Electric vehicles

Abstract

To safely continue charging of a battery even if a hood of a housing of an on-vehicle charging device is opened when the battery is charged using the on-vehicle charging device.SOLUTION: An electric vehicle includes: a battery: an on-vehicle charging device configured to charge the battery using electric power from an external power supply; a cooling device configured to cool the on-vehicle charging device by supplying a refrigerant to the on-vehicle charging device; a fan configured to cool the refrigerant; a housing configured to house the on-vehicle charging device and the fan; a hood openably and closably provided in the housing so as to cover the on-vehicle charging device and the fan; and a control device configured to stop the fan when the battery is charged with the electric power from the external power supply and to reduce the electric power to be supplied from the on-vehicle charging device to the battery, compared to when the hood is closed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to an electric vehicle including a battery and an in-vehicle charger for charging the battery using power from an external power source.

Background Art

[0002] Conventionally, an electric vehicle including a high-voltage battery that can be charged using an in-vehicle charger connected to a household power supply or an external rapid charger, and an inverter that receives power supply from the high-voltage battery is known (see, for example, Patent Document 1). In this electric vehicle, when it is detected that the hood covering the storage portion for storing the inverter is opened during charging of the high-voltage battery using the in-vehicle charger or the rapid charger, the power supply from the high-voltage battery to the inverter is stopped.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the power supply to the inverter is stopped in response to the opening operation of the hood as in the above conventional electric vehicle, the charging of the high-voltage battery is stopped, and it becomes difficult to sufficiently secure the SOC of the high-voltage battery.

[0005] Therefore, the main object of the present disclosure is to enable the charging of the battery to be safely continued even when the hood of the housing portion of the in-vehicle charger is opened while the battery is being charged using the in-vehicle charger.

Means for Solving the Problems

[0006] The electric vehicle of this disclosure includes a battery, an on-board charging device for charging the battery using power from an external power source, a cooling device for supplying a refrigerant to the on-board charging device to cool the on-board charging device, and a fan for cooling the refrigerant, wherein the electric vehicle includes a housing for housing the on-board charging device and the fan, a hood that is openable and closable and provided in the housing so as to cover the on-board charging device and the fan, and a control device that stops the fan and reduces the power supplied from the on-board charging device to the battery compared to when the hood is closed, when the battery is being charged by power from the external power source and the hood is open.

[0007] In the electric vehicle of this disclosure, an on-board charging device for charging the battery using power from an external power source and a fan for cooling the refrigerant that absorbs heat from the on-board charging device are housed within a housing. Furthermore, when the battery is being charged by power from an external power source and the hood is open, the fan is stopped, and the power supplied from the on-board charging device to the battery is reduced compared to when the hood is closed. This ensures safety when the hood is open by stopping the fan, and suppresses the temperature rise of the on-board charging device that occurs when the fan stops by reducing the power supplied from the on-board charging device to the battery. As a result, when the battery is being charged using the on-board charging device, it becomes possible to safely continue charging the battery even if the hood of the housing of the on-board charging device is open.

[0008] Other electric vehicles of the present disclosure include a battery, an on-board charging device for charging the battery using power from an external power source, a cooling device for supplying a refrigerant to the on-board charging device to cool the on-board charging device, and a fan for cooling the refrigerant, wherein the electric vehicle includes a housing for housing the on-board charging device and the fan, a hood that is openable and closable and provided in the housing so as to cover the on-board charging device and the fan, and a control device that stops the fan when the battery is being charged by power from the external power source and the hood is open, and increases the flow rate of the refrigerant supplied from the cooling device to the on-board charging device compared to when the hood is closed, provided that the temperature of the refrigerant is above a predetermined temperature.

[0009] In other electric vehicles of this disclosure, an on-board charging device for charging the battery using power from an external power source and a fan for cooling the refrigerant that absorbs heat from the on-board charging device are housed within a compartment. Furthermore, the fan is stopped when the battery is being charged by power from an external power source and the hood is open. In addition, when the battery is being charged by power from an external power source and the hood is open, the flow rate of the refrigerant supplied from the cooling device to the on-board charging device is increased compared to when the hood is closed, provided that the refrigerant temperature is above a predetermined temperature. This ensures safety when the hood is open by stopping the fan, and also suppresses the temperature rise of the on-board charging device that occurs when the fan stops by increasing the flow rate of the refrigerant supplied from the cooling device to the on-board charging device. As a result, when the battery is being charged using the on-board charging device, it becomes possible to safely continue charging the battery even if the hood of the housing of the on-board charging device is open. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram illustrating the electric vehicle disclosed herein. [Figure 2] Figure 1 is a control block diagram of the electric vehicle. [Figure 3]This flowchart shows an example of a routine that is executed when charging the battery using the on-board charging device of the electric vehicle shown in Figure 1. [Figure 4] This flowchart shows another example of a routine that is executed when charging the battery using the on-board charging device of the electric vehicle shown in Figure 1. [Modes for carrying out the invention]

[0011] Next, with reference to the drawings, embodiments for carrying out the invention of this disclosure will be described.

[0012] Figure 1 is a schematic diagram showing the electric vehicle 1 of the present disclosure. The electric vehicle 1 shown in the figure is an electric vehicle (BEV) or plug-in hybrid vehicle (PHEV) that includes a battery 2, a power control unit (hereinafter referred to as "PCU") 3, an on-board charging device 4 for charging the battery 2 with power from an external power source (not shown), such as a household power supply (AC power) or a fast charger (DC power) installed at a gas station, and a motor generator (three-phase AC motor) MG that exchanges power with the battery 2 via the PCU 3 and outputs driving power and regenerative braking force.

[0013] Battery 2 is a high-voltage battery comprising a plurality of battery modules (battery stack) connected in series and a battery case housing the plurality of battery modules, and is mounted, for example, under the floor (below the floor panel) of the electric vehicle 1. Each battery module of Battery 2 includes a plurality of battery cells (not shown) connected in series or in parallel. Each battery cell is, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery. PCU 3 is connected to Battery 2 via a positive-side power line, a negative-side power line, and a system main relay. PCU 3 includes an inverter (drive circuit) that drives the motor generator MG, a boost converter that can boost the power from Battery 2 and step down the voltage from the motor generator MG, a rechargeable capacitor (not shown), and the like.

[0014] The on-board charging device 4 includes a charging control device (hereinafter referred to as "charging ECU"; see Figure 2) 4c, an AC charger, first and second charging relays, and a case housing these electronic devices (not shown). The charging ECU 4c is a microcomputer (not shown) including a CPU, ROM, RAM, etc., which controls the AC charger, etc., and also controls the opening and closing of the first and second charging relays. The AC charger includes an AC / DC converter that converts AC power to DC power, and a DC / DC converter (neither shown) that boosts the DC power output from the AC / DC converter. The AC / DC converter of the AC charger is connected to a household power supply via a connector and cable. The DC / DC converter of the AC charger is connected to the positive and negative power lines between the PCU 3 and the system main relay via the first charging relay, connector, and cable. As a result, by operating the AC charger with the system main relay and the first charging relay closed, it becomes possible to charge the battery 2 with power (AC power) from a household power supply (external power supply).

[0015] Furthermore, the electric vehicle 1 includes a power receiving connector that is installed in a charging lid (not shown) and can be connected to the power transmission connector of a rapid charger. This power receiving connector is connected to the positive and negative power lines between the system main relay and the PCU via a second charging relay. This makes it possible to charge the battery 2 with power (DC power) from the rapid charger (external power source) by operating the rapid charger with the system main relay and the second charging relay closed. In addition, the charging ECU 4c of the on-board charging device 4 can exchange information with the control device of the rapid charger via a cable connected to the power receiving connector. The on-board charging device 4 is located in the front compartment (housing section) A of the electric vehicle 1 so as to be positioned above the PCU 3 and the motor generator MG (transaxle). As shown in Figure 1, the front compartment A is provided with a hood F that can be opened and closed to cover various devices such as the on-board charging device 4.

[0016] Furthermore, as shown in Figures 1 and 2, the electric vehicle 1 includes a refrigerant pump 5 and a radiator 6. The refrigerant pump 5, together with a refrigerant tank and refrigerant passage RP (not shown), constitutes a cooling system that cools the on-board charging device 4. The refrigerant pump 5 is controlled by an electronic control unit (hereinafter referred to as "ECU") 10, and draws refrigerant from the refrigerant tank and circulates it through the refrigerant passage RP to a heat exchange section provided in the case of the on-board charging device 4. The radiator 6 also includes a heat exchange section 7 incorporated in the refrigerant passage RP between the discharge port of the refrigerant pump 5 and the refrigerant inlet of the heat exchange section of the on-board charging device 4, and a fan (electric fan) 8 controlled by the ECU 10 to supply air to the heat exchange section 7. As shown in Figure 1, the radiator 6 is located at the front of the front compartment A of the electric vehicle 1, and the fan 8 is covered by a hood F.

[0017] The ECU10 is a microcomputer that includes a CPU, ROM, RAM, etc. The ECU10 controls the refrigerant pump 5 and the fan 8 of the radiator 6 while the battery 2 is being charged by power from an external power source. The ECU10 acquires signals from the temperature sensor T, which detects the temperature Tr of the refrigerant flowing into the heat exchange section (refrigerant inlet) of the onboard charging device 4, and signals from the hood open / close detection switch S, and also exchanges information with the charging ECU4c of the onboard charging device 4. The hood open / close detection switch S outputs an OFF signal when the hood F of the front compartment A is closed, and an ON signal when the hood F is open.

[0018] Figure 3 is a flowchart showing an example of a routine that is repeatedly executed by the ECU 10 at predetermined intervals (minute intervals) when the battery 2 is charged by power from an external power source.

[0019] At the start of the routine in FIG. 3, the ECU 10 acquires a signal from the hood opening / closing detection switch S (step S100), and determines whether the hood F of the front compartment A of the electric vehicle 1 is closed (step S110). When the hood F of the front compartment A is closed (step S110: YES), the ECU 10 operates the refrigerant pump 5 and operates the fan 8 of the radiator 6 (step S120). Further, the ECU 10 transmits a notification to the charging ECU 4c of the in-vehicle charging device 4 that there is no need to limit the power (DC power) supplied from the in-vehicle charging device 4 to the battery 2 (step S130), and once terminates the routine in FIG. 3.

[0020] On the other hand, when the hood F of the front compartment A is open (step S110: NO), the ECU 10 stops the fan 8 of the radiator 6 while operating the refrigerant pump 5 (step S140). Further, the ECU 10 transmits a notification to the charging ECU 4c of the in-vehicle charging device 4 that the power (DC power) supplied from the in-vehicle charging device 4 to the battery 2 should be limited (step S150), and once terminates the routine in FIG. 3. The charging ECU 4c of the in-vehicle charging device 4 reduces the power supplied from the in-vehicle charging device 4 to the battery 2 as compared with when the hood F is closed in accordance with the instruction from the ECU 10 in step S150.

[0021] That is, when the battery 2 is charged by the power from the household power supply, the charging ECU 4c of the in-vehicle charging device 4 controls the AC charger so that the power (current) supplied from the AC charger to the battery 2 becomes a predetermined constant value lower than the power (current) supplied to the battery 2 when the hood F is closed. When the battery 2 is charged by the power from the rapid charger, the charging ECU 4c of the in-vehicle charging device 4 transmits a power reduction request to the rapid charger so that the power supplied from the rapid charger to the power receiving connector becomes a predetermined constant value lower than the power supplied to the power receiving connector when the hood F is closed.

[0022] As described above, in the electric vehicle 1, an in-vehicle charging device 4 for charging the battery 2 using electric power from an external power source such as a household power supply, and a radiator 6 (fan 8) for cooling the refrigerant that has taken heat from the in-vehicle charging device 4 are housed in the front compartment A. Then, when the battery 2 is charged by the electric power from the external power source and the hood F of the front compartment A is open, the fan 8 of the radiator 6 is stopped, and the electric power supplied from the in-vehicle charging device 4 to the battery 2 is reduced compared to when the hood F is closed (steps S140, S150).

[0023] Thereby, by stopping the fan 8, it is possible to ensure safety in the state where the hood F is open. Also, by reducing the electric power supplied from the in-vehicle charging device 4 to the battery 2, it becomes possible to reduce the burden of cooling by the refrigerant from the refrigerant pump 5. Therefore, it is possible to suppress the temperature rise of the in-vehicle charging device 4 accompanying the stop of the fan 8 and suppress the charging of the battery 2 from being stopped by the overheat protection function of the in-vehicle charging device 4.

[0024] As a result, when the battery 2 is charged using the in-vehicle charging device 4, even if the hood F of the front compartment A in which the in-vehicle charging device 4 is housed is open, it becomes possible to safely continue charging of the battery 2. Note that the charging ECU 4c of the in-vehicle charging device 4 may be configured to change the electric power supplied from the in-vehicle charging device 4 to the battery 2 according to the temperature Tr of the refrigerant detected by the temperature sensor T within a range not exceeding the electric power supplied from the in-vehicle charging device 4 to the battery 2 when the hood F is closed, in response to the instruction from the ECU 10 in step S150.

[0025] FIG. 4 is a flowchart showing another routine that can be repeatedly executed by the ECU 10 at predetermined intervals (micro time) instead of the routine of FIG. 3 when the battery 2 of the electric vehicle 1 is charged by the electric power from the external power source.

[0026] At the start of the routine in Figure 4, the ECU 10 obtains the temperature Tr of the refrigerant supplied to the on-board charging device 4, which is detected by the signal from the hood opening / closing detection switch S and the temperature sensor T (step S200), and determines whether or not the hood F of the front compartment A of the electric vehicle 1 is closed (step S210). If the hood F of the front compartment A is closed (step S210: YES), the ECU 10 activates the refrigerant pump 5 and the fan 8 of the radiator 6 (step S220). Furthermore, the ECU 10 controls the rotation speed of the refrigerant pump 5 so that the flow rate of the refrigerant supplied from the refrigerant pump 5 to the radiator 6, i.e., the on-board charging device 4, is a predetermined normal value (step S230), and then terminates the routine in Figure 3.

[0027] On the other hand, if the hood F of the front compartment A is open (step S210: NO), the ECU 10 stops the fan 8 of the radiator 6 while keeping the refrigerant pump 5 running (step S240). Furthermore, the ECU 10 determines whether the temperature Tr of the refrigerant supplied to the on-board charging device 4, which was obtained in step S200, is above a predetermined threshold (specified temperature) Tref determined through experimentation and analysis (step S250).

[0028] If the temperature Tr of the refrigerant supplied to the on-board charging device 4 is less than the threshold Tref (step S250: NO), the ECU 10 controls the rotation speed of the refrigerant pump 5 so that the flow rate of the refrigerant supplied from the refrigerant pump 5 to the on-board charging device 4 is the normal value (step S230), and terminates the routine in Figure 3. If the temperature Tr of the refrigerant supplied to the on-board charging device 4 is greater than or equal to the threshold Tref (step S250: YES), the ECU 10 controls the rotation speed of the refrigerant pump 5 so that the flow rate of the refrigerant supplied from the refrigerant pump 5 to the radiator 6, i.e., the on-board charging device 4, is an increased value which is a predetermined constant value greater than the normal value (step S260), and terminates the routine in Figure 3.

[0029] In electric vehicle 1, where the routine shown in Figure 4 is executed by the ECU 10, the fan 8 of the radiator 6 is stopped when the battery 2 is charged by power from an external power source and the hood F of the front compartment A is open (step S240). Furthermore, when the battery 2 is charged by power from an external power source and the hood F of the front compartment A is open, the flow rate of refrigerant supplied from the refrigerant pump 5 to the on-board charging device 4 is increased compared to when the hood F is closed, provided that the refrigerant temperature Tr is above a threshold (predetermined temperature) Tref (steps S250, S260).

[0030] This ensures safety when the hood F is open by stopping the fan 8. In addition, by increasing the flow rate of refrigerant supplied from the refrigerant pump 5 to the on-board charging device 4, the temperature rise of the on-board charging device 4 due to the stopping of the fan 8 can be effectively suppressed. Therefore, even in the electric vehicle 1 in which the routine in Figure 4 is executed, the temperature rise of the on-board charging device 4 due to the stopping of the fan 8 can be suppressed, and the overheat protection function of the on-board charging device 4 can be prevented from stopping the charging of the battery 2.

[0031] As a result, even in the electric vehicle 1 in which the routine in Figure 4 is executed, when the battery 2 is being charged using the on-board charging device 4, it is possible to safely continue charging the battery 2 even if the hood F of the front compartment A in which the on-board charging device 4 is housed is opened. The ECU 10 of the electric vehicle 1 may be configured to change the flow rate of the refrigerant supplied from the on-board charging device 4 to the refrigerant pump 5 according to the temperature Tr of the refrigerant detected by the temperature sensor T, within a range that does not exceed the power supplied from the on-board charging device 4 to the battery 2 when the hood F is closed.

[0032] Furthermore, the invention disclosed herein is not limited in any way to the embodiments described above, and it goes without saying that various modifications can be made within the scope of this disclosure. Moreover, the embodiments described above are merely one specific form of the invention described in the summary of the invention, and do not limit the elements of the invention described in the summary of the invention. [Industrial applicability]

[0033] The invention disclosed herein can be used in industries such as the electric vehicle manufacturing industry. [Explanation of Symbols]

[0034] 1 Electric vehicle, 2 Battery, 3 Power control unit (PCU), 4 On-board charging device, 4c Charging control unit (Charging ECU), 5 Refrigerant pump, 6 Radiator, 7 Heat exchanger, 8 Fan, 10 Electronic control unit (ECU), A Front compartment, F Hood, RP Refrigerant passage, S Hood open / close detection switch, T Temperature sensor.

Claims

[Claim 1] In an electric vehicle, which includes a battery, an on-board charging device for charging the battery using power from an external power source, a cooling device for supplying a refrigerant to the on-board charging device to cool the on-board charging device, and a fan for cooling the refrigerant, A housing section for housing the on-board charging device and the fan, A hood is provided in the housing so as to be openable and closable so as to cover the in-vehicle charging device and the fan, A control device that stops the fan when the battery is charged by power from the external power source and the hood is open, and increases the flow rate of the refrigerant supplied from the cooling device to the on-board charging device compared to when the hood is closed, provided that the temperature of the refrigerant is above a predetermined temperature. An electric vehicle equipped with [a specific feature / equipment].

Images