Power supply system for electric vehicle

Abstract

The invention provides a power supply system for an electric vehicle, which can reduce the situation that the interior of the vehicle becomes a harsh environment when a collision of the electric vehicle is detected. A power supply system, which is mounted in an electric vehicle including an electric air conditioner in an electrical device, and which has a battery for storing power for travel and the electrical device driven by the power of the battery, is provided with: a circuit for transmitting power from the battery to the electrical device; a switcher provided in the circuit; and a controller that, when a collision of the electric vehicle is detected, controls the switcher to a state in which transmission of power from the battery to the electrical equipment is stopped, and, when a collision of the electric vehicle is detected, performs a determination process relating to air conditioning control of the cabin, and, on the basis of the result of the determination process, controls the switcher to a state in which transmission of power from the battery to the electrical equipment is stopped. The switcher is controlled so as to transmit power from the battery to the electric air conditioner, and the electric air conditioner is driven.

Description

Technical Field

[0001] The invention relates to a power supply system for an electric vehicle. Background Art

[0002] Patent Document 1 describes a vehicle power supply device in which, upon receiving a vehicle collision signal, a motor control device uses power from a backup power supply to discharge vehicle-mounted equipment.

[0003] Prior art literature Patent Literature Patent Document 1: Japanese Patent Application Publication No. 2021-035092 Summary of the invention

[0004] Technical issues If the battery power is completely unusable after a vehicle collision, the interior of the vehicle may become a harsh environment in extremely cold regions or under scorching sun.

[0005] An object of the present invention is to provide a power supply system for an electric vehicle that can reduce the severity of the environment in a vehicle cabin when a collision of the electric vehicle is detected.

[0006] Technical Solution A power supply system for an electric vehicle according to one embodiment of the present invention is characterized in that it includes a battery for storing electric power for traveling, and an electric device driven by the electric power of the battery, and is mounted on the electric vehicle, wherein the electric device includes an electric air conditioner. The power supply system of the electric vehicle comprises: a circuit that transfers power from the battery to the electrical device; a switch, which is disposed in the circuit; and a controller that controls the switch to stop the transmission of power from the battery to the electrical device when a collision of the electric vehicle is detected, When a collision of the electric vehicle is detected, the controller performs a determination process related to air conditioning control of the vehicle cabin, and based on a result of the determination process, controls the switch to transmit power from the battery to the electric air conditioner to drive the electric air conditioner.

[0007] Technical Effects According to the present invention, when a collision of an electric vehicle is detected, it is possible to reduce the harsh environment in the vehicle cabin. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a block diagram showing an electric vehicle equipped with a power supply system according to an embodiment of the present invention.

[0009] Figure 2 It is shown Figure 1 Circuit diagram of the power supply system.

[0010] Figure 3 : is a circuit diagram showing an example of the connection state of the circuit after the collision is detected.

[0011] Figure 4 This is a part of a flowchart showing an example of a control process executed by the controller.

[0012] Figure 5 yes Figure 4 The remainder of the flowchart.

[0013] Figure 6 : is a circuit diagram showing a modification of the circuit of the power supply system according to the embodiment.

[0014] Explanation of symbols 1. Electric vehicles 2a, 2b: driving wheels 3a, 3b: Travel motor 4a, 4b: Converter 5: Battery 6: Driving operation department 7: Controller 7a: Storage 8: Electric air conditioner 8a: Electric compressor 8b: Electric heater 9: Low voltage battery 10: DC / DC Converter 11: First socket 12: Relay 13: Second socket 14: Charger 21: Operation panel 22: Ministry of Communications 23: Collision sensor 24: Position sensor 30: Power System L: Circuit L1: First circuit L2: Second circuit SW1~SW4: Switch SW11: Discharge switch R2: Discharge resistor DETAILED DESCRIPTION

[0015] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0016] Figure 1 This is a block diagram showing an electric vehicle equipped with a power supply system according to an embodiment of the present invention. Figure 2 It is shown Figure 1 Circuit diagram of the power supply system. Figure 1 In the example, the circuit L of the power supply system is simplified.

[0017] The electric vehicle 1 equipped with the power supply system 30 of the present embodiment includes driving wheels 2a, 2b, running motors 3a, 3b for driving the driving wheels 2a, 2b, inverters 4a, 4b for driving the running motors 3a, 3b, respectively, a battery 5 for storing power for running, a driving operation unit 6 for receiving a driving operation by a driver, a controller 7 for controlling the inverters 4a, 4b by receiving a signal from the driving operation unit 6, an electric air conditioner 8 for operating using power from the battery 5, a low-voltage battery 9 for supplying a power supply voltage to a low-voltage device, and a DC / DC converter 10 for generating a power supply voltage for the low-voltage device by receiving power from the battery 5. The low-voltage device includes the controller 7.

[0018] The electric vehicle 1 further includes a first inlet 11 and a relay 12 for inputting a DC external power source for charging the battery 5, and a second inlet 13 and a charger 14 for inputting an AC external power source for charging the battery 5. The first inlet 11 is connected to the first circuit L1 via the relay 12. The second inlet 13 is connected to the first circuit L1 via the charger 14. The charger 14 converts the AC external power source into a DC and transmits it to the battery 5.

[0019] The electric vehicle 1 also includes an operation panel 21 capable of receiving instructions from a passenger, a communication unit 22 capable of communicating with a service facility located at a remote location, a collision sensor 23 for detecting a collision of the electric vehicle 1, and a position sensor 24 for measuring the position of the electric vehicle 1. The communication unit 22 is a structure capable of performing data communication between the service facility and the controller 7 in addition to voice communication between the service facility and the passenger. The collision sensor 23 is, for example, a sensor for detecting the deployment of an airbag, but may be any structure such as an acceleration sensor as long as it can detect a collision. The position sensor 24 measures the position of the electric vehicle 1 using, for example, a positioning system including a positioning satellite.

[0020] The driving wheels 2a are, for example, two front wheels, and the driving wheels 2b are, for example, two rear wheels. It should be noted that one of the travel motors 3a and 3b and one of the inverters 4a and 4b may be omitted, and the front wheels or the rear wheels may be used as driven wheels.

[0021] The driving operation unit 6 includes a steering wheel or other steering part 6a, a brake pedal or other braking part 6b, and an accelerator pedal or other acceleration part 6c. The driving operation unit 6 is operable by the driver, but may be operated by an automatic driving system.

[0022] The battery 5 is, for example, a lithium-ion secondary battery, a nickel-metal hydride secondary battery, etc., but its type is not particularly limited. The battery 5 outputs a voltage higher than the voltage of the low-voltage battery 9 (for example, 100V or more). The low-voltage battery 9 is, for example, a lead battery, but its type is not particularly limited. The low-voltage battery 9 outputs a voltage lower than the voltage of the battery 5 (for example, a 12V voltage).

[0023] The electric air conditioner 8 includes an electric heater 8b and an electric compressor 8a. The electric air conditioner 8 can increase the temperature of the vehicle compartment by delivering the air heated by the electric heater 8b to the vehicle compartment. The electric air conditioner 8 drives the electric compressor 8a to deliver the air cooled by the heat pump to the vehicle compartment, thereby reducing the temperature of the vehicle compartment. The vehicle compartment refers to a space for people to ride in the electric vehicle 1.

[0024] The controller 7 is equivalent to an example of the controller of the present invention included in the power supply system 30. The controller 7 is a microcomputer such as an ECU (Electronic Control Unit), and operates according to a control program stored in the storage unit 7a. The controller 7 controls the converters 4a and 4b by receiving a signal from the driving operation unit 6, thereby controlling the driving of the electric vehicle 1 (referred to as "driving control"). In addition, the controller 7 performs air-conditioning control to adjust the cabin temperature. The air-conditioning control is performed based on instructions from the operation panel 21 or based on conditions that are not dependent on the operation of the passenger. In addition, the controller 7 performs switching control of the circuit L by switching the states of the switches SW1~SW3 provided in the circuit L. In addition, the controller 7 performs control based on collision detection of the electric vehicle 1.

[0025] It should be noted that the driving control, air conditioning control, switching control of the circuit L, and control based on collision detection may not be performed by one controller 7, but may be performed cooperatively by multiple controllers communicating with each other. In this case, the controller that performs the air conditioning control, switching control of the circuit L, and control based on collision detection is equivalent to an example of the controller of the present invention included in the power supply system 30.

[0026] <Circuit and switch> Figure 2 and Figure 3 It is shown Figure 1 Circuit diagram of the power supply system. Figure 2 Indicates the state of circuit L during normal operation. Figure 3FIG. 4 shows an example of the connection state of the circuit L after a collision is detected. Figure 2 and Figure 3 In FIG. 5 , the current flowing out from the anode of the battery 5 is indicated by a thick arrow line.

[0027] The power supply system 30 has a circuit L for transmitting power between a battery 5 and a plurality of electrical devices, and switches SW1 to SW3 provided in the circuit L. In addition, the power supply system 30 may also have a fuse F1 of a fusible type connected in series to the battery 5 or built into the battery 5. Hereinafter, the state in which the switches SW1 to SW3 cut off the circuit is referred to as the off state of the switches SW1 to SW3, and the state in which the switches SW1 to SW3 connect the circuit is referred to as the on state of the switches SW1 to SW3. The switch SW1 among the plurality of switches SW1 to SW3 is equivalent to an example of the first switch of the present invention. The switch SW2 is equivalent to an example of the second switch of the present invention. The switch SW3 is equivalent to an example of the third switch of the present invention.

[0028] The plurality of electrical devices include the inverters 4 a and 4 b , the first inlet 11 , the charger 14 , the DC / DC converter 10 , and the electric air conditioner 8 .

[0029] The electric circuit L includes a first circuit L1 that can normally transmit power between the battery 5 and a plurality of electrical devices, and a second circuit L2 that is used exclusively to transmit the power of the battery 5 to the electric air conditioner 8 after a collision is detected.

[0030] The switches SW1 to SW3 include the switch SW1 as a system main relay provided on the first circuit L1, the switch SW2 capable of disconnecting the second circuit L2, and the switch SW3 capable of disconnecting the first circuit L1 from the second circuit L2. The switch SW1 is an example of the first switch of the present invention. The switch SW2 is an example of the second switch of the present invention. The switch SW3 is an example of the third switch of the present invention.

[0031] The first circuit L1 and the second circuit L2 each have a pair of electric wires connected to the anode and the cathode of the battery 5 , respectively.

[0032] The switches SW1 to SW3 each include a pair of switches capable of disconnecting one and the other of the pair of electric wires. In addition, the switches SW1 and SW2 may also include a pre-charging switch that reduces the inrush current from the battery 5 to the electrical device by inserting a resistor R1 when the circuit is connected. Each switch is a relay, but various switches such as a contactor or a power semiconductor switch may also be applied as long as the transmission of electric power can be disconnected.

[0033] The state of the circuit L having the above-described structure is switched as follows by the control of the switches SW1 to SW3.

[0034] <Break time> When the system of the electric vehicle 1 is stopped, the switches SW1 and SW2 are turned off and the switch SW3 is turned on, thereby disconnecting the first circuit L1 and the second circuit L2 so that power is not transmitted between the battery 5 and the plurality of electrical devices.

[0035] <Normal operation> like Figure 2 As shown, during the normal operation of the electric vehicle 1, by turning on the switch SW1, keeping the switch SW3 turned on, and keeping the switch SW2 turned off, power can be transmitted between the battery 5 and multiple electrical devices via the first circuit L1. At this time, the second circuit L2 is cut off in a manner that power is not transmitted via the second circuit L2. Normal operation refers to the period when the electric vehicle 1 is in a normal state and the system of the electric vehicle 1 is starting, for example, it is equivalent to the period when the electric vehicle 1 is running in a normal state, the period when it can run, the period during the charging control process, etc. The normal state refers to a state where no abnormality such as a collision is detected.

[0036] <When an abnormality occurs> When an abnormality occurs in the electric vehicle 1, the switch SW1 is turned off, the switch SW2 is kept off, and the switch SW3 is turned on, thereby disconnecting the plurality of electrical devices and most of the first circuit L1 and the second circuit L2 from the battery 5. The abnormality occurs when the electric vehicle 1 detects a collision, for example.

[0037] <After the abnormality occurs> like Figure 3 As shown, after an abnormality occurs in the electric vehicle 1, when a predetermined condition described later is satisfied, the switch SW2 is turned on, the switch SW3 is turned off, and the switch SW1 is kept turned off, so that the power of the battery 5 can be transmitted to the electric air conditioner 8 via the second circuit L2. In this state, the electrical equipment (the inverters 4a, 4b, the DC / DC converter 10 or both) other than the electric air conditioner 8 is disconnected from the battery 5.

[0038] The second circuit L2 may be shorter than the first circuit L1. In addition, since it is shorter, the second circuit L2 can be set at a position less susceptible to the impact of the collision of the electric vehicle 1 than the first circuit L1. With such a structure, even if a failure occurs in the first circuit L1 due to the collision of the electric vehicle 1, power can be supplied from the battery 5 to the electric air conditioner 8 via the second circuit L2. In addition, even if a high voltage is output to the second circuit L2, interference of the high voltage on the fault recovery of the electric vehicle 1 can be reduced.

[0039] The power supply system 30 also has a discharge switch SW11 that can connect the electric wire on the anode side of the first circuit L1 to the electric wire on the cathode side via the discharge resistor R2. The discharge resistor R2 has a sufficiently large resistance value, and by turning on the discharge switch SW11, the electric wire on the anode side of the first circuit L1 and the electric wire on the cathode side are connected via the discharge resistor R2. The discharge switch SW11 and the resistor R2 are structures for releasing the charge remaining between the first circuit L1 and the terminals of the electrical device when the switch SW1 is turned off. Even after the switch SW1 is turned off, a high voltage of the capacitor or the like remaining inside the terminals of the electrical device remains. The high voltage can be removed slowly (for example, 10 minutes) by the discharge switch SW11 and the discharge resistor R2.

[0040] In addition, the discharge switch SW11 and the discharge resistor R2 may be provided in the middle of the first electric circuit L1 or in an electric device.

[0041] <Service in case of collision> When the service facility detects a collision of the electric vehicle 1, it communicates with the electric vehicle 1 via the communication unit 22 and provides various services. For example, the service facility makes a voice call to confirm the status of the electric vehicle 1 with the passenger. In addition, the service facility receives the location information of the electric vehicle 1 from the controller 7 of the electric vehicle 1, and makes a request to the rescue team at that location according to the situation. The service facility can predict the time until the rescue team arrives at the location of the electric vehicle 1 based on the location information and the information of the dispatch point of the rescue team. In addition, the service facility has information on the weather and temperature of each location, as well as the forecast thereof.

[0042] When the service facility detects a collision of the electric vehicle 1 and requests a rescue team, it transmits information on the time until the rescue team arrives and information on the weather and temperature at the location of the electric vehicle 1 to the controller 7 through communication.

[0043] <Troubleshooting> The controller 7 has a fault diagnosis function for the electric air conditioner 8. In this function, the controller 7 sends a command to the control circuit of the electric air conditioner 8 to determine whether there is a normal response from the control circuit in response to the command, thereby being able to diagnose whether the electric air conditioner 8 has a fault. The above-mentioned command may include a command to request a response from the control circuit of the electric air conditioner 8, and the above-mentioned response is a response to confirm whether the control circuit is operating. In addition, the above-mentioned command may include a command to operate the movable part of the electric air conditioner 8 (the rotating part of the electric compressor 8a, etc.), and the above-mentioned response may include a response indicating that the movable part is operating normally. In addition, the above-mentioned command may include a command to cause current to flow in the driving part (the electric heating wire of the electric heater 8b, etc.), and the above-mentioned response may include a response indicating that normal current is flowing.

[0044] In addition, the controller 7 has a fault diagnosis function of the battery 5. The battery 5 is equipped with a sensor for detecting leakage and a sensor for detecting heat. In the above functions, the controller 7 monitors the output of the sensor to confirm whether abnormal leakage, abnormal heat, etc. are detected in the battery 5, thereby being able to diagnose whether the battery 5 has no fault.

[0045] <Control Processing During Collision> Figure 4 and Figure 5 An example of a flowchart of the control process executed by the controller is shown. When the controller 7 is started, it executes a process of monitoring the detection of an impact exceeding a threshold value by an acceleration sensor or the like (step S1), and repeats this process during a period when there is no impact exceeding the threshold value. Then, if an impact exceeding the threshold value is detected, the controller 7 advances the process to step S2.

[0046] As a result, if the process is carried out, the controller 7 determines the detection result of the collision sensor 23 and determines whether the airbag has been deployed (step S2). The detection of the deployment of the airbag is equivalent to the detection of the collision of the electric vehicle 1. And, if it has not been deployed, the controller 7 returns the process to step S1 again.

[0047] On the other hand, if the airbag is deployed, the controller 7 notifies the service facility of the collision via the communication unit 22 (step S3). This notification is an automatic notification that does not depend on the operation of the passenger. In addition, the controller 7 switches to a state where the power transmission from the battery 5 to the electrical device is stopped by turning off the switch SW1 (step S4). In addition, the controller 7 starts the discharge of the first circuit L1 by turning on the discharge switch SW11 (step S4). Here, in the case where a plurality of electrical devices each include a circuit for discharge, the controller 7 may also send a command to each electrical device to operate the circuit for discharge to start the discharge.

[0048] Next, the controller 7 performs a judgment process related to the air conditioning control of the cabin of the electric vehicle 1 (specifically, steps S5, S6, S8, and S9 described later). The judgment related to the air conditioning control includes the judgment of the necessity of the air conditioning control, the judgment of whether the air conditioning control can be performed, and the judgment of the settings of the air conditioning control (cooling, heating, intensity, etc.). The judgment process of steps S5 and S6 is equivalent to an example of the first judgment process of the present invention, and the judgment process of steps S8 and S9 is equivalent to an example of the second judgment process of the present invention.

[0049] Here, the controller 7 performs a judgment on the necessity of air-conditioning control as in steps S5 and S6. That is, the controller 7 first estimates the temperature change in the cabin when the electric air conditioner 8 is not driven (step S5). Here, the controller 7 estimates the cabin temperature that changes before the arrival of the rescue team, etc. The controller 7 can obtain information on the estimated time until the arrival of the rescue team, etc. from the service facility, and use a function or data table for estimation to estimate the above-mentioned cabin temperature based on the current cabin temperature and weather and external air information. It should be noted that one purpose of estimating the cabin temperature is to estimate whether the environment of the cabin where the passengers are located is harsh. Therefore, the controller 7 can estimate the value of the cabin temperature after a predetermined time instead of estimating the cabin temperature that changes before the arrival of the rescue team, etc., and can also estimate whether the cabin temperature has become a harsh condition instead of estimating the value of the cabin temperature.

[0050] Next, the controller 7 determines whether the cabin temperature after the change estimated in step S5 is outside the first temperature range, that is, whether it is a severe temperature (step S6). That is, the lower limit value of the first temperature range is set to a threshold value indicating a severe low temperature, such as any value between -15°C and 0°C, and the upper limit value of the first temperature range is set to a threshold value indicating a severe high temperature, such as any value between 35°C and 50°C.

[0051] If the determination result of step S6 is NO (within the first temperature range), the controller 7 maintains the state of the power supply system 30 at that point in time unchanged and ends the control process.

[0052] On the other hand, if the judgment result of step S6 is yes (outside the first temperature range), the controller 7 drives the electric air conditioner 8 using the charge remaining in the first circuit L1 as electric power (step S7). For driving, if the cabin temperature is predicted to be low, the driving is performed to exert a heating effect, and if the cabin temperature is predicted to be high, the driving is performed to exert a cooling effect. The inverters 4a and 4b are provided with relatively large capacitors, and the electric air conditioner 8 can be driven by the charge stored in the capacitors. Through the processing of step S7, the charge to be discharged can be effectively used.

[0053] Next, the controller 7 determines whether the air conditioning control using the power of the battery 5 can be performed as in steps S8 and S9. That is, the controller 7 first performs a fault diagnosis of the electric air conditioner 8 and a fault diagnosis of the battery 5 (step S8). The details of the fault diagnosis are as described above, and the fault diagnosis of the battery 5 includes the detection of leakage. Next, the controller 7 determines the result of the diagnosis (step S9).

[0054] When the judgment result of step S9 is abnormal, the controller 7 maintains the state of the power supply system 30 at that time point unchanged and ends the control process. Thereafter, while the battery 5 is disconnected from the plurality of electrical devices, the discharge of the first circuit L1 continues, and the power supply system 30 enters a state after the collision of the electric vehicle 1.

[0055] On the other hand, if the judgment result of step S9 is normal, the controller 7 turns off the switch SW3 and turns on the switch SW2 (step S10). It should be noted that the normal result of the fault diagnosis is not limited to the state without any abnormality. For example, the normality of the battery 5 refers to the diagnosis result that the power can be output from the battery 5. In addition, the normality of the electric air conditioner 8 refers to the diagnosis result that the electric air conditioner 8 can be driven.

[0056] like Figure 3 As shown, by the process of step S10, the power supply circuit of the electric air conditioner 8 is disconnected from the first circuit L1, and power is supplied from the battery 5 to the electric air conditioner 8 via the second circuit L2. In addition, the electric air conditioner 8 is driven by the power of the battery 5. In step S10, the controller 7 may also perform switching control of the switch SW2 for mitigating the inrush current from the battery 5 by using the pre-charging switch. Even if the process of step S10 is performed, the discharge of the first circuit L1 continues, and a high voltage remains in the first circuit L1 and the electrical equipment (converters 4a, 4b, etc.) connected to the first circuit L1.

[0057] In addition, the controller 7 performs setting processing of the electric air conditioner 8 based on the time until the arrival of the rescue team, etc. and the remaining charge of the battery 5 (step S11). This setting processing is mainly to set the intensity of air conditioning, for example, it is sufficient to set it so as to prevent the remaining charge from running out and the cabin temperature from becoming severe within a period shorter than the time until the arrival. Then, the controller 7 ends this control processing.

[0058] By the control process as described above, when a collision of the electric vehicle 1 is detected and the battery 5 and the electric air conditioner 8 are normal, the air conditioning control is performed as required so that the cabin temperature does not become severe. Therefore, even in the case where the passengers are left in the cabin due to the collision of the electric vehicle 1, it is possible to reduce the situation where the passengers suffer from the cabin temperature.

[0059] The control processing program is stored in a non-transitory computer readable medium such as the storage unit 7a of the controller 7. The controller 7 may also be configured to read a program stored in a portable non-transitory recording medium and execute the program. The portable non-transitory storage medium may also store the control processing program.

[0060] As described above, according to the power supply system 30 of the electric vehicle 1 of the present embodiment, the controller 7 performs a judgment process related to the air conditioning control of the vehicle compartment when a collision of the electric vehicle 1 is detected. Then, based on the result of the judgment process, the controller 7 controls the switches SW2 and SW3 in a manner of transmitting power from the battery 5 to the electric air conditioner 8, and drives the electric air conditioner 8. Therefore, even in a situation where the battery 5 is cut off due to a collision of the electric vehicle 1 and the passengers are left in the vehicle compartment, the electric air conditioner 8 can be driven by the power of the battery 5 according to the situation, and the situation where the passengers suffer due to the temperature of the vehicle compartment can be reduced.

[0061] In addition, according to the power supply system 30 of the electric vehicle 1 of the present embodiment, as one of the judgment processes related to the above-mentioned air conditioning control, the change of the cabin temperature when the electric air conditioner 8 is not driven is estimated, and it is determined whether the estimated cabin temperature is outside the first temperature range. Through such a judgment process, it is possible to determine whether air conditioning control is required, and unnecessary air conditioning control of the electric vehicle 1 after a collision is detected can be avoided.

[0062] In addition, according to the power supply system 30 of the electric vehicle 1 of the present embodiment, as one of the judgment processes related to the above-mentioned air conditioning control, the fault diagnosis of the electric air conditioner 8 and the fault diagnosis of the battery 5 are performed, and the results are judged. Therefore, when an abnormality occurs in the electric air conditioner 8 or the battery 5 due to a collision, etc., the abnormality can be suppressed by trying to drive the electric air conditioner 8 using the power of the battery 5. It should be noted that, in the case where it is known that the possibility of the electric air conditioner 8 having an abnormality is very low, the fault diagnosis of the electric air conditioner 8 can also be omitted. Similarly, in the case where it is known that the possibility of the battery 5 having an abnormality is very low, the fault diagnosis of the battery 5 can also be omitted.

[0063] In addition, according to the power supply system 30 of the electric vehicle 1 of the present embodiment, after a collision is detected, a discharge process is performed to release the charge remaining in the first circuit L1 and between the electrodes of the plurality of electrical devices through the discharge switch SW11. In addition, during the discharge process, the controller 7 uses the above-mentioned charge released, that is, the discharge power to temporarily drive the electric air conditioner 8 according to the conditions. Through such a process, the charge remaining in the first circuit L1 and the electrical devices before the release can be effectively utilized, and the discharge time can be further shortened.

[0064] In addition, according to the power supply system 30 of the electric vehicle 1 of the present embodiment, when the result of the judgment processing of steps S5 and S6 (equivalent to the first judgment processing) is that the cabin temperature is outside the first temperature range, the controller 7 drives the electric air conditioner 8 using the charge before discharge. Thereafter, when the result of the judgment processing of steps S8 and S9 (equivalent to the second judgment processing) is normal, the electric air conditioner 8 is driven using the power of the battery 5. Assuming that there is an abnormality due to a collision in the battery 5 or the electric air conditioner 8, even if the drive control of the electric air conditioner 8 is performed during the discharge process, the possibility of the above-mentioned abnormality developing is very small. Therefore, according to the above-mentioned processing sequence, the drive control of the electric air conditioner 8 with less waste can be achieved.

[0065] In addition, the power supply system 30 of the electric vehicle 1 according to the present embodiment includes a first circuit L1 for transmitting power from the battery 5 to the inverters 4a, 4b and the electric air conditioner 8, and a second circuit L2 capable of transmitting power from the battery 5 to the electric air conditioner 8 without the inverters 4a, 4b. In addition, the power supply system 30 includes a switch SW1 provided on the first circuit L1, a switch SW2 provided on the second circuit L2, and a switch SW3 capable of disconnecting the first circuit L1 from the second circuit L2. Moreover, when the electric air conditioner 8 is driven by the power of the battery 5 after the collision is detected, the controller 7 switches the switches SW1 to SW3 in such a manner that the power of the battery 5 is supplied to the electric air conditioner 8 via the second circuit disconnected from the first circuit. According to this structure, even when the electric vehicle 1 drives the electric air conditioner 8 by the power of the battery 5 after the collision is detected, the high voltage of the first circuit L1 can be removed by discharge. Therefore, it is possible to suppress the inconvenience caused by the high voltage remaining in the first circuit L1 after the collision is detected. Furthermore, since the second electric circuit L2 exists, even when a failure occurs such that the switch SW1 cannot be turned on due to a collision, the electric air conditioner 8 can be driven.

[0066] The above is an explanation of the embodiment of the present invention. However, the present invention is not limited to the above embodiment. For example, in the above embodiment, the circuit L of the power supply system 30 includes the first circuit L1 and the second circuit L2. However, the circuit L may not include the second circuit L2 and supply power from the battery 5 to the electric air conditioner 8 via the first circuit L1 after a collision is detected. In addition, Figure 6 As shown, the following structure may be adopted: the electric air conditioner 8 is connected to the upstream side of the first circuit L1 (ie, the side close to the battery 5), other electrical equipment is connected to the downstream side, and a switch SW4 is provided in the first circuit L1 to disconnect the downstream side. Figure 6 1 is a circuit diagram showing a modified example of the circuit of the power supply system of the embodiment. In the case of this structure, by turning on the switch SW1 and turning off the switch SW4, it is possible to supply power from the battery 5 to the electric air conditioner 8 without the converters 4a and 4b. Therefore, this state can also be set as the state of the circuit L when power is supplied from the battery 5 to the electric air conditioner 8 after the collision is detected. In addition, in the above-mentioned embodiment, an example of controlling in a manner that is not harsh when the cabin temperature is high and when the cabin temperature is low is shown, but for example, for an electric vehicle used in an extremely cold place, it is also possible to control so that it is not harsh only when the cabin temperature is low. In this case, the electric air conditioner may not have a structure that lowers the cabin temperature. On the contrary, for example, for an electric vehicle used in a high temperature place, it is also possible to control so that it is not harsh only when the cabin temperature is high. In this case, the electric air conditioner may not have a structure that increases the cabin temperature. In addition, the details shown in the embodiment can be appropriately changed within the scope of not departing from the main purpose of the invention.

[0067] Industrial Applicability The present invention can be used in a power supply system of an electric vehicle.

Claims

1. A power supply system for an electric vehicle, It is characterized in that An electric vehicle having a battery for storing electric power for traveling and an electric device for transmitting electric power between the batteries, and including an electric air conditioner as one of the electric devices, The power supply system of the electric vehicle comprises: a circuit that transfers power between the battery and the electrical device; a switch, which is disposed in the circuit; and a controller that controls the switch to stop power transmission between the battery and the electrical device when a collision of the electric vehicle is detected, When a collision of the electric vehicle is detected, the controller performs a determination process related to air conditioning control of the vehicle cabin, and based on a result of the determination process, controls the switch to transmit power from the battery to the electric air conditioner to drive the electric air conditioner.

2. The power supply system for an electric vehicle according to claim 1, It is characterized in that The determination process includes a process of estimating a temperature change in a vehicle cabin when the electric air conditioner is not driven, and determining whether the estimated temperature after the change is outside a first temperature range.

3. The power supply system for an electric vehicle according to claim 1, It is characterized in that The determination process includes a process of determining a result of a fault diagnosis of the electric air conditioner, a result of a fault diagnosis of the battery, or a result of both fault diagnoses.

4. The power supply system for an electric vehicle according to claim 1, It is characterized in that The power supply system of the electric vehicle is further provided with a discharge switch for releasing the charge remaining in the electric device. The controller detects a collision of the electric vehicle and temporarily drives the electric air conditioner using the charge remaining in the electric device while the charge is discharged by the discharge switch.

5. The power supply system for an electric vehicle according to claim 4, It is characterized in that The judgment process includes a first judgment process and a second judgment process. In the first judgment process, a temperature change in the vehicle cabin when the electric air conditioner is not driven is estimated, and it is determined whether the estimated temperature after the change is outside a first temperature range. In the second judgment process, a result of the fault diagnosis of the electric air conditioner and a result of the fault diagnosis of the battery are determined. When the result of the first judgment processing is outside the first temperature range, the controller temporarily drives the electric air conditioner using the charge remaining in the electrical equipment, and thereafter, when the result of the second judgment processing is normal, drives the electric air conditioner using the power of the battery.

6. The power supply system for an electric vehicle according to claim 1, It is characterized in that The electrical device includes an inverter for driving a driving motor. The circuit includes: a first circuit capable of transmitting power from the battery to the inverter and the electric air conditioner; and a second circuit capable of transmitting power from the battery to the electric air conditioner excluding the inverter. The switch includes: a first switch disposed on a first circuit; a second switch disposed on the second circuit; and a third switch capable of disconnecting the first circuit from the second circuit. When the electric air conditioner is driven by the power of the battery based on a result of the determination process, the controller transmits the power of the battery to the electric air conditioner via the second circuit disconnected from the first circuit.

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