Charging system

Abstract

To provide a charging system comprising a first charger and a second charger belonging to a contract in which a basic charge determined by a peak value of supplied power and a meter-rate charge according to the amount of power used are charged, and provide a technique to prevent an increase of the basic charge.SOLUTION: A controller of a charging system disclosed in the specification determines a first output pattern of a first charger for charging a first battery from information on the first battery. When a user requesting charging of a second battery appears, the controller determines a second output pattern of a second charger for charging the second battery and the schedule for the start time and the finish time of charging, so that the total output power of the first charger and the second charger does not exceed a predetermined peak setting value. The controller presents the determined schedule to the user of the second battery. When the controller receives a reply from the user approving the charging on the schedule, it charges the second battery according to the schedule.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a charging system capable of charging two batteries. [Background technology]

[0002] One type of power receiving contract for receiving power from an electric power company is one in which the electricity rate is determined by the sum of a basic fee, which is determined by the peak value of the power supply every 30 minutes, and a metered fee, which is determined by the amount of power used. Patent Document 1 discloses such a power receiving contract. Once the peak value of power is determined, the basic fee based on that peak value continues for one year. The set peak value may be updated to a larger peak value, and if updated, the basic fee based on the updated peak value continues for another year. Once the peak value that serves as the basis for the basic fee is set, the set peak value will not be lowered, no matter how low the peak value is for the following year. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-069678 Summary of the Invention [Problem to be solved by the invention]

[0004] This specification provides a technology for suppressing increases in basic charges in a charging system equipped with a first charger and a second charger under a single contract, which charges a basic charge determined by the peak value of the power supplied and a metered charge according to the amount of power used. [Means for solving the problem]

[0005] The charging system disclosed in this specification includes a first charger, a second charger, and a controller that controls them. The first charger and the second charger belong to a single power receiving contract with an electric power company, under which a base fee determined by the peak value of the power supplied and a metered fee according to the amount of power used are charged. The controller performs the following processing. When it is determined that the first battery will be charged using the first charger, the controller determines a first output pattern of the first charger for charging the first battery based on information about the first battery. When a user requests charging of the second battery after it has been determined that the first battery will be charged using the first charger, the controller determines a second output pattern of the second charger for charging the second battery and a schedule of charging start and end times so that the total output power of the first and second chargers does not exceed a predetermined peak setting value. The controller presents the determined schedule to the user of the second battery. When the controller receives a response from the user agreeing to charging according to the schedule, the controller charges the second battery according to the schedule.

[0006] To prevent the total output power of the first and second chargers from exceeding the peak set value, it may be necessary to delay the start of the second output pattern according to the first output pattern. In other words, the end time of charging the second battery may be delayed. By presenting the charging schedule for the second battery to the user and starting charging of the second battery only after obtaining the user's consent, it is possible to charge the second battery with the user's consent while suppressing increases in the basic charge.

[0007] Details and further improvements of the technology disclosed in this specification are described in the following "Description of Embodiments of the Invention." [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram of a charging system according to an embodiment of the present invention; [Figure 2] 10 is a flowchart of processing by the controller (determining a charging schedule for the first battery). [Figure 3]10 is a flowchart of a process by the controller (determining a charging schedule for the second battery). [Figure 4] 10 is a graph illustrating a second charging schedule determination process. [Figure 5] 10 is a graph illustrating a second charging schedule determination process (modification); DETAILED DESCRIPTION OF THE INVENTION

[0009] A charging system 2 according to an embodiment will be described with reference to the drawings. Fig. 1 shows a block diagram of the charging system 2. The charging system 2 includes a first charger 11, a second charger 12, and a controller 13. These are provided in a charging station 10.

[0010] The first charger 11 and the second charger 12 are devices designed to charge the batteries of electric vehicles and can be connected to charging inlets provided on the electric vehicles. In Fig. 1, the first charger 11 is shown connected to a first electric vehicle 21 to charge a first battery 23 provided on the first electric vehicle 21, and the second charger 12 is shown connected to a second electric vehicle 22 to charge a second battery 24 provided on the second electric vehicle 22.

[0011] The controller 13 controls the first charger 11 and the second charger 12. The controller 13 also receives a charging request from the user of the electric vehicle (battery). The controller 13 obtains information about the battery to be charged (battery type, remaining power) and the amount of charge desired by the user from the user or the user's electric vehicle. The amount of charge desired by the user is expressed as a percentage of a full charge, which is 100%.

[0012] Generally, the power that a battery can accept when charging decreases as the remaining power level increases. This tendency is determined by the battery type. Therefore, once the type of battery to be charged, the remaining power level, and the amount of charge desired by the user are determined, the change over time in the power supplied by the charger to the battery (i.e., the charger output pattern) is determined. When the controller 13 receives a battery charge request from the user, it determines the output pattern of the charger for charging the battery. Once the output pattern is determined, the time required for charging is determined. The controller 13 presents the user with a schedule that includes the start and end times of charging. Specifically, the controller 13 transmits the schedule to the user's information terminal. If the user accepts the schedule, the controller 13 charges the battery according to the schedule.

[0013] The difference between the charging start time and the charging end time corresponds to the required charging time. The schedule may include the charging start time and the required charging time. The charging start time is set to the time desired by the user. However, if the charging start time desired by the user cannot be achieved due to circumstances on the charging station side, the controller 13 presents an alternative charging start time and end time (or required charging time).

[0014] The user of the electric vehicle 21 (22) transmits a battery charging request to the controller 13 using the information terminal 25 (26) provided in the electric vehicle 21 (22). The controller 13 transmits a charging schedule to the information terminal 25 (26). The user uses the information terminal 25 (26) to notify the controller 13 of their acceptance (or rejection) of charging according to the presented schedule. Alternatively, the user may input a charging request using the terminal 14 provided in the charging station 10. In this case, the controller 13 displays the schedule on the terminal 14 and receives, via the terminal 14, the user's response as to whether or not to accept charging according to the schedule.

[0015] Electric power is supplied to charging station 10 (i.e., first charger 11 and second charger 12) by electric power company 30. The operator of charging station 10 and electric power company 30 have concluded an electricity receiving contract under which a base fee determined by the peak value of the supplied power and a metered fee according to the amount of power used are charged. First charger 11 and second charger 12 belong to that single electricity receiving contract. In other words, first charger 11 and second charger 12 are operated under that single electricity receiving contract. In other words, when first charger 11 and second charger 12 are used simultaneously, the peak value of the total power supplied by first charger 11 and second charger 12 becomes the reference peak value when determining the base charge. Hereinafter, the peak value that serves as the calculation basis for the base charge under the electricity receiving contract will be referred to as the peak set value.

[0016] Once a peak setting value is determined, the basic charge based on that peak setting value will continue for one year. After a peak setting value is determined, if the peak value of received power exceeds the peak setting value, the peak setting value will be updated to the larger peak value. Once the peak setting value is updated, the basic charge based on the updated peak setting value will continue for another year. Once a peak setting value is determined, the peak setting value will not be lowered for one year, no matter how low the peak value of received power is. The higher the peak setting value, the higher the basic charge, so a lower peak setting value is better.

[0017] When the electric power company 30 measures the peak value, the electric power company 30 uses, for example, the average (moving average) of the peak values ​​over the most recent predetermined time period (for example, 30 minutes). This is to avoid adopting a spike-like instantaneous peak value as the peak setting value. The peak value may be measured using a method other than the moving average.

[0018] The operator of charging station 10 adjusts the schedule for the second battery so that the basic fee for the electricity receiving contract does not increase, and presents the schedule to the user. The process performed by the controller when charging two batteries (first battery 23 and second battery 24) is described below.

[0019] Now, consider a case in which the user of the first battery 23 (first electric vehicle 21) first transmits a charging request to the charging system 2, and then the user of the second battery 24 (second electric vehicle 22) transmits a charging request to the charging system 2. Figure 2 shows a flowchart of the process for determining a charging schedule for the first battery 23 and presenting it to the user. Figure 3 shows a flowchart of the process for determining a charging schedule for the second battery 24 and presenting it to the user. Note that the symbol "BT" in Figures 2 and 3 means "battery." Figure 4 shows a graph for explaining the charging schedule determination process for the second battery.

[0020] (Processing for charging request from first user) The controller 13 receives a charging request for the first battery 23 from the user (first user) of the first battery 23 (step S12). Here, the charging request is received via the information terminal 25 of the first electric vehicle 21. The charging request includes the desired charging start time and the desired amount of charge. The amount of charge is expressed as a percentage of a full charge taken as 100%.

[0021] Information terminal 25 also serves as a controller for first electric vehicle 21. Controller 13 of charging system 2 accesses information terminal 25 and acquires information about first battery 23 (battery type and current remaining power) (step S13).

[0022] As mentioned above, the power that a battery can receive when charging decreases as the remaining energy level increases. This tendency is determined by the battery type. The controller 13 stores data on charging curves (time curves of the power that a battery can receive when charging) for each battery type, and the controller 13 determines the output pattern (first output pattern) of the first charger 11 for charging the first battery 23 based on the type, remaining energy level, charge level, and the stored charging curve (step S14). Graph G1 in FIG. 4 is an example of the output pattern (first output pattern) of the first charger 11 for charging the first battery 23. In this example, the first user wishes to start charging at time T1. Furthermore, the symbol Pth in FIG. 4 indicates a peak set value. The peak set value Pth is a standard for determining the basic charge for electricity and is determined before the first output pattern is determined.

[0023] The time required for charging (required charging time) is determined from the first output pattern. Furthermore, the charging end time is determined by adding the required charging time to the charging start time desired by the first user. Data on the charging start time and end time (or required charging time) of first battery 23 is referred to as a first charging schedule. In step S14, the first charging schedule is determined together with the first output pattern. Controller 13 presents the first charging schedule to the first user (step S15). Specifically, controller 13 causes information terminal 25 of first electric vehicle 21 to display the first charging schedule.

[0024] If the first user accepts the first charging schedule, the first user connects the first charger 11 to the charging inlet of the first electric vehicle by the charging start time. If the first user accepts the first charging schedule, the controller 13 starts charging the first battery 23 using the first charger 11 when the charging start time arrives (steps S16: YES, S17). At this time, the controller 13 controls the first charger 11 in accordance with the first output pattern (first charging schedule) to charge the first battery 23. On the other hand, if the first user rejects the presented first charging schedule, the controller 13 does nothing and ends the process (step S16: NO). At this time, the first output pattern and the first charging schedule are discarded.

[0025] (Processing for a charging request from a second user) After it has been decided to charge the first battery 23, the user (second user) of the second battery 24 transmits a charging request to the controller 13. The controller 13 accepts the charging request from the second user (step S22). The controller 13 accepts the charging request through the information terminal 26 of the second electric vehicle 22. The charging request includes the desired charging start time and the desired amount of charging.

[0026] Information terminal 26 also serves as a controller for second electric vehicle 22, and controller 13 accesses information terminal 26 to acquire information about second battery 24 (battery type and current remaining energy) (step S23). As in the case of first battery 23, controller 13 determines the output pattern (second output pattern) of second charger 12 for charging second battery 24 from the type, remaining energy, charge amount, and charging curve of second battery 24 (step S24).

[0027] In step S24, the beginning of the second output pattern is set to the charging start time desired by the second user. Graph G2 in Fig. 4 shows the second output pattern. In this example, the charging start time desired by the second user is time T2.

[0028] The controller 13 generates a pattern (combined pattern) by combining the first output pattern and the second output pattern (step S25). Graph G3 in FIG. 4 shows the combined pattern. In this example, at time T2, the sum of the output of the first charger 11 and the output of the second charger 12 exceeds the peak set value Pth by power dP. If the output of the first charger 11 follows graph G1 in FIG. 4 and the output of the second charger 12 follows graph G2, the peak value of the output power will be (Pth + dP) at time T2. Based on the electricity receiving contract, the peak set value Pth is updated to (Pth + dP) at time T2. After time T2, the basic charge of the electricity receiving contract is increased based on the new peak set value (Pth + dP), and this basic charge will be applied for the next year.

[0029] Therefore, the controller 13 changes the second output pattern so that the peak value of the combined pattern does not exceed the peak set value Pth. Specifically, the controller 13 shifts the second output pattern determined in step S24 backward on the time axis (steps S25: YES, S26).

[0030] The controller 13 shifts the second output pattern backward on the time axis until the peak value of the combined pattern no longer exceeds the peak set value Pth. The controller 13 shifts graph G2 in FIG. 4 to graph G4. The white arrow A in FIG. 4 indicates the shift of the second output pattern. At this time, the start time of the second output pattern shifts from time T2 to time T3. The combined pattern of the second output pattern and the first output pattern after the shift is graph G5. The peak value of graph G5 (the point indicated by arrow B in FIG. 4) is below the peak set value Pth. If the outputs of the first charger 11 and the second charger 12 are controlled according to graphs G1 and G4, the peak set value Pth is maintained and the basic charge for the electricity receiving contract is not increased.

[0031] The time from the start time (time T3) to the end time (time T5) of the second output pattern (graph G4) after the shift corresponds to the required charging time for the second battery 24. A schedule (second charging schedule) for charging the second battery 24 is determined from the second output pattern after the shift (step S26). Specifically, the charging start time (time T3) and charging end time (time T5) of the second output pattern after the shift, or the required charging time (time T5 - time T3), corresponds to the second charging schedule.

[0032] The controller 13 presents the second charging schedule determined in step S26 to the second user (step S27). Specifically, the controller 13 causes the information terminal 26 of the second electric vehicle 22 to display the second charging schedule.

[0033] If the second user accepts the second charging schedule, the second user connects the second charger 12 to the charging inlet of the second electric vehicle 22 by the charging start time. If the second user accepts the second charging schedule, when the charging start time arrives, the controller 13 controls the second charger 12 according to the post-shift second output pattern (second charging schedule) to charge the second battery 24 (steps S28: YES, S30). On the other hand, if the second user rejects the presented second charging schedule, the controller 13 does nothing and ends the process (step S28: NO). At this time, the second output pattern and the second charging schedule are discarded.

[0034] If it is determined in step S25 that the peak value of the combined pattern (graph G3) of the first output pattern and the second output pattern does not exceed the peak set value Pth, the peak set value Pth is maintained even if charging of the second battery 24 starts at the charging start time desired by the second user. In this case, the controller 13 accepts the charging request from the second user (step S25: NO, S29). Then, when the charging start time arrives, the controller 13 controls the second charger 12 according to the post-shift second output pattern (second charging schedule) to charge the second battery 24 (step S30).

[0035] Instead of the process of step S29, the controller 13 may execute the following process. That is, the controller 13 may determine a second charging schedule from the second output pattern before the shift, present the second charging schedule to the second user, and proceed to step S30 if the second user accepts the second charging schedule. If the second user does not accept the second charging schedule, the controller 13 discards the second output pattern and the second charging schedule and ends the process.

[0036] (Variation of the second charging schedule determination process) Fig. 5 shows an explanatory diagram of another process for determining a second charging schedule that maintains the peak set value. Graph G1 shows the first output pattern, graph G2 shows the initial second output pattern, and graph G3 shows the combined pattern of the first output pattern and the second output pattern. These graphs G1-G3 are the same as those in Fig. 4.

[0037] The controller 13 removes the portion of the summation pattern (graph G3) that exceeds the peak set value Pth and extends the summation pattern backward on the time axis by the removed area. Graph G6 in FIG. 5 shows the summation pattern (modified summation pattern) after this process. The start point (time T2) and end point (time T6) of the modified summation pattern (graph G6) correspond to the charging start time and end time of the new second charging schedule. The difference between time T6 and time T2 corresponds to the required charging time.

[0038] The controller 13 may perform the process of the above-described modified example instead of the process of step S26 in Fig. 3. The process of the modified example also makes it possible to charge the second battery 24 without increasing the peak setting value and with the second user's consent.

[0039] The processing of step S26 and the processing of the above-described modified example can be summarized as follows: The controller 13 determines a second output pattern for the second charger 12 for charging the second battery 24 so that the total output power of the first charger 11 and the second charger 12 does not exceed the original peak set value Pth, and also determines a schedule of the charging start and end times (second charging schedule) for the second battery 24. This processing makes it possible to charge the second battery 24 without increasing the peak set value and with the second user's consent. Note that in the modified example, the graph obtained by subtracting graph G1 from graph G6 in FIG. 5 corresponds to the second output pattern after adjusting the peak value of the combined pattern.

[0040] A note on the technology described in the embodiment will be given below. In the process of step S26 in FIG. 3, the required charging time is the same as in the case of the initial first output pattern, but the charging start time is later than desired by the user. In the process of the modified example, the charging start time matches the start time desired by the user, but the required charging time is longer. The controller 13 may present both the second charging schedule obtained in the process of step S26 and the second charging schedule obtained in the process of the modified example to the second user, allowing the second user to select the one they prefer.

[0041] The technology disclosed in this specification can also be applied to a charging system having three or more chargers. In that case, the controller 13 determines the output pattern and charging schedule for each of the first and second chargers based on the above process. The controller then simply refers to the combined pattern of the first and second chargers as the "first output pattern" and the third charger as the "second charger," and repeats the above process. If the charging system has four or more chargers, the same process can be repeated.

[0042] As mentioned above, the higher the remaining power of a battery, the lower the power it can accept. This tendency is the same for all types of batteries. The controller may be provided with a map that provides an output pattern when the battery type, remaining power, and desired charge amount are given.

[0043] The terminal through which the user inputs a charging request and which communicates with the controller 13 of the charging system 2 may be an information terminal provided in the electric vehicle, the terminal 14 provided in the charging system 2, or a terminal carried by the user. The chargers 11, 12 and the controller 13 may be located in different locations and connected via a network.

[0044] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives alone is technically useful. [Explanation of symbols]

[0045] 2: Charging system 10: Charging station 11: First charger 12: Second charger 13: Controller 14: Terminal 21, 22: Electric vehicle 23: First battery 24: Second battery 25, 26: Information terminal 30: Power company

Claims

[Claim 1] a first charger and a second charger belonging to a power receiving contract with an electric power company under which a basic fee determined by the peak value of the power supplied and a metered fee according to the amount of power used are charged; a controller that controls the first charger and the second charger; and the controller comprises: determining a first output pattern for charging the first battery of the first charger based on information about the first battery; when a user requests charging of a second battery after it has been determined that the first battery will be charged by the first charger, determining a second output pattern of the second charger for charging the second battery and a schedule of charging start and end times of the second battery so that the total output power of the first charger and the second charger does not exceed a predetermined peak set value; presenting the determined schedule to the user; When a response indicating consent to charging according to the schedule is received, the second battery is charged according to the schedule. Charging system.

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