Charge and discharge control device

Abstract

This invention provides a charging and discharging control device that controls the charging and discharging power of batteries installed in each vehicle constituting a vehicle group in a manner that follows the required charging and discharging power of the vehicle group. The charging and discharging control device includes a control unit that uses an action prediction model that predicts the movement of the vehicles to predict the remaining capacity of the batteries for each vehicle in a predetermined period. The control unit uses the predicted remaining capacity of the batteries and a battery aging prediction model that predicts the aging of the batteries based on the remaining capacity of the batteries to optimize the indicated value of the charging and discharging power of the batteries for each vehicle in a manner that minimizes the aging of the batteries in each vehicle and the cumulative value of the charging and discharging power of the batteries in each vehicle follows the required value. The control unit then controls the charging and discharging operation of the batteries of each vehicle according to the optimized indicated value.

Description

Technical Field

[0001] This invention relates to a charge / discharge control device. Background Technology

[0002] In recent years, with a focus on linking the function of electric vehicles as batteries with the power infrastructure, the charging and discharging capacity and timing of electric vehicle batteries have been optimized, thereby utilizing electric vehicle batteries as part of a virtual power plant (VPP) (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Publication No. 2013-520942

[0006] However, when charging and discharging the battery without considering the electric vehicle's function as a mobility unit, the energy required for the electric vehicle's movement cannot be guaranteed, and power shortages may occur. Furthermore, charging and discharging the battery without considering its condition may accelerate battery aging. Against this background, there is a need for a technology that suppresses power shortages and battery aging, and ensures that the cumulative charge and discharge capacity of each electric vehicle's battery matches the charging and discharging power requirements of the vehicle group as mandated by the power company and the EMS (Energy Management System). Summary of the Invention

[0007] The present invention was made in view of the above-mentioned problems, and its object is to provide a charging and discharging control device that can suppress power shortage and battery aging, and make the cumulative value of the charging and discharging of the batteries of each electric vehicle follow the required value of the charging and discharging power of the vehicle group.

[0008] The charging and discharging control device of the present invention controls the charging and discharging power of the batteries installed in each vehicle constituting the vehicle group in a manner that follows the required charging and discharging power value for the vehicle group. The device is characterized in that it includes a control unit that uses an action prediction model that predicts the vehicle's movement to predict the remaining battery capacity for each vehicle within a predetermined period. Using the predicted remaining battery capacity and a battery aging prediction model that predicts the aging of the battery based on the remaining battery capacity, the control unit optimizes the indicated charging and discharging power value for each vehicle's battery within the predetermined period in a manner that minimizes the aging of the battery in each vehicle and ensures that the cumulative value of the charging and discharging power of the battery in each vehicle follows the required value. The control unit then controls the charging and discharging operation of the battery in each vehicle according to the optimized indicated value.

[0009] Alternatively, after controlling the charging and discharging actions of each vehicle's battery according to the optimized indicated value, the control unit performs feedback control to correct the deviation between the actual value of the battery's charging and discharging power and the indicated value at a period shorter than the period in which the indicated value was calculated. This structure allows for rapid response.

[0010] Invention Effects

[0011] According to the charging and discharging control device of the present invention, an action prediction model that predicts the movement of the vehicle is used to predict the remaining capacity of the battery for each vehicle in a predetermined period in the future. The battery aging prediction model that predicts the aging of the battery based on the predicted remaining capacity is used to optimize the indicated value of the charging and discharging power of the battery for each vehicle in a predetermined period in such a way that the aging of the battery of each vehicle is minimized and the cumulative value of the charging and discharging power of the battery of each vehicle follows the required value. Therefore, it is possible to suppress power shortage and battery aging, and make the cumulative value of the charging and discharging power of the battery of each electric vehicle follow the required value of the charging and discharging power of the vehicle group. Attached Figure Description

[0012] Figure 1 This is a block diagram illustrating the structure of a charge / discharge control device according to one embodiment of the present invention.

[0013] Figure 2 This is a flowchart illustrating the charge / discharge control process of one embodiment of the present invention.

[0014] Figure 3 This is an example of a graph showing the relationship between battery aging indicators and SOC (State of Charge).

[0015] Explanation of reference numerals in the attached figures

[0016] Train Set Control Server

[0017] 2EMS (Energy Management System)

[0018] 3 power companies

[0019] 4 Chargers and Dischargers

[0020] 5 vehicles

[0021] 11. Vehicle Information Database (Vehicle Information DB)

[0022] 12 Action Prediction Model

[0023] 13 User Input

[0024] 14 Rental Reservation System Detailed Implementation

[0025] Hereinafter, a charge / discharge control device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0026] 〔structure〕

[0027] First, refer to Figure 1 The structure of a charge / discharge control device according to one embodiment of the present invention will be described below.

[0028] Figure 1 This is a block diagram illustrating the structure of a charge / discharge control device according to one embodiment of the present invention. Figure 1 As shown, a charging and discharging control device according to one embodiment of the present invention is a device for realizing a virtual power plant using batteries such as batteries installed in vehicles such as electric vehicles, and includes a vehicle control server 1 composed of information processing devices such as computers.

[0029] The train control server 1 is a device that controls the charging and discharging of the battery installed in the vehicle 5, which is connected to the charger 4, in accordance with the charging and discharging power requirements of the train set obtained from the EMS (Energy Management System) 2 and the power company 3. It should be noted that the charger 4 is connected to the power system via a power line and to the train control server 1 via an information communication line, enabling mutual information communication.

[0030] In this embodiment, the vehicle control server 1 includes a vehicle information database (vehicle information DB) 11. Information related to the vehicle 5, which can control the charging and discharging of the battery, is stored as vehicle information in the vehicle information DB 11. Examples of vehicle information include user information of the vehicle 5, identification information of the vehicle 5, location information of the vehicle 5, information related to the capacity of the battery installed in the vehicle 5 and its current remaining capacity (SOC (State of Charge)), and information related to the upper and lower limits of the SOC of the battery specified by the user of the vehicle 5.

[0031] The vehicle control server 1 has an action prediction model 12 that predicts the future actions (location information, etc.) of each vehicle for which vehicle information is stored in the vehicle information DB 11. Specifically, the action prediction model 12 is a computer program that predicts the future actions of vehicle 5 based on past action data of vehicle 5. It can be constructed through machine learning, for example, using date and weather information as input values ​​and the location information of vehicle 5 corresponding to the input values ​​as the output value. For example, by inputting the date and weather information for predicting the actions of vehicle 5 into the action prediction model 12, the location information of vehicle 5, such as a company, corresponding to the input content can be obtained as the output.

[0032] The vehicle control server 1 can obtain the vehicle 5 utilization reservation information (user input) 13 entered by the user into the predetermined application and the vehicle 5 rental reservation information stored in the rental reservation system 14 via the telecommunication line.

[0033] In a charge / discharge control device with this structure, the charge / discharge control process shown below is executed by the vehicle control server 1 to suppress battery depletion and aging in each vehicle, and to ensure that the cumulative charge / discharge amount of each vehicle's battery follows the required value as the charge / discharge indication value for the vehicle group. Hereinafter, refer to... Figure 2 The process of charge and discharge control processing according to one embodiment of the present invention will be explained.

[0034] [Charge and discharge control processing]

[0035] Figure 2 This is a flowchart illustrating the charge / discharge control process of one embodiment of the present invention. Figure 2 The flowchart shown in the figure begins when the execution command for charging and discharging control processing is input to the train control server 1, and the charging and discharging control processing enters step S1.

[0036] In step S1, the train control server 1 obtains the required charging and discharging power for the trainset within a predetermined future period from EMS2 and the power company 3 via telecommunication lines. It should be noted that EMS2 and the power company 3 calculate the required charging and discharging power for the trainset within a predetermined future period, up to 24 hours later, using a predetermined control cycle of 30 minutes. Thus, step S1 is completed, and the charging and discharging control process proceeds to step S2.

[0037] In step S2, the vehicle control server 1 uses the action prediction model 12, user input 13, and information obtained from the rental reservation system 14 to predict the connection status with the charger 4 and the electrical power required for driving for each vehicle 5 registered in the vehicle information DB11 during a future scheduled period. For example, if there is a scheduled movement of vehicle 5 from its home to the company during the future scheduled period, the vehicle control server 1 predicts that vehicle 5 will be connected to the charger 4 while it is at its home and company, and calculates the electrical power required for vehicle 5 to move from its home to the company using its home and company location information. Thus, step S2 is completed, and the charging and discharging control process proceeds to step S3.

[0038] In step S3, the vehicle group control server 1 sets the charging and discharging power and the upper and lower limits of the battery's SOC for each vehicle 5 as inequality limits for a predetermined period in the future. Furthermore, the vehicle group control server 1 sets an equality limit such that the cumulative value of the indicated charging and discharging power for each vehicle in the predetermined period is equal to the required charging and discharging power for the entire vehicle group in the predetermined period. It should be noted that the vehicle group control server 1 sets the power required for driving predicted in step S2 or the lower limit of the battery's SOC specified by the user as the lower limit of the battery's SOC. Furthermore, the vehicle group control server 1 sets the specified value of the battery's SOC used to avoid full charging and inhibit aging, or the upper limit of the battery's SOC specified by the user, as the upper limit of the battery's SOC. Thus, step S3 is completed, and the charging and discharging control process proceeds to step S4.

[0039] In step S4, the train control server 1 utilizes, for example... Figure 3 The battery aging prediction model shown uses the battery's SOC as input and the battery's aging index as output. It sets an objective function with the predicted SOC of the battery within a predetermined future period as input and the amount of battery aging within that period as output. Thus, step S4 is completed, and the charge / discharge control process proceeds to step S5.

[0040] In step S5, the vehicle control server 1 optimizes the indicated values ​​of charge and discharge power for each vehicle 5 for a predetermined period based on the predicted SOC of the battery over a future predetermined period, while satisfying the constraints set in step S3 and minimizing the value of the objective function set in step S4. It should be noted that at this time, the vehicle control server 1 calculates the predicted SOC of the battery using the current SOC of the battery, the battery capacity, the indicated values ​​of charge and discharge power, the connection status with the charger 4 calculated in step S2, and the electrical power required for driving. Furthermore, the vehicle control server 1 stores the optimized indicated values ​​of charge and discharge power for the future predetermined period as a charge and discharge plan. Thus, step S5 is completed, and the charge and discharge control process proceeds to step S6.

[0041] It should be noted that the vehicle control server 1 can also optimize the charging and discharging power indication value in a way that minimizes the difference between the cumulative value of the charging and discharging power indication value for each vehicle in a future predetermined period and the required value of the charging and discharging power for the vehicle group in a future predetermined period. Furthermore, the vehicle control server 1 can also optimize the charging and discharging power indication value in a way that minimizes the variance of battery aging, thereby reducing unfairness to users relative to battery aging. Additionally, the vehicle control server 1 can also optimize the charging and discharging power indication value in a way that minimizes the power consumption of the vehicle group (the power efficiency of the charger 4, the standby mode of the charger 4, and the power saving in the stop mode).

[0042] In step S6, the vehicle control server 1 controls the charging and discharging of the battery installed in the vehicle according to the charging and discharging plan stored in step S5. Thus, step S6 is completed, and the charging and discharging control process proceeds to step S7.

[0043] It should be noted that when performing steps S2 to S5 on a large number of vehicles over a long period, the computation time becomes longer, sometimes making it impossible to keep up with rapid responses. In a virtual power plant utilizing the batteries of vehicle 5, rapid responses are required to keep up with sudden changes in demand, vehicle entry and exit, LFC (Load Frequency Control), and governor-free operations. Therefore, it is preferable that the vehicle control server 1, in conjunction with the processing in step S6, performs feedback control to correct the difference between the indicated and actual values ​​of the battery's charging and discharging power at a cycle shorter than the computation cycle of steps S2 to S5 (approximately 1 to 10 seconds). Furthermore, it is preferable that the vehicle control server 1 sets a deterioration-tolerant value range for the optimal charging and discharging power of each vehicle obtained through the processing in steps S2 to S5, and corrects the charging and discharging power of each vehicle within this range.

[0044] In step S7, the train control server 1 determines whether it has received a signal indicating the end of the charge / discharge control process. If the result of the determination is that a signal indicating the end of the process has been received (step S7: Yes), the train control server 1 terminates the series of charge / discharge control processes. On the other hand, if no signal indicating the end of the process has been received (step S7: No), the train control server 1 returns the charge / discharge control process to the process in step S1.

[0045] It should be noted that in the next step S1, the train control server 1 can also correct the required charging and discharging power values ​​obtained from EMS2 and power company 3 based on the difference between the actual value of the accumulated charging and discharging power and the required charging and discharging power value for the train. This improves the tracking accuracy of the required charging and discharging power value despite interference such as vehicle entry and exit.

[0046] Based on the above description, it is clear that in the charge and discharge control processing of one embodiment of the present invention, the vehicle group control server 1 uses an action prediction model that predicts the actions of the vehicles 5 to predict the remaining capacity of the battery for each vehicle 5 in a predetermined period. Using the predicted remaining capacity of the battery and a battery aging prediction model that predicts the aging of the battery based on the remaining capacity of the battery, the system optimizes the indicated value of the charge and discharge power of the battery for each vehicle in a predetermined period in such a way that the aging of the battery of each vehicle is minimized and the cumulative value of the charge and discharge power of the battery of each vehicle follows the required value. Therefore, it is possible to suppress power shortage and battery aging, and make the cumulative value of the charge and discharge power of the battery of each electric vehicle follow the required value of the charge and discharge power of the vehicle group.

[0047] The foregoing has described embodiments applicable to the invention carried out by the inventors. However, the present invention is not limited to the description and drawings that constitute a part of the disclosure of this invention. That is, all other embodiments, examples, and techniques applied based on this invention by those skilled in the art are included within the scope of this invention.

Claims

1. A charge / discharge control device for controlling the charge / discharge power of batteries installed in each vehicle constituting the vehicle group in a manner that follows the required charge / discharge power of the vehicle group, characterized in that... The charging and discharging control device includes a control unit. This control unit uses an action prediction model that predicts vehicle movement to predict the remaining battery capacity for each vehicle within a predetermined period. It then uses the predicted remaining battery capacity and a battery aging prediction model that predicts battery aging based on that remaining capacity to optimize the indicated charging and discharging power for each vehicle within the predetermined period, minimizing battery aging and ensuring the cumulative charging and discharging power of each vehicle's batteries follows the required value. Finally, it controls the charging and discharging actions of each vehicle's batteries according to the optimized indicated values. After controlling the charging and discharging actions of the batteries of each vehicle according to the optimized indicated value, the control unit performs feedback control to correct the deviation between the actual value of the charging and discharging force of the battery and the indicated value at a period shorter than the period in which the indicated value is calculated. The control unit sets an acceptable range for the optimal charging and discharging power of each vehicle, and corrects the charging and discharging power of each vehicle within the range of the specified value. The control unit corrects the required charging and discharging power value based on the difference between the actual value of the cumulative charging and discharging power and the required charging and discharging power value for the vehicle group.

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