Control device for electric vehicles

Abstract

To provide a control device for electric vehicles that can maintain vehicle operation while ensuring safety during operation. [Solution] A control device for an electric vehicle equipped with an HVIL line wired to a high-voltage system that is connected when there is no abnormality in the high-voltage system and open when there is an abnormality in the high-voltage system, wherein when it is detected that the HVIL line is open (S5), if the electric vehicle is stopped (S6), the control device is set to a power cutoff state in which the power supplied to the high-voltage system is cut off (S8), and if the electric vehicle is running (S6), the control device is set to maintain a power supply state in which power is supplied to the high-voltage system (S12).

Description

【Technical Field】 , 【0007】 , 【0001】 The present invention relates to a control device for an electric vehicle. 【Background Art】 【0002】 Conventionally, in order to prevent an operator from being exposed to high voltage, when removing a connector while voltage is applied, a high-voltage interlock loop circuit that automatically cuts off power from a high-voltage power source has been proposed in Patent Document 1. 【0003】 As described above, in the conventional technology, when the opening of the high-voltage interlock loop circuit is detected, there is a possibility of a work mistake such as disassembling the high-voltage system without turning off the ignition switch. Therefore, in order to ensure the safety of the work, the power from the high-voltage power source is cut off. 【Prior Art Documents】 【Patent Documents】 【0004】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 2013-980,56 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0005】 When the opening of the high-voltage interlock loop circuit is detected due to a work mistake, it is necessary to cut off the power from the high-voltage power source in order to ensure safety. When the opening of the high-voltage interlock loop circuit is detected, there is a possibility of a work mistake, but there is also a possibility that the high-voltage interlock loop circuit is disconnected or short-circuited. <000,0029><000,0030><000,0031>Even if the high-voltage interlock loop circuit is opened, it does not affect the running of the vehicle. Therefore, when the opening of the high-voltage interlock loop circuit is detected due to disconnection or short-circuit of the high-voltage interlock loop circuit, it is desirable to maintain the running of the vehicle. <000,0032><000,0033> However, it is electrically impossible to distinguish whether the opening of the high-voltage interlock loop circuit is due to a work error or a break or short circuit in the high-voltage interlock loop circuit. Therefore, conventional technology has the problem of not being able to maintain vehicle operation while ensuring the safety of the work. 【0008】 This invention has been made in view of the above circumstances, and aims to provide a control device for electric vehicles that can maintain the vehicle's movement while ensuring the safety of the work. [Means for solving the problem] 【0009】 The electric vehicle control device according to the present invention is a control device for an electric vehicle provided with a high-voltage system and a high-voltage interlock line wired to the high-voltage system so as to be connected when there is no abnormality in the high-voltage system and open when there is an abnormality in the high-voltage system, and has a configuration comprising a control unit that, when it detects that the high-voltage interlock line is in the open state, puts the electric vehicle into a power cutoff state in which the power supplied to the high-voltage system is cut off if the electric vehicle is stopped, and maintains a power supply state in which power is supplied to the high-voltage system if the electric vehicle is running. [Effects of the Invention] 【0010】 The present invention can provide a control device for electric vehicles that can maintain vehicle operation while ensuring safety during operation. [Brief explanation of the drawing] 【0011】 [Figure 1] Figure 1 is a schematic diagram of a hybrid vehicle equipped with a control device for an electric vehicle according to one embodiment of the present invention. [Figure 2] Figure 2 is a flowchart showing the HVIL control operation of a control device for an electric vehicle according to one embodiment of the present invention. [Figure 3]Figure 3 is a flowchart following Figure 2. [Modes for carrying out the invention] 【0012】 A control device for an electric vehicle according to one embodiment of the present invention is a control device for an electric vehicle that includes a high-voltage system and a high-voltage interlock line wired to the high-voltage system so as to be connected when there is no abnormality in the high-voltage system and open when there is an abnormality in the high-voltage system, and is characterized by having a control unit that, when it detects that the high-voltage interlock line is open, puts the electric vehicle into a power cut-off state where the power supplied to the high-voltage system is cut off if the electric vehicle is stopped, and maintains a power supply state where power is supplied to the high-voltage system if the electric vehicle is running. As a result, the control device for an electric vehicle according to one embodiment of the present invention can maintain the running of the vehicle while ensuring the safety of the work. [Examples] 【0013】 Hereinafter, a hybrid vehicle equipped with a control device for an electric vehicle according to one embodiment of the present invention will be described with reference to the drawings. 【0014】 As shown in Figure 1, the hybrid vehicle 1 is composed of an engine 2, a high-voltage battery 3, a first motor 4 (hereinafter also referred to as "MG1"), a first inverter 5, a second motor 6 (hereinafter also referred to as "MG2"), a second inverter 7, a boost converter 8, drive wheels 9, an air conditioner (hereinafter also referred to as "A / C") 10, a DC-DC converter 11, a low-voltage battery 12, a DC-AC converter 13, and a hybrid controller (hereinafter simply referred to as "HCU") 14. 【0015】 Engine 2 has multiple cylinders. In this embodiment, engine 2 generates power by performing a series of four strokes for each cylinder, consisting of an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. 【0016】 The high-voltage battery 3 is composed of a rechargeable secondary battery, for example, a lithium-ion battery. The high-voltage battery 3 accumulates the electric power generated by MG1 and MG2 and supplies the electric power for driving MG1 and MG2. 【0017】 MG1 is provided so as to be interlocked with the crankshaft of the engine 2. MG1 is connected to the high-voltage battery 3 via the first inverter 5 and the boost converter 8. MG1 has a function of an electric motor that rotates by being supplied with electric power from the high-voltage battery 3 to start the engine 2, and a function of a generator that converts the power generated by the engine 2 into electric power. 【0018】 MG2 is provided so as to be interlocked with the drive wheels 9 via a power transmission member such as a gear mechanism. MG2 is connected to the high-voltage battery 3 via the second inverter 7 and the boost converter 8. 【0019】 MG2 has a function of an electric motor that rotates by being supplied with electric power from the high-voltage battery 3 and MG1 to rotate the drive wheels 9, and a function of a generator that converts the rotational force of the drive wheels 9 into electric power. 【0020】 The boost converter 8 is provided between the high-voltage battery 3 and the first inverter 5 and the second inverter 7, boosts the voltage of the electric power supplied from the high-voltage battery 3 to the first inverter 5 and the second inverter 7, and降压 the voltage of the electric power supplied from the first inverter 5 and the second inverter 7 to the high-voltage battery 3. 【0021】 A / C 10 operates by the electric power supplied from the high-voltage battery 3 and adjusts the temperature in the vehicle interior. The DCDC converter 11降压 the electric power stored in the high-voltage battery 3 and supplies it to the low-voltage battery 12. 【0022】 The low-voltage battery 12 stores the electric power supplied to electrical loads such as headlights, lamps, meters provided on the instrument panel, and a car navigation system. 【0023】 The DCAC converter 13 converts the power stored in the high-voltage battery 3 from DC power to AC power, and supplies the AC power to an electrical load operating on AC, for example, connected to a power outlet provided in the hybrid vehicle 1. 【0024】 The HCU 14 is composed of a computer unit including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory for storing backup data and the like, an input port, and an output port. 【0025】 In the ROM of this computer unit, a program for making the computer unit function as the HCU 14 is stored together with various constants and various maps. That is, when the CPU executes the program stored in the ROM using the RAM as a working area, this computer unit functions as the HCU 14 in this embodiment. 【0026】 Various sensors including an ignition switch (hereinafter, also simply referred to as "IG") 21, a vehicle speed sensor 22 for detecting the vehicle speed, and a high-voltage interlock line (hereinafter, also simply referred to as "HVIL line") 23 are connected to the input port of the HCU 14. 【0027】 The HVIL line 23 is wired to the high-voltage system so as to be in a connected state when there is no abnormality in the high-voltage system and in an open state when there is an abnormality in the high-voltage system. Specifically, the HVIL line 23 is connected to the ground via a certain load after passing through each part of the high-voltage system in a state where the input port side of the HCU 14 is pulled up to a low voltage (for example, 5V). 【0028】 In this embodiment, the HCU14 determines that the HVIL line 23 is open if the voltage of the input port to which the HVIL line 23 is connected (hereinafter also simply referred to as the "HVIL line voltage") is within a first range of 4.89V to 5V. 【0029】 If the HVIL line voltage is within the first range, there is a possibility that the HVIL line 23 is in a short circuit. However, the HCU 14 performs the same processing as if the HVIL line 23 were in an open circuit when the HVIL line 23 is in a short circuit, and therefore determines that the HVIL line 23 is in an open circuit. 【0030】 HCU14 determines that HVIL line 23 is connected if the HVIL line voltage is within the second range of 2.21V to 3.09V. HCU14 determines that HVIL line 23 is ground faulted if the HVIL line voltage is within the third range of 0V to 1.02V. 【0031】 The HVIL line voltage will be within one of three ranges, from the first to the third, depending on the state of the HVIL line 23. If the HVIL line voltage is not within any of the three ranges, the HCU 14 determines that the HVIL line voltage is not changing, as this may indicate that the HVIL line voltage is in the process of changing. 【0032】 In this embodiment, the high-voltage system is comprised of the following high-voltage components: a first inverter 5, a second inverter 7, a boost converter 8, an A / C 10, a DC-DC converter 11, and a DC-AC converter 13. 【0033】 The HVIL line 23 is provided on the connectors (hereinafter also simply referred to as "high-voltage connectors") that connect the high-voltage equipment constituting the high-voltage system. In other words, the HVIL line 23 is wired to be connected when all high-voltage connectors are properly connected, and to be open when any of the high-voltage connectors are not properly connected. 【0034】 The output ports of the HCU14 are connected to various control devices, including the first inverter 5, the second inverter 7, the boost converter 8, the A / C 10, the injector 31 that supplies fuel to the engine 2, the spark plug 32 that ignites in the combustion chamber of the engine 2, the power switch 33, and the warning light 34. 【0035】 Furthermore, if engine 2 is composed of an engine that does not require a spark plug, such as a diesel engine, the spark plug 32 is omitted from the configuration of hybrid vehicle 1. 【0036】 The power switch 33 switches the power state of the high-voltage system between a power supply state in which power is supplied to the high-voltage system from the high-voltage battery 3, and a power cut-off state in which the power supplied to the high-voltage system from the high-voltage battery 3 is cut off. 【0037】 The HCU14 controls various control targets connected to the output ports based on information obtained from various sensors connected to the input ports. When the HCU14 detects that the HVIL line 23 is open, it functions as a control unit 40 that shuts off the power supply if the hybrid vehicle 1 is stationary, and maintains the power supply state if the hybrid vehicle 1 is running. 【0038】 Specifically, if the HCU14 detects that the HVIL line 23 is open based on the HVIL line voltage, it controls the power switch 33 to cut off power if the hybrid vehicle 1 is stationary, and controls the power switch 33 to maintain power supply if the hybrid vehicle 1 is in motion. The HCU14 determines whether the hybrid vehicle 1 is stationary or not based on the detection result of the vehicle speed sensor 22. 【0039】 If the HCU14 detects that the HVIL line 23 is open and maintains the power supply state, it controls the system to maintain the power supply state and start the engine 2 when the next ignition cycle begins. 【0040】 In other words, when the HCU14 detects that the HVIL line 23 is open, it maintains the power supply state and turns off IG21. Subsequently, when IG21 is turned on, it maintains the power supply state and controls the engine 2 to start. 【0041】 When HCU14 controls the engine 2 to start, it controls the first inverter 5 to drive MG1, thereby rotating the crankshaft of the engine 2 and initiating fuel supply by the injector 31 and ignition by the spark plug 32 until the engine 2 is running autonomously. 【0042】 If the HCU14 detects that the HVIL line 23 is open, it controls the system to start the engine 2 if the hybrid vehicle 1 is in motion and the engine 2 is stopped. 【0043】 Therefore, if the HCU14 detects that the HVIL line 23 is open, it controls the system to maintain the power supply state if the hybrid vehicle 1 is running, and to start the engine 2 if the engine 2 is stopped. 【0044】 If the HCU14 detects that the HVIL line 23 has a ground fault, it controls the system to maintain the power supply state and start the engine 2 if it is stopped, regardless of whether the hybrid vehicle 1 is in motion or not. 【0045】 The HVIL control operation of the HCU14 configured as described above will be explained with reference to Figures 2 and 3. The HVIL control operation described below will be repeatedly executed throughout the period that the HCU14 is operating. 【0046】 First, in S1 shown in Figure 2, the HCU14 determines whether or not IG21 has been switched from off to on. If in S1 it is determined that IG21 has been switched from off to on, the HCU14 executes the process in S2. If in S1 it is determined that IG21 has not been switched from off to on, the HCU14 executes the process in S4. 【0047】 In S2, the HCU14 determines whether the HVIL open flag is on, which indicates that the HVIL line 23 is open while the hybrid vehicle 1 is in motion. 【0048】 In S2, if it is determined that the HVIL release flag is on, HCU14 executes the process in S3. In S2, if it is determined that the HVIL release flag is not on, HCU14 terminates the HVIL control operation. 【0049】 In S3, the HCU14 illuminates the warning light 34, maintains the power supply, and starts the engine 2. After completing the process in S3, the HCU14 terminates the HVIL control operation. 【0050】 In S4 shown in Figure 3, the HCU14 determines whether IG21 is on or off. If it determines in S4 that IG21 is on, the HCU14 executes the process in S5. If it determines in S4 that IG21 is not on, the HCU14 terminates the HVIL control operation. 【0051】 In S5, HCU14 determines whether the HVIL line 23 is open or not. If HCU14 determines in S5 that the HVIL line 23 is open, HCU14 executes the process in S6. If HCU14 determines in S5 that the HVIL line 23 is not open, HCU14 executes the process in S9. 【0052】 In S6, the HCU14 determines whether or not the hybrid vehicle 1 is stationary. If the HCU14 determines in S6 that the hybrid vehicle 1 is stationary, it executes the process in S7. If the HCU14 determines in S6 that the hybrid vehicle 1 is not stationary, that is, that the hybrid vehicle 1 is in motion, it executes the process in S11. 【0053】 In S7, HCU14 determines whether the HVIL release flag is off or not. If HCU14 determines in S7 that the HVIL release flag is off, HCU14 executes the process in S8. If HCU14 determines in S7 that the HVIL release flag is not off, HCU14 executes the process in S12. 【0054】 In S8, HCU14 illuminates the warning light 34, cuts off power, and stops engine 2. After executing the process in S8, HCU14 terminates the HVIL control operation. In S9, HCU14 sets the HVIL release flag to off. After executing the process in S9, HCU14 executes the process in S10. 【0055】 In S10, the HCU14 determines whether or not the HVIL line 23 is ground faulted. If the HCU14 determines in S10 that the HVIL line 23 is ground faulted, it executes the process in S12. If the HCU14 determines in S10 that the HVIL line 23 is not ground faulted, it terminates the HVIL control operation. 【0056】 In S11, HCU14 sets the HVIL release flag to ON. After executing the process in S11, HCU14 executes the process in S12. In S12, HCU14 illuminates the warning light 34 and maintains the power supply state. After executing the process in S12, HCU14 executes the process in S13. 【0057】 In S13, HCU14 determines whether engine 2 is stopped or not. If HCU14 determines that engine 2 is stopped in S13, it executes the process in S14. If HCU14 determines that engine 2 is not stopped in S13, it terminates the HVIL control operation. In S14, HCU14 starts engine 2. After executing the process in S14, HCU14 terminates the HVIL control operation. 【0058】 As described above, the electric vehicle control device according to this embodiment, when it detects that the HVIL line 23 is open, controls the device to shut off power if the hybrid vehicle 1 is stopped, and to maintain power supply if the hybrid vehicle 1 is running. This ensures safety during operation and allows the hybrid vehicle 1 to continue running. 【0059】 Furthermore, if the control device for the electric vehicle according to this embodiment detects that the HVIL line 23 is open and maintains the power supply state, it can maintain the power supply state when the next ignition cycle starts, and thus allow the hybrid vehicle 1 to run in the next ignition cycle as well. 【0060】 Furthermore, the control device for the electric vehicle according to this embodiment detects that the HVIL line 23 is open, and if the hybrid vehicle 1 is running and the engine 2 is stopped, it controls the system to start the engine 2, thereby notifying the system of the abnormal condition through sound and vibration emitted from the engine 2. 【0061】 Furthermore, the control device for the electric vehicle according to this embodiment, when it detects that the HVIL line 23 is open and maintains the power supply state, controls the engine 2 to start when the next ignition cycle begins, so that it can notify the user of an abnormal condition through sound and vibration emitted from the engine 2. 【0062】 Furthermore, the control device for the electric vehicle according to this embodiment detects that the HVIL line 23 has ground fault, and if the engine 2 is stopped, it controls the engine 2 to start, so that the abnormal condition can be notified by sound and vibration emitted from the engine 2. 【0063】 Furthermore, if the control device for the electric vehicle according to this embodiment detects that the HVIL line 23 is open, and the hybrid vehicle 1 is stationary, it will illuminate the warning light 34 and stop the engine 2, thereby informing the driver or service personnel that an abnormal condition is occurring. 【0064】 Furthermore, the control device for the electric vehicle according to this embodiment, when it detects that the HVIL line 23 is open, will illuminate the warning light 34 if the hybrid vehicle 1 is in motion, and will start the engine 2 if the engine 2 is stopped, thereby informing the driver of the abnormal condition and encouraging them to bring the hybrid vehicle 1 to a dealer as soon as possible. 【0065】 Furthermore, the control device for the electric vehicle according to this embodiment, when it detects that the HVIL line 23 is open, illuminates the warning light 34 if the hybrid vehicle 1 is running, and starts the engine 2 if the engine 2 is stopped. This notifies the service technician that power is being supplied and prevents work errors such as disassembling the high-voltage system without turning off the IG21. 【0066】 Furthermore, the control device for the electric vehicle according to this embodiment will illuminate the warning light 34 and start the engine 2 if the engine 2 is stopped if it detects that the HVIL line 23 has ground fault, thereby informing the driver of the abnormal condition and encouraging them to bring the hybrid vehicle 1 to a dealer as soon as possible. 【0067】 Furthermore, the control device for the electric vehicle according to this embodiment, when it detects that the HVIL line 23 has ground fault, will start the engine 2 if the engine 2 is stopped, thereby informing the service technician that power is being supplied and preventing work errors such as disassembling the high-voltage system without turning off the IG21. 【0068】 In this embodiment, the HVIL line 23 was described in an example where it is provided in a high-voltage connector. Thus, the HVIL line 23 only needs to be provided to detect abnormalities in the high-voltage system. 【0069】 For example, the HVIL line 23 may be wired to a case housing one or more high-voltage devices, and may be wired to be connected when the case is closed and open when the case is opened. 【0070】 Furthermore, in this embodiment, an example was described in which the high-voltage system is composed of a first inverter 5, a second inverter 7, a boost converter 8, an A / C 10, a DC-DC converter 11, and a DC-AC converter 13. 【0071】 In contrast, the high-voltage system may consist of one or more high-voltage devices from among the first inverter 5, the second inverter 7, the boost converter 8, the A / C 10, the DC-DC converter 11, and the DC-AC converter 13. Furthermore, the high-voltage system may also include other high-voltage devices such as MG1 and MG2. 【0072】 Although embodiments of the present invention have been disclosed above, it is clear that modifications can be made to these embodiments without departing from the scope of the present invention. The embodiments of the present invention are disclosed on the premise that equivalents with such modifications are included in the invention described in the claims. [Explanation of symbols] 【0073】 1. Hybrid vehicles (electric vehicles) 2 engines 5. First Inverter (High Voltage System) 7. Second Inverter (High Voltage System) 8. Boost converter (high voltage system) 10 A / C (High Voltage System) 11. DC-DC converter (high voltage system) 13. DC-AC Converter (High Voltage System) 23 HVIL line (High Voltage Interlock Line) 40 Control Unit

Claims

[Claim 1] High-voltage systems and, A control device for an electric vehicle, comprising: a high-voltage interlock line wired to the high-voltage system such that it is connected when there is no abnormality in the high-voltage system and is open when there is an abnormality in the high-voltage system; When it is detected that the high-voltage interlock line is in the open state, If the electric vehicle is stopped, the power supplied to the high-voltage system is cut off, thus creating a power cutoff state. A control device for an electric vehicle, characterized by comprising a control unit that controls the electric vehicle to maintain a power supply state in which power is supplied to the high-voltage system when the electric vehicle is in motion. [Claim 2] The control unit, If the power supply state is maintained by detecting that the high-voltage interlock line is in the open state, The control device for an electric vehicle according to claim 1, characterized in that it controls the device to maintain the power supply state when the next ignition cycle is started. [Claim 3] The aforementioned electric vehicle is equipped with an engine, The control unit, When it is detected that the high-voltage interlock line is in the open state, The control device for an electric vehicle according to claim 1, characterized in that it controls the electric vehicle to start the engine if the electric vehicle is in motion and the engine is stopped. [Claim 4] The control unit, If the power supply state is maintained by detecting that the high-voltage interlock line is in the open state, The control device for an electric vehicle according to claim 3, characterized in that it controls the engine to start when the next ignition cycle is initiated. [Claim 5] The aforementioned electric vehicle is equipped with an engine, The control unit, The control device for an electric vehicle according to claim 1, characterized in that, when a ground fault is detected in the high-voltage interlock line, the device controls the engine to start if the engine is stopped.

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