Charging device

Abstract

The invention provides a charging device. This charging device is provided with: a plurality of power output devices; and a charging control device that, on the basis of a control command from the vehicle, charges the vehicle-mounted power storage device using at least some of the plurality of power output devices. The charging control device sets a power output device for charging the power storage device on the basis of thermal damage of the plurality of power output devices. As a result, it is possible to select a more appropriate power output device from among the plurality of power output devices and charge the in-vehicle power storage device.

Description

Technical Field

[0001] The present disclosure relates to a charging device. Specifically, the present disclosure relates to a charging device including a charging control device that charges a power storage device mounted on a vehicle using at least some of a plurality of power output devices based on a control instruction from the vehicle. Background Art

[0002] Conventionally, as such a charging device, a charging device that charges a secondary battery with two chargers connected in parallel that output power according to an input power command value has been proposed (for example, refer to Japanese Unexamined Patent Application Publication No. 2019-103264). When a total power command value for controlling the total output power from the two chargers is equal to or less than the maximum possible output value of a first charger among the two chargers, the charging device allocates the total power command value to the first charger. When the total power command value exceeds the maximum possible output value of the first charger, the charging device allocates a specified power value, for which the power conversion efficiency in a second charger among the two chargers is equal to or more than a specified value, to the second charger. According to an allocation map in which a remaining power value obtained by subtracting the specified power value from the total power command value is allocated to the first charger until it exceeds the maximum possible output value, the charging device allocates the total power command value to the two chargers. As a result, even when the charger has a region with low power conversion efficiency, it is possible to output a target total power. Summary of the Invention

[0003] However, in the above charging device, it is sometimes impossible to ensure a desired charging power due to damage to the charger caused by heat generation. When heat is generated, the higher the temperature, the lower the output power of the charger. Therefore, when charging the secondary battery using a charger with an increased temperature, it may not be possible to charge the secondary battery with the rated maximum output power of the charger. Therefore, even when charging the secondary battery using a plurality of chargers, it is necessary to control the chargers in consideration of thermal damage (output power) of each charger.

[0004] A main object of the charging device of the present disclosure is to select a more appropriate power output device from a plurality of power output devices and charge a power storage device mounted on a vehicle.

[0005] The charging device of the present disclosure employs the following means to achieve the above main object.

[0006] The charging device of the present disclosure includes a plurality of power output devices and a charging control device that charges a power storage device mounted on a vehicle using at least some of the plurality of power output devices based on a control instruction from the vehicle, and is characterized in that

[0007] The charging control device sets the power output devices for charging the energy storage device based on the thermal damage of each power output device.

[0008] The charging device of the present disclosure includes: a plurality of power output devices; and a charging control device that, based on a control instruction from a vehicle, uses at least some of the plurality of power output devices to charge an in-vehicle energy storage device. The charging control device sets the power output devices for charging the energy storage device based on the thermal damage of each power output device. Thus, a more appropriate power output device can be selected from the plurality of power output devices to charge the in-vehicle energy storage device.

[0009] In the charging device of the present disclosure,

[0010] The charging control device determines the priority order of the plurality of power output devices in ascending order of the thermal damage, and sets the power output devices in the priority order as the power output devices for charging the energy storage device.

[0011] In this way, the device with less thermal damage among the plurality of power output devices can be preferentially set as the power output device for charging the energy storage device.

[0012] In this case, the control instruction is a charging power instruction, and the charging control device may also set the power output devices before the position where the cumulative value exceeds the charging power instruction when cumulatively adding the available output power of the power output devices in the order of the priority order as the power output devices for charging the energy storage device.

[0013] In this way, the energy storage device can be charged more appropriately based on the charging power instruction.

[0014] In addition, the charging control device may also determine that the smaller the thermal damage is when the available output power of the power output device is larger.

[0015] This is because the larger the thermal damage is, the smaller the available output power of the power output device is.

[0016] In addition, the charging control device may also reduce the priority order of the power output device used in the previous charging of the energy storage device.

[0017] In this way, the usage frequency of a specific power output device can be reduced, and the plurality of power output devices can be used for charging the energy storage device more evenly. Description of the Drawings

[0018] The features, advantages, and technical and industrial significance of the exemplary embodiments of the present invention will be described below with reference to the drawings, in which the same reference numerals represent the same elements, and wherein:

[0019] Figure 1 is a schematic configuration diagram showing the configuration of a charging device 20 representing an embodiment of the present invention;

[0020] Figure 2 is a schematic configuration diagram showing the configuration of an electric vehicle 120 that can utilize the charging device 20;

[0021] Figure 3 is a flowchart showing an example of a charging process mainly executed by a charging ECU 30;

[0022] Figure 4 is a flowchart showing an example of a priority setting process executed by the charging ECU 30;

[0023] Figure 5 is a list showing an example of the output power and priority order of power units 24(1) to 24(8);

[0024] Figure 6 is a flowchart showing an example of a priority setting process of a modified example. Detailed Embodiment

[0025] Next, a mode (embodiment) for implementing the present disclosure will be described. Figure 1 is a schematic structural diagram showing the structure of a charging device 20 as an embodiment of the present invention. The charging device 20 of the embodiment is configured as a charging station, as Figure 1 shown, and includes a power unit device 22 and a charging electronic control unit (hereinafter referred to as "charging ECU") 30.

[0026] The power unit device 22 is connected to a power line 12 from external power 10 and to a charging line 26 of a charging connector 28, and the charging connector 28 is connected to a connector 139 (insertion port) of the electric vehicle 120. The power unit device 22 charges a storage battery 124 mounted on the electric vehicle 120 using the power from the external power 10. A plurality of power units 24(1) to 24(n) that function as power output devices are connected in parallel to the power unit device 22. Each of the power units 24(1) to 24(n) is composed of the same unit such as an AC / DC converter that converts AC power from the external power 10 into DC power and a DC / DC converter that converts the voltage of the DC power.

[0027] The charging ECU 30 is configured as a microcomputer centered around a CPU. The charging ECU 30 receives the temperatures T(1) to T(n) of each power unit 24(1) to 24(n) from the power unit device 22. Based on the temperatures T(1) to T(n) of each power unit 24(1) to 24(n), the charging ECU 30 sets the outputtable electric powers P(1) to P(n) of each power unit 24(1) to 24(n). The outputtable electric power P is set such that the higher the temperature T of the power unit, the smaller it is due to thermal damage, and is set to the rated value at normal temperature. The charging ECU 30 is connected to the electronic control unit 130 of the electric vehicle 120 via the communication line 32 and communicates with the vehicle side.

[0028] As a vehicle that can use the charging device 20 of the embodiment, for example, Figure 2 the illustrated electric vehicle 120 can be cited. The electric vehicle 120 includes a motor 122, an inverter 123, a storage battery 124, a charge / discharge circuit 138, a connector 139, and an electronic control unit 130.

[0029] The motor 122 is configured as a synchronous generator motor, for example. The rotor of the motor 122 is connected to the drive shaft 125 linked to the drive wheels 128a and 128b via a differential gear 126. The motor 122 is driven by converting the direct current from the battery 124 into three-phase alternating current using the inverter 123 and applying the three-phase alternating current using the inverter 123. In addition, the battery 124 is configured as a known lithium-ion secondary battery or nickel-metal hydride secondary battery.

[0030] One end of the charge / discharge circuit 138 is connected to the power line connected to the storage battery 124, and the other end is connected to the connector 139 for connecting to the charging connector 28 of the charging device 20. The charge / discharge circuit 138 has a charge / discharge relay (not shown) and can connect to and disconnect from the storage battery 124 through the charge / discharge relay.

[0031] Although not shown, the electronic control unit 130 is configured as a microcomputer centered around a CPU. The electronic control unit 130 inputs signals from various sensors via an input port. For example, the electronic control unit 130 inputs an ignition signal from the ignition switch 142, a shift position SP from the shift position sensor 144 that detects the gear position of the shift lever 143, an accelerator opening Acc from the accelerator pedal depression position sensor 146 that detects the depression amount of the accelerator pedal 145, a brake depression position BP from the brake pedal depression position sensor 148 that detects the depression amount of the brake pedal 147, a vehicle speed V from the vehicle speed sensor 149, etc. In addition, the electronic control unit 130 also inputs a rotational position θ from a rotational position sensor (not shown) that detects the rotational position of the motor 122, a battery voltage Vb from a voltage sensor (not shown) installed at the output terminal of the battery 124, a battery current Ib from a current sensor (not shown) installed at the output terminal of the battery 124, a charge and discharge voltage Vchg from a voltage sensor installed in the charge and discharge circuit 138, a charge and discharge current Ichg from a current sensor installed in the charge and discharge circuit 138, etc.

[0032] The electronic control unit 130 outputs various control signals via an output port. For example, the electronic control unit 130 outputs a display control signal to the display device 150, a communication control signal to the communication device 152, and an air conditioner control signal to the air conditioner device 154. In addition, the electronic control unit 130 outputs a switching control signal for switching a switching element (not shown) to the inverter 123 for driving the motor 122, a drive control signal to a system main relay (not shown) installed near the battery 124, and a drive control signal to a charge and discharge relay (not shown) installed in the charge and discharge circuit 138. The electronic control unit 130 communicates with the navigation system 156, and the navigation system 156 displays various information and performs route guidance. The electronic control unit 130 is connected to a communication line 140, and this communication line 140 is used to communicate with the charging ECU 30 side of the charging device 20 when the charging connector 28 of the charging device 20 is connected to the connector 139. When the charging connector 28 is connected to the connector 139, the communication line 140 is connected to the communication line 32.

[0033] Next, the operation of the charging device 20 configured in this way, particularly the operation when charging the battery 124 of the electric vehicle 120, will be described. Figure 3 It is a flowchart showing an example of a charging process mainly executed by the charging ECU 30. The charging process starts by first connecting the charging connector 28 to the connector 39 of the electric vehicle 120 (S100) and starting communication between the electronic control unit 130 of the electric vehicle 120 and the charging ECU 30 (S110).

[0034] Next, the charging ECU 30 receives a charging current command Ichg* (S120) from the electronic control unit 130 of the electric vehicle 120. The charging current command Ichg* is set by the electronic control unit 130 as a charging current for efficiently charging the storage battery 124 based on the state of charge SOC of the storage battery 124, the temperature Tb, etc. Next, the charging ECU 30 sets the priority order (S130) of each power unit 24(1) to 24(n) as the order for charging. This process is carried out by Figure 4 the priority order setting process exemplified.

[0035] In Figure 4 the priority order setting process, first, the outputtable powers P(1) to P(n) of each power unit 24(1) to 24(n) are input (S200). Then, the variable k is set to the value 1 (S210), and the power unit with the maximum outputtable power is given the order (k) until the variable k coincides with n (S240). At the same time, the process of deleting the power unit for which the order has been set from the additional order process (S220) and the process of incrementing the variable k by 1 (S230) are repeated. Through such a process, the priority orders (1) to (n) are set for each power unit 24(1) to 24(n). In addition, since the smaller the thermal damage of the power unit, the larger the outputtable power is set, the priority order is set in ascending order of thermal damage.

[0036] When the priority orders (1) to (n) as the order for charging are set in each power unit 24(1) to 24(n) in this way, a charging power command P* is set based on the charging current command Ichg* (S140). Next, the power units used for charging are set in the order of the priority orders (1) to (n) until the sum of the outputtable powers of the set power units exceeds the charging power command P* (S150). Now, consider the case where the power unit device 22 has eight power units 24(1) to 24(8), and the outputtable powers P(1) to P(8) of each power unit 24(1) to 24(8) are as shown in the Figure 5 exemplified list, and the charging power command P* is 50 kW. In this case, the priority order of each power unit 24(1) to 24(8) is 1, 2, 7, 5, 3, 6, 8, 4. The power units used are the power units 24(1), 24(2), 24(5), 24(8), 24(4), 24(6) with the priority orders from 1 to 6.

[0037] When the power units for charging are set, the power commands P(n)* of each power unit are set (S160), and charging is started using the power commands P(n)* of each power unit (S170). In Figure 5In the example of the list, the power command P(n) of each power unit can be set to output 10 kW for the power units 24(1), 24(2), 24(5), 24(8) with little thermal damage, 8 kW for the power unit 24(4) with thermal damage, and 2 kW for the power unit 24(6). For the power units 24(4) and 24(7), it can also be set to 5 kW or the like.

[0038] Then, wait until it is determined that charging is completed (S180), perform charging completion processing (S190), and end this processing. Charging completion is determined when the battery 124 is fully charged and sent from the electronic control unit 130, when the user instructs charging completion, etc. As the charging completion processing, it includes stopping the operation of each of the power units 24(1) to 24(n), disconnecting a relay (not shown), and the like.

[0039] In the charging device 20 of the embodiment described above, priorities are determined for the power units 24(1) to 24(n) in the order of decreasing output power (increasing order of thermal damage), and the power units used for charging the battery 124 are set in the order of priorities to perform charging. Thereby, it is possible to select a power unit with less thermal damage and a larger output power among the plurality of power units 24(1) to 24(n) to charge the battery 124 mounted on the electric vehicle 120. In addition, since the larger the output power of the power unit (the closer the output power value is to the maximum output value), the higher the efficiency of the output, it is possible to efficiently charge the battery 124.

[0040] In the charging device 20 of the embodiment, priorities are set for the power units 24(1) to 24(n) in the order of decreasing output power (increasing order of thermal damage). However, for power units having the same output power, the priority of the power unit used in the previous charging of the battery 124 can also be lowered. Figure 6An example of the priority setting process in this case is shown. In this example, the outputtable power P(1) to P(n) of each power unit 24(1) to 24(n) is input (S300), the value 1 is set for the variable k (S310), and the processes of S320 to S370 are repeatedly performed until the variable k matches n (S380). In the repeated process, first, the power unit with the maximum outputtable power is extracted (S320), the number of the extracted power units is set as the extraction number D, and the value 0 is set for the counter C (S330). Then, the process of incrementing the counter C by 1 (S340) and the process of setting the last used power unit among the extracted power units as the rank (k + D - C) and deleting the power unit with the set order from the order assignment process (S350) are repeatedly performed until the counter C matches the extraction number D (S360). For example, consider the case where at k = 1, three power units 24(1), 24(2), and 24(3) are extracted, the power unit 24(1) was used in the previous charge, the power unit 24(2) was not used in the previous charge but was used in the charge before the previous one, and the power unit 24(3) was not used in the previous and the charge before the previous ones. In this case, the order of the power units 24(1), 24(2), and 24(3) is 3, 2, 1. In this way, for power units with the same outputtable power, the priority is set according to the order of previous use, and the priority of the power unit used in the previous time is decreased. When the ranks of the power units with the extraction number D are set, the value obtained by adding the extraction number D to k is set as the new k (S370).

[0041] If the priority setting process of the modification example is used Figure 6 , not only can the priority of each power unit 24(1) to 24(n) be determined in the order of decreasing outputtable power (increasing order of thermal damage), but also for power units with the same outputtable power, the priority can be determined in the order of use. As a result, the situation where only a part of the power units with the same outputtable power are used can be suppressed. Therefore, the situation where the burden is only biased towards a part of the power units can be suppressed, and the life of the power units can be averaged. Therefore, power units with relatively small thermal damage and relatively large outputtable power among the plurality of power units 24(1) to 24(n) can be appropriately selected to charge the storage battery 124 mounted on the electric vehicle 120.

[0042] Describe the correspondence between the main elements of the embodiment and the main elements of the invention described in the Summary of the Invention section. In the embodiment, the plurality of power units 24(1) to 24(n) correspond to the "plurality of power output devices", and the electric vehicle 120 corresponds to the "vehicle". In addition, in the embodiment, the storage battery 124 corresponds to the "power storage device", the charging ECU 30 corresponds to the "charging control device", and the charging device 20 corresponds to the "charging device".

[0043] In addition, the correspondence between the main elements of the embodiment and the main elements of the invention described in the Summary of the Invention section is an example for specifically explaining the manner in which the embodiment implements the invention described in the Summary of the Invention section, and thus is not used to limit the elements of the invention described in the Summary of the Invention section. That is, the interpretation of the invention described in the Summary of the Invention column should be based on the description in that column, and the embodiment is merely a specific example of the invention described in the Summary of the Invention column.

[0044] The present disclosure has been described using embodiments, but the present disclosure is not limited to these embodiments, and of course, can be implemented in various ways without departing from the spirit of the present disclosure.

[0045] The present disclosure can be applied to the manufacturing industry of charging devices and the like.

Claims

1. A charging device, comprising: a plurality of power output devices; and a charging control device that, based on a control instruction from a vehicle, charges a power storage device mounted on the vehicle using at least some of the plurality of power output devices. The charging control device sets the power output devices for charging the power storage device based on the thermal damage of the plurality of power output devices.

2. The charging device according to claim 1, wherein the charging control device determines the priority order of the plurality of power output devices in ascending order of the thermal damage, and sets the power output devices for charging the power storage device in the order of the priority order.

3. The charging device according to claim 2, wherein the control instruction is a charging power instruction, the charging control device sets the power output devices before the position where the cumulative value exceeds the charging power instruction when cumulatively adding the available output power of the power output devices in the order of the priority order as the power output devices for charging the power storage device.

4. The charging device according to claim 2 or 3, wherein the larger the available output power of the power output device, the smaller the charging control device determines the thermal damage to be.

5. The charging device according to any one of claims 1 to 3, wherein the charging control device reduces the priority order of the power output devices used in the previous charging of the power storage device.

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