JP2020150649A - Electric vehicle - Google Patents

Abstract

To suppress the overheating of an electric motor and a drive circuit caused by the repeated occurrence of current concentration in the same phase of the electric motor, while making starting performance on an uphill road excellent.SOLUTION: When there occurs a current concentration state in which a current is concentrated in a specific one phase of the phases of a motor for driving drive wheels, a control device of an electric vehicle executes torque restriction for restricting torque output from the motor. Then, the control device cancels the execution of the torque restriction when, during the execution of the torque restriction, there is satisfied any of: a first condition that torque Tm2 output from the motor is less than prescribed torque Tref; a second condition that a rotation number Nm2 of the motor is equal to or greater than a prescribed rotation number Nref; and a third condition that the current concentration state is eliminated, and that a road surface slope S is equal to or greater than a prescribed slope Sref.SELECTED DRAWING: Figure 2

Description

The present invention relates to an electric vehicle.

Conventionally, as an electric vehicle of this type, it has been proposed to limit the output torque output from the motor when a motor lock state occurs in which the motor stops rotating while the motor is energized while traveling on an uphill road. For example, see Patent Document 1). In this electric vehicle, when the output torque is limited by the occurrence of the motor lock state, it is determined that the vehicle has slipped down due to the limitation of the output torque, and when it is determined that the motor has released the motor lock state, Release the output torque limit. As a result, when a motor lock state occurs while traveling on an uphill road, the vehicle slides down due to torque limitation, thereby eliminating the motor lock state and preventing overheating of the motor and the inverter.

Japanese Unexamined Patent Publication No. 2013-172626

By the way, the scene where the motor lock state occurs is not limited to the running on the uphill road, and there are various scenes. As described in Patent Document 1, a current concentration state in which the current is concentrated in a specific phase of the motor by balancing the output torque of the motor and the force acting in the downward direction due to the weight of the vehicle while traveling on an uphill road. When (motor lock state) occurs, the torque limit causes the vehicle to slide down, so that the phase energized by the rolling of the drive wheels changes, and the current concentration state is eliminated. Therefore, even if the execution of the torque limitation is canceled immediately when the current concentration state is resolved, there is no possibility that the current concentration state will be repeated. On the other hand, when a current concentration state occurs when the drive wheels are locked by fitting into a rut or the like, the drive shaft between the motor and the drive wheels is twisted due to the lock of the drive wheels. As the twist is relaxed by the torque limitation, the energized phase changes and the current concentration state is eliminated. Therefore, if the execution of torque limitation is released while the drive wheels are locked, the drive shaft is repeatedly twisted, and as a result, the current concentration state is repeatedly generated in the same phase as the phase in which the current concentration state was previously generated in a short time. However, there is a risk of overheating of the motor and its drive circuit.

The main object of the electric vehicle of the present invention is to suppress overheating of the electric motor and the drive circuit caused by repeated occurrence of current concentration in the same phase of the electric motor while improving the starting performance on an uphill road.

The electric vehicle of the present invention has adopted the following means in order to achieve the above-mentioned main object.

The electric vehicle of the present invention
An electric vehicle including an electric motor for driving a drive wheel and a control device for controlling the electric motor.
The control device executes a torque limit that limits the torque output from the motor when a current concentration state in which the current concentrates in a specific phase of each phase of the motor occurs, and executes the torque limit. The condition that the torque output from the electric motor is less than the predetermined torque, the condition that the current concentration state is eliminated, and the slope of the road surface on which the electric vehicle is traveling is equal to or more than the predetermined slope. When any of the above is satisfied, the execution of the torque limit is released.
The gist is that.

In the electric vehicle of the present invention, torque limiting is executed to limit the torque output from the electric motor when a current concentration state occurs in which the current is concentrated in a specific phase of each phase of the electric motor that drives the drive wheels. .. Then, while the torque limit is being executed, the condition that the torque output from the electric motor is less than the predetermined torque, the current concentration state is eliminated, and the slope of the road surface on which the electric vehicle is traveling is equal to or higher than the predetermined slope. When any of the conditions is satisfied, the execution of the torque limit is released. That is, when the current concentration state occurs and the torque limitation is executed, even if the current concentration state is resolved, the execution of the torque limitation is not immediately canceled unless the slope of the road surface is equal to or higher than the predetermined gradient. As a result, when a current concentration state occurs while driving on an uphill road, the slope of the road surface is equal to or higher than the predetermined slope. Therefore, when the current concentration state is resolved due to the vehicle sliding down due to the torque limit, the torque limit is immediately applied. Execution is canceled. On the other hand, when a current concentration state occurs with the drive wheels locked, for example, on a flat road, the slope of the road surface is less than a predetermined slope, so that the twist of the shaft is eliminated by the torque limitation and the current concentration state is temporarily changed. Even if it is resolved, the torque limit will not be released immediately. While improving the starting performance on an uphill road, it is possible to suppress overheating of the electric motor and the drive circuit caused by repeated current concentration in the same phase of the electric motor due to locking of the drive wheels and the like.

In such an electric vehicle of the present invention, as one of the conditions for releasing the execution of the torque limitation, a condition that the rotation speed of the electric motor is equal to or higher than a predetermined rotation speed may be included. That is, the condition that the torque output from the electric motor is less than the predetermined torque (first condition), the condition that the rotation speed of the electric motor is equal to or more than the predetermined rotation speed (second condition), and the current concentration state are eliminated and the electric vehicle is used. When any of the conditions (third condition) that the slope of the road surface on which the vehicle is traveling is equal to or higher than a predetermined slope is satisfied, the execution of the torque limitation may be released.

It is a block diagram which shows the outline of the structure of the electric vehicle 20 as one Example of this invention. It is a flowchart which shows an example of the torque limit release processing executed by HVECU 70. It is explanatory drawing which shows the state of the release of the torque limitation in the comparative example when the current concentration state occurs in the motor at the time of starting on a slope and the torque limitation is executed. It is explanatory drawing which shows the state of the release of the torque limitation in the comparative example in the case where the current concentration state is generated in the motor by the lock of a drive wheel, and the torque limitation is executed. It is explanatory drawing which shows the state of the release of the torque limit in the Example when the current concentration state is generated in the motor by the lock of a drive wheel, and the torque limit is executed. It is a block diagram which shows the outline of the structure of the electric vehicle 120 of the modification.

Next, a mode for carrying out the present invention will be described with reference to Examples.

FIG. 1 is a configuration diagram showing an outline of the configuration of an electric vehicle 20 as an embodiment of the present invention. As shown in the figure, the electric vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50, and an electronic control unit for a hybrid (hereinafter referred to as "HVECU"). It is configured as a hybrid vehicle equipped with 70.

The engine 22 is configured as an internal combustion engine that outputs power using gasoline, light oil, or the like as fuel. The engine 22 is operated and controlled by an electronic control unit for an engine (hereinafter, referred to as "engine ECU") 24.

Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. .. Signals from various sensors required to control the operation of the engine 22, for example, a crank angle θcr from the crank position sensor 23 that detects the rotational position of the crankshaft 26 of the engine 22 and the like are input to the engine ECU 24 from the input port. Has been done. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 via the output port. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 23.

The planetary gear 30 is configured as a single pinion type planetary gear mechanism. The rotor of the motor MG1 is connected to the sun gear of the planetary gear 30. A drive shaft 36 connected to the drive wheels 39a and 39b via a differential gear 38 is connected to the ring gear of the planetary gear 30. The crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30.

The motor MG1 is configured as, for example, a synchronous motor generator, and as described above, the rotor is connected to the sun gear of the planetary gear 30. The motor MG2 is configured as, for example, a synchronous generator motor, and a rotor is connected to a drive shaft 36. The inverters 41 and 42 are connected to the battery 50 via the power line 54. The motors MG1 and MG2 are rotationally driven by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by an electronic control unit for a motor (hereinafter referred to as "motor ECU") 40.

Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. .. As shown in FIG. 1, signals from various sensors necessary for driving and controlling the motors MG1 and MG2 are input to the motor ECU 40 via the input port. The signals input to the motor ECU 40 include, for example, the rotation positions θm1 and θm2 from the rotation position detection sensors 43 and 44 that detect the rotation position of the rotors of the motors MG1 and MG2, and the U-phase and V of the motors MG1 and MG2. Examples thereof include phase currents Iu1, Iv1, Iu2, and Iv2 from current sensors 45u, 45v, 46u, and 46v that detect currents flowing in the phase. Various control signals for driving and controlling the motors MG1 and MG2, for example, switching control signals to the switching elements of the inverters 41 and 42, are output from the motor ECU 40 via the output port. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 calculates the rotation speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotation positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from the rotation position detection sensors 43 and 44. Further, the motor ECU 40 calculates the phase currents Iw1 and Iw2 flowing in the W phase based on the U-phase and V-phase phase currents Iu1, Iv1, Iu2 and Iv2 from the current sensors 45u, 45v, 46u and 46v.

The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery. The battery 50 is managed by a battery electronic control unit (hereinafter, referred to as “battery ECU”) 52.

Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. .. Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via the input port. The signals input to the battery ECU 52 include, for example, the battery voltage Vb from the voltage sensor 51a attached between the terminals of the battery 50, the battery current Ib from the current sensor 51b attached to the output terminal of the battery 50, and the battery. The battery temperature Tb from the temperature sensor 51c attached to the 50 can be mentioned. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the storage ratio SOC based on the integrated value of the battery current Ib from the current sensor 51b. The storage ratio SOC is the ratio of the capacity of electric power that can be discharged from the battery 50 to the total capacity of the battery 50. Further, the battery ECU 52 calculates the input / output restriction Win and Wout based on the calculated storage ratio SOC and the battery temperature Tb from the temperature sensor 51c. The input / output restrictions Win and Wout are the maximum allowable powers that may charge and discharge the battery 50.

Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. Signals from various sensors are input to the HVECU 70 via input ports. Examples of the signal input to the HVECU 70 include an ignition signal from the ignition switch 80 and a shift position SP from the shift position sensor 82 that detects the operating position of the shift lever 81. Further, the accelerator opening degree Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83 and the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85 can also be mentioned. Further, the vehicle speed V from the vehicle speed sensor 88 and the road surface gradient S from the gradient sensor 89 can also be mentioned. As the gradient sensor 89, for example, a G sensor (acceleration sensor that detects anteroposterior acceleration) can be used. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via a communication port.

In the vehicle 20 of the embodiment configured in this way, the vehicle 20 travels in a hybrid traveling (HV traveling) or in an electric traveling (EV traveling). In HV driving, the vehicle travels with the operation of the engine 22. In EV driving, the engine 22 is stopped and the vehicle travels.

In HV running, the HVECU 70 first sets the required torque Tr * required for running based on the accelerator opening Acc and the vehicle speed V, and the rotation speed Nr (for example, the motor) of the drive shaft 36 is set to the set required torque Tr *. The running power Pdrv * required for running is calculated by multiplying the number of revolutions of MG2 (Nm2, etc.). Then, the required power Pe * required for the vehicle is set by subtracting the charge / discharge required power Pb * of the battery 50 (a positive value when discharging from the battery 50) from the traveling power Pdrv *, and the required power Pe * is set. The target rotation speed Ne *, target torque Te *, and motor of the engine 22 are output from the engine 22 and the required torque Tr * is output to the drive shaft 36 within the range of the input / output limits Win and Wout of the battery 50. Set the torque commands Tm1 * and Tm2 * of MG1 and MG2. Then, the target rotation speed Ne * and the target torque Te * of the engine 22 are transmitted to the engine ECU 24, and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU40. When the engine ECU 24 receives the target rotation speed Ne * and the target torque Te * of the engine 22, the intake air of the engine 22 is operated so that the engine 22 is operated based on the received target rotation speed Ne * and the target torque Te *. Performs quantity control, fuel injection control, ignition control, etc. When the motor ECU 40 receives the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2, the motor ECU 40 controls the switching of the switching elements of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. .. During this HV running, when the stopping condition of the engine 22 is satisfied, such as when the required power Pe * reaches the stop threshold value Pstop or less, the operation of the engine 22 is stopped and the EV running is started.

At the time of EV traveling, the HVECU 70 first sets the required torque Tr * in the same manner as in the HV traveling. Subsequently, a value 0 is set in the torque command Tm1 * of the motor MG1, and the torque command Tm2 of the motor MG2 is output so that the required torque Tr * is output to the drive shaft 36 within the range of the input / output restrictions Win and Wout of the battery 50. Set *. Then, the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40. When the motor ECU 40 receives the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2, the motor ECU 40 controls the switching of the switching elements of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. .. During this EV driving, when the starting conditions of the engine 22 are satisfied, such as when the required power Pe * calculated in the same manner as in the HV driving reaches the starting threshold Pstart larger than the stopping threshold Pstop, the engine 22 Is started to shift to HV driving.

Next, the operation of the electric vehicle 20 of the embodiment configured in this way, in particular, the torque output from the motor MG2 when starting on a slope and the force acting in the downward direction due to the weight of the vehicle are balanced, or due to ruts or the like. The operation when the drive wheels 39a and 39b are locked and a current concentration state in which the current is concentrated in one specific phase of each phase of the motor MG2 occurs will be described. FIG. 2 is a flowchart showing an example of the torque limit release process executed by the HVECU 70.

When the torque limit release process is executed, the HVECU 70 first determines whether or not the current concentration flag F is on (step S100). Here, the current concentration flag F is a flag that is turned on when it is determined that the current concentration state has occurred, and is turned off when it is determined that the current concentration state has been resolved. Whether or not a current concentration state has occurred is determined based on the U-phase and V-phase phase currents Iu2 and Iv2 of the motor MG2 and the U-phase and V-phase phase currents Iu2 and Iv2 from the current sensors 46u and 46v. It is performed by determining whether or not one of the calculated W-phase phase currents Iw2 is equal to or greater than the first threshold value and the rest is approximately 0. Further, the determination as to whether or not the current concentration state has been resolved is performed by determining whether or not the phase current that is equal to or greater than the first threshold value is less than the second threshold value that is lower than the first threshold value. If it is determined that the current concentration flag F is not on but off, this process ends as it is.

On the other hand, when it is determined that the current concentration flag F is on, the torque limit of the motor MG2 is executed (started) (step S110). For the torque limit, for example, the upper limit torque is set so that it gradually decreases with the passage of time at a predetermined rate of change from the torque of the motor MG2 currently being output, and the required torque Tr * is within the set upper limit torque range. This is done by setting the torque command Tm2 * of the motor MG2 so that it is output to the drive shaft 36. That is, the torque limit is performed by gradually strengthening the limit with the passage of time.

When the torque limit is executed, next, the rotation speed Nm2 of the motor MG2, the torque Tm2 of the motor MG2, and the road surface gradient S from the gradient sensor 89 are input (step S120). The rotation speed Nm2 of the motor MG2 is calculated based on the rotation position θm2 of the motor MG2 detected by the rotation position detection sensor 44, and is input from the motor ECU 40 by communication. Further, the torque Tm2 of the motor MG2 is assumed to input the torque command Tm2 * used for the drive control of the motor MG2 as the torque actually output from the motor MG2. Then, whether or not the first condition that the torque Tm2 of the motor MG2 is less than the predetermined torque Tref is satisfied (step S130), and the second condition that the rotation speed Nm2 of the motor MG2 is equal to or more than the predetermined rotation speed Nref are satisfied. Whether or not (step S140) and whether or not the third condition that the current concentration flag F is off and the road surface gradient S is equal to or higher than the predetermined gradient Sref is satisfied (steps S150 and S160) are determined. Here, the predetermined torque Tref is set to a torque that does not overheat the motor MG2 and the inverter 42 even if a current concentration state occurs. The predetermined rotation speed Nref is a threshold value for determining whether or not the motor MG2 is rotating to the extent that the energized phase changes. The predetermined gradient Sref is defined as a road surface gradient to which the vehicle slides down even if a slight torque (for example, creep torque) is output from the drive shaft 36.

If it is determined that none of the first to third conditions is satisfied, the process returns to step S120 until it is determined that any of the first to third conditions is satisfied, the rotation speed Nm2, the torque Tm2, and the road surface gradient S. Is input to repeat the determination that the condition is satisfied. If it is determined that any of the first to third conditions is satisfied in the process of repeating this determination, the execution of the torque limit is canceled (step S170), and this process is terminated. To release the torque limit, for example, set the upper limit torque so that it gradually increases with the passage of time at a predetermined rate of change from the torque of the motor MG2 currently being output, and the required torque Tr is set within the set upper limit torque range. This is performed by setting the torque command Tm2 * of the motor MG2 so that * is output to the drive shaft 36. That is, the torque limit is performed by gradually relaxing the limit with the passage of time.

FIG. 3 is an explanatory diagram showing a state in which the torque limit is released in a comparative example in which a current concentration state is generated in the motor and torque limit is executed when starting on a slope, and FIG. 4 is an explanatory view of the drive wheels. It is explanatory drawing which shows the state of the release of the torque limit in the comparative example when the current concentration state is generated in the motor by the lock and the torque limit is executed. FIG. 5 is an explanatory diagram showing a state in which the torque limit is released in the embodiment when a current concentration state is generated in the motor due to the lock of the drive wheels and the torque limit is executed. Here, in the comparative example, as the third condition, the torque limit is released when the current concentration flag F changes from on to off regardless of the road surface gradient S. When starting on a slope, the start of the torque output to the drive shaft 36 is delayed as the engine 22 starts, and the torque output to the drive shaft 36 and the force acting in the downward direction due to the weight of the vehicle are balanced. In this case, current concentration occurs in a specific phase of the motor MG2. As shown in FIG. 3, when current concentration occurs in the motor MG2 and the current concentration flag F changes from off to on, torque limitation is executed (see time t11). In the comparative example, the current concentration is eliminated by causing the vehicle to slide down due to the torque limitation, and when the current concentration flag F is turned from on to off, the execution of the torque limitation is immediately canceled (see time t12). As a result, it is possible to improve the startability when starting on a slope while suppressing overheating of the motor MG2 and the inverter 42 due to current concentration. On the other hand, when the drive wheels 39a and 39b are locked, current concentration occurs in a specific phase of the motor MG2, and torque limitation is similarly executed (see time t21). In the comparative example, as described above, when the current concentration is eliminated and the current concentration flag F changes from on to off, the execution of the torque limit is immediately released (see time t22). When current concentration occurs in the motor MG2 with the drive wheels 39a and 39b locked, the drive shaft 36 between the motor MG2 and the drive wheels 39a and 39b is twisted. Therefore, the twist is caused by the torque limitation. Is relaxed, the phase to be energized changes, and the current concentration is eliminated. Therefore, if the execution of the torque limitation is released while the drive wheels 39a and 39b are locked, the drive shaft 36 is repeatedly twisted, and as a result, the current concentration state is in the same phase as the phase in which the current concentration state occurred last time. Is repeatedly generated in a short period of time, causing overheating of the motor MG2 and the inverter 42.

On the other hand, in the embodiment, as the third condition, the torque limit is released when the current concentration flag F changes from on to off and the road surface gradient S is equal to or higher than the predetermined gradient Sref. As a result, when current concentration occurs in the motor MG2 when starting on a slope, the road surface gradient S is equal to or higher than the predetermined gradient Sref. Therefore, if the vehicle slides down due to torque limitation, the current concentration is eliminated. Similarly, the torque limit is immediately released. On the other hand, when the drive wheels 39a and 39b are locked and current concentration occurs in the motor MG2, for example, since the road surface gradient S is less than the predetermined gradient Sref on a flat road, the twist of the drive shaft 36 is eliminated by the torque limitation. Even if the current concentration is temporarily eliminated, the torque limitation is not immediately released. In this case, as shown in FIG. 5, for example, when the torque Tm2 of the motor MG2 falls below the predetermined torque Terf due to the continuation of the torque limit, that is, when the first condition is satisfied, the torque limit is released (time t32). Therefore, as compared with the comparative example, the time interval for repeating current concentration (time interval from time t31 to time t33) can be lengthened, so that the motor MG2 and the inverter 42 can be suppressed from overheating. ..

In the electric vehicle 20 of the embodiment described above, after the current concentration state is generated in the motor MG2 and the torque limit is executed, the torque Tm2 output from the motor MG2 is less than the predetermined torque Tref, the first condition, the motor. When any of the second condition in which the rotation speed Nm2 of the MG2 is equal to or higher than the predetermined rotation speed Nref and the third condition in which the current concentration state is eliminated and the road surface gradient S is equal to or higher than the predetermined gradient Sref are satisfied, the torque is limited. Cancel the execution. As a result, when current concentration occurs in the motor MG2 when starting on a slope, the road surface gradient S is equal to or higher than the predetermined gradient S. Therefore, when the current concentration is eliminated due to the sliding down of the vehicle caused by the torque limitation, the torque limitation is immediately applied. It will be released. On the other hand, when the drive wheels 39a and 39b are locked and current concentration occurs in the motor MG2, for example, on a flat road or the like, the road surface gradient S is less than the predetermined gradient S, so that the twist of the drive shaft 36 is eliminated by the torque limitation. Even if the current concentration is temporarily eliminated, the torque limitation is not immediately released. As a result, while improving the starting performance on the uphill road, overheating of the motor MG2 and the inverter 42 caused by repeated current concentration in the same phase of the motor MG2 due to the lock of the drive wheels 39a and 39b is suppressed. can do.

In the embodiment, after the torque limit is executed, the execution of the torque limit is canceled when any of the first to third conditions is satisfied. However, one of the first condition and the second condition may not be included as the condition for releasing the torque limit.

In the embodiment, the engine 22 and the motor MG1 are connected to the drive shaft 36 connected to the drive wheels 39a and 39b via the planetary gear 30, the motor MG2 is connected to the drive shaft 36, and the motors MG1 and MG2 are connected by the inverters 41 and 42. The electric vehicle 20 for driving the above is configured. However, as shown in the electric vehicle 120 of the modified example of FIG. 6, the motor MG is connected to the drive shaft 36 connected to the drive wheels 39a and 39b via the transmission 130, and the engine is connected to the motor MG via the clutch 129. The configuration may be a hybrid vehicle in which 22 are connected. Further, the electric vehicle may be configured without an engine.

The correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the motor MG2 corresponds to the "electric motor", and the HVECU 70 and the motor ECU 40 correspond to the "control device".

As for the correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem, the invention described in the column of means for solving the problem in the examples is carried out. Since it is an example for specifically explaining the form for solving the problem, the elements of the invention described in the column of means for solving the problem are not limited. That is, the interpretation of the invention described in the column of means for solving the problem should be performed based on the description in the column, and the examples are the inventions described in the column of means for solving the problem. It is just a concrete example.

Although the embodiments for carrying out the present invention have been described above with reference to Examples, the present invention is not limited to these Examples, and various embodiments are used without departing from the gist of the present invention. Of course, it can be done.

The present invention can be used in the manufacturing industry of electric vehicles and the like.

20,120 Hybrid vehicle, 22 engine, 23 crank position sensor, 24 engine electronic control unit (engine ECU), 26 crank shaft, 28 damper, 30 planetary gear, 36 drive shaft, 38 differential gear, 39a, 39b drive wheel, 40 Electronic control unit for motor (motor ECU), 41,42 inverter, 43,44 rotation position detection sensor, 45u, 45v, 46u, 46v current sensor, 50 battery, 51a voltage sensor, 51b current sensor, 51c temperature sensor, 52 battery Electronic control unit (battery ECU), 54 power line, 70 hybrid electronic control unit (HVECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 Brake pedal position sensor, 88 Vehicle speed sensor, 89 Gradient sensor, 129 clutch, 130 transmission, MG1, MG2, MG motor.

Claims (1)

An electric vehicle including an electric motor for driving a drive wheel and a control device for controlling the electric motor.
The control device executes a torque limit that limits the torque output from the motor when a current concentration state in which the current concentrates in a specific phase of each phase of the motor occurs, and executes the torque limit. The condition that the torque output from the electric motor is less than the predetermined torque, the condition that the current concentration state is eliminated, and the slope of the road surface on which the electric vehicle is traveling is equal to or more than the predetermined slope. When any of the above is satisfied, the execution of the torque limit is released.
Electric vehicle.

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