Charging equipment

Abstract

When the temperature of the charging equipment is low, the heat loss of the charging equipment is used to perform temperature compensation, etc. [Solution] When the temperature of the charging equipment 10 is below a predetermined temperature, relay S3 is turned ON (connected), and the bidirectional converter 11 converts AC power to DC power, and the bidirectional converter 12 converts DC power to AC power. As a result, the temperature of the charging equipment 10 can be raised due to heat loss (heat generation) caused by circulating power.

Description

Technical Field

[0001] The present disclosure relates to charging equipment.

Background Art

[0002] Japanese Patent Application Laid-Open No. 2018-129913 (Patent Document 1) describes charging a power storage device mounted on a vehicle by a DC charging equipment that supplies DC power.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the charging equipment is installed in a cold region or the like, it is preferable to perform temperature compensation of internal devices and melt snow adhering to the equipment. Patent Document 1 does not disclose these points.

[0005] An object of the present disclosure is to perform temperature compensation and the like by utilizing the heat loss of the charging equipment when the temperature of the charging equipment is low.

Means for Solving the Problems

[0006] The charging equipment of this disclosure is a charging equipment that converts AC power to DC power and supplies it to a vehicle. The charging equipment includes a first bidirectional converter (11) that converts AC power supplied to a first AC power line (L11) to DC power and outputs it to a first DC power line (L2), and converts DC power supplied to the first DC power line (L2) to AC power and outputs it to the first AC power line (L11); a second bidirectional converter (12) that converts AC power supplied to a second AC power line (L12) to DC power and outputs it to a second DC power line (L3), and converts DC power supplied to the second DC power line (L3) to AC power and outputs it to the second AC power line (L12); and a control device (20). The first AC power line (L11) and the second AC power line (L12) are connected to an AC power source (PG) via a common AC power line (L1). The first DC power line (L2) is connected to the first charging connector (30A) via the first switch (S1). The second DC power line (L3) is connected to the second charging connector (30B) via the second switch (S2). The first DC power line (L2) on the first bidirectional converter (11) side of the first switch (S1) and the second DC power line (L3) on the second bidirectional converter (11) side of the second switch (S2) are connected via the third switch (S3). When the temperature of the charging equipment is below a predetermined temperature, the control device (20) connects the third switch (S3) and controls one of the first bidirectional converter (11) and the second bidirectional converter (12) to convert AC power to DC power, and the other to convert DC power to AC power.

[0007] In this configuration, when the temperature of the charging equipment is below a predetermined temperature, the third switch (S3) is connected, and one of the first bidirectional converter (11) and the second bidirectional converter (12) is controlled to convert AC power to DC power, while the other is controlled to convert DC power to AC power. A current (circulating power) flows through the first bidirectional converter (11) and the second bidirectional converter (12), and the heat loss due to this circulating power causes the temperature of the charging equipment to rise. As a result, when the temperature of the charging equipment is low, temperature compensation can be performed by utilizing the heat loss of the charging equipment. [Effects of the Invention]

[0008] According to this disclosure, when the temperature of the charging equipment is low, temperature compensation can be performed by utilizing the heat loss of the charging equipment. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of the charging equipment according to this embodiment. [Figure 2] This flowchart shows an example of a temperature increase operation process performed by the ECU. [Figure 3] (A) and (B) are diagrams illustrating the temperature rise due to circulating power. [Modes for carrying out the invention]

[0010] The embodiments of this disclosure will be described in detail below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated.

[0011] Figure 1 is a schematic diagram of the charging equipment 10 according to this embodiment. The charging equipment 10 is an external charger that supplies DC power to the electric vehicle 50 and charges (externally charges) the battery 100 mounted on the electric vehicle 50. The electric vehicle 50 runs when a drive motor (not shown) is driven by the power stored in the battery 100. The electric vehicle 50 is equipped with an inlet 80. When the charging connector 30 of the charging equipment 10 is connected to the inlet, the battery 100 is charged via the charging circuit 70. The charging circuit 70 is controlled by the ECU (Electronic Control Unit) 60 of the electric vehicle 50.

[0012] The charging equipment 10 includes a bidirectional converter 11, a bidirectional converter 12, an ECU 20, a temperature sensor 25, relays S1, S2, and S3. These are arranged inside the housing of the charging equipment 10.

[0013] The bidirectional converters 11 and 12 are bidirectional AC / DC converters capable of converting AC power to DC power and vice versa. The bidirectional converters 11 and 12 may be composed of, for example, an inverter, a DC / DC converter, etc.

[0014] The power grid PG is a commercial power source, for example, a single-phase AC 200V or three-phase AC 200V AC power source. The bidirectional converters 11 and 12 convert the AC power supplied from the power grid PG into DC power and supply DC charging power to the electric vehicle 50. The bidirectional converter 11 is connected to the power grid PG via power lines L11 and L1. The bidirectional converter 11 corresponds to an example of the “first bidirectional converter” in this disclosure, power line L11 corresponds to the “first AC power line” in this disclosure, and power line L1 corresponds to the “common AC power line” in this disclosure. The bidirectional converter 12 is connected to the power grid PG via power lines L12 and L1. The bidirectional converter 12 corresponds to an example of the “second bidirectional converter” in this disclosure, and power line L12 corresponds to the “second AC power line” in this disclosure.

[0015] The bidirectional converter 11 is connected to the charging connector 30A via a power line L2. The DC power output from the bidirectional converter 11 is transmitted through the power line L2 and supplied to the electric vehicle 50 via the charging connector 30A. A relay S1 is placed on the power line L2 to disconnect the bidirectional converter 11 from the charging connector 30A. The power line L2 corresponds to the "first DC power line" in this disclosure, and the relay S1 corresponds to the "first switch" in this disclosure.

[0016] The bidirectional converter 12 is connected to the charging connector 30B via a power line L3. The DC power output from the bidirectional converter 12 is transmitted via the power line L3 and supplied to the electric vehicle 50 via the charging connector 30B. A relay S2 is provided on the power line L3 to disconnect the bidirectional converter 12 and the charging connector 30B. The power line L3 corresponds to the "second DC power line" in this disclosure, and the relay S2 corresponds to the "second switch" in this disclosure.

[0017] The power line L2 on the bidirectional converter 11 side from the relay S1 and the power line L3 on the bidirectional converter 12 side from the relay S2 are connected by a power line L4. A relay S3 is arranged on the power line L4. The relay S3 cuts off the connection between the power line L2 and the power line L3. The relay S3 corresponds to the "third switch" of the present disclosure. The relays S1, S2, and S3 are normally open relays.

[0018] The temperature sensor 25 detects the temperature T1 of the charging facility 10. The temperature T1 may be the temperature of the housing of the charging facility 10 or the temperatures of the bidirectional converters 11 and 12.

[0019] The ECU 20 is composed of a processor, a memory, etc., and controls the bidirectional converters 11 and 12 and the relays S1 to S3. The ECU 20 corresponds to an example of the "control device" of the present disclosure. FIG. 2 is a flowchart showing an example of the temperature-rising operation process executed by the ECU 20. This flowchart is repeatedly processed at predetermined intervals.

[0020] Referring to FIG. 2, in step (hereinafter, steps are abbreviated as "S") 10, the temperature T1 is detected by the temperature sensor 25. In S11, it is determined whether the temperature T1 is below a predetermined temperature A. The predetermined temperature A may be set based on the need for temperature compensation of the internal devices of the charging facility 10, snow melting, etc. If the temperature T1 is below the predetermined temperature A, an affirmative determination is made and the process proceeds to S12. When the temperature T1 is higher than the predetermined temperature A, a negative determination is made and the process proceeds to S14.

[0021] In S12, the circulating power CP is calculated. The circulating power is the power for converting DC power into AC power in the bidirectional converter 11 or the bidirectional converter 12. The circulating power CP is calculated based on the heat loss (the amount of heat generated during power conversion) generated in the power conversion of the bidirectional converters 11 and 12, the temperature T1, etc. For example, it is set in advance by experiments or the like such that the lower the temperature T1, the larger the circulating power CP.

[0022] In S13, relay S3 is turned ON (connected), and the bidirectional converters 11 and 12 are controlled so that circulating power CP occurs, and this routine is stopped. For example, the bidirectional converter 11 is controlled to convert AC power into DC power, and the bidirectional converter 12 is controlled to convert DC power into AC power to generate circulating power CP.

[0023] In S14, in S13, relay S3 is turned OFF (disconnected), the operations of the bidirectional converters 11 and 12 are stopped, and this routine is stopped.

[0024] Figure 3 is a diagram for explaining the temperature rise due to the circulating power CP. Figure 3(A) shows the circulating power CP in the present embodiment. When the circulating power CP calculated in S12 is 50 kw, the bidirectional converter 11 performs power conversion (AC→DC) of 50 kW. The DC power output from the bidirectional converter 11 is input to the bidirectional converter 12 (power line L3) via the power line L4, and the bidirectional converter 12 performs power conversion (DC→AC) of 50 kW. The AC power output from the bidirectional converter 12 is input to the bidirectional converter 11 via the power lines L12 and L11, and is power-converted (AC→DC) by the bidirectional converter 11. When the heat loss (heat generation amount) due to the bidirectional converters 11 and 12 corresponds to 1 kW, normally, 1 kW of AC power is supplied from the power system PG.

[0025] According to this embodiment, when the temperature T1 of the charging facility 10 is lower than the predetermined temperature A, relay S3 is turned ON (connected), and the bidirectional converter 11 is controlled to convert AC power into DC power. Then, the bidirectional converter 12 is controlled to convert DC power into AC power so that a current (circulating power CP) circulating between the bidirectional converter 11 and the bidirectional converter 12 flows. The temperature of the charging facility 10 rises due to the loss heat caused by this circulating power CP. Thereby, when the temperature T1 of the charging facility 10 is low, temperature compensation and the like can be performed by utilizing the heat loss of the charging facility 10.

[0026] Alternatively, the bidirectional converter 12 may be controlled to convert AC power to DC power, and the bidirectional converter 11 may be controlled to convert DC power to AC power, so that a current (circulating power CP) flows through the bidirectional converter 12 and the bidirectional converter 11.

[0027] (modified version) Even when the electric vehicle 50 is being charged, if the temperature T1 is below a predetermined temperature A, the charging equipment 10 may be heated using the heat lost due to the circulating power CP. Figure 3(B) illustrates the circulating power CP in a modified example.

[0028] In Figure 3(B), the charging connector 30A is connected to the inlet 80 of the electric vehicle 50, and relay S1 is turned ON (connected). The DC power converted by the bidirectional converter 11 is supplied to the electric vehicle 50, and the battery 100 is charged. During this charging, if the temperature T1 is below a predetermined temperature A, relay S3 is turned ON (connected), and the bidirectional converter 12 is controlled to convert the DC power to AC power, thereby generating circulating power CP. For example, if the circulating power CP calculated in S12 (Figure 2) is 25 kW, and the charging power to the electric vehicle 50 is 50 kW, the bidirectional converter 11 performs a 75 kW power conversion (AC to DC). Of the DC power output from the bidirectional converter 11, 50 kW is supplied to the electric vehicle 50 as charging power, and the remaining 25 kW of DC power is input to the bidirectional converter 12 (power line L3) via power line L4. The bidirectional converter 12 performs 25kW of power conversion (DC to AC). The AC power output from the bidirectional converter 12 is input to the bidirectional converter 11 via power lines L12 and L11. If the heat loss (heat generation) by the bidirectional converters 11 and 12 is equivalent to 1kW, then under normal conditions, 76kW of AC power is supplied from the power grid PG.

[0029] As shown in this modified example, when charging the electric vehicle 50, a bidirectional converter that is stopped may be used to perform power conversion so that circulating power CP is generated. In this case, if the amount of heat generated (heat loss) by the bidirectional converter that is charging the electric vehicle 50 is insufficient to raise the temperature of the charging equipment 10, a bidirectional converter that is stopped may be used to perform power conversion so that circulating power CP is generated.

[0030] In the above embodiment, two bidirectional converters were used, but there may be three or more bidirectional converters. If the bidirectional converter is an air-cooled converter, when the temperature T1 is below a predetermined temperature A, cooling air may be circulated inside the charging equipment 10. If the bidirectional converter is water-cooled, the passage for cooling water (insulating antifreeze) and the radiator may be placed inside the charging equipment 10 or in the area to be melted down, and when the temperature T1 is below a predetermined temperature A, the cooling water may be used to raise the temperature inside the charging equipment 10 or in the area to be melted down.

[0031] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of symbols]

[0032] 10 Charging equipment, 11,12 Bidirectional converters, 20,60 ECUs, 25 Temperature sensors, 30 Charging connectors, 50 Electric vehicles, 70 Charging circuits, 80 Inlets, 100 Batteries, L1,L11,L12,L2,L3,L4 Power lines, PG Power system, S1,S2,S3 Relays.

Claims

[Claim 1] A charging system that converts AC power to DC power and supplies it to a vehicle, A first bidirectional converter that converts AC power supplied to a first AC power line into DC power and outputs it to a first DC power line, and converts DC power supplied to the first DC power line into AC power and outputs it to the first AC power line, A second bidirectional converter that converts AC power supplied to a second AC power line into DC power and outputs it to a second DC power line, and converts DC power supplied to the second DC power line into AC power and outputs it to the second AC power line, Includes a control device, The first AC power line and the second AC power line are connected to an AC power source via a common AC power line. The first DC power line is connected to the first charging connector via the first switch. The second DC power line is connected to the second charging connector via the second switch. The first DC power line on the first bidirectional converter side from the first switch and the second DC power line on the second bidirectional converter side from the second switch are connected via the third switch. The control device, when the temperature of the charging equipment is lower than a predetermined temperature, A charging system comprising the third switch, wherein one of the first bidirectional converter and the second bidirectional converter is controlled to convert AC power to DC power, and the other is controlled to convert DC power to AC power.

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