Price determination device, power control system, price determination method, and program

Abstract

A price determination device (2) according to the present disclosure comprises: a price determination unit (24) that uses a system status prediction result, which is a result of prediction of the status of compliance to a system operation constraint at an arbitrary position in an electrical grid, to determine, as a variable price, the price of electricity for purchase and / or the price of electricity for sale in a facility that performs charging and / or discharging of an EV (7); and an information output unit (23) that outputs, for presentation to the user of the EV (7), variable price information which indicates the variable price, wherein the price of electricity for purchase is a unit price of power for when the EV (7) is charged, and the price of electricity for sale is a unit price of power for when the EV (7) is discharged.

Description

Price determination device, power control system, price determination method and program

[0001] The present disclosure relates to a price determination device, a power control system, a price determination method, and a program for determining the price of electricity.

[0002] As global warming countermeasures are promoted, it is expected that electric vehicles (EVs) will be introduced in large numbers. The cost of charging an EV depends on the unit price of purchased electricity, and the profits gained from discharging an EV depend on the unit price of sold electricity.

[0003] Patent Literature 1 (Patent Literature 1) assumes that demand response control of the power grid will be implemented in the future and discloses a technology for supporting demand response control of the power grid, in which a charging station has a buffer battery for charging multiple batteries and EV batteries, and charges these when electricity prices are low, thereby reducing the cost of charging EV batteries. The energy navigation control device described in Patent Literature 1 effectively navigates an EV to a charging station so that the EV can use a battery or buffer battery that has been charged when electricity prices are low. Specifically, the energy navigation control device described in Patent Literature 1 determines a charging station that is reachable from the EV's current location based on the remaining energy level and energy efficiency of the EV's battery and that has the same type of battery or buffer battery as the EV.

[0004] JP 2011-197932 A

[0005] The current trend toward renewable energy sources (primarily photovoltaic (PV) power generation, but also including wind farms (WF)), which are naturally variable renewable energy sources (hereinafter referred to as renewable energy or naturally variable power sources), is expected to be significantly increased in the future. The load fluctuations due to the charging of electric vehicles (EVs) may be superimposed on the output fluctuations of these sources. This may lead to improper conditions in the power grid, such as congestion (overload, where the current exceeds the allowable value (transmission capacity or distribution capacity) of the transmission and distribution lines) and voltage violations (voltages outside the appropriate range). Furthermore, grid congestion due to increased demand during certain periods (e.g., summer or winter) or certain time periods (e.g., nighttime) is also expected to occur. If power generation and distribution facilities are constructed to meet peak demand during certain periods or certain time periods, the capacity factor may be significantly reduced, resulting in increased social costs.

[0006] The technology described in Patent Document 1 may be able to alleviate the tight power supply and demand situation to some extent by adjusting the timing of battery charging at charging stations, but it cannot address system congestion (overload), deviations of voltage from the appropriate range, etc. It is desirable to resolve inappropriate conditions in the power system (violations of system operation constraints) such as system congestion (overload) and voltage violations (deviations from the appropriate voltage range) while suppressing a decrease in facility utilization rate.

[0007] The present disclosure has been made in consideration of the above, and aims to provide a price determination device that can eliminate inappropriate conditions in the power system while suppressing a decrease in facility utilization rate.

[0008] In order to solve the above-mentioned problems and achieve the object, the price determination device according to the present disclosure includes a price determination unit that determines at least one of the power purchase price and the power sale price as a variable price at a facility that performs at least one of charging and discharging electric vehicles, using a system status prediction result that is a prediction result of compliance with system operation constraints at any point in the electric power system, and an information output unit that outputs variable price information indicating the variable prices. The power purchase price is the unit price of electricity when charging an electric vehicle, and the power sale price is the unit price of electricity when discharging an electric vehicle.

[0009] The price determination device according to the present disclosure has the effect of being able to eliminate inappropriate conditions in the power grid while suppressing a decrease in the capacity factor.

[0010] FIG. 11 is a diagram showing an example of the configuration of a power control system according to the first embodiment. FIG. 12 is a diagram showing an example of a terminal device installed in a charging station according to the first embodiment. FIG. 13 is a diagram showing an example of a price determination processing procedure in a price determination device according to the first embodiment. FIG. 14 is a diagram showing another example of the configuration of a price determination device according to the first embodiment. FIG. 15 is a diagram showing an example of a display screen for DP price information in a terminal device according to the first embodiment. FIG. 16 is a diagram showing another example of the configuration of a price determination device according to the first embodiment.

[0011] A price determination device, a power control system, a price determination method, and a program according to embodiments will be described in detail below with reference to the accompanying drawings.

[0012] First Embodiment. FIG. 1 is a diagram illustrating an example of the configuration of a power control system according to a first embodiment. The power control system of this embodiment includes a power system control device 1, a price determination device 2, and one or more charging stations 6. The charging stations 6 are an example of facilities that perform at least one of charging and discharging of EVs 7. There is no restriction on the number of charging stations 6, as long as there is one or more. The price determination device 2 of this embodiment determines the unit price of electricity when at least one of charging and discharging an EV 7, which is an electric vehicle, at the charging station 6 is performed by dynamic pricing (DP) based on the status of each point in the power system, i.e., the compliance status of system operation constraints at any point in the power system. Hereinafter, the unit price determined by the price determination device 2 is also referred to as a DP price or a variable price. The DP price is at least one of the electricity purchase (charging) price, which is the unit price of electricity purchased by a user of the EV 7 when charging the EV 7 at the charging station 6, and the electricity sale (discharge) price, which is the unit price of electricity sold by a user of the EV 7 when discharging the EV 7 at the charging station 6. The electricity purchase (charging) price is the unit price of electricity when charging the EV 7, and the electricity sale (discharge) price is the unit price of electricity when discharging the EV 7. Note that both the electricity purchase (charging) price and the electricity sale (discharge) price can be zero or a negative value.

[0013] The user of the EV 7 is, for example, the owner of the EV 7, but is not limited to the owner of the EV 7 and may be a user who rents and uses the EV 7. Hereinafter, the electricity purchase (charging) price will also be referred to as the electricity purchase price, and the electricity selling (discharging) price will also be referred to as the electricity selling price.

[0014] The charging station 6 includes charging and discharging equipment for charging and discharging the EV 7. Some of the charging stations 6 may include only charging equipment for charging the EV 7. Alternatively, the charging station 6 may include only discharging equipment for discharging the EV 7, separate from the charging equipment. The charging station 6 may be a stand-alone facility, or may be a facility installed in a public facility, a service area (SA) or parking area (PA) on a highway, a commercial facility such as a department store, or the like. When multiple charging stations 6 are included in the power control system of this embodiment, the multiple charging stations 6 may be a mixture of these.

[0015] The power system control device 1, the price determination device 2, the renewable energy forecasting system 3, the power generation planning system 4, the power demand forecasting system 5, the charging station 6, the EV 7, and the user terminal 8 are communicatively connected via a communication network. The user terminal 8 is a terminal device used by a user of the EV 7. The communication network may be a single communication network or a combination of multiple communication networks. The communication network may be a wired communication network, a wireless communication network, or a mixed wired and wireless communication network. The charging station 6, the EV 7, and the user terminal 8 are examples of recipients of information regarding the DP price determined by the price determination device 2. It is sufficient that at least some of the charging station 6, the EV 7, and the user terminal 8 are capable of receiving information regarding the DP price; it is not necessary for all of the charging station 6, the EV 7, and the user terminal 8 to receive information regarding the DP price.

[0016] The renewable energy prediction system 3, the power generation planning system 4, and the power demand prediction system 5 may be part of an EMS (Energy Management System) installed in, for example, a central load dispatching center, a power grid load control center, or a local load dispatching center, or may be a system linked to the EMS for supply and demand control in the EMS. Furthermore, the renewable energy prediction system 3 and the power demand prediction system 5 may be part of a system such as a SCADA (Supervisory Control And Data Acquisition) installed in a power grid load dispatching center, a power dispatching center, or the like, or a DAS (Distribution Automation System), or may be a system linked to these.

[0017] The renewable energy forecasting system 3 predicts renewable energy output, i.e., the amount of power generated by renewable energy power generation facilities, and transmits the prediction result to the power system control device 1 as a renewable energy output forecast result. The power generation planning system 4 creates operation plans for power plants other than renewable energy plants, i.e., nuclear power plants, thermal power plants, hydroelectric power plants, etc., and transmits the created operation plans to the power system control device 1 as power plant operation plans. Hereinafter, power plants other than renewable energy plants will also be referred to as conventional power plants. The power demand forecasting system 5 predicts power demand and transmits the prediction result to the power system control device 1 as a power demand forecast result. The renewable energy forecasting system 3 can use any method for predicting renewable energy output, and a general method can be used, so a detailed description will be omitted. The power generation planning system 4 can use any method for creating power plant operation plans, and a general method can be used, so a detailed description will be omitted. The power demand forecasting system 5 can use any method for predicting power demand, and a detailed description will be omitted. Note that both the renewable energy output and the output of conventional power plants are power generation outputs, and these are collectively referred to as power generation amounts.

[0018] The power system control device 1 may be, for example, a device such as a SCADA or DAS installed in a central system dispatching center or a dispatching center. The power system control device 1 predicts the status of the power system using the renewable energy output forecast result received from the renewable energy forecasting system 3, the power plant operation plan received from the power generation planning system 4, the power demand forecast result received from the power demand forecasting system 5, and the topology and impedance of the power system, and transmits the prediction result to the price determination device 2. Specifically, the power system control device 1 predicts the status of the power system by, for example, performing power flow calculations, optimal power flow calculations, etc., using the renewable energy output forecast result, the power plant operation plan, the power demand forecast result, and the topology and impedance of the power system. However, the method for predicting the status of the power system is not limited to these examples. The topology and impedance of the power system may be set in advance, or may be automatically input to the power system control device 1 from an external system (not shown) via a database of an external system (not shown), such as an EMS, SCADA, DAS, or digital twin system.

[0019] The status of the power system (compliance with system operation constraints at any point in the power system) indicates whether the power system is in an appropriate state. The status of the power system is, for example, the distribution of power flow and voltage in the power system. Each point (node) in the power flow and voltage distribution may be, for example, a substation, a section switch, a pole transformer, or a consumer, but may be a combination of these or is not limited to these. For example, for a charging station 6, the power flow and voltage may be calculated for each consumer corresponding to the charging station 6. The power system control device 1 predicts the power system status for one day for each 30-minute time slot, for example. However, the prediction period for the power system control device 1 is not limited to one day. Here, the time resolution of the prediction, i.e., the length of the time slot, is set to 30 minutes, which is the same as the time unit of one transaction in the wholesale electricity market. However, the time resolution of the prediction is not limited to this and may be 15 minutes, 1 hour, or the like. The time unit of transactions in the wholesale electricity market is also not limited to 30 minutes. The time resolution of the prediction may be the same as or different from the time unit of one transaction in the wholesale electricity market. Normally, the input data used for the calculation (power supply and demand situation forecast results, renewable energy output forecast results, etc.) are integrated values, so the status of the power grid is calculated as an integrated value, but this is not limited thereto, and the status of the power grid may be an instantaneous value or other statistical quantity (average, median, mode, maximum, minimum, percentile, etc.).

[0020] The price determination device 2 includes an information acquisition unit 21, a storage unit 22, an information output unit 23, and a price determination unit 24. The information acquisition unit 21 acquires information from other devices by communicating with the other devices. For example, the information acquisition unit 21 acquires a prediction result of the status of the power system (the status of each point in the power system) from the power system control device 1, and stores the acquired prediction result of the status of the power system (hereinafter also referred to as a system status prediction result) in the storage unit 22.

[0021] The storage unit 22 stores the forecast results of the power system status, the base price, performance information used to determine the DP price, etc. The base price is a price that serves as a reference price before the price determination unit 24 raises or lowers the DP price.

[0022] The price determination unit 24 uses the grid status prediction results to determine, as the DP price, at least one of the power purchase price and the power sale price at the charging station 6 that charges and / or discharges the EV 7. Specifically, the price determination unit 24 uses the power grid status prediction results stored in the storage unit 22 to determine a DP price so as to resolve an inappropriate state of the power grid, and outputs DP price information indicating the determined DP price to the information output unit 23. The price determination unit 24 also stores the determined DP price in the storage unit 22. An inappropriate state of the power grid is a state in which at least one of grid congestion and voltage violation occurs. The following mainly describes an example in which the price determination device 2 determines both the power purchase price and the power sale price as the DP price; however, the price determination device 2 may determine only the power purchase price or only the power sale price. Details of the method for determining the DP price will be described later.

[0023] The information output unit 23 outputs information by communicating with other devices. For example, the information output unit 23 outputs DP price information. Specifically, the information output unit 23 transmits the DP price information to at least some of the charging stations 6, the EVs 7, and the user terminals 8. This allows the price determination device 2 to present DP prices to users. Note that while FIG. 1 illustrates an example in which the price determination device 2 transmits the DP price information to at least some of the charging stations 6, the EVs 7, and the user terminals 8, the price determination device 2 may transmit the DP price information to another device, such as a web server, and the other device may transmit the DP price information to at least some of the charging stations 6, the EVs 7, and the user terminals 8. That is, the price determination device 2 may present DP prices to users via another device.

[0024] FIG. 2 is a diagram showing an example of a terminal device installed in the charging station 6 of this embodiment. The charging station 6 includes, for example, the terminal device 60 shown in FIG. 2. The terminal device 60 includes a transmission / reception unit 61, an input reception unit 62, and a display unit 63. The transmission / reception unit 61 transmits and receives information by communicating with other devices. For example, the transmission / reception unit 61 receives DP price information from the price determination device 2 and outputs the received DP price information to the display unit 63. As described above, the DP price information may be transmitted from the price determination device 2 to the terminal device 60 via another device. The input reception unit 62 receives input from a user. The input reception unit 62 may, for example, receive an input instructing switching of the screen displayed on the display unit 63.

[0025] The display unit 63 displays the DP price information received from the transmitting / receiving unit 61. The display unit 63 may also display information other than the DP price information. Note that, although an example in which the terminal device 60 includes the input receiving unit 62 is shown in FIG. 2, the terminal device 60 does not necessarily have to be provided with the input receiving unit 62.

[0026] The EV 7 is equipped with a terminal device similar to the charging station 6, and the configuration and functions of this terminal device are similar to those of the terminal device 60 shown in Fig. 2, for example, and it is capable of displaying DP price information. Note that the terminal device equipped in the EV 7 may be realized by an in-vehicle device having other functions, such as a car navigation system.

[0027] The configuration and functions of the user terminal 8 are similar to those of the terminal device 60 shown in Fig. 2, and the user terminal 8 can display DP price information. The user terminal 8 is, for example, a smartphone, a tablet, or a personal computer.

[0028] Next, the operation of the price determination device 2 of this embodiment will be described. Figure 3 is a flowchart showing an example of a price determination processing procedure in the price determination device 2 of this embodiment. As shown in Figure 3, the price determination device 2 acquires a prediction result of the power system status (step S1). In detail, the information acquisition unit 21 receives the prediction result of the power system status from the power system control device 1 and stores the received prediction result of the power system status in the storage unit 22.

[0029] The price determination device 2 determines whether an event requiring action, such as at least one of grid congestion and voltage violation, will occur (step S2). Specifically, the price determination unit 24 reads the predicted results of the power grid status stored in the storage unit 22 and determines whether the predicted results for the time period for which the DP price is to be determined indicate that at least one of grid congestion and voltage violation will occur. The time period for which the DP price is to be determined may be the most recent time period or a time period after the most recent time period. For example, if the time resolution of the predicted results of the power grid status is 30 minutes, the time period for which the DP price is to be determined may be the most recent 30 minutes or the next 30 minutes after the most recent 30 minutes. Furthermore, the price determination device 2 may determine the DP price up to 24 hours in advance one day in advance, or the weekly DP price one week in advance. The time period for which the DP price is to be determined may be determined by, for example, evaluating the status of each point in the power grid after a DP price was previously set, or by other methods.

[0030] The price determination unit 24 may also determine whether an action-requiring event will occur using prediction results for multiple time slices, i.e., multiple time periods. For example, if a voltage violation occurs in a certain time slice but is resolved in the next time slice, the price determination device 2 may determine that an action-requiring event has not occurred. That is, the price determination device 2 may determine that an action-requiring event has occurred if a voltage violation occurs in a predetermined number of consecutive time slices or more. Similarly, the price determination device 2 may determine that an action-requiring event has occurred if system congestion (overload) occurs in a predetermined number of consecutive time slices or more. Note that the threshold, i.e., the number of allowable time slices, may be changed depending on the degree of overload. The price determination device 2 may also determine that an action-requiring event has occurred if at least one of system congestion and a voltage violation occurs in a time slice a certain time after the time slice corresponding to the time period for which the DP price is to be determined.

[0031] If an action-requiring event occurs (step S2: Yes), the price determination device 2 determines the power purchase (charging) price and the power selling (discharging) price so as to resolve the action-requiring event (step S3). In detail, the price determination unit 24 changes the power purchase (charging) price and the power selling (discharging) price from the reference price stored in the storage unit 22. The reference price may be the normal unit price of electricity in the wholesale electricity market or the like, a price calculated from the normal unit price of electricity, the currently set DP price, or a price calculated by statistically analyzing performance information obtained from past DP price settings.

[0032] Specifically, for example, in the case of a radial grid, if there is a large demand for electricity at the end (usually the load end) (i.e., there is a power shortage), the purchase price and sale price of the electricity at the charging station 6 are increased to alleviate the shortage. Also, if there is a large amount of electricity generated by renewable energy or the like at the end (usually the load end) (i.e., there is a power surplus), the purchase price and sale price of the electricity at the charging station 6 are decreased to alleviate the shortage.

[0033] 4 and 5 are diagrams illustrating grid congestion in this embodiment. In the examples shown in FIGS. 4 and 5 , a load and a renewable energy power generation facility (abbreviated as renewable energy in the figures) are connected to a power station B. In the example shown in FIG. 4 , an increase in the power consumption of the load connected to power station B, i.e., an increase in the power demand corresponding to power station B, causes grid congestion with respect to the power flow from power station A to power station B. In such a case, for example, the purchase price and sale price of the power of the charging station 6 connected to power station B are increased. This makes it possible to reduce the number of EVs 7 charging at the charging station 6 connected to power station B and increase the number of EVs 7 discharging at the charging station 6, thereby reducing the power flow from power station A to power station B.

[0034] In the example shown in Figure 5, an increase in the amount of power generated by renewable energy connected to power station B, i.e., an increase in renewable energy power generation corresponding to power station B, causes grid congestion with respect to the power flow from power station B to power station A. In such a case, for example, the power purchase price and power sale price of the charging station 6 connected to power station B are reduced. This makes it possible to increase the number of EVs 7 charging at the charging station 6 connected to power station B and reduce the number of EVs 7 discharging at the charging station 6, thereby reducing the power flow from power station B to power station A.

[0035] Furthermore, if a voltage violation occurs in which the voltage is higher than the appropriate range, the electricity purchase price and electricity sale price of the charging station 6 connected to that location are reduced. This makes it possible to increase the number of EVs 7 charging at the charging station 6 connected to the location where the voltage violation occurs and reduce the number of EVs 7 discharging at that charging station 6, thereby reducing the voltage. Furthermore, if a voltage violation occurs in which the voltage is lower than the appropriate range, the electricity purchase price and electricity sale price of the charging station 6 connected to that location are increased. This makes it possible to reduce the number of EVs 7 charging at the charging station 6 connected to the location where the voltage violation occurs and increase the number of EVs 7 discharging at that charging station 6, thereby raising the voltage.

[0036] In addition, if the power system is complex, the price determination unit 24 may determine, for each event and its location, where and how to adjust the power to achieve an appropriate state by using power flow calculation or optimal power flow calculation. For example, when power flow calculation is used, the price determination unit 24 can determine (predict) which renewable energy power generation facilities and consumers should be adjusted by performing sensitivity calculation. Sensitivity calculation is a method of using a power system model and parameters to change the amount of electricity at various locations in the system and determine the impact of changes in the amount of electricity at a certain location in the power system. For example, the price determination unit 24 calculates the impact of changes in the amount of electricity at various locations on the amount of electricity at the location where the action-requiring event occurs, thereby calculating the location that has the greatest impact on the amount of electricity at the location where the action-requiring event occurs. This allows the price determination unit 24 to determine (predict) which renewable energy power generation facilities and consumers should be adjusted for each location where the action-requiring event occurs. When performing optimal power flow calculation, the price determination unit 24 can determine (predict) which renewable energy power generation facilities and consumers should be adjusted by using the power output of the renewable energy power generation facility and the demand amount of the consumer as variables. Alternatively, in the optimal power flow calculation, the adjustment amount of the power output of the renewable energy power generation facility and the adjustment amount of the demand amount of the consumer may be used as variables, or one of the power output of the renewable energy power generation facility and the demand amount of the consumer may be used as a variable and the adjustment amount of the other may be used as a variable. Also, here, an example will be described in which the price determination unit 24 performs the power flow calculation or the optimal power flow calculation, but a power flow calculation unit may be provided separately from the price determination unit 24, and the power flow calculation unit may perform the power flow calculation or the optimal power flow calculation, and the price determination unit 24 may use the calculation results of the power flow calculation unit to determine where and how to adjust to achieve an appropriate state.

[0037] The DP price may be determined for each charging station 6, or may be determined for each unit in the distribution of power flow and voltage described above, i.e., for each substation, section switch, pole transformer, or consumer. For example, charging stations 6 corresponding to one unit may be treated as one group, and the DP price of the charging stations 6 may be determined for each group.

[0038] The amount of change (increase or decrease) in the DP price may be calculated based on the results of a statistical analysis of the relationship between the amount of change in the DP price and past performance data. The performance data may be, for example, an amount indicating a change in the state of the power grid obtained by setting a DP price. The amount indicating the change in the state of the power grid may be at least one of the amount of change in power flow and the amount of change in voltage at each location when system congestion and voltage violations are resolved by setting a DP price. In other words, the amount indicating the change in the state of the power grid corresponds to the amount of deviation in the system congestion and voltage violations. For example, statistical analysis of the relationship between the amount of change in the DP price and past performance data may be performed to calculate statistical information indicating the relationship between the amount of change in the DP price and the performance data, which is then stored in the storage unit 22. The price determination unit 24 then determines the amount of change in the DP price using the statistical information, the location of the occurrence of the event requiring action corresponding to the period for which the DP price is to be determined, and the amount of deviation.

[0039] Statistical machine learning techniques may also be used as examples of statistical analysis. For example, a trained model for inferring price changes may be generated by supervised machine learning using decision trees, random forests, gradient boosting, k-nearest neighbors, neural networks, support vector machines, deep learning, or the like. Note that statistical machine learning techniques are not limited to these, and other techniques may also be used. These techniques may also be used as classification techniques or regression techniques. When supervised machine learning is used, the feature (input data) may be, for example, at least one of a quantity related to the status of the power grid, a quantity related to timing, and a quantity related to price, and the answer (output data) is the price change. Note that the output data may be the set DP price. Furthermore, various patterns of these feature and output data may all be used as feature (input data), and learning may be performed using evaluation results indicating whether the feature was effective in resolving the inappropriate state of the power grid (e.g., a flag indicating whether it was effective, a value indicating the degree of effectiveness, etc.) as output data. Note that the feature and output data are not limited to the above examples.

[0040] When a statistical machine learning method is used as a regression method, the trained model may output the price change amount or the DP price value itself, as described above. When a statistical machine learning method is used as a classification method, discrete groups may be generated for the price change amount or the DP price during training, and the group into which the item falls may be output during inference. Note that when used as a classification method, although only discrete values ​​can be output, it is possible to assign a probability of classification to each group, making it possible to assign information such as prediction reliability. In the training phase, a trained model is generated using multiple training datasets including feature amounts acquired as actual results and price change amounts, which are correct data corresponding to the feature amounts. Note that the training dataset may include actual data (feature amounts) and corresponding DP prices when an action-requiring event in the power system is resolved and returned to an appropriate state after the DP price is set, or actual data and corresponding DP prices both when the action-requiring event is resolved and when it is not resolved may be used.

[0041] As the quantity related to the status of the power system, for example, at least one of the following data can be used: - Predicted value of renewable energy output at each point in the power system (may be a current value or an estimated value) - Predicted value of power demand (including charging and discharging of EVs 7) at each point in the power system (may be a current value or an estimated value) - Power generation plan value of conventional power plants (which may further include predicted interconnection line power flow values) (may be a current value or an estimated value) - Predicted value of the location of the occurrence of an event requiring action and the amount of deviation (may be a current value or an estimated value)

[0042] The predicted value of renewable energy output is a predicted value in the renewable energy output forecast result, the predicted value of power demand is a predicted value in the power demand forecast result, and the planned power generation value of the conventional power plant may be a planned power generation value calculated from the power plant operation plan or may be a planned power generation value calculated by the power generation planning system 4. The information acquisition unit 21 may acquire these data from the power system control device 1 and store them in the memory unit 22, or the information acquisition unit 21 may acquire them from the renewable energy forecasting system 3, the power generation planning system 4, and the power demand forecasting system 5 and store them in the memory unit 22. The predicted values ​​of the location of the occurrence of the action-requiring event and the deviation amount may be acquired by the information acquisition unit 21 from the power system control device 1 and stored in the memory unit 22, or the price determination unit 24 may acquire information indicating the distribution of power flow and voltage in the power system from the power system control device 1 and calculate the values ​​using the information. Furthermore, when current values ​​are used for each data, power metering results may be used. Furthermore, when estimated values ​​are used for each data, each data may be estimated by the corresponding renewable energy forecasting system 3, power generation planning system 4, and power demand forecasting system 5, or by the power system control device 1, or by a device not shown.

[0043] The predicted value of charge and discharge of the EV 7 is predicted based on, for example, past performance data. For example, the predicted value of charge and discharge of the EV 7 may be predicted from past performance data by day of the week or by time period, or may be predicted by supervised machine learning using information affecting charge and discharge (which may include information obtainable from the EV, such as the charging status (SoC: State of Charge), travel speed, and location of the EV) as input data and the actual value of charge and discharge as output data, or may be predicted by other methods.

[0044] Furthermore, at least one of the following data can be used as a time-related quantity: Month, day, and time (or time zone); Extra-atmospheric theoretical solar radiation intensity; Day of the week; Classification of whether it is a weekday or a weekend or public holiday; Classification of whether it is a special day (New Year's Day, Golden Week, Obon, etc.) or an ordinary day (a day other than a special day).

[0045] The theoretical extra-atmospheric solar radiation intensity is calculated using the formula described in "Meteorology of Water Environments" (edited by Junsei Kondo, Asakura Publishing, 1994). ００ is the solar constant (1365 W / m ２ ), θ is the zenith angle, φ is latitude, δ is the solar declination, h is the hour angle from the solar noon, M is the month, DAY is the day, HOUR is the hour, H ｎ is the meridian time. HOUR is the target time (hours, minutes, and seconds converted into hours). S ｔ =I ００ (d ０ / d) ２ ・cosθ cosθ=sinφsinδ+cosφcosδcosh (d ０ / d) ２ =1.00011+0.034221cosη +0.00128sinη+0.000719cos2η +0.000077sin2η δ=sin －１ (0.398sina ２ ) a ２ =4.871+η+0.033sinη η=(2π / 365)・i i=30.36・(M-1)+DAY h=(HOUR-H ｎ ) 15°

[0046] Furthermore, as the quantity related to the price, at least one of the following data can be used: the current electricity purchase price; the current electricity selling price.

[0047] Note that the features in the training dataset at the time of generating the trained model currently indicate the point in time corresponding to the training dataset, and the current electricity purchase price and current electricity sale price are the prices immediately before the price change corresponding to the correct data (including when the change amount is 0).

[0048] In the learning phase, when determining a learning dataset in which the actionable event has been resolved after the DP price has been determined, it is necessary to evaluate whether the actionable event has been resolved after the DP price has been determined. This evaluation may use measured values ​​in the power system, values ​​estimated using the measured values, or other methods. Furthermore, since the impact of the DP price is not apparent immediately after the DP price is determined, the evaluation may be performed using data from a predetermined period after the DP price has been determined. The predetermined period may be, for example, 30 minutes from the time the price determination device 2 determines and outputs the DP price, but is not limited to this. This predetermined period may be the same as or different from the time unit of one session in the wholesale electricity market. Furthermore, since it may take some time for the DP price to be reflected in user behavior after the DP price is presented, taking this time delay into consideration, for example, the performance data may be data obtained during a predetermined period after the DP price has been presented. This time delay may be determined by accumulating and evaluating the performance data. Furthermore, before performance data is acquired, the time delay may be determined based on the results of a trial run, may be determined based on the performance of other countries, or may be determined by simulation, etc. Furthermore, if 24-hour DP prices are predicted and presented, for example, one week or one day in advance, there is a possibility that there is no time delay because the user has viewed the information and decided on their actions in advance. Therefore, time delay does not need to be taken into consideration. In other words, the specified period may be 0 minutes.

[0049] The output data of the trained model may be both the power purchase price and the power sale price. Alternatively, a trained model using the power purchase price as output data and a trained model using the power sale price as output data may be generated, and the power purchase price and the power sale price may be determined using different trained models. Furthermore, when determining only the power purchase price, it is sufficient to generate a trained model using the power purchase price as output data, and when determining only the power sale price, it is sufficient to generate a trained model using the power sale price as output data. As described above, the price determination unit 24 may determine the DP price using a trained model generated by supervised machine learning for inferring the DP price from a feature that is at least one of a quantity related to the status of the power grid, a quantity related to time, and a quantity related to price.

[0050] After step S3, the price determination device 2 outputs the DP price information (step S4). Specifically, the price determination unit 24 generates DP price information indicating the DP price determined in step S3 and transmits the generated DP price information to at least some of the charging stations 6, EVs 7, and user terminals 8. As described above, the price determination device 2 may transmit the DP price information to at least some of the charging stations 6, EVs 7, and user terminals 8 via another device.

[0051] The method by which the price determination unit 24 determines the price is not limited to the above example. For example, a reinforcement learning method such as Monte Carlo Tree Search (MCTS) or Q-learning can also be used. When using a reinforcement learning method, for example, the state set is the status of the power system (the location and deviation amount of an action-requiring event), the action set is the power purchase price and the power sale price, and after the price is determined, if no action-requiring event occurs, the reward value is increased, and if an action-requiring event occurs, the reward value is decreased. In this case, the reward value is also determined using, for example, data for a specified period after the DP price is determined, similar to the evaluation in supervised machine learning. The specified period is similar to the above example and may be the same as or different from the time unit of one frame in the wholesale electricity market. Furthermore, a time delay may be taken into account, similar to the evaluation in supervised machine learning.

[0052] In the learning phase, the state changes dynamically due to actions, and a reward is given according to the change in state. By repeating this process, a course of action that increases the reward value is learned as a trained model. When the price determination unit 24 determines a price, the state is input into the trained model, thereby obtaining actions appropriate to the state, i.e., the power purchase price and power sale price. Note that, in this case, only the power sale price may be learned and only the power sale price may be determined, or only the power purchase price may be learned and only the power purchase price may be determined. As described above, the price determination unit 24 may determine the DP price using a trained model generated by reinforcement learning, in which the state set is information indicating the status of each point in the power system before the variable price is determined, the action set is the variable price, and the reward is determined based on the status of each point in the power system after the variable price is determined.

[0053] The method by which the price determination unit 24 determines the price is not limited to the example described above, and any method may be used.

[0054] If no event requiring action occurs (No in step S2), the price determination device 2 proceeds to step S4. In this case, the DP price in the DP price information becomes the base price.

[0055] Through the above process, the DP price is presented to the user. FIG. 6 is a diagram showing an example of a display screen of DP price information on the terminal device 60 according to the present embodiment. In the example shown in FIG. 6 , the DP price information includes information indicating the electricity purchase (charging) price and the electricity sale (discharging) price as the DP price, and the electricity purchase (charging) price and the electricity sale (discharging) price are respectively displayed. The DP price information is similarly displayed on the terminal device of the EV 7 and the user terminal 8. Note that FIG. 6 is an example, and the method of displaying the DP price information is not limited to the example shown in FIG. 6 . Furthermore, the display format may be different between the terminal device 60 in the charging station 6, the terminal device in the EV 7, and the user terminal 8.

[0056] In general, it is expected that charging of EVs 7 will be encouraged when the electricity purchase (charging) price is low and charging of EVs 7 will be suppressed when the electricity purchase (charging) price is high. It is also expected that discharging of EVs 7 will be suppressed when the electricity sale (discharging) price is low and discharging of EVs 7 will be encouraged when the electricity sale (discharging) price is high. Therefore, when an event requiring action occurs in the power system, the price determination device 2 can resolve the inappropriate state of the power system by determining the electricity purchase (charging) price and the electricity sale (discharging) price so as to resolve the event requiring action.

[0057] In the example shown in FIG. 1 , the power system control device 1 and the price determination device 2 are provided separately, but the price determination device may be integrated with the power system control device. FIG. 7 is a diagram showing another example of the configuration of the price determination device of this embodiment. Components having the same functions as those in the example shown in FIG. 1 are assigned the same reference numerals as in FIG. 1 , and redundant explanations will be omitted. In the example shown in FIG. 7 , the power system control device 1a includes a system control unit 31 that calculates a system status prediction result by predicting the status of each point in the power system using the predicted power generation amount and the predicted power demand amount, and also includes the information acquisition unit 21, storage unit 22, information output unit 23, and price determination unit 24 of the price determination device 2 shown in FIG. 1 . That is, in the example shown in FIG. 7 , the power system control device 1a is the price determination device. The predicted power generation amount is a prediction result of power generation that takes into account both power generation by renewable energy and power generation other than renewable energy, and is calculated based on the renewable energy output prediction result and the power plant operation plan.

[0058] Fig. 8 is a flowchart showing an example of a price determination process procedure in the power system control device 1a shown in Fig. 7. As shown in Fig. 8, the power system control device 1a acquires a renewable energy output prediction result from the renewable energy prediction system 3 (step S11). In detail, the information acquisition unit 21 receives the renewable energy output prediction result from the renewable energy prediction system 3 and stores the received renewable energy output prediction result in the storage unit 22.

[0059] The power system control device 1a also acquires a power plant operation plan from the power generation planning system 4 (step S12). Specifically, the information acquisition unit 21 receives the power plant operation plan from the power generation planning system 4 and stores the received power plant operation plan in the storage unit 22. The power system control device 1a also acquires a power demand forecast result from the power demand forecasting system 5 (step S13).

[0060] In detail, the information acquisition unit 21 receives the power demand forecast result from the power demand forecasting system 5 and stores the received power demand forecast result in the storage unit 22. Note that the order of steps S11 to S13 is not limited to the example shown in Fig. 8. Also, two or more of steps S11 to S13 may be performed simultaneously.

[0061] The power system control device 1a predicts the status of the power system (step S14). Specifically, the system control unit 31 predicts the status of the power system using the renewable energy output forecast results, the power plant operation plan, the power demand forecast results, and the power system topology and impedance stored in the storage unit 22, and stores the prediction result in the storage unit 22. The power system topology and impedance may be set in advance, as in the example shown in FIG. 1 , or may be automatically input to the power system control device 1a from an external system (not shown) via a database of an external system such as an EMS, SCADA, DAS, or digital twin system. Steps S2 and beyond are the same as in the example shown in FIG. 3. As described above, the power system control device 1a may function as the price determination device of this embodiment.

[0062] Next, the hardware configuration of the price determination device 2 and the power system control device 1a will be described. In the present embodiment, the price determination device 2 functions as the price determination device 2 when a program (computer program) describing the processing of the price determination device 2 is executed on the computer system. Similarly, in the present embodiment, the power system control device 1a functions as the power system control device 1a when a program describing the processing of the power system control device 1a is executed on the computer system. FIG. 9 is a diagram showing an example of the configuration of a computer system that realizes the price determination device 2 and the power system control device 1a of the present embodiment. As shown in FIG. 9, this computer system includes a control unit 101, an input unit 102, a storage unit 103, a display unit 104, a communication unit 105, and an output unit 106, which are connected via a system bus 107.

[0063] In FIG. 9 , the control unit 101 is a processor such as a CPU (Central Processing Unit) that executes a program describing the processing of the price determination device 2 or the power system control device 1a. The input unit 102 is composed of, for example, a keyboard, a mouse, etc., and is used by a user of the computer system to input various information. The memory unit 103 includes various memories such as RAM (Random Access Memory) and ROM (Read Only Memory) and a storage device such as a hard disk, and stores programs to be executed by the control unit 101, necessary data obtained during processing, etc. The memory unit 103 is also used as a temporary storage area for programs. The display unit 104 is composed of a display, LCD (Liquid Crystal Display), etc., and displays various screens to the user of the computer system. The communication unit 105 is a receiver and transmitter that perform communication processing. The output unit 106 is, for example, a printer. Note that FIG. 9 is an example, and the configuration of the computer system is not limited to the example of FIG. 9 . For example, the computer system may not include the display unit 104 and the output unit 106.

[0064] Here, an example of the operation of the computer system until the program of this embodiment is ready to be executed will be described. In the computer system having the above configuration, for example, the program is installed into an auxiliary storage device that is part of the storage unit 103 from a CD-ROM or DVD-ROM inserted in a CD (Compact Disc)-ROM drive or DVD (Digital Versatile Disc)-ROM drive (not shown). Then, when the program is executed, the program read from the auxiliary storage device of the storage unit 103 is stored in the main storage area of ​​the storage unit 103. In this state, the control unit 101 executes processing as the price determination device 2 or the power system control device 1a of this embodiment in accordance with the program stored in the storage unit 103.

[0065] In the above description, a program describing the processing in each of the price determination device 2 and the power system control device 1a is provided using a CD-ROM or DVD-ROM as a recording medium, but this is not limited to this. Depending on the configuration of the computer system, the capacity of the program to be provided, etc., it is also possible to use a program provided via a transmission medium such as the Internet via the communication unit 105.

[0066] The price determination unit 24 shown in FIGS. 1 and 7 and the system control unit 31 shown in FIG. 7 are realized by the control unit 101 shown in FIG. 9 executing a program stored in the storage unit 103 shown in FIG. 9. The storage unit 103 is also used to realize the price determination unit 24 and the system control unit 31. The storage unit 22 shown in FIGS. 1 and 7 is part of the storage unit 103 shown in FIG. 9. The information acquisition unit 21 and the information output unit 23 shown in FIGS. 1 and 7 are realized by the communication unit 105 and the control unit 101 shown in FIG. 9. The price determination device 2 may be realized by multiple computer systems. The price determination device 2 may be realized by, for example, a cloud system. The power system control device 1a may be realized by, for example, a cloud system.

[0067] The program of this embodiment, for example, causes a computer system to execute the steps of using the system status prediction results to determine at least one of the purchase price and the sale price of electricity at a charging station 6 that charges and / or discharges EVs 7 as a DP price, and outputting DP price information indicating the DP price.

[0068] As described above, in this embodiment, the price determination device 2 and the power system control device 1a determine at least one of the power purchase price and the power sale price at the charging station 6 based on the status of each point in the power system. This makes it possible to eliminate inappropriate conditions in the power system while suppressing a decrease in the facility utilization rate.

[0069] Second Embodiment. FIG. 10 is a diagram illustrating a configuration example of a power control system according to a second embodiment. The power control system according to this embodiment is similar to the power control system according to the first embodiment, except that it includes a price determination device 2a instead of the price determination device 2. The price determination device 2a determines the DP price using traffic information acquired from a traffic system 9. The traffic system 9 may also be included in the power control system. The traffic information includes at least one of congestion information indicating whether or not a road is congested and congestion information indicating whether or not a charging station 6 is congested. The congestion information includes information indicating whether or not a road related to the charging station 6 is congested. The road related to the charging station 6 is a road surrounding the charging station 6, but is not limited to this and may be any road on which an EV 7 is expected to travel heading to the charging station 6. Components having the same functions as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and redundant description will be omitted. The following mainly describes differences from the first embodiment.

[0070] The transportation system 9 transmits traffic information to the price determination device 2a. The price determination device 2a is similar to the price determination device 2 of the first embodiment except that it includes a price determination unit 24a instead of the price determination unit 24. In this embodiment, the information acquisition unit 21 receives traffic information from the transportation system 9 and stores the received traffic information in the storage unit 22. Note that here, an example is described in which the price determination device 2a receives traffic information including traffic congestion information and congestion information from the transportation system 9. However, the method of acquiring the traffic congestion information and congestion information is not limited to this example. For example, the price determination device 2a may receive traffic congestion information from the transportation system 9 and congestion information from each charging station 6. Furthermore, for example, the price determination device 2a may acquire traffic congestion information and congestion information from a user terminal 8 or a terminal device included in the EV 7. For example, the price determination device 2a can determine whether the user is riding in the EV 7 based on the traveling speed and location of the user terminal 8, and can estimate whether congestion is occurring based on the traveling speed when the user is riding in the EV 7. The price determination device 2a can also estimate whether or not a traffic jam is occurring based on the travel speed of the EV 7 obtained from the terminal device provided in the EV 7. For example, the price determination device 2a can also determine whether or not the charging station 6 is congested by determining whether or not the EV 7 is charging or waiting to be charged based on the location of the user terminal 8 or the EV 7, and calculating the waiting time.

[0071] Alternatively, for example, each charging station 6 may include a management device that manages the congestion status, and the management device may transmit congestion information to the price determination device 2a. This management device may be the terminal device 60 described in the first embodiment. Whether a charging station 6 is congested is determined, for example, by whether the congestion level is equal to or greater than a threshold. The congestion level is, for example, the ratio of the number of charging / discharging equipment in use to the total number of charging / discharging equipment installed at the charging station 6. In this case, the threshold may be, for example, 1 or 0.8, and is not limited to these values ​​and may be set as desired. The congestion level may also be the number of EVs 7 waiting to be charged or discharged, the waiting time for charging or discharging, or the like. When these are used as the congestion level, a threshold is set for determining congestion based on the number of EVs 7 waiting to be charged or discharged or the waiting time. Note that the congestion level is not limited to the above example.

[0072] The price determination unit 24a determines a DP price using the traffic information and outputs DP price information indicating the determined DP price to the information output unit 23. Note that the price determination unit 24a may determine the DP price using the traffic information without using the predicted result of the power grid status, or may determine the DP price using the predicted result of the power grid status and the traffic information. That is, the processing of this embodiment may be performed in addition to the processing of the first embodiment, or the processing of this embodiment may be performed independently. When the processing of this embodiment is performed in addition to the processing of the first embodiment, for example, the processing of this embodiment is performed after the DP price is determined by the processing of the first embodiment.

[0073] 11 is a flowchart showing an example of a price determination procedure in the price determination device 2a of this embodiment. As shown in FIG. 11, the price determination device 2a acquires traffic information from the traffic system 9 (step S21). Specifically, the information acquisition unit 21 receives the traffic information from the traffic system 9 and stores the received traffic information in the storage unit 22.

[0074] The price determination device 2a determines whether the charging station 6 is congested (step S22). Specifically, the price determination device 2a determines whether the charging station 6 is congested by using congestion information in the traffic information stored in the storage unit 22. If there are multiple charging stations 6, the price determination device 2a determines Yes in step S22 if even one charging station 6 is congested.

[0075] If the charging station 6 is congested (step S22: Yes), the power purchase (charging) price of the congested charging station 6 is increased and the power selling (discharging) price is decreased (step S23). Specifically, the price determination unit 24a increases the power purchase (charging) price and decreases the power selling (discharging) price from the base price stored in the storage unit 22. The base price may be the normal unit price of electricity in the wholesale electricity market, a price calculated from the normal unit price of electricity, the currently set DP price, or a price calculated by statistically analyzing performance information obtained from past DP price settings. Furthermore, if the processing of FIG. 11 is performed after determining the DP price through the processing of the first embodiment, the base price may be the DP price determined through the processing of the first embodiment. In this case, since the DP price has already changed due to the current situation causing congestion, the amount of change in the DP price may be changed taking into account the resulting changes in the situation. The amount of change in the price (increase or decrease) in step S23 may be a predetermined fixed value or may be determined based on past performance. As in the first embodiment, whether or not the congestion has been resolved is evaluated, and the amount of change in price when the congestion is resolved may be learned by supervised machine learning or reinforcement learning. After step S23, step S4 is performed as in the first embodiment.

[0076] If the charging station 6 is not congested (No in step S22), the price determination device 2a determines whether or not there is road congestion (step S24). Specifically, the price determination device 2a uses the congestion information in the traffic information stored in the storage unit 22 to determine whether or not there is road congestion in the area where the charging station 6 constituting the power control system of the present embodiment is located.

[0077] If the road is congested (step S24: Yes), the price determination device 2a increases the electricity purchase (charging) price and decreases the electricity selling (discharging) price of the charging station 6 associated with the congested road (step S25), and the price determination device 2a proceeds to step S4. In step S25, specifically, the price determination unit 24a increases the electricity purchase (charging) price and decreases the electricity selling (discharging) price from the reference price stored in the storage unit 22. The reference price is the same as the reference price described in relation to step S23. Similarly to step S23, the price change amount (increase amount, decrease amount) in step S25 may be a predetermined fixed value or may be determined based on past performance. As in the first embodiment, whether the congestion has been resolved may be evaluated, and the price change amount when the congestion is resolved may be learned by supervised machine learning or reinforcement learning.

[0078] If the road is not congested (No in step S24), the price determination device 2a proceeds to step S4. In this case, the DP price in the DP price information becomes the base price.

[0079] While the example in which the processing of the first embodiment is performed first has been given, this is not limiting and the processing of the second embodiment may be performed first before the processing of the first embodiment. The order of steps S23 and S25 described above may also be reversed. The DP price determined in the processing of the first embodiment and the DP price determined in the processing of the second embodiment may cancel each other out. In such a case, the DP price may be determined by finding a solution using an optimization method. For example, the processing of the first embodiment corresponds to performing an operation related to the total amount of an entire area having a certain size, while the processing of the second embodiment corresponds to performing an operation related to an amount limited to a smaller, relatively local area. Therefore, the optimal allocation of these may be solved using an optimization method.

[0080] Fig. 12 is a diagram showing an example of a display screen of DP price information on the user terminal 8 in this embodiment. In the example shown in Fig. 12 , the DP price information includes information indicating the power purchase (charging) price and the power sale (discharging) price as the DP price, and the power purchase (charging) price and the power sale (discharging) price are displayed for each charging station 6. Similarly, the terminal device in the EV 7 also displays the display screen shown in Fig. 12 , for example. Similarly, the terminal device 60 in the charging station 6 may display the power purchase (charging) price and the power sale (discharging) price for each charging station 6, or may display only the power purchase (charging) price and the power sale (discharging) price for that charging station 6.

[0081] The display order of the charging stations 6 may be an order set by the user himself / herself (an order determined in settings such as favorite charging stations 6 or frequently used charging stations 6). Alternatively, the display order of the charging stations 6 may be an order of proximity to the user's current location (position). For example, the DP price for each charging station 6 may be displayed in order of proximity to the user's current location (position) along with the distance from the current location. The display order of the charging stations 6 may be rearranged by the price determination device 2a or by the user terminal 8 or the terminal device of the EV 7 that displays the charging stations.

[0082] FIG. 13 is a diagram showing another example of a display screen of DP price information on the user terminal 8 according to the present embodiment. In the example shown in FIG. 13 , the locations of the charging stations 6 are displayed on a map, and the electricity purchase (charging) price and electricity sale (discharging) price for each charging station 6 are displayed. Similarly, the terminal device 60 in the EV 7 also displays the display screen shown in FIG. 13 . Similarly, the terminal device 60 in the charging station 6 may display the display screen shown in FIG. 13 , or may display only the electricity purchase (charging) price and electricity sale (discharging) price for that charging station 6. Note that FIGS. 12 and 13 are merely examples, and the display method of the DP price information is not limited to the examples shown in FIGS. 12 and 13 . Furthermore, the display formats may differ between the terminal device 60 in the charging station 6, the terminal device in the EV 7, and the user terminal 8.

[0083] Through the above processing, the price determination device 2a indirectly controls the behavior of users of EVs 7, alleviates congestion at charging stations 6, and can alleviate congestion on roads and prevent traffic jams. Note that the impact of congestion at charging stations 6 may differ for each charging station 6, so the amount of price change may be changed for each charging station 6. Similarly, the impact of congestion may differ for each road, so the amount of price change may be changed depending on the road on which congestion occurs.

[0084] 11 , the DP price is changed both due to congestion at the charging station 6 and due to road congestion. However, this is not limiting and only one of these may be performed. That is, the price determination unit 24a may determine the DP price corresponding to the charging station 6 based on the congestion status of the charging station 6, or may determine the DP price corresponding to the charging station 6 based on the congestion status of the road related to the charging station 6, or may perform both of these. When both are performed, there is a possibility that the elimination of road congestion and the elimination of congestion at the charging station 6 may mutually affect each other, such as when the elimination of road congestion causes congestion at the charging station 6, or when the elimination of congestion at the charging station 6 causes road congestion. Therefore, instead of dividing the processing into steps S22 and S23 and steps S24 and S25, the DP price may be determined for each charging station 6 by taking both of these into consideration. For example, the effect of elimination of road congestion and the effect of elimination of congestion at the charging station 6 may be evaluated, and then a priority may be determined, and the DP price may be determined based on the result of the evaluation. 11, steps S22 and S23 are performed before steps S24 and S25, but steps S24 and S25 may be performed before steps S22 and S23. Also, in the example shown in Fig. 11, the price determination unit 24a determines both the power purchase price and the power sale price, but also in the present embodiment, the price determination unit 24a may determine either the power purchase price or the power sale price.

[0085] The price determination device 2a of this embodiment is realized by a computer system, similar to the price determination device 2 of embodiment 1. Furthermore, the power system control device 1a of embodiment 1 shown in Fig. 7 may be provided with the price determination unit 24a of this embodiment instead of the price determination unit 24, so that the power system control device 1a performs the processing described in this embodiment.

[0086] As described above, in the present embodiment, the price determination device 2a determines at least one of the electricity purchase price and the electricity sale price at the charging station 6 based on at least one of whether the charging station 6 is congested and whether road congestion exists. By determining the DP price based on whether the charging station 6 is congested, it is possible to alleviate the congestion at the charging station 6, and by determining the DP price based on whether road congestion exists, it is possible to alleviate the congestion on the road.

[0087] Third Embodiment. Figure 14 is a diagram showing an example of the configuration of a power control system according to a third embodiment. The power control system of this embodiment is similar to the power control system of the first embodiment, except that it includes a price determination device 2b instead of the price determination device 2 and adds a price disclosure system 10. The price determination device 2b determines and outputs DP prices as in the first or second embodiment, and calculates predicted values ​​of DP prices up to a certain period in the future, i.e., using the results of a system status prediction for the certain period ahead. The price disclosure system 10 publishes the predicted results of DP prices. Components having the same functions as those in the first embodiment are assigned the same reference numerals as in the first embodiment, and redundant explanations will be omitted. Below, differences from the first embodiment will be mainly explained.

[0088] The price determination device 2b is similar to the price determination device 2 of the first embodiment, except that it includes a price determination unit 24b instead of the price determination unit 24. The price determination unit 24b calculates predicted DP prices for a certain period of time, such as one day, one week, or one month, using the same processing as in the first or second embodiment. The certain period is not limited to one day, one week, or one month. The time resolution of the predicted DP prices is the same as or higher than the time resolution of the DP prices published in the price publication system 10. In other words, the time resolution of the predicted DP prices when published may be the same as or coarser than the predicted DP prices. For example, the time resolution of the predicted DP prices may be 30 minutes, as in the current wholesale electricity market, and the time resolution of the predicted DP prices when published may be coarser than 30 minutes. The price determination device 2b may also update the predicted DP prices for one day to the previous day. In this case, the price determination device 2b may change the predicted value of the DP price immediately beforehand, taking into account the influence of prediction errors such as sudden changes in weather or demand. The price determination device 2b outputs the calculated predicted value as the DP price predicted value to the information output unit 23. The information output unit 23 outputs the DP price predicted value to the price disclosure system 10.

[0089] The price disclosure system 10 publishes a predicted DP price for a certain period. The predicted DP price may be published by the price disclosure system 10 together with a weather forecast for a certain period. For example, the price disclosure system 10 may publish a weekly predicted DP price in the news or on the Internet, like a weekly weather forecast. Alternatively, the price disclosure system 10 may publish the predicted DP price together with the weekly weather forecast in the news or on the Internet. The time resolution of the predicted DP price when published may be the same as that of the predicted DP price transmitted from the price determination device 2b, or may be coarser than that of the predicted DP price transmitted from the price determination device 2b. The predicted DP price may also be transmitted from the price determination device 2b or the price disclosure system 10 to at least some of the charging stations 6, the EVs 7, and the user terminals 8. For example, the predicted DP price may be transmitted from the price determination device 2b or the price disclosure system 10 to at least some of the charging stations 6, the EVs 7, and the user terminals 8 together with predicted information on the charging stations 6 and road congestion.

[0090] FIG. 15 is a diagram showing an example of a display screen for the predicted DP price value according to the present embodiment. When the price disclosure system 10 publishes the predicted DP price value on the Web, the predicted DP price value may be displayed in chronological order on the user terminal 8 or another terminal, as shown in FIG. 15 . As described above, the predicted DP price value may also be displayed together with a weekly weather forecast or the like. Note that FIG. 15 is merely an example, and is not intended to be limiting. For example, placing a cursor such as a mouse pointer on the time-series line shown in FIG. 15 may display values ​​(values ​​on the X-axis (date and time) and the Y-axis (price)). Furthermore, the display format is not limited to the graph shown in FIG. 15 . For example, when a charging station 6 to be displayed is selected in units of time resolution, the date and time, the power purchase price, and the power sale price may be displayed in a table format. For example, a table in which the date and time are listed instead of the column for the charging station 6 in the table shown in FIG. 12 may be displayed. The display method for the predicted DP price value is not limited to these examples.

[0091] Although the example in which the price disclosure system 10 is provided separately from the price determination device 2b has been described in FIG. 14, the price determination device 2b may have the function of the price disclosure system 10.

[0092] The price determination device 2b of this embodiment is realized by a computer system, similar to the price determination device 2 of embodiment 1. Furthermore, the power system control device 1a of embodiment 1 shown in Fig. 7 may be provided with the price determination unit 24b of this embodiment instead of the price determination unit 24, so that the power system control device 1a performs the processing described in this embodiment.

[0093] As described above, in this embodiment, the price determination device 2b calculates the predicted value of the DP price for a certain period of time ahead, and the price disclosure system 10 discloses the predicted value. This makes it easier for the user of the EV 7 to plan charging of the EV 7, improving user convenience and enabling at least one of charging and discharging of the EV 7 to be performed at a more appropriate time.

[0094] Fourth Embodiment. FIG. 16 is a diagram showing an example of the configuration of a power control system according to a fourth embodiment. The power control system of this embodiment is similar to the power control system of the first embodiment, except that it includes a price determination device 2c instead of the price determination device 2 and adds an EV management system 11 that aggregates and stores EV information, which is information about EVs 7. The price determination device 2c determines and outputs DP prices, as in at least one of the first, second, and third embodiments, and creates a charge / discharge plan for the EVs 7 using the EV information. Components having the same functions as those in the first embodiment are assigned the same reference numerals as those in the first embodiment, and redundant explanations will be omitted. The following mainly describes the differences from the first embodiment.

[0095] The EV information stored by the EV management system 11 includes, for example, at least one of the behavioral pattern of the user of the EV 7, the travel history of the EV 7, the state of charge (SoC) of the EV 7, and power consumption during travel by the EV 7. The behavioral pattern of the user of the EV 7 is information that reveals the pattern of travel by the user using the EV 7. The behavioral pattern of the user of the EV 7 may be information input by the user of the EV 7 using the user terminal 8, a terminal device provided in the EV 7, or the travel history (location history) of the user terminal 8 held by the user. For example, a user who commutes to work or school using the EV 7 may input their behavior using the EV 7, such as the day of the week, the time they arrive at work or school, and the time they leave work or school, as a behavioral pattern. Alternatively, the user of the EV 7 may input the planned dates and times of travel using the EV 7, as well as the departure and destination points of the travel, as a weekly, monthly, or other schedule. The EV management system 11 receives the behavior pattern of the user of the EV 7 from the user terminal 8 and thereby acquires the behavior pattern of the user of the EV 7 .

[0096] The movement history of the EV 7 is a history of the location of the EV 7, and may be acquired, for example, by a terminal device provided in the EV 7. As described in the first embodiment, the terminal device of the EV 7 that displays the DP price information may also function as a car navigation system, and in this case, the terminal device may acquire the location history of the EV 7. The EV management system 11 acquires the movement history of the EV 7, for example, by receiving the movement history of the EV 7 from the EV 7.

[0097] The charging status of the EV 7 is the status of the storage battery mounted on the EV 7. For example, the EV management system 11 acquires the status of the storage battery mounted on the EV 7 by receiving the charging status of the EV 7 from an on-board device that manages the storage battery mounted on the EV 7. Furthermore, the power consumption of the EV 7 while traveling is, for example, the power consumed by discharging the storage battery mounted on the EV 7. For example, the EV management system 11 acquires the power consumption of the EV 7 while traveling by receiving the power consumption of the EV 7 while traveling from an on-board device that manages the storage battery mounted on the EV 7.

[0098] The EV management system 11 may use a power consumption history acquired over a certain period of time as the power consumption of the EV 7 while it is moving, or may use an average or median value over the certain period of time as the power consumption of the EV 7 while it is moving. The certain period of time may be, for example, several hours, but is not limited to this. Alternatively, for example, the EV management system 11 may manage both an average (or median) value over the last few hours and an average (or median) value over a longer period of time as the power consumption of the EV 7 while it is moving, and use either of these values ​​depending on the conditions (occasions). Alternatively, the EV management system 11 may store average fuel efficiency (catalog values) according to vehicle type or model, receive the vehicle type or model from the EV 7, and calculate the fuel efficiency from the received vehicle type or model, thereby calculating the power consumption of the EV 7 while it is moving. Alternatively, the EV management system 11 may collect data on multiple EVs 7, statistically calculate fuel efficiency based on the vehicle type, location, and time, and calculate the fuel efficiency according to the vehicle type, location, and time. For example, fuel efficiency is related to temperature, but fuel efficiency also varies depending on the time of year due to various factors, such as traffic congestion during the New Year holidays and the use of air conditioning depending on the season. Therefore, taking the time of year into consideration allows for more accurate calculations of fuel efficiency.

[0099] The price determination device 2c is similar to the price determination device 2 of the first embodiment, except that it further includes a charge / discharge plan creation unit 25. Note that the following mainly describes an example in which the price determination device 2c performs the same processing as in the first embodiment and further performs processing to create a charge / discharge plan, but as described above, the price determination device 2c may also perform the same processing as in the second or third embodiment and further perform processing to create a charge / discharge plan.

[0100] In the present embodiment, the information acquisition unit 21 receives EV information from the EV management system 11 and stores the received EV information in the storage unit 22. Furthermore, the storage unit 22 pre-stores map information including information indicating the locations of the charging stations 6. The map information may be updated as appropriate. The map information also includes information indicating the location of the user's base of the EV 7, such as the home, workplace, or school of the user. The user's base of the EV 7 is basically a location where the EV 7 is parked for an extended period of time and serves as the starting point for the EV 7's travel. Here, an example is described in which the map information includes information indicating the location of the user's base of the EV 7. However, the present invention is not limited to this. The information indicating the location of the user's base of the EV 7 may be acquired separately from the map information, for example, from the user terminal 8 or a terminal device included in the EV 7, and stored in the storage unit 22. The charge / discharge plan creation unit 25 creates a charge / discharge plan using, for example, the predicted results of the power system status by time period, the unit price of electricity or the predicted value of the unit price of electricity when purchasing (charging) and selling (discharging) electricity at a location other than the charging station 6, such as at home, work, or school, the DP price or the predicted value of the DP price determined by the price determination device 2c, EV information, and map information.

[0101] For example, in order to avoid impairing user convenience, charge / discharge plan creation unit 25 creates a charge / discharge plan for each EV 7, specifying where and how much to charge and discharge, taking into consideration the charge time and discharge time, etc. For example, the charge / discharge plan creation unit 25 creates a charge / discharge plan including a plan for at least one of charging and discharging the EV 7, using at least one of the behavior pattern of the user of the EV 7, the movement history of the EV 7, the charging status of the EV 7, and the power consumption while the EV 7 is moving, the unit price of electricity when at least one of charging and discharging the EV 7 is performed at a location other than the charging station 6, and the DP price.

[0102] More specifically, for example, the charge / discharge plan creation unit 25 creates a charge / discharge plan by solving an optimization problem using the unit price of electricity or the predicted unit price of electricity when purchasing (charging) and selling (discharging) electricity at the user's base of the EV 7, the DP price or the predicted value of the DP price determined by the price determination device 2c, EV information, map information, the fuel efficiency of the EV 7 (amount of electricity used per unit distance), and the charge time and discharge time. In this case, for example, the variables in the optimization problem are the charge amount and discharge amount at each time (time in the time resolution unit of the charge / discharge plan), and the objective function may be the total cost for the period for which the charge / discharge plan is created, or may be calculated using the total cost for the period for which the charge / discharge plan is created and the time required for the user to travel by the EV 7. The total cost is, for example, the sum of the costs required for charging minus the profit obtained from discharging. In this case, the charge / discharge plan creation unit 25 solves the optimization problem to minimize the total cost.

[0103] The charge / discharge plan creation unit 25 outputs the created charge / discharge plan to the information output unit 23, and the information output unit 23 outputs the charge / discharge plan to the corresponding user terminal 8 or EV 7. The information output unit 23 may also output the charge / discharge plan to the charging station 6. Alternatively, the information output unit 23 may transmit the charge / discharge plan to the EV management system 11, and the EV management system 11 may transmit the charge / discharge plan to the corresponding user terminal 8 or EV 7. The charge / discharge plan creation unit 25 may create a charge / discharge plan when, for example, a user of the EV 7 requests creation of a charge / discharge plan, or may periodically create a charge / discharge plan for an EV 7 corresponding to a pre-registered user. The charge / discharge plan creation unit 25 may also perform a reservation process to reserve a charging station 6 based on the charge / discharge plan.

[0104] Although the example described above is one in which a charge / discharge plan is created taking into consideration both charging and discharging of the EV 7, the charge / discharge plan creation unit 25 may create a charge plan indicating where and how much to charge. For example, the charge / discharge plan creation unit 25 may create a charge plan on the assumption that the EV 7 will not be discharged at the charging station 6 or the like, i.e., on the assumption that the power stored in the storage battery of the EV 7 will be used by the EV 7. Furthermore, the charge / discharge plan creation unit 25 may create a discharge plan that indicates where and how much to discharge without considering charging.

[0105] 16 illustrates an example in which the EV management system 11 is provided separately from the price determination device 2c, but the price determination device 2c may have the function of the EV management system 11. Also, a terminal device provided in the EV 7 may have a charge / discharge plan creation unit 25, collect information in the same way as the price determination device 2c, and create a charge / discharge plan.

[0106] The price determination device 2c of this embodiment is realized by a computer system, similar to the price determination device 2 of embodiment 1. Furthermore, by adding a charge / discharge plan creation unit 25 to the power system control device 1a of embodiment 1 shown in Fig. 7, the power system control device 1a may be configured to perform the processing described in this embodiment.

[0107] The charge / discharge plan created by the above process can reduce the cost burden on the user. Furthermore, the charge / discharge plan created by the above process is likely to be particularly effective for users who are likely to use the EV 7 in the same manner every day, such as users who use the EV 7 to commute to work or school.

[0108] Fifth Embodiment. FIG. 17 is a diagram illustrating a configuration example of a power control system according to a fifth embodiment. The power control system of this embodiment is similar to the power control system of the first embodiment, except that it includes a price determination device 2d instead of the price determination device 2 and an EV management system 11a that aggregates and stores business-use EV information, which is information about business-use EVs 7. Examples of business-use EVs 7 include, but are not limited to, trucks operated by a transportation company and buses used to transport passengers. The price determination device 2d determines and outputs DP prices, as in at least one of the first, second, and third embodiments, and creates a charge / discharge plan for the EVs 7 using the business-use EV information. Components having the same functions as those in the first embodiment are designated by the same reference numerals as those in the first embodiment, and redundant explanations will be omitted. Differences from the first embodiment will be mainly described below.

[0109] The business-use EV information stored by the EV management system 11a includes, for example, at least one of the following: the operating route of the EV 7, the travel history of the EV 7, the charging status of the EV 7, the power consumption of the EV 7 while traveling, and information about the driver's rest. The rest information (information about the driver's rest) includes, for example, at least one of the driver's rest interval, rest duration, and number of rests. The operating route of the EV 7 and the information about the driver's rest may be input into the EV management system 11a by, for example, an operator or manager of the business, or may be estimated from the past stopping locations and stopping times of the EV 7. Furthermore, the rest information may be the legally required rest interval, rest duration, and number of rests. In this case, the rest information does not need to be included in the business-use EV information and may be stored in advance in the storage unit 22 of the price determination device 2d.

[0110] The methods of acquiring the movement history of the EV 7, the charging state of the EV 7, and the power consumption of the EV 7 while it is moving are the same as those in the fourth embodiment.

[0111] The price determination device 2d is similar to the price determination device 2 of the first embodiment except for the addition of a charge / discharge plan creation unit 25a. The following mainly describes an example in which the price determination device 2d performs the same processing as in the first embodiment and also performs processing to create a charge / discharge plan. However, as described above, the price determination device 2d may perform the same processing as in the second or third embodiment and also perform processing to create a charge / discharge plan. Furthermore, the charge / discharge plan creation unit 25a may create a charge / discharge plan for a general user's EV 7 (an EV other than the business EV 7 of the present embodiment) by processing similar to that of the fourth embodiment, and may also create a charge / discharge plan for the business EV 7 by processing in the present embodiment. For example, the EV management system 11 may have the function of the EV management system 11a of the present embodiment, or the EV management system 11a may be provided in addition to the EV management system 11, and the charge / discharge plan creation unit 25 of the fourth embodiment may perform both the processing in the fourth embodiment and the processing in the present embodiment.

[0112] In the present embodiment, the information acquisition unit 21 receives commercial EV information from the EV management system 11a and stores the received commercial EV information in the storage unit 22. The storage unit 22 also stores map information including information indicating the locations of charging stations 6. The map information may be updated as appropriate. The map information may also include information indicating the locations of bases for the EVs 7. The bases for the EVs 7 may be parking lots, logistics centers, sales offices, etc., of the business operators that manage the EVs 7. Here, an example is described in which the map information includes information indicating the locations of the bases for the EVs 7. However, this is not limiting, and the information may also be included in the commercial EV information. The charge / discharge plan creation unit 25a creates a charge / discharge plan using, for example, the predicted results of the power grid status by time period, at least one of the unit price of electricity or the predicted value of the unit price of electricity when charging or discharging at the bases for the EVs 7, the DP price or the predicted value of the DP price determined by the price determination device 2d, the commercial EV information, and the map information.

[0113] For example, the charge / discharge plan creation unit 25a creates a charge / discharge plan for each EV 7, specifying where and how much charging and discharging should be performed, taking into consideration information about the driver's rest in addition to the charging time and discharging time. For example, the charge / discharge plan creation unit 25a creates a charge / discharge plan including a plan for at least one of charging and discharging the EV 7, using at least one of the driving route of the EV 7, the movement history of the EV 7, the charging status of the EV 7, and the power consumption during movement of the EV 7, information about the rest of the driver of the EV 7, the unit price of electricity when at least one of charging and discharging the EV 7 is performed at a location other than the charging station 6, and the DP price. More specifically, for example, the charge / discharge plan may be created so that at least a part of the time for charging and discharging the EV 7 is set as the driver's rest time. For example, the charge / discharge plan creation unit 25a creates a charge / discharge plan by solving an optimization problem using the unit price of electricity or the predicted unit price of electricity when the EV 7 purchases (charges) and sells (discharges) electricity at its base, the DP price or the predicted value of the DP price determined by the price determination device 2d, the commercial EV information, the map information, the fuel efficiency (amount of electricity used per unit distance) of the EV 7, and the charge time and discharge time. In this case, for example, the variables in the optimization problem may be the charge amount and discharge amount at each time (time in the time resolution unit of the charge / discharge plan), and the objective function may be the total cost for the period for which the charge / discharge plan is created. The total cost is, for example, the sum of the costs required for charging minus the profit obtained from discharging. In this case, the charge / discharge plan creation unit 25a solves the optimization problem to minimize the total cost.

[0114] The charge / discharge plan creation unit 25a outputs the created charge / discharge plan to the information output unit 23, and the information output unit 23 transmits the charge / discharge plan to the user terminal 8 of the driver of the corresponding EV 7 or to the EV 7. Alternatively, the information output unit 23 may transmit the charge / discharge plan to the EV management system 11a, and the EV management system 11a may transmit the charge / discharge plan to the corresponding user terminal 8 or EV 7. Note that the charge / discharge plan creation unit 25a may create a charge / discharge plan when, for example, a business operator requests creation of a charge / discharge plan, or may periodically create charge / discharge plans for EVs 7 corresponding to business operators registered in advance.

[0115] Although the example described above is one in which a charge / discharge plan is created taking into consideration both charging and discharging of the EV 7, the charge / discharge plan creation unit 25a may create a charge plan that indicates where and how much charging will be performed. For example, the charge / discharge plan creation unit 25a may create a charge plan on the assumption that the EV 7 will not be discharged at a charging station 6 or the like, i.e., on the assumption that the power stored in the storage battery of the EV 7 will be used by the EV 7. Furthermore, the charge / discharge plan creation unit 25a may create a discharge plan that indicates where and how much discharging will be performed without considering charging. Furthermore, the charge / discharge plan creation unit 25a may perform a reservation process for reserving a charging station 6 based on the charge / discharge plan.

[0116] 17 illustrates an example in which the EV management system 11a is provided separately from the price determination device 2d, but the price determination device 2d may have the function of the EV management system 11a. Also, a terminal device provided in the EV 7 may have a charge / discharge plan creation unit 25a, collect information in the same way as the price determination device 2d, and create a charge / discharge plan.

[0117] The price determination device 2d of this embodiment is realized by a computer system, similar to the price determination device 2 of embodiment 1. Furthermore, by adding a charge / discharge plan creation unit 25a to the power system control device 1a of embodiment 1 shown in Fig. 7, the power system control device 1a may be configured to perform the processing described in this embodiment.

[0118] The charge / discharge plan created by the above process takes into account the driver's break intervals, break duration, number of breaks, etc., and therefore can time the charging and discharging of the EV 7 to coincide with the driver's breaks, optimizing travel time and the total cost of charging and discharging. This reduces the cost burden on business users. Furthermore, in order to address the 2024 problem in the logistics industry, namely the problem caused by the Work Style Reform Bill imposing a cap on driver working hours, legal regulations are scheduled to be strengthened in the future. If the pricing device 2d creates a charge / discharge plan using statutory break intervals, break duration, number of breaks, etc. as information about the driver's breaks, the cost burden on business users can be reduced while complying with legal regulations.

[0119] Sixth Embodiment. FIG. 18 is a diagram illustrating a configuration example of a power control system according to a sixth embodiment. The power control system of this embodiment is similar to the power control system of the first embodiment, except that it additionally includes one or more customer facilities 12, one or more in-motion charging / discharging systems 13, and one or more parking charging / discharging systems 14. The customer facilities 12 are charging / discharging facilities or charging facilities for EVs 7 at power consumers, such as charging / discharging facilities or charging facilities at the homes of EV users, or charging / discharging facilities of businesses that manage the EVs 7. The in-motion charging / discharging systems 13 are, for example, systems that can wirelessly charge and / or discharge the EVs 7 while the EVs are traveling. For example, the in-motion charging / discharging systems 13 may be a charging system that charges the EVs 7 while the EVs are traveling, a discharging system that discharges the EVs 7 while the EVs are traveling, or a charging / discharging system that can both charge and discharge the EVs 7 while the EVs are traveling. The parking charge / discharge system 14 is a system capable of at least one of charging and discharging the EV 7 while the EV 7 is parked in a parking space for the EV 7 installed on a road. For example, the parking charge / discharge system 14 may be a charging system that charges the EV 7 while the EV 7 is parked, a discharging system that discharges the EV 7 while the EV 7 is parked, or a charging / discharging system that can both charge and discharge the EV 7 while the EV 7 is parked. Components having the same functions as those in the first embodiment are assigned the same reference numerals as those in the first embodiment, and redundant description will be omitted. Differences from the first embodiment will be mainly described below.

[0120] In this embodiment, the price determination unit 24 determines the DP price for charging and discharging of the EV 7 in the customer facility 12, the in-motion charging and discharging system 13, and the parking charging and discharging system 14, similar to the charging and discharging at the charging station 6. Each of the customer facility 12, the in-motion charging and discharging system 13, and the parking charging and discharging system 14 is an example of a facility that performs at least one of charging and discharging of the EV 7. As described in the first embodiment, the DP price determined by the price determination unit 24 is for at least one of charging and discharging. Regarding the customer facility 12, it is assumed that the customer facility 12 or a measuring device (not shown) can measure the amount of charging and discharging of the EV 7. In other words, it is assumed that the amount of charging and discharging of the EV 7 can be calculated separately from other power demands and power generation amounts at the customer where the customer facility 12 is installed, thereby enabling settlement based on the DP price. The price determination unit 24 may calculate or settle the DP price not only for the amount of charging and discharging of the EV 7, but also for other demands.

[0121] The price determination unit 24 may determine the DP prices so that the DP prices are the same for the charging station 6, the consumer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14, or may determine the DP prices so that at least some of the DP prices are different. In the latter case, for example, the DP price for each of the charging station 6, the consumer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14 may be determined by performing supervised machine learning, reinforcement learning, or the like, described in the first embodiment, for each type or location of the charging station 6, the consumer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14. Furthermore, the DP price for each combination of the type and location of the charging station 6, the consumer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14 may be determined. Alternatively, the price determination unit 24 may determine the DP price for the charging station 6 in the same manner as in the first embodiment, and then determine the DP prices for other types of facilities using the DP price for the charging station 6. For example, the price determination unit 24 may determine the DP price of other types of equipment by multiplying the DP price for charging station 6 by a predetermined constant, or may determine the DP price of other types of equipment by adding or subtracting a predetermined constant to the DP price for charging station 6.

[0122] 18 shows an example in which the price determination unit 24 also determines the DP prices corresponding to the customer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14, but this is not limiting, and the price determination unit 24 may determine a DP price corresponding to at least one of the customer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14 in addition to the charging station 6. Alternatively, the price determination unit 24 may determine a DP price corresponding to at least one of the customer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14 instead of the charging station 6.

[0123] The parking charge / discharge system 14 is particularly effective for charging and discharging EVs 7 for business use such as long-distance trucks, and by determining the DP price including the parking charge / discharge system 14, EVs 7 that are long-distance trucks can be utilized for supply and demand control.

[0124] Note that in any one of the second, third, fourth, and fifth embodiments, or a combination of two or more of these, a DP price may be determined that corresponds to at least one of the customer facility 12, the in-motion charging / discharging system 13, and the parking charging / discharging system 14 in addition to the charging station 6. Furthermore, the power system control device 1a shown in Fig. 7 of the first embodiment may perform the processing described in this embodiment.

[0125] Seventh Embodiment Fig. 19 is a diagram showing an example of the configuration of a power control system according to a seventh embodiment. The power control system of this embodiment is similar to the power control system of the first embodiment, except that it includes a price determination device 2e instead of the price determination device 2 and adds an EV management system 11b that provides EV management information including information indicating whether an EV 7 is available. The price determination device 2e is similar to the price determination device 2 of the first embodiment, except that it adds a movement control unit 26. Components having the same functions as those of the first embodiment are assigned the same reference numerals as those of the first embodiment, and redundant explanations will be omitted. Below, differences from the first embodiment will be mainly explained.

[0126] The EV management system 11b collects information from the EV 7 to manage the EV 7 and control its movement. For example, the EV management system 11b collects EV status information from the EV 7, including the EV 7's location, charging status, owner information (identification information), and whether the EV 7 is capable of autonomous driving, and uses the EV status information to determine whether the EV is available, i.e., whether it is being used. The EV management system 11b creates EV usage information indicating the availability of the EV 7 based on the determination result of whether the EV 7 is available, and transmits the EV management information including the EV usage information to the price determination device 2e. Alternatively, the owner or driver of the EV 7 may manually input a flag value indicating whether the EV 7 is available, and the EV management system 11b may acquire the flag as EV usage information from a terminal device provided in the EV 7 or the user terminal 8. The EV management information includes, for example, EV usage information and EV information. Furthermore, the EV management system 11b uses the movement information for the EV 7 received from the price determination device 2e to transmit, to the EV 7, control information for moving the autonomously driven EV 7 to the destination indicated by the movement information. The movement information includes, for example, information indicating the location of a charging station 6 or the like that is the destination when the EV 7 is moved to charge or discharge the EV 7, and may also include a route to the destination.

[0127] When the information acquisition unit 21 of the price determination device 2e receives EV management information from the EV management system 11b, it stores the received EV management information in the storage unit 22. When the price determination unit 24 determines a DP price as in the first embodiment, it saves the determined DP price in the storage unit 22. The movement control unit 26 selects a charging station 6 that promotes charging or discharging to resolve an inappropriate state at each point in the power grid and an EV 7 to be moved to the charging station 6 based on the DP price or the grid status prediction result and the location, charging status, and availability of the automatically driven EV 7. The movement control unit 26 also controls the automatic movement of the selected EV 7 to the charging station 6. Specifically, for example, the movement control unit 26 uses the EV management information and DP price stored in the storage unit 22 to select an EV 7 to be moved to a charging station 6 from among available automatically driven EVs 7 so as to resolve the event requiring action. Then, by transmitting movement information for moving the selected EV 7 to the charging station 6 via the information output unit 23 to the EV management system 11 b, control is performed to automatically move the EV 7 to the charging station 6.

[0128] For example, moving an available EV 7 to a charging station 6 with a low electricity purchase price and charging it there can be effective in resolving the event requiring action. Therefore, the movement control unit 26 extracts EVs 7 near charging stations 6 with low electricity purchase prices based on the locations of the EVs 7 and the charging stations 6, and selects, from the extracted EVs 7, EVs 7 that can be charged based on their charging status. For example, the movement control unit 26 selects, as EVs 7 to be moved, EVs 7 that are capable of autonomous driving and have poor charging statuses, i.e., low SoCs, among EVs 7 whose distance from a charging station 6 with a low electricity purchase price is within a predetermined distance value. Whether or not the SoC is low is determined, for example, by whether or not the SoC is equal to or less than a first threshold value. The first threshold value may vary depending on the EV 7. The movement control unit 26 generates control information instructing the selected EV 7 to be moved to the corresponding charging station 6 for charging, and outputs the generated control information to the information output unit 23. Furthermore, the movement control unit 26 may select an EV 7 as a mobile object based on the location and charging status of the EV 7 so that an EV 7 with a good charging status, i.e., a high SoC, is discharged at the charging station 6 .

[0129] The information output unit 23 transmits the control information to the EV management system 11b. Upon receiving the control information, the EV management system 11b controls the EV 7 specified in the control information to move to the charging station 6 at the destination and charge the EV 7.

[0130] Furthermore, the movement control unit 26 may determine the EV 7 to be moved based on the owner information. For example, information indicating whether automatic movement to resolve an event requiring action is permitted for each owner may be registered in advance and stored in the storage unit 22, and the movement control unit 26 may use the information to select the EV 7 to be moved by the above-described method from among the EVs 7 of owners who permit automatic movement to resolve an event requiring action.

[0131] Furthermore, in the above example, an example was described in which an EV 7 to be moved was selected based on the DP price, but the movement control unit 26 may also select an EV 7 to be moved using the predicted results of the power system status instead of the DP price.

[0132] In the above example, the price determination device 2e transmits movement information to the EV management system 11b, and the EV management system 11b controls the EV 7 based on the movement information, but this is not limited to this. The price determination device 2e may control the EV 7 by generating control information for controlling the EV 7 using the movement information and transmitting it to the EV 7.

[0133] Furthermore, after the movement control unit 26 determines the EV 7 to be moved, the price determination unit 24 may predict the status of the power grid again, taking into account charging or discharging by the EV 7, and change the DP price based on the prediction result.

[0134] The price determination device 2e of this embodiment is realized by a computer system, similar to the price determination device 2 of embodiment 1. Furthermore, by adding a movement control unit 26 to the power system control device 1a of embodiment 1 shown in Fig. 7, the power system control device 1a may be configured to perform the processing described in this embodiment.

[0135] Furthermore, in the above example, an example was described in which the power control system of embodiment 1 is equipped with an EV management system 11b and a movement control unit 26 is added to the price determination device 2, but similarly, the power control systems of embodiments 2 to 6 may be equipped with an EV management system 11b and a movement control unit 26 may be added to each of the price determination devices 2, 2a to 2d, thereby allowing the processing described in this embodiment to be performed.

[0136] As described above, in this embodiment, by moving the EV 7 to the charging station 6 and causing it to charge or discharge, it is possible to resolve an improper state of the power grid.

[0137] Eighth Embodiment Fig. 20 is a flowchart showing an example of a price determination process procedure of a power system control device 1a according to an eighth embodiment. The configuration of the power control system according to this embodiment is the same as that of the power control system shown in Fig. 7. In this embodiment, the price determination unit 24 determines the DP price in consideration of control by voltage control equipment in the power system. The voltage control equipment is a voltage regulator, a phase modifying equipment, etc. The voltage regulator is, for example, an LRT (Load Ratio control Transformer: a transformer with on-load tap changer) or an SVR (Step Voltage Regulator). The phase modifying equipment is, for example, a shunt reactor, a static capacitor, an SVC (Static Var Compensator), etc.

[0138] Steps S11 to S14 and S2 to S4 shown in FIG. 20 are the same as steps S11 to S14 and S2 to S4 shown in FIG. 8 of the first embodiment. In this embodiment, if the answer to step S2 is Yes, the power system control device 1a predicts the status of the power system taking voltage control into consideration (step S31). Specifically, the price determination unit 24 performs power flow calculations, optimal power flow calculations, and the like under conditions in which the control variables (including tap positions and on / off of phase modifying devices) of the voltage control equipment are changed to resolve the event requiring action, thereby predicting the status of the power system. In step S3, the DP price is determined based on the prediction result calculated in step S31. Note that in step S31, for example, it may be determined for each voltage control equipment whether a change in the DP price or control by the voltage control equipment is to be prioritized, and the price determination unit 24 may change the control variables for the voltage control equipment that is prioritized over a change in the DP price. For example, the control amount of the voltage control equipment may be converted into a cost, and the cost may be compared with the cost required for changing the DP price to determine whether to prioritize the change in the DP price or the control by the voltage control equipment. Also, by setting a constraint on the control amount of the voltage control equipment changed in step S31, the control amount of the voltage control equipment that takes priority over the change in the DP price may be limited.

[0139] While FIG. 20 illustrates an example that takes voltage control into consideration, if the resolution of system congestion is also considered, adjustment of the power flow and voltage distribution in the power system due to factors such as the suppression of renewable energy output, increases or decreases in storage battery output, and increases or decreases in consumer demand may also be considered. That is, both the process shown in FIG. 20 and processes that take into account the suppression of renewable energy output, increases or decreases in storage battery output, and increases or decreases in consumer demand may be performed. In this case, in step S31, the power system control device 1a further determines the amount of adjustment of the power flow and voltage distribution in the power system to take into account the resolution of the event requiring action, and then predicts the status of the power system reflecting the determined amount of adjustment. Note that adjustable limits may be set in advance for the amount of adjustment of the power flow and voltage distribution in the power system, and the amount of adjustment may be determined within the limits. In step S3, the DP price is determined based on the prediction results calculated in step S31.

[0140] By the above process, in this embodiment, the DP price is determined taking into consideration the control by the voltage control facility. This allows the DP price to be set more appropriately. Note that the process of this embodiment may be combined with any of the second to seventh embodiments.

[0141] The configurations shown in the above embodiments are merely examples, and may be combined with other known technologies, or different embodiments may be combined with each other. It is also possible to omit or modify parts of the configurations as long as they do not deviate from the gist of the invention.

[0142] REFERENCE SIGNS LIST 1, 1a Power system control device, 2, 2a, 2b, 2c, 2d, 2e Price determination device, 3 Renewable energy prediction system, 4 Power generation planning system, 5 Power demand prediction system, 6 Charging station, 7 EV, 8 User terminal, 9 Transportation system, 10 Price disclosure system, 11, 11a, 11b EV management system, 12 Consumer equipment, 13 In-motion charging / discharging system, 14 Parking charging / discharging system, 21 Information acquisition unit, 22 Memory unit, 23 Information output unit, 24, 24a, 24b Price determination unit, 25, 25a Charging / discharging plan creation unit, 26 Movement control unit, 31 System control unit, 60 Terminal device, 61 Transmitting / receiving unit, 62 Input receiving unit, 63 Display unit.

Claims

1. A price determination device comprising: a price determination unit that determines at least one of the power purchase price and power sale price at equipment that performs at least one of charging and discharging of electric vehicles as a variable price using a system status prediction result that is a prediction result of compliance with system operation constraints at any point in the power system; and an information output unit that outputs variable price information that indicates the variable price, wherein the power purchase price is the unit price of electricity when charging the electric vehicle, and the power sale price is the unit price of electricity when discharging the electric vehicle.

2. The price determination device according to claim 1, further comprising a system control unit that calculates the system status forecast result by predicting the status of each point in the power system using the forecast results of power generation amount and power demand.

3. The price determination device according to claim 1 or 2, characterized in that the system status prediction result includes information indicating whether or not an event requiring action will occur, which is at least one of system congestion, in which the current deviates from the allowable value, and voltage violation, in which the voltage deviates from the appropriate range.

4. The price determination device according to claim 3, wherein the price determination unit determines the variable price so as to resolve the event requiring action.

5. A price determination device as described in claim 3 or 4, characterized in that, when the system congestion occurs, the price determination unit increases the power purchase price of the equipment downstream of the flow corresponding to the system congestion, or decreases the power purchase price of the equipment upstream of the flow corresponding to the system congestion.

6. A price determination device as described in claim 3 or 4, characterized in that, when the system congestion occurs, the price determination unit increases the electricity selling price of the equipment downstream of the flow corresponding to the system congestion, or decreases the electricity selling price of the equipment upstream of the flow corresponding to the system congestion.

7. A price determination device as described in any one of claims 1 to 6, characterized in that the price determination unit determines the variable price using a trained model generated by supervised machine learning to infer the variable price from a feature that is at least one of a quantity related to the status of the power system, a quantity related to timing, and a quantity related to price.

8. A price determination device as described in any one of claims 1 to 6, characterized in that the price determination unit determines the variable price using a trained model generated by reinforcement learning, in which a set of states is information indicating the status of each point in the power system before the variable price is determined, a set of actions is a variable price, and a reward is determined based on the status of each point in the power system after the variable price is determined.

9. A price determination device as described in any one of claims 1 to 8, characterized in that the price determination unit determines the variable price corresponding to the facility based on the congestion status of the facility.

10. A price determination device as described in any one of claims 1 to 9, characterized in that the price determination unit determines the variable price corresponding to the facility based on the congestion status of the road related to the facility.

11. A price determination device as described in any one of claims 1 to 10, characterized in that the price determination unit calculates a predicted value of the fluctuation price for a certain period in the future using the system status prediction result for the certain period, and the information output unit outputs the predicted value to a price disclosure system that makes the predicted value public.

12. The price determination device according to claim 11, wherein the predicted value is published by the price publication system together with the weather forecast for the certain period.

13. A price determination device as described in any one of claims 1 to 12, comprising a charge / discharge plan creation unit that creates a charge / discharge plan including a plan for at least one of charging and discharging of the electric vehicle using at least one of the behavioral patterns of the user of the electric vehicle, the movement history of the electric vehicle, the charging status of the electric vehicle, and the power consumption while the electric vehicle is in motion, the unit price of electricity when at least one of charging and discharging of the electric vehicle is performed at a location other than the facility, and the variable price, wherein the information output unit outputs the charge / discharge plan.

14. The price determination device described in claim 13, characterized in that the charge / discharge plan creation unit further creates a charge / discharge plan including a plan for at least one of charging and discharging of the electric vehicle using at least one of the operating route of the electric vehicle for business use, the movement history of the electric vehicle, the charging status of the electric vehicle, and the power consumption while the electric vehicle is in motion, information regarding the rest period of the driver of the electric vehicle, the unit price of electricity when at least one of charging and discharging of the electric vehicle is performed at a location other than the facility, and the variable price.

15. A price determination device as described in any one of claims 1 to 12, comprising a charge / discharge plan creation unit that creates a charge / discharge plan including a plan for at least one of charging and discharging of the electric vehicle using at least one of the operating route of the electric vehicle for business use, the movement history of the electric vehicle, the charging status of the electric vehicle, and the power consumption while the electric vehicle is in motion, information regarding the resting hours of the driver of the electric vehicle, the unit price of electricity when at least one of charging and discharging of the electric vehicle is performed at a location other than the facility, and the variable price, wherein the information output unit outputs the charge / discharge plan.

16. The pricing device according to claim 14 or 15, wherein the information regarding the driver's rest includes the statutory rest interval, rest duration, and number of rest periods.

17. A price determination device according to any one of claims 13 to 16, characterized in that the charge / discharge plan creation unit performs reservation processing for reserving the equipment based on the charge / discharge plan.

18. A pricing device according to any one of claims 1 to 17, wherein the facility includes a charging station.

19. A price determination device according to any one of claims 1 to 18, wherein the facility includes an in-motion charging / discharging system that charges and / or discharges the electric vehicle while the electric vehicle is traveling.

20. A pricing device according to any one of claims 1 to 19, characterized in that the facility includes a parking charging / discharging system that charges and / or discharges the electric vehicle while parked in a parking space.

21. A price determination device as described in any one of claims 1 to 20, characterized in that it comprises a movement control unit that selects the equipment that promotes charging or discharging and the electric vehicle to be moved to the equipment in order to resolve an inappropriate state at each point in the power system based on the variable price or the system status prediction result and the location, charging status, and availability of the autonomously driven electric vehicle, and controls the selected electric vehicle to be automatically moved to the equipment.

22. A power control system comprising: a facility for at least one of charging and discharging electric vehicles; and a price determination device, wherein the price determination device comprises: a price determination unit that determines at least one of the power purchase price and power sale price of the facility as a variable price using a system status prediction result, which is a prediction result of compliance with system operation constraints at any point in the power system; and an information output unit that outputs variable price information indicating the variable price, wherein the power purchase price is the unit price of electricity when charging the electric vehicle, and the power sale price is the unit price of electricity when discharging the electric vehicle.

23. A price determination method in a price determination device, comprising: a step of determining, as a variable price, at least one of the purchase price and the sale price of electricity at a facility that performs at least one of charging and discharging of electric vehicles, using a system status prediction result that is a prediction result of compliance with system operation constraints at any point in the power system; and a step of outputting variable price information that indicates the variable price, wherein the purchase price is the unit price of electricity when charging the electric vehicle, and the sale price is the unit price of electricity when discharging the electric vehicle.

24. A program that causes a computer system to execute the steps of: determining at least one of the power purchase price and power sale price at equipment that charges and / or discharges electric vehicles as a variable price using a system status prediction result that is a prediction result of compliance with system operation constraints at any point in the power system; and outputting variable price information that indicates the variable price, wherein the power purchase price is the unit price of electricity when charging the electric vehicle, and the power sale price is the unit price of electricity when discharging the electric vehicle.

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