S101, the information transmitting device 16 determines the frequency adjustment capacity (Pfr) requested for all the electric vehicles EV1 to EV3, . . . and broadcasts it to all the electric vehicles EV1 to EV3, . . .

[0087] Entering step S102, after the request value (Pfr) is broadcast, the current measuring device 15 measures the system frequency (f) of the electric wires 12 connected to all electric vehicles EV1~EV3,..., and the calculation unit 17 calculates the deviation (Δf) of the system frequency (f) measured by the current measuring device 15 relative to the reference frequency (fref).

[0088] Entering step S103, the calculation unit 17 calculates the theoretical value of the charging and discharging output assumed for all electric vehicles EV1~EV3,... after the request value (Pfr) is broadcast based on the deviation (Δf) calculated by the current measuring device 15 and the data of the basic output characteristics read from the storage device of the information sending device 16.

[0089] Entering step S104, the current measuring device 15 calculates the current value (Pall_now) of the total charge and discharge power of all electric vehicles EV1 to EV3, ... after the broadcast of the request value (Pfr) as an actual value based on the charge and discharge output of all electric vehicles EV1 to EV3, .... Furthermore, the information transmitting device 16 broadcasts the difference between the theoretical value of the charge and discharge output calculated by the calculation unit 17 in step S103 as the surplus capacity (ΔPfr) of the frequency adjustment capacity to all electric vehicles EV1 to EV3, ....

[0090] Reference Figure 6B Flow chart of Figure 2 The following describes an example of a charge and discharge control method of the charge and discharge control device 23. The charge and discharge control method is executed by the charge and discharge control device 23 of each electric vehicle EV1 to EV3, ..., respectively. In addition, those skilled in the art can Figure 2 The specific sequence of the charge and discharge control method of the charge and discharge control device 23 can be easily understood by describing the specific structure and function of the charge and discharge control device 23. Figure 2 The charge and discharge control method of the charge and discharge control device 23 is described, and the main processing actions of the charge and discharge control device 23 are described, and the detailed processing actions are described and referenced. Figure 2 The description is repeated and therefore omitted.

[0091] First, in step S201 , the priority calculation unit 34 calculates the priority (β) of charging and discharging based on the current value (SOCnow) of the charging rate of the battery 25 acquired by the vehicle state acquisition device 22 , the scheduled departure time, and the like.

[0092] Entering step S202, the characteristic determination unit 35 determines the output characteristic of the charge and discharge of the electric vehicle EV1 relative to the system frequency (f) based on the priority (β) calculated by the priority calculation unit 34 in step S201 and the frequency adjustment capacity (Pfr) received by the receiving device 21. The frequency adjustment capacity (Pfr) received by the receiving device 21 is Fig. 6A In step S101, the information sending device 16 broadcasts and sends.

[0093] Proceeding to step S203 , the charge / discharge power determination unit 37 calculates a deviation (Δf) of the system frequency (f) of the power line 12 measured by the system frequency measurement unit 33 from the reference frequency (fref) using the current value of the power line 12 measured by the ammeter 24 a .

[0094] Proceeding to step S204 , the charge / discharge power determination unit 37 determines the element charge / discharge output of the electric vehicle EV1 based on the deviation (Δf) calculated in step S203 and the charge / discharge output characteristics determined in step S202 .

[0095] Entering step S205, the characteristic correction unit 36 ​​corrects the output characteristic of the charge and discharge of the electric vehicle EV1 determined by the characteristic determination unit 35 in step S202 so that the surplus capacity (ΔPfr) is reduced according to the surplus capacity (ΔPfr) of the frequency adjustment capacity received by the receiving device 21. The surplus capacity (ΔPfr) of the frequency adjustment capacity received by the receiving device 21 is Fig. 6A In step S104, the information is broadcasted by the information sending device 16.

[0096] According to the embodiment of the present invention, the following effects can be obtained.

[0097] If the information transmission device 16 of the power system 10 broadcasts the requested value (Pfr) of the frequency adjustment capacity corresponding to the deviation (Δf) of the system frequency (f) relative to the reference frequency (fref), the charge and discharge output characteristics are respectively determined in each electric vehicle EV1~EV3, ... in accordance with the requested value (Pfr). Each electric vehicle EV1~EV3, ... corrects the determined charge and discharge output characteristics according to each priority (β). If the output range of the corrected charge and discharge output characteristics is smaller than that before correction, the frequency adjustment capacity after adding up the charge and discharge outputs of each electric vehicle EV1~EV3, ... does not reach the requested value (Pfr) of the frequency adjustment capacity.

[0098] The information transmitting device 16 has only a one-way communication function for each electric vehicle EV1 to EV3, ..., and therefore the electric power system 10 cannot know the corrected charge and discharge output characteristics of each electric vehicle EV1 to EV3, ... corrected with the priority (β).

[0099] In the present embodiment, in the charge and discharge output of each electric vehicle EV1 to EV3, ..., on the power system 10 side, the calculation unit 17 calculates the assumed theoretical value and the current measuring device 15 calculates the actual value regarding the assumed charge and discharge output for all electric vehicles EV1 to EV3, .... Furthermore, the information transmitting device 16 broadcasts the difference between the actual value and the theoretical value as the surplus capacity (ΔPfr) of the frequency adjustment capacity to all electric vehicles EV1 to EV3, ...

[0100] Regarding each electric vehicle EV1 to EV3, ..., the charge and discharge control device 23 receives the surplus capacity (ΔPfr) of the frequency adjustment capacity transmitted by broadcast, and corrects the output characteristic of the charge and discharge of the electric vehicle EV1 determined by the characteristic determination unit 35 in such a way that the surplus capacity (ΔPfr) is reduced. Figure 5 In the example shown, the charge and discharge output characteristics are corrected so that the surplus capacity (ΔPfr) is reduced on the side where the surplus capacity (ΔPfr) is larger between the charge side and the discharge side.

[0101] If the surplus capacity (ΔPfr) decreases and approaches 0, the actual value of the charge and discharge output of all electric vehicles EV1~EV3, ... approaches the theoretical value, and the system frequency (f) approaches the reference frequency (fref). Therefore, according to the magnitude relationship between the actual value represented by the sign of the surplus capacity (ΔPfr) and the theoretical value, the output characteristics of the charge and discharge output are corrected to increase or decrease the actual value, thereby making it possible to make the frequency adjustment capacity after the charge and discharge output of each electric vehicle EV1~EV3, ... total close to the requested value (Pfr) of the frequency adjustment capacity. As a result, the frequency adjustment capacity calculated on the power system 10 side can be fully ensured by the control performed on the side of each electric vehicle EV1~EV3, ...

[0102] (First Modification)

[0103] In the above embodiment, when the receiving device 21 receives the surplus capacity (ΔPfr) of the frequency adjustment capacity, the characteristic correction unit 36 ​​corrects the output characteristic of the charge and discharge of the electric vehicle EV1 determined by the characteristic determination unit 35 according to the received surplus capacity (ΔPfr) of the frequency adjustment capacity. Alternatively, the characteristic correction unit 36 ​​may calculate the time change rate ((ΔPfrt+1-ΔPfrt) / Δt) per unit time (Δt) of the surplus capacity (ΔPfr) received by the receiving device 21. In this case, the characteristic correction unit 36 ​​can correct the output characteristic of the charge and discharge of the electric vehicle EV1 determined by the characteristic determination unit 35 according to the time change rate ((ΔPfrt+1-ΔPfrt) / Δt).

[0104] If the surplus capacity (ΔPfr) increases with the passage of time, the time change rate of the surplus capacity (ΔPfr) ((ΔPfrt+1-ΔPfrt) / Δt) becomes a positive (+) value, and if the surplus capacity (ΔPfr) decreases, it becomes a negative (-) value.

[0105] When the sign of the time change rate ((ΔPfrt+1-ΔPfrt) / Δt) is positive, the increase of the time change rate ((ΔPfrt+1-ΔPfrt) / Δt) with the passage of time is converted into a decrease, thereby reducing the value of the frequency adjustment capacity (Pfr) that is too large under the current conditions. When the sign of the time change rate ((ΔPfrt+1-ΔPfrt) / Δt) is negative, in order to accelerate the decrease of the time change rate ((ΔPfrt+1-ΔPfrt) / Δt) with the passage of time, the value of the frequency adjustment capacity (Pfr) is increased compared to the current value. In this way, the tracking performance of the actual value relative to the requested value (Pfr) of the frequency adjustment capacity can be improved.

[0106] (Second Modification)

[0107] In addition, the characteristic correction unit 36 ​​can calculate the rate of change of the surplus capacity (ΔPfr) received by the receiving device 21 due to the deviation (Δf) between the system frequency (f) and the reference frequency (fref) as the frequency deviation change rate ((ΔPfrf+1-ΔPfrf) / Δf). In this case, the characteristic correction unit 36 ​​can correct the output characteristic of the charge and discharge of the electric vehicle EV1 determined by the characteristic determination unit 35 based on the frequency deviation change rate ((ΔPfrf+1-ΔPfrf) / Δf).

[0108] If the surplus capacity (ΔPfr) increases due to an increase in the deviation (Δf) between the system frequency (f) and the reference frequency (fref), the frequency deviation change rate ((ΔPfrf+1-ΔPfrf) / Δf) becomes a positive (+) value indicating that the system frequency is higher than the reference frequency. If the surplus capacity (ΔPfr) decreases due to an increase in the deviation (Δf) between the system frequency (f) and the reference frequency (fref), the frequency deviation change rate ((ΔPfrf+1-ΔPfrf) / Δf) becomes a negative (-) value indicating that the system frequency is lower than the reference frequency.

[0109] When the sign of the frequency deviation change rate ((ΔPfrf+1-ΔPfrf) / Δf) is positive, in order to make the system frequency (f) close to the reference frequency (fref) lower than it, the value of the frequency adjustment capacity (Pfr) that is too large under the current situation is reduced. When the sign of the frequency deviation change rate ((ΔPfrf+1-ΔPfrf) / Δf) is negative, in order to make the system frequency (f) close to the reference frequency (fref) higher than it, the value of the frequency adjustment capacity (Pfr) that is too small under the current situation is increased. In this way, the rapidity of restoring the fluctuating system frequency (f) to the reference frequency (fref) can be improved.

[0110] (Third Modification)

[0111] In the above embodiment and the first and second variants, the information transmitting device 16 broadcasts the requested value (Pfr) of the frequency adjustment capacity to all electric vehicles EV1 to EV3 as the total charge and discharge power for all electric vehicles EV1 to EV3. However, the information transmitting device 16 may also broadcast the requested value (Pfr) of the frequency adjustment capacity to all electric vehicles EV1 to EV3 by dividing it into the total charge power and the total discharge power for all electric vehicles EV1 to EV3. In this case, the receiving device 21 of the charge and discharge control device 23 receives the requested value of the frequency adjustment capacity on the charging side and the requested value of the frequency adjustment capacity on the discharge side, respectively.

[0112] If the request value (Pfr) of the frequency adjustment capacity is divided into the request value on the charging side and the request value on the discharging side and distributed, the charge and discharge control device 23 can determine the output characteristics on the charging side and the output characteristics on the discharging side of each electric vehicle EV1 to EV3, ..., respectively. Therefore, the output characteristics can be corrected separately on the charging side and the discharging side according to the priority (β), and the correction process of the output characteristics can be easily performed.

[0113] (Fourth Modification)

[0114] In the above embodiment and the first to third variations, Figure 5 As shown, the upper limit value of the output range of the output characteristics of the charging side and the discharging side is corrected in a manner of increasing to a higher value according to the priority (β) of each electric vehicle EV1, EV2, EV3, ... However, when correcting according to the priority (β), the upper limit value of the output range of the output characteristics of the charging side and the discharging side may not be increased, but the lower limit value may be increased instead.

[0115] For example, in Fig. 7A In the case of the output characteristic of the charging side shown in FIG. 1 , the amount of decrease of the lower limit value of the output range existing only on the charging side relative to the upper limit value is reduced as the priority (β) is higher, and the amount of decrease is increased as the priority (β) is lower. In addition, when the characteristic correction unit 36 ​​corrects the output characteristic of the charge and discharge of the electric vehicle EV1 determined by the characteristic determination unit 35 based on the surplus capacity (ΔPfr) of the frequency adjustment capacity received by the receiving device 21, the amount of decrease of the lower limit value of the output range on the charging side relative to the upper limit value is increased as the surplus capacity (ΔPfr) is larger, and the amount of decrease is decreased as the surplus capacity (ΔPfr) is smaller.

[0116] Even in this case, the electric vehicles EV1, EV2, EV3, ... having higher priorities (β) can be charged with higher electric power regardless of the level of the system frequency (f).

[0117] (Fifth Modification)

[0118] In the fourth variant, the lower the priority (β) of the electric vehicles EV1, EV2, EV3, ..., the greater the trend of the output characteristics on the charging side. In addition, the lower the priority (β) of the electric vehicles EV1, EV2, EV3, ..., the lower the upper limit value of the output range on the charging side. Therefore, the lower the priority (β), the more likely the lower limit value of the output characteristics on the charging side will become a value lower than the base power (Pbase) that the battery 25 always supplies to the dark current load.

[0119] In the case where the electric vehicles EV1 to EV3, ... are charging control elements whose output range of output characteristics exists only on the charging side, if the lower limit value of the charging output is set to a value lower than the basic power (Pbase) always supplied from the battery 25 to the dark current load, the charging output is interrupted at the basic power Pbase on the lowest frequency side of the adjustment range of the system frequency (f). In this state, the battery 25 cannot be charged to obtain the element frequency adjustment capacity (Pfr / N).

[0120] Therefore, when the lower limit value of the output characteristic of the charging side with a lower priority (β) is set to a value lower than the base power (Pbase), as shown in FIG. Figure 7B As shown, the characteristic determination unit 35 may determine the output characteristic with the lower limit set to a value greater than or equal to the base power (Pbase). In this case, the characteristic determination unit 35 may determine the output characteristic of the charging side with a higher priority (β) or a medium priority by setting the lower limit of the output characteristic of the charging side with a lower priority (β) to a value greater than or equal to the base power (Pbase) to compensate for the insufficient element frequency adjustment capacity (Pfr / N) of the charging side.

[0121] Figure 8 It is a curve diagram schematically showing a state in which the output characteristics of the portion of the electric vehicles EV1, EV2, EV3, ... with a lower priority (β) and the output characteristics set only on the charging side determined by the characteristic determination unit 35, corresponding to the system frequency (f) that is less than or equal to the value of the basic power (Pbase), are compensated by the charge and discharge output characteristics of other electric vehicles EV1, EV2, EV3, ... set across the charging side and the discharging side.

[0122] This ensures the continuity of the frequency adjustment capacity for the deviation (Δf) between the system frequency (f) and the reference frequency (fref).

[0123] In addition, the above embodiment is an example of the present invention. Therefore, the present invention is not limited to the above embodiment, and even in a manner other than the embodiment, various changes can be made according to design, etc. as long as they do not deviate from the scope of the technical idea involved in the present invention.

[0124] Description of the label

[0125] 10 Power System

[0126] 12 Wires

[0127] 21Receiving device

[0128] 34 Priority calculation unit

[0129] 35 Characteristic determination unit

[0130] 36Characteristics Correction Department

[0131] 38 Charge and discharge control unit

[0132] EV1, EV2, EV3, ... electric vehicles

Claims

1. A method for controlling charging and discharging of a charging and discharging element, wherein: receiving a request value of a frequency adjustment capacity corresponding to a system frequency of the power system, which is broadcasted to a plurality of charging and discharging elements connected to electric wires of the power system, determining an output characteristic of charging and discharging with respect to the system frequency based on a priority indicating a degree to which the charging or discharging of the self-charging or discharging is prioritized over the charging or discharging of other charging and discharging elements and the received request value, The output characteristic is corrected in such a manner that the upper limit value or the lower limit value of the output range is increased as the priority level is higher, Charging or discharging is performed with an output determined based on a deviation between the system frequency measured at a connection end to the electric power system and a reference frequency of the electric power system and the corrected output characteristic.

2. The charge and discharge control method of the charge and discharge element according to claim 1, wherein: receiving, by broadcasting to all the charging and discharging elements, a difference between a theoretical value of the charging and discharging output of all the charging and discharging elements and an actual value of the charging and discharging output of all the charging and discharging elements measured in the power system, corresponding to a deviation between an actual measured value of the system frequency when each of the charging and discharging elements is charged or discharged with the determined output characteristic and the reference frequency, The output characteristic is corrected in the following manner, that is, when the received difference value indicates that the actual value is higher than the theoretical value, the frequency adjustment capacity is reduced, and when the received difference value indicates that the actual value is lower than the theoretical value, the frequency adjustment capacity is increased.

3. The charge and discharge control method of the charge and discharge element according to claim 2, wherein: The time change rate of the received difference is calculated, and the output characteristic is corrected in the following manner, that is, when the sign of the calculated time change rate is positive, the frequency adjustment capacity is reduced, and when the sign of the calculated time change rate is negative, the frequency adjustment capacity is increased.

4. The charge and discharge control method of the charge and discharge element according to claim 2, wherein: The rate of change of the received difference caused by the deviation between the actual measured value of the system frequency and the reference frequency, i.e., the frequency deviation change rate, is calculated, and the output characteristic is corrected in the following manner, that is, when the sign of the calculated frequency deviation change rate is positive, the frequency adjustment capacity is reduced, and when the sign of the frequency deviation change rate is negative, the frequency adjustment capacity is increased.

5. The charge and discharge control method of a charge and discharge element according to any one of claims 1 to 4, wherein: The request values ​​broadcasted and divided into a charging side and a discharging side are received, and based on the received request values ​​of the charging side and the discharging side, the output characteristics are determined and corrected respectively on the charging side and the discharging side, and charging is performed with the output determined based on the output characteristics of the charging side after the correction, and discharging is performed with the output determined based on the output characteristics of the discharging side after the correction.

6. The charge and discharge control method of a charge and discharge element according to any one of claims 1 to 4, wherein: The charging control element among the multiple charging and discharging elements determines and corrects the output characteristic in which the output range only exists on the charging side, and determines, based on the priority and the received request value, to set the output characteristic to set the lower limit value of the output range only on the charging side to be greater than or equal to the value of the basic power that is always supplied to the dark current load.

7. A charge and discharge control device for a charge and discharge element, wherein: The charge and discharge control device of the charge and discharge element comprises: a receiving unit for receiving a request value of a frequency adjustment capacity corresponding to a system frequency of the electric power system, which is broadcasted to a plurality of charging and discharging elements connected to electric wires of the electric power system; a priority calculation unit that calculates a priority indicating a degree to which charging or discharging of the own charging or discharging element is prioritized over charging or discharging of other charging or discharging elements; a characteristic determination unit that determines an output characteristic of charging and discharging with respect to the system frequency based on the priority level and the request value; a characteristic correction unit that corrects the output characteristic so that an upper limit value or a lower limit value of an output range is increased as the priority level is higher; and A control unit controls the charging or discharging output of the electric power system to an output determined based on a deviation between the system frequency measured at a connection end with respect to the electric wire and a reference frequency of the electric power system and the corrected output characteristic.

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