JP7734862B2 - Electric vehicle charging system, power management device, and electric vehicle charging method - Google Patents

Description

This disclosure relates to an electric vehicle charging system for charging the battery of an electric vehicle, a power management device used therein, and an electric vehicle charging method.

Electric vehicles (EVs) require a large amount of power to charge, placing a heavy load on both the power consumption and peak power. For this reason, efforts are being made to save energy by using regenerative power from railways to charge EVs.

In the electric vehicle charging system disclosed in Patent Document 1, an electric vehicle charging device is connected to a railway feeder line, and regenerative power generated when the train brakes is collected, stored in a power storage device, and used to charge the electric vehicle. This method saves energy because regenerative power that is normally wasted is used to charge the electric vehicle.

JP 2012-080628 A

However, because charging electric vehicles requires high peak power, installing multiple high-capacity chargers to meet the charging demand of multiple electric vehicles requires the installation of high-capacity substation equipment that can handle the peak power required for charging electric vehicles, which poses the issue of increased costs.

For example, the capacity of substation equipment related to railway power feeding facilities is designed to match the peak power required by trains. Therefore, when connecting electric vehicle charging equipment to railway feeder lines, the capacity of the substation equipment must be significantly increased to add electric vehicle charging equipment with high peak power demands, resulting in high costs.

On the other hand, if electric vehicles are charged using only regenerative power when it is being generated, there is no need to increase the capacity of the substation equipment, but the number of electric vehicles that can be charged is reduced because the time periods during which regenerative power is generated and the amount of regenerative power are limited.

This disclosure has been made in consideration of the above and aims to provide an electric vehicle charging system that increases the number of electric vehicles that can be charged without increasing the capacity of the substation equipment.

To solve the above-mentioned problems and achieve the objectives, the electric vehicle charging system disclosed herein comprises a charging station equipped with a charger capable of charging electric vehicles using power supplied from a privately operated line; substation equipment that supplies power to the privately operated line and a feeder line; a power converter installed between the feeder line and the privately operated line and that steps down the power supplied from the feeder line to the privately operated line; and a power management device that manages the power supplied to the charging station by controlling the substation equipment and power converter. The power management device predicts, for each time period, the power used by a train connected to the feeder line when powering, the regenerative power generated when the train brakes, and the available capacity of the substation equipment, and based on the predictions, controls the substation equipment and power converter so that the power supplied to the substation equipment does not exceed a preset rated capacity.

The present disclosure has the effect of providing an electric vehicle charging system that increases the number of electric vehicles that can be charged without increasing the capacity of the substation equipment.

FIG. 1 is a diagram showing a configuration of an electric vehicle charging system according to a first embodiment; FIG. 1 is a diagram illustrating the operation of a power management device and an electric vehicle operation management device in an electric vehicle charging system according to a first embodiment. FIG. 1 is a diagram showing the configuration of a power management device of an electric vehicle charging system according to a first embodiment; FIG. 1 is a diagram showing the configuration of an electric vehicle operation management device according to a first embodiment; FIG. 1 is a diagram showing an example of power generated in an electric vehicle charging system according to the first embodiment. 1 is a flowchart showing the flow of operations of a power management device and an electric vehicle operation management device of an electric vehicle charging system according to a first embodiment. FIG. 10 is a diagram showing the configuration of an electric vehicle charging system according to a second embodiment. FIG. 10 is a diagram showing an example of power generated in an electric vehicle charging system according to a second embodiment. FIG. 10 is a diagram showing the configuration of an electric vehicle charging system according to a third embodiment. FIG. 10 is a diagram showing an example of power generated in an electric vehicle charging system according to a third embodiment. FIG. 1 is a diagram illustrating an example of a hardware configuration of a power management device of an electric vehicle charging system according to any one of first to third embodiments.

Below, the electric vehicle charging system, power management device, and electric vehicle charging method relating to the embodiments are described in detail with reference to the drawings.

Embodiment 1.
Fig. 1 is a diagram showing the configuration of an electric vehicle charging system according to embodiment 1. Fig. 2 is a diagram showing a schematic diagram of the operation of a power management device and an electric vehicle operation management device in the electric vehicle charging system according to embodiment 1. An electric vehicle charging system 300 according to embodiment 1 includes a charging station 6 for charging an electric vehicle 600, a private line 9 laid by an installer of the charging station 6, a main substation 1 connected to the power grid, and a feeding substation 2 and a private line substation 3 connected to the main substation 1.

The electric vehicle charging system 300 also includes a solar power generation facility 7 connected to a private line 9 via a power converter 701, a power converter 8 installed between the feeder line 5 and the private line 9, a power management device 50 that manages the power supplied to the charging station 6, and an electric vehicle operation management device 60 that manages the operation of the electric vehicle 600.

In the electric vehicle charging system 300, the main substation 1, the feeding substation 2, and the private line substation 3 are substation equipment that supplies power to the private line 9 and the feeder 5. The main substation 1 steps down the AC power P1 supplied from the power grid and outputs it. The feeding substation 2 steps down and converts the AC power P2 supplied from the main substation 1 into DC, and supplies it to the feeder 5 for supplying power to the train 4. The private line substation 3 steps down the AC power P3 supplied from the main substation 1 and supplies it to the private line 9. In the electric vehicle charging system 300 relating to embodiment 1, the current flowing through the private line 9 is AC.

The power P1 supplied to the main substation 1 is the sum of the power P2 supplied to the feeding substation 2 and the power P3 supplied to the private line substation 3.

The charging station 6 includes a charger 601 for charging the electric vehicle 600, a storage battery 602 for storing power, a power converter 604 for reducing the voltage of the power charging the storage battery 602 and for increasing the voltage of the power discharged from the storage battery 602, and a power converter 603 for converting the power supplied from the private line 9 to DC and reducing the voltage.

The power management device 50 communicates with the charger 601, power converter 603, and power converter 604, and charges the electric vehicle 600, charges and discharges the storage battery 602, and supplies power from the private line 9 to the charging station 6. The electric vehicle operation management device 60 communicates with each of the multiple electric vehicles 600 and instructs them to operate based on a preset operation schedule.

The feeding substation 2 comprises a transformer 201 and a rectifier 202. The power P2 supplied to the feeding substation 2 is stepped down by the transformer 201, and then converted to DC power by the rectifier 202, which is then supplied to the feeder line 5 as DC power. The train 4 exchanges DC power with the feeder line 5.

With regard to the power P4 exchanged between the feeder 5 and the train 4, the power supplied from the feeder 5 to the train 4 is defined as positive power, and the power supplied from the train 4 to the feeder 5 is defined as negative power. When the train 4 is powered, the train 4 receives power P4 from the feeder 5, so power P4 is positive. On the other hand, when the train 4 brakes, regenerative power obtained by converting kinetic energy into electrical energy is supplied from the train 4 to the feeder 5, so power P4 is negative.

The power converter 8 converts the power supplied from the feeder 5 to the private line 9 into AC power and boosts its voltage. When regenerative power generated by the train 4 is recovered by the feeder 5, power P5 is supplied from the feeder 5 to the private line 9 via the power converter 8. The solar power generation facility 7 generates solar power. The power converter 701 converts the power obtained by solar power generation in the solar power generation facility 7 into AC power and boosts its voltage, and supplies the solar-generated power P7 to the private line 9. Therefore, the private line 9 is supplied with power P3 obtained by stepping down the voltage of power P3 in the private line substation 3, power P5 supplied from the feeder 5 through the power converter 8 by the feeder 5 recovering regenerative power, and solar-generated power P7 obtained by boosting the power generated by solar power generation in the solar power generation facility 7.

The charging station 6 is supplied with power P6 from the private line 9 via a power converter 603. The power P6 supplied to the charging station 6 is the sum of power P3 stepped down in the private line substation 3, solar-generated power P7, and regenerated power P5.

Figure 3 is a diagram showing the configuration of a power management device for an electric vehicle charging system according to embodiment 1. The power management device 50 includes a control unit 51 that controls the charger 601, the storage battery 602, the power converter 603, the power converter 604, the power converter 8, the feeding substation 2, and the private line substation 3, and a processing unit 52 that creates a maximum charging power table that indicates the maximum power that can be supplied to the charger 601 by controlling the charging and discharging of the storage battery 602 for each time period, and a charging fee table that indicates the charging fee for the electric vehicle 600 for each time period. The processing unit 52 includes a solar power generation amount prediction unit 521 that predicts the amount of solar power generation power P7, a regenerative power amount prediction unit 522 that predicts the amount of regenerative power, a substation available capacity prediction unit 523 that predicts the available capacity of the main substation 1, and a table creation unit 524 that creates the maximum charging power table and the charging fee table.

Figure 4 is a diagram showing the configuration of an electric vehicle operation management device according to embodiment 1. The electric vehicle operation management device 60 includes a control unit 61 that dispatches electric vehicles 600, and a processing unit 62 that creates a charging plan for the electric vehicles 600. The processing unit 62 includes a charging demand prediction unit 621 that predicts the charging demand for the electric vehicles 600, and a charging plan creation unit 622 that creates a charging plan for the electric vehicles 600.

Figure 5 is a diagram showing an example of power generated in the electric vehicle charging system according to embodiment 1. In Figure 5, the vertical axis represents power and the horizontal axis represents time. Time period T1 is a time period when train 4 is stopped, and the power P2 supplied to the feeding substation 2 is small. Time period T2 is a time period when train 4 is powering, and the power P2 supplied to the feeding substation 2 is large. Time period T3 is a time period when train 4 is coasting, and the power P2 supplied to the feeding substation 2 is small. Time period T4 is a time period when train 4 is braking, and regenerative power is being supplied from train 4 to feeder line 5, so the power P4 exchanged between train 4 and feeder line 5 is negative.

By controlling the charger 601, the storage battery 602, the power converter 603, the power converter 604, the power converter 8, and the power converter 701, the power management device 50 supplies power P3 to the private line substation 3 without restriction during time periods T1 and T3 when the power P2 supplied to the feeding substation 2 is low, and suppresses the power P3 supplied to the private line substation 3 during time period T2 when the power P2 received by the feeding substation 2 is high.

The power P2 supplied to the power feeding substation 2 peaks during time period T2 when the train 4 is powered. Meanwhile, during time period T2 when the power P2 supplied to the power feeding substation 2 is high, the power management device 50 suppresses the power P3 supplied to the private line substation 3. Therefore, the peak of power P3 occurs during time period T1 or T3 when the power P2 supplied to the power feeding substation 2 is low. By shifting the peaks of power P2 and P3 in this way, even if the sum of the peak power value of power P2 supplied to the power feeding substation 2 and the peak power value of power P3 supplied to the private line substation 3 exceeds the rated capacity Pn1 of the main substation 1, the power P1 supplied to the main substation 1 can be kept below the rated capacity Pn1. This allows the number of electric vehicles 600 that can be charged to be increased without upgrading the main substation 1 to increase its rated capacity.

Next, the operation of the power management device 50 and electric vehicle traffic management device 60, which realize the control described above, will be described. FIG. 6 is a flowchart showing the operation flow of the power management device and electric vehicle traffic management device of the electric vehicle charging system according to embodiment 1. In step S1, the solar power generation amount prediction unit 521 predicts the amount of power generated by the solar power generation facility 7 based on a weather forecast. Next, in step S2, the regenerative power amount prediction unit 522 predicts the amount of power used by the train 4, the amount of regenerative power generated, and the time period during which the regenerative power will be generated based on railway operation information. The railway operation information includes predicted data on the train 4's schedule and number of passengers. For example, the regenerative power amount prediction unit 522 predicts the amount of power used by the train 4 and the time period during which the train 4 will use power by estimating the time period during which the train 4 will brake based on the railway operation information. Furthermore, the regenerative power amount prediction unit 522 predicts the amount of regenerative power generated and the time period during which the regenerative power will be generated by estimating the time period during which the train 4 will brake based on the railway operation information. Furthermore, the substation available capacity prediction unit 523 predicts the available capacity of the main substation 1. For example, the substation available capacity prediction unit 523 estimates the time period during which the train 4 will be powered based on railway operation information, and predicts the power P2 supplied to the feeding substation 2, the power P3 supplied to the private line substation 3, and the power P1 supplied to the main substation 1, which is the sum of the power P2 and the power P3. The substation available capacity prediction unit 523 estimates the available capacity relative to the rated capacity Pn1 of the main substation 1, based on the power P1 supplied to the main substation 1, the power P2 supplied to the feeding substation 2, and the power P3 supplied to the private line substation 3.

In step S3, the table creation unit 524 creates a maximum charging power table and a charging fee table. As described above, the power P3 that can be supplied by the private line substation 3 is restricted for each time period depending on the power P2 supplied to the feeding substation 2. Therefore, the maximum power that can be supplied to the charging station 6 varies for each time period depending on the power P2 supplied to the feeding substation 2, the solar-generated power P7 supplied from the solar power generation equipment 7, and the power P5 resulting from regenerative power supplied from the train 4. The table creation unit 524 creates a maximum charging power table as a table for each time period for the maximum power that can be supplied to the charger 601 by charge/discharge control of the storage battery 602 installed in the charging station 6, based on the power P2 supplied to the feeding substation 2, the solar-generated power P7 supplied from the solar power generation equipment 7, and the power P5 resulting from regenerative power supplied from the train 4.

The charging fee table is created based on the maximum charging power table, the predicted value of solar-generated power P7, and the predicted value of regenerated power. To maximize the use of solar-generated power P7 and regenerated power P5 for charging the electric vehicle 600, charging fees are set low during time periods when solar-generated power P7 and regenerated power are abundant. Furthermore, during time periods when the train 4 is powering and the power P2 supplied to the feeding substation 2 is high, the available capacity of the main substation 1 is low and the maximum charging power is low. To avoid a concentration of charging demand during such time periods when the maximum charging power is low, charging fees are set high. In this way, the table creation unit 524 optimizes the charging plan for the electric vehicle 600 by setting different variable charging fees for each time period based on the maximum charging power based on the available capacity of the main substation 1, the solar-generated power P7, and the predicted value of regenerated power.

In step S4, the control unit 51 transmits the maximum charging power table and charging fee table created by the table creation unit 524 to the electric vehicle operation management device 60.

Meanwhile, in the electric vehicle operation management device 60, in step S11, the charging demand prediction unit 621 predicts the charging demand for the electric vehicle 600 based on the electric vehicle operation information. For example, if the electric vehicle 600 is a bus, the electric vehicle operation information includes predicted data on the bus schedule and the number of bus passengers. Also, for example, if the electric vehicle 600 is a taxi, the electric vehicle operation information includes predicted data on the number of taxi passengers and the distance traveled. Also, for example, if the electric vehicle 600 is a private car, the electric vehicle operation information includes predicted data on traffic information indicating the degree of road congestion.

In step S12, the control unit 61 of the electric vehicle operation management device 60 receives the maximum charging power table and charging fee table transmitted from the power management device 50. In step S13, the charging plan creation unit 622 creates a charging plan for the electric vehicle 600 whose operation it manages based on the maximum charging power table and the charging fee table. For example, the charging plan creation unit 622 creates a charging plan such that charging of the electric vehicle 600 is given priority during time periods when the charging fee for the electric vehicle 600 is set low. In step S14, the control unit 61 transmits the charging plan created by the charging plan creation unit 622 to the power management device 50.

In step S5, the control unit 51 of the power management device 50 receives the charging plan transmitted from the electric vehicle operation management device 60. The power management device 50 displays the charging plan received from the electric vehicle operation management device 60 on a display unit (not shown) or makes it public via the Internet, allowing users of electric vehicles 600 whose operation is not managed by the electric vehicle operation management device 60 to know in advance the degree of congestion at the charging station 6.

This completes the operation of the power management device 50 and electric vehicle operation management device 60 before business hours begin.

The above operations are repeatedly performed at preset time intervals even after business hours have begun. For example, the system is operated while making successive adjustments in response to at least one of changes in the weather forecast, delays in train or bus schedules, and updates to electric vehicle operation information. By operating in this manner, the electric vehicle charging system 300 according to embodiment 1 can increase the number of electric vehicles 600 that can be charged without increasing the capacity of the main substation equipment 1.

The electric vehicle charging system 300 of embodiment 1 predicts the power consumption of the train 4 connected to the feeder line 5 when powering, the regenerative power generated when the train 4 brakes, and the available capacity of the main substation 1 for each time period, and based on the predictions, controls the feeding substation 2 and the power converter 8 so that the power supplied to the main substation 1 does not exceed a preset rated capacity.Therefore, the number of electric vehicles 600 that can be charged can be increased without having to perform equipment updates that increase the rated capacity of the main substation 1.

Embodiment 2.
7 is a diagram showing the configuration of an electric vehicle charging system according to embodiment 2. Only the parts that differ from electric vehicle charging system 300 according to embodiment 1 will be described, and a description of the parts that are common will be omitted.

In the electric vehicle charging system 300 according to the second embodiment, the current flowing through the private power line 9 is direct current. In the electric vehicle charging system 300 according to the second embodiment, the power feeding substation 2 steps down and converts power P2 supplied from the main power substation 1 to direct current, and supplies the direct current power to the feeder line 5. A power converter 8 is installed between the feeder line 5 and the private power line 9. Power is supplied to the private power line 9 from the power feeding substation 2 via the power converter 8. When regenerative power generated during braking of the train 4 is recovered by the feeder line 5, the regenerative power is stepped down by the power converter 8 and power P5 is supplied to the private power line 9. The power converter 603 steps down the power supplied from the private power line 9. The power converter 701 boosts the power generated by solar power generation in the solar power generation facility 7, and supplies the solar-generated power P7 to the private power line 9.

Figure 8 is a diagram showing an example of power generated in an electric vehicle charging system according to embodiment 2. In Figure 8, the vertical axis represents power and the horizontal axis represents time. Power P2 is power supplied to the feeding substation 2 from the main substation 1. Power P4 is power exchanged between the train 4 and the feeder line 5. Power P5 is power supplied from the feeder line 5 to the private line 9 via the power converter 8.

As in embodiment 1, with regard to the power P4 exchanged between the feeder 5 and the train 4, the power supplied from the feeder 5 to the train 4 is defined as positive power, and the power supplied from the train 4 to the feeder 5 is defined as negative power.

Time period T1 is a time period when train 4 is stopped, and the positive power P4 supplied to train 4 from feeder 5 is small. Time period T2 is a time period when train 4 is powered, and the positive power P4 supplied to train 4 from feeder 5 is large. Time period T3 is a time period when train 4 is coasting, and the positive power P4 supplied to train 4 from feeder 5 is small. Time period T4 is a time period when train 4 is braking, and negative power is supplied from train 4 to feeder 5.

By controlling the charger 601, the storage battery 602, the power converter 603, the power converter 604, and the power converter 8, the power converter 8 supplies power P5 from the feeder 5 to the private line 9 during time periods T1 and T3 when the positive power supplied from the feeder 5 to the train 4 is low, and during time period T4 when negative power is supplied from the train 4 to the feeder 5, and controls the power converter 8 to suppress the power P5 supplied from the feeder 5 to the private line 9 during time period T2 when the positive power supplied from the feeder 5 to the train 4 is high. Therefore, when the train 4 brakes, power is supplied from the train 4 to the charging station 6, when the train 4 is stopped, power is supplied from the feeding substation 2 to the charging station 6, and when the train 4 is powered, the supply of power from the feeder 5 to the charging station 6 is stopped.

During time period T2 when the positive power supplied to the train 4 from the feeder line 5 is large, the power management device 50 suppresses the power P5 supplied from the feeder line 5 to the private line 9. This allows the power P2 supplied from the main substation 1 to the feeding substation 2 to be kept at or below the rated capacity Pn2, while a large amount of power P6 exceeding the rated capacity Pn2 can be supplied to the charging station 6 via the private line 9. This makes it possible to increase the number of electric vehicles 600 that can be charged without having to perform equipment upgrades that increase the rated capacity of the main substation 1 and the feeding substation 2.

The operational flow of the electric vehicle charging system 300 according to the second embodiment is the same as that of the electric vehicle charging system 300 according to the first embodiment shown in FIG. 6 , except that in step S2, the substation available capacity prediction unit 523 calculates the available capacity of the feeding substation 2, rather than the available capacity of the main substation 1. In addition, in step S3, the table creation unit 524 creates a charging rate table by setting a high charging fee for a time period when the available capacity of the feeding substation 2 is low and the maximum charging power is low because the train 4 is powering and the power P2 supplied to the feeding substation 2 is large, in order to avoid a concentration of charging demand during that time period. In this way, by setting a variable charging fee that differs for each time period based on the maximum charging power based on the available capacity of the feeding substation 2, the solar-generated power P7, and the predicted value of regenerative power, the charging plan for the electric vehicle 600 is optimized.

The electric vehicle charging system 300 of embodiment 2 predicts the power consumption of the train 4 connected to the feeder line 5 when powering, the regenerative power generated when the train 4 brakes, and the available capacity of the feeding substation 2 for each time period, and based on the predictions, controls the power converter 8 so that the power supplied to the feeding substation 2 does not exceed a preset rated capacity.Therefore, the number of electric vehicles 600 that can be charged can be increased without having to perform equipment updates that increase the rated capacity of the feeding substation 2.

Embodiment 3.
9 is a diagram showing the configuration of an electric vehicle charging system according to embodiment 3. Only the parts that differ from electric vehicle charging system 300 according to embodiment 2 will be described, and a description of the parts that are common will be omitted.

As with the electric vehicle charging system 300 according to embodiment 2, in the electric vehicle charging system 300 according to embodiment 3, the current flowing through the private line 9 is direct current. In the electric vehicle charging system 300 according to embodiment 3, the feeding substation 2 includes a power converter 203 that steps down the direct current power output from the rectifier 202. The feeding substation 2 supplies the private line 9 with direct current power stepped down by the transformer 201, and supplies the feeder line 5 with direct current power stepped down by the power converter 203. When regenerative power generated during braking of the train 4 is recovered by the feeder line 5, the regenerative power is boosted by the power converter 8, and power P5 is supplied from the feeder line 5 to the private line 9. The solar power generation facility 7 is installed within the charging station 6.

Figure 10 is a diagram showing an example of power generated in an electric vehicle charging system according to embodiment 3. In Figure 10, the vertical axis represents power and the horizontal axis represents time. Power P2 is power supplied to the feeding substation 2. Power P4 is power exchanged between the train 4 and the feeder line 5. Power P6 is power supplied to the charging station 6.

Time period T1 is a time period when train 4 is stopped, and the positive power P4 supplied to train 4 from feeder 5 is small. Time period T2 is a time period when train 4 is powered, and the positive power P4 supplied to train 4 from feeder 5 is large. Time period T3 is a time period when train 4 is coasting, and the positive power P4 supplied to train 4 from feeder 5 is small. Time period T4 is a time period when train 4 is braking, and negative power is supplied from train 4 to feeder 5.

By controlling the charger 601, the storage battery 602, the power converter 603, the power converter 604, the power converter 8, and the power converter 203, the power management device 50 supplies power P6 from the private line 9 to the charging station 6 during time periods T1 and T3 when the positive power supplied from the feeder 5 to the train 4 is low, and during time period T4 when negative power is supplied from the train 4 to the feeder 5, and controls to suppress the supply of power P6 from the private line 9 to the charging station 6 during time period T2 when the positive power supplied from the feeder 5 to the train 4 is high. In other words, during time periods T1, T3, and T4, the power management device 50 supplies power from the feeder 5 to the private line 9 via the power converter 8, and supplies power from the private line 9 to the charging station 6 via the power converter 603. On the other hand, during time period T2, the power management device 50 suppresses at least one of the supply of power P5 from the feeder line 5 to the private line 9 via the power converter 8 and the supply of power P6 from the private line 9 via the power converter 603.

During time period T2 when the positive power supplied to the train 4 from the feeder line 5 is large, the power management device 50 suppresses the power P6 supplied from the private line 9 to the charging station 6. This makes it possible to keep the power P2 supplied from the main substation 1 to the feeding substation 2 at or below the rated capacity Pn2, while supplying a large amount of power P6 exceeding the rated capacity Pn2 to the charging station 6 via the private line 9. This makes it possible to increase the number of electric vehicles 600 that can be charged without having to perform equipment upgrades that increase the rated capacity of the main substation 1 and the feeding substation 2.

The operational flow of the electric vehicle charging system 300 according to the third embodiment is the same as that of the electric vehicle charging system 300 according to the first embodiment shown in FIG. 6 , except that in step S2, the substation available capacity prediction unit 523 calculates the available capacity of the feeding substation 2, rather than the available capacity of the main substation 1. Furthermore, in step S3, during a time period when the train 4 is powering and the power P2 supplied to the feeding substation 2 is large, the available capacity of the feeding substation 2 is small, and the maximum charging power is low, a high charging fee is set to avoid a concentration of charging demand during that time period. In this way, by setting a variable charging fee that differs for each time period based on the maximum charging power based on the available capacity of the feeding substation 2, the solar-generated power P7, and the predicted value of regenerative power, the charging plan for the electric vehicle 600 is optimized.

The electric vehicle charging system 300 of embodiment 3 predicts the power consumption of the train 4 connected to the feeder line 5 when powering, the regenerative power generated when the train 4 brakes, and the available capacity of the feeding substation 2 for each time period, and controls the power converter 603 based on the prediction so that the power supplied to the feeding substation 2 does not exceed a preset rated capacity.Therefore, the number of electric vehicles 600 that can be charged can be increased without having to perform equipment updates that increase the rated capacity of the feeding substation 2.

Next, the hardware configuration of the power management device 50 and electric vehicle operation management device 60 that make up the electric vehicle charging system 300 will be described. Figure 11 is a diagram showing an example of the hardware configuration of a power management device of an electric vehicle charging system relating to any of embodiments 1 to 3. As shown in Figure 11, the power management device 50 is a computer system comprising a processor 101, memory 102, storage device 103, and interface circuit 104. The processor 101, memory 102, storage device 103, and interface circuit 104 can send and receive data to and from each other via a bus 105.

The processor 101 executes the functions of the control unit 51 and processing unit 52 by reading and executing the operating system (OS) and processing programs stored in the storage device 103. Note that part or all of the control unit 51 and processing unit 52 may also be configured using hardware such as an ASIC (Application Specific Integrated Circuit) and an FPGA (Field Programmable Gate Array). In other words, the processing circuitry that realizes part or all of the control unit 51 and processing unit 52 may be dedicated hardware.

In addition, the processor 101 can read the OS and processing program from one or more storage media including a magnetic disk, a USB (Universal Serial Bus) memory, an optical disk, a compact disk, and a DVD (Digital Versatile Disc) via an interface not shown, store them in the storage device 103, and execute them.

The power management device 50 may also be realized by multiple information processing devices connected to each other. When the power management device 50 includes multiple information processing devices, the processing executed by the power management device 50 can be virtually regarded as a single information processing device by each of the multiple information processing devices executing the processing.

The electric vehicle operation management device 60 is also a computer system comprising a processor 101, memory 102, storage device 103, and interface circuit 104. The processor 101 performs the functions of the control unit 61 and processing unit 62 by reading and executing the OS and processing programs stored in the storage device 103. Note that part or all of the control unit 61 and processing unit 62 can also be configured using hardware such as ASICs and FPGAs. In other words, the processing circuits that realize part or all of the control unit 61 and processing unit 62 may be dedicated hardware.

The configurations shown in the above embodiments are merely examples of the content, and may be combined with other known technologies, or parts of the configuration may be omitted or modified without departing from the spirit of the invention.

1 Main substation, 2 Feeder substation, 3 Private line substation, 4 Train, 5 Feeder, 6 Charging station, 7 Solar power generation equipment, 8, 203, 603, 604, 701 Power converter, 9 Private line, 50 Power management device, 51, 61 Control unit, 52, 62 Processing unit, 60 Electric vehicle operation management device, 101 Processor, 102 Memory, 103 Storage device, 104 Interface circuit, 105 Bus, 201 Transformer, 202 Rectifier, 300 Electric vehicle charging system, 521 Solar power generation amount prediction unit, 522 Regenerative power amount prediction unit, 523 Substation equipment available capacity prediction unit, 524 Table creation unit, 600 Electric vehicle, 601 Charger, 602 Storage battery, 621 Charging demand prediction unit, 622 Charging plan creation unit.

Claims (12)

a charging station equipped with a charger capable of charging an electric vehicle using power supplied from a private line;
a substation facility for supplying power to the private power lines and the feeder lines;
a power converter installed between the feeder line and the private line, which reduces the voltage of power supplied from the feeder line to the private line;
a power management device that manages power supplied to the charging station by controlling the substation and the power converter,
the power management device predicts, for each time period, the power used by the train connected to the feeder line when it is powered, the regenerative power generated when the train is braking, and the available capacity of the substation equipment;
An electric vehicle charging system characterized by controlling the substation and the power converter based on the prediction so that the power supplied to the substation does not exceed a preset rated capacity. The electric vehicle charging system of claim 1, characterized in that the power management device supplies power from the feeder to the private line and from the private line to the charging station when the train connected to the feeder is stopped, coasting, or braking, and suppresses at least one of the power supply from the feeder to the private line and the power supply from the private line to the charging station when the train is powering. The electric vehicle charging system of claim 1 or 2, characterized in that the substation equipment includes a main substation that steps down and outputs the power supplied from the power grid, and a power supply substation that steps down and converts the power supplied from the main substation to DC. Equipped with a solar power generation facility that generates solar power,
The solar power generation facility is connected to the private line,
4. The electric vehicle charging system according to claim 3, wherein the power management device reduces the power supplied from the feeding substation to the feeder line by an amount corresponding to the solar-generated power and the regenerated power during the time periods when the solar-generated power is supplied to the private line and the time periods when the regenerated power is generated. The electric vehicle charging system described in claim 4, characterized in that the power management device predicts the time period in which the regenerative power will be generated and the amount of the regenerative power based on the train operation information, and changes the amount of power supplied from the main substation to the feeding substation when the train brakes for each time period based on the prediction results. a private line substation that supplies the power supplied from the main substation to a private line connected to the charging station;
4. The electric vehicle charging system according to claim 3, wherein the power management device changes the power supplied from the main substation to the private line substation when the train is powering and when the train is stopped, coasting, or braking, so that the sum of the power supplied from the main substation to the feeding substation and the power supplied from the main substation to the private line substation is equal to or less than the rated capacity of the main substation. Equipped with a solar power generation facility that generates solar power,
The solar power generation facility is connected to the private line,
7. The electric vehicle charging system of claim 6, wherein the power management device reduces the power supplied from the private line substation to the private line by the amount of the solar-generated power and the regenerated power during the time periods when the solar-generated power is supplied to the private line and the time periods when the regenerated power is generated. The electric vehicle charging system described in claim 7, characterized in that the power management device predicts the time period in which the regenerative power will be generated and the amount of the regenerative power based on the train operation information, and changes the amount of power supplied from the main substation to the private line substation during braking of the train for each time period based on the prediction results. an electric vehicle operation management device that manages the operation schedule of the electric vehicle;
the power management device transmits a charging fee table created by setting a charging fee for the electric vehicle for each time period according to the amount of generated regenerative power to the electric vehicle operation management device;
5. The electric vehicle charging system according to claim 4 , wherein the electric vehicle operation management device determines a time period during which the electric vehicle is to be charged based on the charging fee table. The electric vehicle charging system of claim 9, wherein the power management device creates the charging fee table by setting lower charging fees for the electric vehicle during time periods when the amount of regenerated power is greater and when the amount of solar-generated power is greater. In an electric vehicle charging system including a charging station equipped with a charger capable of charging an electric vehicle using power supplied from a private line, a substation that supplies power to the private line and a feeder line, and a power converter that is installed between the feeder line and the private line and that reduces the voltage of the power supplied from the feeder line to the private line, a power management device that manages power supplied to the charging station by controlling the substation equipment and the power converter,
A power management device characterized by predicting the power usage of a train connected to the feeder line when powering, the regenerative power generated when the train brakes, and the available capacity of the substation equipment for each time period, and controlling the substation equipment and the power converter based on the predictions so that the power supplied to the substation equipment does not exceed a preset rated capacity. An electric vehicle charging method using an electric vehicle charging system including: a charging station equipped with a charger for charging an electric vehicle using power supplied from a private line; a substation that supplies power to the private line and a feeder; a power converter that is installed between the feeder and the private line and that steps down the power supplied from the feeder to the private line; and a power management device that manages power supplied to the charging station by controlling the substation and the power converter,
the power management device predicts, for each time period, the power consumption used by the train connected to the feeder line when the train is powered, the regenerative power generated when the train is braking, and the available capacity of the substation equipment;
and controlling the substation and the power converter based on the prediction so that the power supplied to the substation does not exceed a preset rated capacity.