Electric vehicle

Abstract

To provide an electric vehicle capable of performing evacuation travel using an integrated circuit when an abnormality occurs in a microcomputer in a control device of a motor.SOLUTION: An electric vehicle in which a control device of a motor has a microcomputer and an integrated circuit, comprises: a first output unit that outputs a command for gate-shutting off an inverter based on a shutdown command from the microcomputer to the inverter; a second output unit that outputs a command to the inverter independently of the command from the microcomputer; and a command generation unit that generates a shutdown command for the inverter when an abnormality in the microcomputer is detected, and outputs the command to the second output unit. The second output unit outputs the command for gate-shutting off the inverter based on the shutdown command from the command generation unit to the inverter. When an abnormality in the microcomputer is detected, the integrated circuit switches the output unit that outputs commands to the inverter from the first output unit to the second output unit, controls the inverter by commands from the second output unit, and performs evacuation travel.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electric vehicle. [Background technology]

[0002] Patent Document 1 discloses that an electric vehicle equipped with a motor for driving transitions to evacuation driving when an abnormality occurs in the motor control device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-62930 Summary of the Invention [Problem to be solved by the invention]

[0004] In an electric vehicle, the motor control device may include a microcomputer and an integrated circuit. In this case, it is conceivable that a simple evacuation driving function is installed in the integrated circuit, and evacuation driving can be performed by the integrated circuit if an abnormality occurs in the microcomputer. However, if an abnormality occurs in the microcomputer and the command output from the microcomputer to the integrated circuit becomes fixed to a command to shut off the inverter gate, the inverter will be fixed in the gate-shut state, and evacuation driving by the integrated circuit will not be possible.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide an electric vehicle that can perform evacuation driving using an integrated circuit when an abnormality occurs in the microcomputer in the motor control device. [Means for solving the problem]

[0006] The present invention is an electric vehicle comprising a motor, an inverter that drives the motor, and a control device that controls the inverter, wherein the control device has a microcomputer that outputs commands to control the inverter, and an integrated circuit that is communicatively connected to the microcomputer, wherein the integrated circuit has a first output unit that outputs a command to the inverter to gate off the inverter in response to a shut-off command for the inverter input from the microcomputer, a second output unit that outputs a command to the inverter without a command from the microcomputer, and a command generation unit that generates a shut-off command for the inverter and outputs the command to the second output unit when an abnormality of the microcomputer is detected, wherein the second output unit outputs a command to the inverter to gate off the inverter in response to the shut-off command for the inverter input from the command generation unit, and when an abnormality of the microcomputer is detected, the integrated circuit switches the output unit that outputs commands to the inverter from the first output unit to the second output unit, and controls the inverter in response to a command from the second output unit to perform evacuation running. [Effects of the Invention]

[0007] In the present invention, if an abnormality occurs in the microcomputer in the motor control device, the output section that outputs commands to the inverter switches from the first output section to the second output section, so that even if the shut-off command from the microcomputer is fixed, evacuation driving can be performed using the integrated circuit. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram schematically illustrating an electric vehicle according to an embodiment. [Figure 2] FIG. 10 is a diagram for explaining an operation during normal control. [Figure 3] FIG. 10 is a diagram for explaining the operation when the microcomputer is abnormal. [Figure 4] FIG. 10 is a diagram showing a logic circuit for normal driving. [Figure 5] FIG. 10 is a diagram showing a logic circuit for evacuation travel. [Figure 6]FIG. 4 is a sequence diagram showing control when an abnormality occurs in the microcomputer of the MG-ECU. DETAILED DESCRIPTION OF THE INVENTION

[0009] An electric vehicle according to an embodiment of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to the embodiment described below.

[0010] 1 is a diagram illustrating an electric vehicle according to an embodiment. The electric vehicle 1 includes a first motor 2, a second motor 3, a first inverter 4, a second inverter 5, an MG-ECU 10, and a host ECU 20.

[0011] The first motor 2 and the second motor 3 are motor generators that function as an electric motor and a generator. The first motor 2 mainly functions as a generator. The second motor 3 mainly functions as an electric motor. In the electric vehicle 1, the wheels are driven by at least one of the power output from the first motor 2 and the power output from the second motor 3. The first motor 2 and the second motor 3 are connected to different rotating elements of the power split mechanism. The first motor 2 is electrically connected to a first inverter 4. The second motor 3 is electrically connected to a second inverter 5. The first motor 2 is driven by power supplied from the first inverter 4. The second motor 3 is driven by power supplied from the second inverter 5.

[0012] The first inverter 4 is an inverter that drives the first motor 2. The first inverter 4 converts DC power supplied from the battery into AC power and supplies it to the first motor 2. The first inverter 4 is provided between the first motor 2 and the battery. The first inverter 4 is composed of an electric circuit (drive unit) with six switching elements. The six switching elements are arranged to form a U-phase arm, a V-phase arm, and a W-phase arm. A diode is connected in parallel to each switching element in the opposite direction. In the first inverter 4, the three-phase coils of the first motor 2 are connected to each connection point between pairs of switching elements. A boost converter may be provided between the first inverter 4 and the battery. The boost converter boosts the DC power from the battery to a predetermined voltage and supplies it to the first inverter 4. The first inverter 4 converts the DC power supplied from the boost converter into AC power.

[0013] The second inverter 5 is an inverter that drives the second motor 3. The second inverter 5 converts DC power supplied from the battery into AC power and supplies it to the second motor 3. The second inverter 5 is provided between the second motor 3 and the battery. Like the first inverter 4, the second inverter 5 is configured with an electric circuit (drive unit) equipped with six switching elements. In the second inverter 5, the three-phase coils of the second motor 3 are connected to each of the connection points between pairs of switching elements. A boost converter may be provided between the second inverter 5 and the battery. This boost converter is common to both the first inverter 4 and the second inverter 5. The boost converter boosts the DC power from the battery to a predetermined voltage and supplies it to the second inverter 5. The second inverter 5 converts the DC power supplied from the boost converter into AC power. In the following description, the first inverter 4 and the second inverter 5 will be simply referred to as inverters unless they are to be distinguished from each other.

[0014] The MG-ECU 10 is an electronic control device that controls the first inverter 4 and the second inverter 5. The MG-ECU 10 is an inverter control device and functions as a motor control device. In the electric vehicle 1, one MG-ECU 10 controls two motors. The MG-ECU 10 includes a CPU, a storage unit that stores data such as various programs, and a processing unit that performs various calculations to control the motors. The MG-ECU 10 processes signals according to programs pre-stored in a ROM. Signals from various sensors are input to the MG-ECU 10. Examples of signals input to the MG-ECU 10 include a vehicle speed signal from a vehicle speed sensor that detects the vehicle speed of the electric vehicle 1, a resolver signal from an angle sensor that detects the rotation angle of the first motor 2, a resolver signal from an angle sensor that detects the rotation angle of the second motor 3, a current value from a current sensor that detects the current of the first motor 2, and a current value from a current sensor that detects the current of the second motor 3. The MG-ECU 10 then performs various controls based on the signals input from the various sensors.

[0015] The MG-ECU 10 includes a microcomputer 11 and an ASIC (Application Specific Integrated Circuit) 12. The MG-ECU 10 includes one microcomputer 11 and one ASIC 12. The microcomputer 11 and the ASIC 12 are connected to each other so that they can communicate with each other. In the MG-ECU 10, the microcomputer 11 has a calculation function, and the ASIC 12 has a peripheral function. Both the microcomputer 11 and the ASIC 12 function as control units that control the motor.

[0016] The microcomputer 11 is a microcomputer equipped with a CPU, RAM, ROM, and an input / output interface. The microcomputer 11 functions as a control unit that controls the first motor 2 and also functions as a control unit that controls the second motor 3.

[0017] For example, when a resolver signal from an angle sensor of the first motor 2 is input to the MG-ECU 10, the microcomputer 11 performs calculations for motor control, such as calculating the rotation speed of the first motor 2 based on the resolver signal. As a result of the calculations by the microcomputer 11, a command for controlling the first inverter 4 is output from the MG-ECU 10 to the first inverter 4. This command includes a switching control signal for the switching elements of the first inverter 4. The MG-ECU 10 controls the first inverter 4 to control the voltage and current applied to the first motor 2.

[0018] When a resolver signal from the angle sensor of the second motor 3 is input to the MG-ECU 10, the microcomputer 11 performs calculations for motor control, such as calculating the rotation speed of the second motor 3, based on the resolver signal. As a result of the calculations in the microcomputer 11, a command for controlling the second inverter 5 is output from the MG-ECU 10 to the second inverter 5. This command includes a switching control signal for the switching elements of the second inverter 5. The MG-ECU 10 controls the second inverter 5 to control the voltage and current applied to the second motor 3.

[0019] The ASIC 12 is an integrated circuit having a function of causing the electric vehicle 1 to run in an evacuation mode when an abnormality occurs in the microcomputer 11. A program for executing the evacuation mode control is stored in the ASIC 12. The ASIC 12 executes the evacuation mode control when an abnormality occurs in the microcomputer 11. The ASIC 12 functions as an evacuation mode control unit.

[0020] The ASIC 12 stores some or all of the hardware portion of the microcontroller 11 that is specialized for motor control. This hardware portion includes motor angle measurement (RDC), motor current measurement (dedicated ADC), and motor control IP (EMU).

[0021] The host ECU 20 is an electronic control device that controls the electric vehicle 1. Signals from various sensors are input to the host ECU 20. The host ECU 20 executes various controls based on the signals input from the various sensors. The host ECU 20 is connected to the MG-ECU 10 so as to be able to communicate with the MG-ECU 10.

[0022] The host ECU 20 includes a microcomputer 21. The microcomputer 21 is a microcomputer including a CPU, RAM, ROM, and an input / output interface. The microcomputer 21 is connected to the microcomputer 11 and the ASIC 12 so as to be able to communicate with them. The microcomputer 21 outputs various commands to the microcomputer 11 and the ASIC 12.

[0023] In the electric vehicle 1 configured as described above, in a system in which two motors are controlled by a single microcomputer 11, the ASIC 12 is equipped with an emergency driving function, allowing the vehicle to continue driving even if the microcomputer 11 fails. During normal driving, as shown in FIG. 2, the ASIC 12 controls the command output to the inverter drive unit according to a conditional expression for normal driving in response to a shutoff command sdn and a release command rg output from the microcomputer 11 to the ASIC 12 in the MG-ECU 10. In other words, the ASIC 12 has a shutoff command determination function and an emergency driving conditional expression. Furthermore, by switching the control of the command output when an abnormality occurs in the microcomputer 11, it is possible to release the shutoff and control the desired command output.

[0024] As shown in Figures 2 and 3, ASIC 12 includes a normal driving output unit 121, an evacuation driving output unit 122, and a command generation unit 123. ASIC 12 includes normal driving output unit 121 and evacuation driving output unit 122 as output units that output commands to the inverters. Normal driving output unit 121 is a first output unit, and evacuation driving output unit 122 is a second output unit. Note that although Figures 2 and 3 show an operation in which ASIC 12 outputs a shutdown command SDN to second inverter 5, ASIC 12 can also output a shutdown command SDN to first inverter 4.

[0025] The normal driving output unit 121 is an output unit that outputs a shutoff command SDN to the inverter during normal control. During normal control, the normal driving output unit 121 outputs the shutoff command SDN to the inverter in response to a shutoff command sdn and a release command rg input from the microcomputer 11. This shutoff command sdn is a command output from the microcomputer 11 to the ASIC 12 and is a command to shut off the gate of the inverter. This release command rg is a command output from the microcomputer 11 to the ASIC 12 and is a command to release the shutdown of the inverter gate. This shutoff command SDN is a command output from the normal driving output unit 121 (ASIC 12) to the inverter and is a command to shut off the gate of the inverter. As shown in FIG. 2 , when shutting off the gate of the inverter during normal control, the normal driving output unit 121 outputs the shutoff command SDN to the inverter in response to the shutoff command sdn input from the microcomputer 11. When releasing the gate shutdown state of the inverter during normal control, the normal driving output unit 121 releases the output of the shutoff command SDN in response to the release command rg input from the microcomputer 11. During normal control, the evacuation travel output unit 122 and the command generation unit 123 are not used.

[0026] As shown in Fig. 4, the normal driving output unit 121 has a condition expression (logic circuit) for normal driving. In the normal driving logic circuit, a logical sum condition including input of a shutdown command sdn from the microcomputer 11 is set as a condition for outputting the shutdown command SDN. The normal driving output unit 121 is capable of outputting a shutdown command GSDN to the first inverter 4 to shut off the gate of the first inverter 4 during normal control, and outputting a shutdown command MSDN to the second inverter 5 to shut off the gate of the second inverter 5. Note that MCU in Fig. 4 refers to the microcomputer 11, and HV refers to the higher-level ECU 20.

[0027] The evacuation travel output unit 122 is an output unit that outputs a shutoff command SDN to the inverter when an abnormality occurs in the microcomputer 11. During evacuation travel, the evacuation travel output unit 122 outputs the shutoff command SDN to the inverter in response to the shutoff command sdn input from the command generation unit 123 and the release command rg input from the microcomputer 21 of the host ECU 20. This shutoff command sdn is a command output from the command generation unit 123 to the evacuation travel output unit 122 inside the ASIC 12, and is a command to shut off the gate of the inverter. This release command rg is a command output from the microcomputer 21 of the host ECU 20 to the ASIC 12, and is a command to release the shutoff of the gate of the inverter. This shutoff command SDN is a command output from the evacuation travel output unit 122 (ASIC 12) to the inverter, and is a command to shut off the gate of the inverter. 3, when the inverter gate is to be shut off during evacuation traveling, the evacuation traveling output unit 122 outputs a shutoff command SDN to the inverter in response to the shutoff command sdn input from the command generation unit 123. When the inverter gate is to be released from the shutoff state during evacuation traveling, the evacuation traveling output unit 122 releases the output of the shutoff command SDN in response to the release command rg input from the microcomputer 21 of the host ECU 20. During evacuation traveling, the normal traveling output unit 121 is not used.

[0028] As shown in Fig. 5, the evacuation travel output unit 122 has a condition expression (logic circuit) for evacuation travel. In the evacuation travel logic circuit, a logical sum condition including input of the shutdown command sdn from the command generation unit 123 is set as a condition for outputting the shutdown command SDN. The evacuation travel output unit 122 is capable of outputting a shutdown command GSDN to the first inverter 4 to shut off the gate of the first inverter 4 when an abnormality occurs in the microcomputer, and outputting a shutdown command MSDN to the second inverter 5 to shut off the gate of the second inverter 5. Note that ASIC in Fig. 5 refers to the command generation unit 123, and HV refers to the upper ECU 20.

[0029] The command generating unit 123 generates a shutoff command sdn for shutting off the inverter when an abnormality occurs in the microcomputer 11, and outputs the generated shutoff command sdn to the evacuation traveling output unit 122. The command generating unit 123 has a determination function for determining whether to generate the shutoff command sdn. The command generating unit 123 generates the shutoff command sdn in response to a command from the upper ECU 20, not in response to a command from the microcomputer 11. When it is determined that an abnormality has occurred in the microcomputer 11, the command generating unit 123 generates the shutoff command sdn in response to a command (gate operation) input from the microcomputer 21 of the upper ECU 20, and outputs the shutoff command sdn to the evacuation traveling output unit 122.

[0030] Furthermore, when an abnormality occurs in the microcomputer, a reset signal is output from the ASIC 12 to the microcomputer 11. The microcomputer 11 is reset in response to the reset signal input from the ASIC 12. As a result, the microcomputer 11 transitions from an abnormal state to a reset state.

[0031] In the ASIC 12 configured in this manner, when the microcomputer fails, the need for a shutoff command sdn can be determined within the ASIC 12, and output control is switched from that according to the shutoff command sdn input from the microcomputer 11 to that according to the shutoff command sdn generated within the ASIC 12. In other words, when the ASIC 12 detects an abnormality in the microcomputer 11, it switches the output unit that outputs the shutoff command SDN to the inverter from the normal running output unit 121 to the evacuation running output unit 122, and performs evacuation running by controlling the inverter with the shutoff command SDN from the evacuation running output unit 122. Furthermore, during evacuation running by the ASIC 12, the output of the shutoff command SDN can be controlled using a conditional expression that is different from that during normal control.

[0032] 6 is a sequence diagram showing the control when an abnormality occurs in the microcomputer of the MG-ECU 10. The control shown in FIG.

[0033] When an abnormality is detected in the microcomputer 11, the MG-ECU 10 outputs a reset signal from the ASIC 12 to the microcomputer 11 (step S1). In step S1, the ASIC 12 detects the occurrence of an abnormality in the microcomputer 11 and outputs the reset signal to the microcomputer 11.

[0034] The MG-ECU 10 notifies the host ECU 20 via the ASIC 12 of the occurrence of an abnormality in the microcomputer 11 and the reset state of the microcomputer 11 (step S2). In step S2, the ASIC 12 transmits abnormality information indicating that an abnormality has occurred in the microcomputer 11 and that the microcomputer 11 is in a reset state to the host ECU 20.

[0035] When the host ECU 20 receives the abnormality information about the microcomputer 11 from the MG-ECU 10, it recognizes that an abnormality has occurred in the microcomputer 11 and that the microcomputer 11 has been reset (step S3).

[0036] When the host ECU 20 recognizes that an abnormality has occurred in the microcomputer 22 and that the microcomputer 22 has been reset, the host ECU 20 transmits a signal to the ASIC 12 of the MG-ECU 10 requesting that the ASIC 12 switch to evacuation running (step S4). In step S4, the host ECU 20 requests that the ASIC 12 perform evacuation running.

[0037] When the MG-ECU 10 receives a signal from the host ECU 20 requesting a transition to evacuation running by the ASIC 12 while the microcomputer 11 is in a reset state, the MG-ECU 10 switches the output control for outputting the shutoff command SDN to the inverter from the output control during normal control to the output control for evacuation running (step S5). In step S5, the output unit for the shutoff command SDN output from the ASIC 12 to the second inverter 5 is switched from the normal running output unit 121 to the evacuation running output unit 122.

[0038] After transmitting a signal requesting a transition to evacuation travel to the MG-ECU 10, the host ECU 20 transmits a gate operation and release command rg to the ASIC 12 as a command to control the inverter (step S6). In step S6, the microcomputer 21 of the host ECU 20 outputs the gate operation and release command rg to the ASIC 12.

[0039] The MG-ECU 10 controls the command output to the inverter in accordance with the gate operation and the release command rg from the host ECU 20 (step S7). In step S7, the command generation unit 123 generates a shutoff command sdn in accordance with the gate operation input from the microcomputer 21 of the host ECU 20 to the command generation unit 123 of the ASIC 12. Then, the shutoff command sdn generated by the command generation unit 123 is input to the evacuation travel output unit 122. The shutoff command sdn from the command generation unit 123 and the release command rg from the host ECU 20 are input to the evacuation travel output unit 122.

[0040] Then, the MG-ECU 10 starts the evacuation traveling by the ASIC 12 (step S8). In step S8, the evacuation traveling is started by controlling the inverter by the shutoff command SDN output from the evacuation traveling output unit 122 to the inverter, and running the electric vehicle 1. Because this evacuation traveling is the evacuation traveling in response to the microcomputer abnormality, the inverter side controlled by the ASIC 12 operates normally.

[0041] As described above, according to the embodiment, even if the shutdown command sdn from the microcomputer 11 to the ASIC 12 is fixed when an abnormality occurs in the microcomputer 11 of the MG-ECU 10, the output unit for the shutdown command SDN can be switched from the normal running output unit 121 to the evacuation running output unit 122. This allows evacuation running by the ASIC 12 even if the shutdown command sdn from the microcomputer 11 is fixed. As a result, when an abnormality occurs in the microcomputer 11, it is possible to cancel the shutdown command SDN output from the MG-ECU 10 to the inverter, and to control the output of the shutdown command SDN using a desired conditional expression.

[0042] The electrically powered vehicle 1 may be equipped with an engine. That is, the electrically powered vehicle 1 is configured as any one of an electric vehicle (BEV), a hybrid vehicle (HEV), and a plug-in hybrid vehicle (PHEV). Therefore, the host ECU 20 is configured as an integrated ECU, an HV-ECU, or the like.

[0043] Furthermore, although the configuration has been described in which the MG-ECU 10, which includes one microcomputer 11 and one ASIC 12, controls two motors including the first motor 2 and the second motor 3, the number of motors controlled by the MG-ECU 10 is not limited to two. For example, the MG-ECU 10 may be configured to control only one motor, or may be configured to control three motors.

[0044] Furthermore, in a system in which a boost converter is provided between each inverter 4, 5 and the battery, the MG-ECU 10 controls the boost converter. As a result of calculations by the microcomputer 11, a command for controlling the boost converter is output from the MG-ECU 10 to the boost converter. This command includes a switching control signal for the switching element of the boost converter. The MG-ECU 10 controls the voltage and current applied to the first motor 2 by controlling the first inverter 4 and the boost converter. Similarly, the MG-ECU 10 controls the voltage and current applied to the first motor 2 by controlling the second inverter 5 and the boost converter. [Explanation of symbols]

[0045] 1 Electric vehicles 2. First motor 3 Second motor 4. First inverter 5. Second inverter 10 MG-ECU (control unit) 11 Microcomputer 12 ASIC 20 Upper ECU 21 Microcomputer 121 Normal driving output unit (first output unit) 122 Evacuation travel output unit (second output unit) 123 Command generation section

Claims

1. A motor; an inverter that drives the motor; A control device for controlling the inverter; Equipped with The control device is an electric vehicle having a microcomputer that outputs a command for controlling the inverter and an integrated circuit that is communicatively connected to the microcomputer, The integrated circuit comprises: a first output unit that outputs a command to the inverter to shut off a gate of the inverter in response to a shutoff command of the inverter input from the microcomputer; a second output unit that outputs a command to the inverter without being influenced by a command from the microcomputer; a command generating unit that generates a shutoff command for the inverter and outputs the command to the second output unit when an abnormality is detected in the microcomputer; The second output unit outputs a command to the inverter to shut off a gate of the inverter in response to the shutoff command of the inverter input from the command generating unit, When an abnormality in the microcomputer is detected, the integrated circuit switches an output unit that outputs a command to the inverter from the first output unit to the second output unit, and controls the inverter according to a command from the second output unit to perform evacuation running. An electric vehicle characterized by:

2. The second output unit outputs a command to shut off the gate of the inverter under a condition different from that of the first output unit.

2. The electric vehicle according to claim 1 .

3. A host control device connected to the control device so as to be able to communicate with the host control device is further provided. the command generating unit generates a shutoff command for the inverter in response to a command input from the upper control device and outputs the shutoff command to the second output unit; The second output unit controls output of a command to shut off a gate of the inverter based on the shutoff command input from the command generating unit and a release command to release the gate shutoff of the inverter input from the upper control device.

3. The electric vehicle according to claim 1 or 2.

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