Vehicle control method and vehicle control device

Abstract

To provide a vehicle control device which realizes d-axis current control capable of preventing generation of unintended torque.SOLUTION: An electric motor (30) has rotation angle detection means (31) which detects a rotation angle of a rotor. Output torque output from the electric motor (30) is controlled by setting a d-axis current command value and a q-axis current command value using a magnet magnetic flux of the electric motor (30), a d-axis inductance, a q-axis inductance and the rotation angle. When applying only d-axis current to the electric motor (30) while a vehicle (1) is stopped, the d-axis current command value is set to a positive value and the q-axis current command value is set to 0. The d-axis current command value is set so that torque generated on the electric motor does not exceed predetermined allowable torque by using a predetermined detection error of the rotation angle.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle control method and a vehicle control device. [Background technology]

[0002] In controlling a vehicle that uses an electric motor as a driving force source, d-axis current control may be performed in which only d-axis current flows through the electric motor, and no q-axis current flows, so that current flows through the windings without generating torque in the electric motor. This control can warm up the battery, discharge the charge of the capacitor, etc.

[0003] Patent Document 1 discloses a configuration in which a d-axis current command value is set to a positive value and a q-axis current command value is set to zero, thereby controlling the torque of an electric motor to approximately zero. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-259570 A Summary of the Invention

[0005] When controlling the torque of an electric motor by setting the q-axis current command value to 0 as in the conventional technology, if there is a detection error in the rotor rotation angle of the electric motor, the detection error may cause the d-axis current value and q-axis current value to change, which may result in unintended torque being generated in the electric motor.

[0006] An object of the present invention is to provide a vehicle control device that realizes d-axis current control that can suppress the generation of unintended torque by performing control that takes into account detection errors in the rotor rotation angle.

[0007] One aspect of the present invention is a method for controlling a vehicle including an electric motor and a power conversion device that supplies power to the electric motor. The electric motor is provided with a rotation angle detection means for detecting a rotation angle of a rotor, and this control method controls an output torque output by the electric motor by setting a d-axis current command value and a q-axis current command value using a magnet magnetic flux, a d-axis inductance, a q-axis inductance, and a rotation angle of the electric motor, and when performing control to flow only a d-axis current of the electric motor when the vehicle is stopped, the d-axis current command value is set to a positive value and the q-axis current command value is set to 0, and the d-axis current command value is set using a detection error of a preset rotation angle so that the torque generated in the electric motor does not exceed a preset allowable torque.

[0008] According to the present invention, when d-axis current control is performed to pass only the d-axis current through the electric motor when the vehicle is stopped, the d-axis current command value is set so that the torque generated due to detection error in the rotation angle does not exceed the allowable torque, thereby preventing the electric motor from generating unintended torque. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is an explanatory diagram of a drive device for a vehicle according to the present embodiment. [Diagram 2] FIG. 2 is a functional block diagram of the control device for the vehicle. [Diagram 3] FIG. 3 is an explanatory diagram showing the d-axis current and the q-axis current in the detection error θe. [Figure 4] FIG. 4 is a flowchart of the d-axis current control process. [Diagram 5] FIG. 5 is a diagram illustrating an example of a motor temperature vs. magnet magnetic flux map. [Figure 6] FIG. 6 is a diagram illustrating an example of a rotation angle-inductance map. [Figure 7] FIG. 7 is a time chart of the d-axis current control. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0011] FIG. 1 is an explanatory diagram of a vehicle 1 equipped with a drive device 2 of the present embodiment.

[0012] The vehicle 1 of this embodiment is configured as an electric vehicle or a hybrid vehicle that runs on the driving force of an electric motor 30 as a part or the whole of a driving source. The vehicle 1 includes a driving device 2 and a vehicle controller 3.

[0013] The drive device 2 includes a control device 10, an inverter 20, a battery 25, and an electric motor 30.

[0014] The control device 10 controls the operation of the inverter 20 based on a torque command from the vehicle controller 3 to adjust the power supplied to the electric motor 30, thereby controlling the driving force of the electric motor 30. The control device 10 has a controller and a storage device, and the controller executes a program stored in the storage device to realize the functions of each part shown in Fig. 2 and execute the flowchart shown in Fig. 4.

[0015] The inverter 20 has a power module, and converts DC power supplied from the battery 25 into power suitable for driving the electric motor 30 , and drives the electric motor 30 .

[0016] The electric motor 30 is, for example, a permanent magnet embedded synchronous motor, and is driven by three-phase AC power supplied from the inverter 20. The driving force of the electric motor 30 is transmitted to drive wheels 35 via a reduction gear 33 and an axle 34. When the vehicle 1 decelerates, the electric motor 30 also functions as a generator that generates regenerative power. The electric motor 30 includes a resolver 31 that detects the magnetic pole position (rotation angle) θ of the rotor, and a temperature sensor 32 that detects the temperature of the electric motor 30. Although not shown, cooling water is configured to flow between the inverter 20, the battery 25, and the electric motor 30 in order to cool them and keep them at an appropriate temperature.

[0017] The vehicle controller 3 instructs the control device 10 of the command torque Te* calculated based on the state of the vehicle 1. The vehicle controller 3 also sends the current vehicle speed to the control device 10. The vehicle controller 3 also receives signals from an accelerator pedal 101, a foot brake pedal 102, and a parking lock 103, and sends these signals to the control device 10.

[0018] FIG. 2 is a functional block diagram of the control device 10 of the vehicle 1 according to the present embodiment.

[0019] The control device 10 controls the rotation of the electric motor 30 based on the command torque Te* and the rotation angular velocity ω of the electric motor 30. The command torque Te* is input from the vehicle controller 3. The rotation angular velocity ω is a value converted by a rotation speed calculation unit 80 as described below based on the rotation angle θ acquired by the resolver 31.

[0020] The control device 10 includes a PWM signal generating unit 40, a modulation factor generating unit 50, a dq-uvw converting unit 60, a uvw-dq converting unit 70, a rotation speed calculating unit 80, a d-axis PI compensating unit 90, a q-axis PI compensating unit 100 and a current command value generating unit 110.

[0021] The current command value generating unit 110 calculates a d-axis current command value idr and a q-axis current command value iqr for vector control from the command torque Te*, the rotational angular velocity ω of the electric motor 30, and the motor temperature T of the electric motor 30 using a pre-stored map or the like.

[0022] The q-axis current command value iqr calculated by the current command value generation unit 110 is subtracted by the q-axis current iqs actually flowing through the electric motor 30 in an addition / subtraction unit 111 to obtain a difference Δiq, and this difference Δiq is input to the q-axis PI compensation unit 100. The q-axis PI compensation unit 100 calculates a q-axis voltage component vq that acts in a direction to subtract the difference Δiq.

[0023] The d-axis current command value idr calculated by the current command value generation unit 110 is subtracted by the d-axis current ids actually flowing through the electric motor 30 in an addition / subtraction unit 109 to obtain a difference Δid, and this difference Δid is input to the d-axis PI compensation unit 90. The d-axis PI compensation unit 90 calculates a d-axis voltage component vd that acts in a direction to subtract the difference Δid.

[0024] The q-axis voltage component vq and the d-axis voltage component vd calculated in this manner are input to the dq-uvw conversion unit 60. The dq-uvw conversion unit 60 converts the two-phase voltage values ​​of the q and d axes into three-phase voltage values ​​vu, vv, and vw. The converted three-phase voltage values ​​are converted by the modulation factor generation unit 50 into modulation factor command values ​​for the u, v, and w phases, respectively, and sent to the PWM signal generation unit 40.

[0025] The PWM signal generating unit 40 outputs signals for operating each of the u-phase, v-phase, and w-phase of the inverter 20 based on the modulation factor command value input from the modulation factor generating unit 50. As a result, the inverter 20 converts the DC power from the battery 25 into three-phase AC power and supplies currents to the u-phase, v-phase, and w-phase of the electric motor 30, respectively.

[0026] The current sensor 201 detects the current values ​​iu, iv supplied by the inverter 20 to the electric motor 30. The detected current values ​​iu, iv are input to a UVW-dq conversion unit 70. Since the sum of the current values ​​iv, iu, iw is zero, iw is found by calculation in the UVW-dq conversion unit 70. The UVW-dq conversion unit 70 converts the current values ​​iv, iu, iw into a d-axis current ids and a q-axis current iqs, respectively, based on the rotation angle θ. The converted current values ​​are input to addition and subtraction units 109 and 111.

[0027] In this way, by performing feedback control based on the difference between the actual current value supplied to the electric motor 30 and the command current value based on the command torque Te*, a feedback control unit is configured that causes the electric motor 30 to generate an actual torque corresponding to the command torque Te*.

[0028] When the electric motor 30 rotates, a rotation angle θ, which is a reference axis of a current vector in the rotor, is detected by the resolver 31. The rotation angle θ of the rotor is input to a dq-uvw conversion unit 60 and a uvw-dq conversion unit 70, which synchronize the dq axis components based on the rotation angle θ.

[0029] The rotation angle θ of the rotor detected by the resolver 31 is also input to a rotation speed calculation unit 80. The rotation speed calculation unit 80 calculates a rotation angular velocity ω from the rotation angle θ and inputs it to a current command value generation unit 110.

[0030] Next, the operation of the control device 10 configured in this manner will be described in more detail.

[0031] As described above, the control device 10 drives the electric motor 30 by controlling the d-axis current and the q-axis current based on the command torque Te*.

[0032] Here, in order not to drive the electric motor 30, a control (d-axis current control) may be performed in which the q-axis current, which is a component that contributes to the torque of the electric motor 30, is set to 0 and the d-axis current flows only through the d-axis, which does not contribute to the torque of the electric motor 30. For example, when the vehicle 1 is stopped, the inverter 20 can be safely stopped by consuming the charge of a capacitor provided in the inverter 20, or the inverter 20 and the electric motor 30 can be forcibly heated by passing a d-axis current through the electric motor 30, and the battery 25 can be warmed up using the cooling water that has been heated by these.

[0033] It is known that the resolver 31 that detects the rotation angle of the rotor of the electric motor 30 contains a detection error in its detection result. The detection error of the resolver 31 occurs due to a structural error or an installation error of the resolver 31. If the resolver 31 has a detection error, the q-axis current iqs may flow through the electric motor 30 even if the q-axis current command value iqr is set to 0.

[0034] FIG. 3 is an explanatory diagram showing the values ​​of the d-axis current ids and the q-axis current iqs relative to the d-axis current command value idr when the resolver 31 has a detection error, that is, when there is a detection error in the rotation angle of the rotor.

[0035] As shown in FIG. 3, due to the presence of a detection error (angle) θe in the rotation angle of the rotor, the d-axis current ids and q-axis current iqs that actually flow through the electric motor 30 in response to the d-axis current command value idr are determined by trigonometric functions as the product of the d-axis current command value idr and the sine function of the detection error θe, and the product of the d-axis current command value idr and the cosine function of the detection error θe, respectively.

[0036] In this way, the q-axis current iqs is generated due to the detection error θe of the rotor rotation angle, and an unintended torque is generated in the electric motor 30 during d-axis current control.

[0037] Here, the torque generated by the electric motor 30 will be described.

[0038] The torque Ts generated by the electric motor 30 is expressed by the following equation 1, where pn is the number of magnetic poles, Φa is the rotor magnet magnetic flux, Ld is the d-axis inductance, Lq is the q-axis current, iqs is the d-axis current, and ids is the d-axis current.

[0039]

number

[0040] Here, as shown in FIG. 3 described above, when the q-axis current iqs and the d-axis current ids are converted into an equation for the d-axis current command value idr including the detection error θe of the rotor rotation angle, the generated torque Ts of the electric motor 30 is expressed as the following Equation 2.

[0041]

number

[0042] This formula 2 can be expressed as the following formula 3.

[0043]

number

[0044] What can be seen from Equation 3 is that the d-axis current command value idr can be found from the detection error θe of the rotor rotation angle and the torque Ts generated by the electric motor 30. Here, the number of magnetic poles pn, the rotor magnet magnetic flux Φa, the d-axis inductance Ld, and the q-axis inductance Lq are values ​​determined by the characteristics of the electric motor 30.

[0045] In this embodiment, by using Equation 3, the torque Ts generated in the electric motor 30 due to a detection error in the rotor rotation angle is controlled so as not to exceed the allowable torque, thereby suppressing the generation of unintended torque in the electric motor 30 during d-axis current control.

[0046] In this embodiment, the maximum value of the detection error of the rotor rotation angle detected by the resolver 31 is obtained by experiment or simulation, and is set in advance as the detection error θe of the rotor rotation angle. Then, the allowable torque of the electric motor 30 is set based on the state of the vehicle 1, and in the d-axis current control, the control described below is executed so that the torque generated by the electric motor 30 does not exceed the allowable torque.

[0047] 4 is a flowchart of the d-axis current control process executed by the control device 10. The process of this flowchart is executed by the control device 10 at a predetermined cycle (for example, at intervals of 10 ms).

[0048] First, in step S10, the control device 10 acquires the current vehicle speed and the depression amount of the accelerator pedal 101 from the vehicle controller 3 and determines whether the vehicle is stopped. If it is determined that the vehicle is not stopped because the vehicle speed is greater than 0 km / h and / or the depression amount of the accelerator pedal 101 is equal to or greater than a predetermined amount, the control device 10 ends this flow chart and goes into standby.

[0049] When it is determined that the vehicle is in a stopped state, the control device 10 then sets an allowable value of the generated torque Ts based on the state of the vehicle 1 through the processes of steps S20 to S60.

[0050] First, in step S20, the control device 10 obtains the state of the parking lock 103 from the vehicle controller 3 and determines whether the parking lock 103 is in a state (operated state) that keeps the vehicle 1 stopped by fixing the rotating shaft of the electric motor 30 or the reducer 33.

[0051] If it is determined that the park lock 103 is in an activated state, the process proceeds to step S40. If it is determined that the park lock 103 is not in an activated state, the process proceeds to step S30.

[0052] In step S30, the control device 10 acquires the brake fluid pressure of the foot brake pedal 102 from the vehicle controller 3, and determines whether the brake fluid pressure is equal to or greater than a predetermined value when the foot brake pedal 102 is depressed to keep the vehicle 1 in a stopped state (activated state). If the brake fluid pressure is equal to or greater than the predetermined value, the process proceeds to step S50. If the brake fluid pressure is less than the predetermined value, the process proceeds to step S60.

[0053] The predetermined value of the brake fluid pressure in step S30 is a brake fluid pressure that allows the driver to stop the vehicle 1 by depressing the foot brake pedal 102. This predetermined value is set in advance based on the vehicle weight and the characteristics of the foot brake pedal 102, and is stored in the control device 10.

[0054] In step S40, the control device 10 sets the allowable torque of the generated torque Ts to a value A. In this case, since the vehicle 1 is being braked by the parking lock 103, the allowable torque of the electric motor 30 is set to the value A so as not to exceed the braking force of the parking lock 103.

[0055] In step S50, the control device 10 sets the allowable torque of the generated torque Ts to a value B. In this case, since the vehicle 1 is braked by the foot brake, the allowable torque of the electric motor 30 is set to the value B corresponding to the brake fluid pressure so as not to exceed the braking force due to the brake fluid pressure of the foot brake pedal 102.

[0056] In step S60, the control device 10 sets the allowable torque of the generated torque Ts to a value C. In this case, since the vehicle 1 is not being braked by the brakes or the like, the allowable torque of the electric motor 30 is set to the value C based on the weight and rolling resistance of the vehicle 1.

[0057] Next, the control device 10 sets the d-axis current command value idr so that the torque Ts generated by the electric motor 30 does not exceed the allowable torque value (value A, value B or value C) set by the processing of steps S40 to S60.

[0058] First, in step S70, the control device 10 sets the magnet magnetic flux Φa based on the motor temperature T acquired from the temperature sensor 32 and by referring to a preset magnet magnetic flux map.

[0059] FIG. 5 is a diagram illustrating an example of a motor temperature vs. magnet magnetic flux map.

[0060] The permanent magnet of the electric motor 30 has a characteristic that the higher the temperature, the lower the magnet magnetic flux Φa. Therefore, a motor temperature-magnet magnetic flux map in which the motor temperature T and the magnet magnetic flux Φa values ​​are obtained and set through experiments, simulations, etc., is stored in advance in the control device 10. The control device 10 sets the magnet magnetic flux Φa corresponding to the motor temperature T of the electric motor 30 by referring to this motor temperature-magnet magnetic flux map.

[0061] In this way, by setting the magnet magnetic flux Φa in accordance with the motor temperature T of the electric motor 30, it is possible to more precisely control the electric motor 30 in accordance with the motor temperature T.

[0062] Next, in step S80, the control device 10 sets the value of the d-axis inductance Ld and the value of the q-axis inductance Lq based on the rotation angle θ acquired from the resolver 31.

[0063] FIG. 6 is a diagram illustrating an example of a rotation angle-inductance map.

[0064] 6, the value of the d-axis inductance Ld and the value of the q-axis inductance Lq vary according to the rotation angle θ of the electric motor 30. Therefore, a rotation angle-inductance map in which the value of the d-axis inductance Ld and the value of the q-axis inductance Lq for the rotation angle θ are obtained and set by experiments, simulations, etc. is stored in advance in the control device 10. The control device 10 sets the d-axis inductance Ld and the q-axis inductance Lq corresponding to the rotation angle θ of the electric motor 30 by referring to this rotation angle-inductance map.

[0065] In this way, by setting the d-axis inductance Ld and the q-axis inductance Lq in accordance with the rotation angle θ of the electric motor 30, the electric motor 30 can be controlled more precisely.

[0066] Next, in step S90, the control device 10 substitutes the set allowable torque value for the generated torque Ts in Equation 3, and calculates the d-axis current command value idr using the number of magnetic poles pn of the electric motor 30, the magnet magnetic flux Φa set in step S70, and the d-axis inductance Ld and q-axis inductance Lq set in step S80.

[0067] The d-axis current command value idr obtained in step S90 is calculated as a value that does not exceed the allowable torque (value A, value B, or value C) set according to the state (braking state) of the vehicle 1 as described above, even if the electric motor 30 generates torque when d-axis current control is executed while the rotor rotation angle has a detection error θe.

[0068] That is, the detection error θe of the rotor rotation angle detected by the resolver 31 is the maximum value of the detection errors obtained by experiments and simulations. Therefore, the detection error of the rotor rotation angle actually detected by the resolver 31 does not exceed the detection error θe. Therefore, the electric motor 30 controlled by the d-axis current command value idr and the q-axis current command value iqr (=0) obtained in step S90 does not generate a torque Ts that exceeds the allowable torque. Since the allowable torque is set according to the braking state of the vehicle 1 as described above, the vehicle 1 will not move against the braking force unless the torque Ts generated by the electric motor 30 exceeds the allowable torque.

[0069] Furthermore, the d-axis current command value idr calculated in step S90 can be said to be the maximum current value that can be applied to the d-axis of the electric motor 30 in a state in which the vehicle 1 is not moving against the braking force.

[0070] FIG. 7 is a time chart of the d-axis current control in this embodiment.

[0071] In the time chart shown in FIG. 7, the generated torque Ts, the d-axis current value, the q-axis current value, and the rotation angle θ of the electric motor 30 are plotted against time on the horizontal axis.

[0072] At timing t0, the d-axis current command value idr and the q-axis current command value iqr are both 0, and the electric motor 30 is not generating torque.

[0073] Next, at timing t1, when the d-axis current control is started, the q-axis current iqs, which is the actual current value flowing through the electric motor 30, becomes a positive value with respect to the q-axis current command value iqr (=0) due to the detection error θe of the rotor rotation angle. This causes the electric motor 30 to generate torque.

[0074] At this time, the control device 10 controls the electric motor 30 based on the d-axis current command value idr calculated based on the flowchart of Fig. 4. Through this control, the torque Ts generated by the electric motor 30 is controlled not to exceed the allowable torque (value A, value B, or value C) after timing t2. In the d-axis current control, by controlling the torque Ts generated by the electric motor 30 not to exceed the allowable torque, it is possible to pass a current through the d-axis of the electric motor 30 without the vehicle 1 moving against the braking force.

[0075] As described above, this embodiment relates to a control device 10 that controls a vehicle 1 that includes an electric motor 30 and an inverter 20 as a power conversion device that supplies power to the electric motor 30. The electric motor 30 is provided with a resolver 31 as a rotation angle detection means that detects the rotation angle of a rotor. The control device 10 controls the output torque output by the electric motor 30 by setting a d-axis current command value idr and a q-axis current command value iqr using the magnet magnetic flux Φa, d-axis inductance Ld, q-axis inductance Lq, and rotation angle θ of the electric motor 30. When the vehicle 1 is stopped and d-axis current control is performed to pass only the d-axis current of the electric motor 30, the d-axis current command value idr is set to a positive value and the q-axis current command value iqr is set to 0, and the d-axis current command value idr is set so that the generated torque Ts generated in the electric motor 30 does not exceed the allowable torque using a detection error θe of the rotor rotation angle that is set in advance.

[0076] In this configuration, when d-axis current control is performed to pass only the d-axis current of the electric motor 30 while the vehicle 1 is stopped, the d-axis current command value idr is set so that the torque Ts generated by the detection error θe of the rotor rotation angle detected by the resolver 31 does not exceed the allowable torque, thereby preventing the electric motor 30 from generating unintended torque. Then, d-axis current control can be performed to pass a current through the d-axis of the electric motor 30 within a range in which the electric motor 30 does not exceed the allowable torque.

[0077] In this embodiment, the detection error θe is set based on the maximum value of the detection error of the rotor rotation angle. This maximum value determines the maximum torque Ts that can be generated by the electric motor 30 in the d-axis current control, so that the allowable torque can be set so that the electric motor 30 does not output a torque that exceeds this maximum value, thereby preventing the electric motor 30 from generating unintended torque.

[0078] Furthermore, in this embodiment, the allowable torque is set according to the stopped state of the vehicle 1, so that the generated torque Ts of the electric motor 30 can be controlled so as not to exceed the allowable torque based on the state of the vehicle 1.

[0079] Furthermore, in this embodiment, the allowable torque is set based on at least one of the state of the parking lock 103 of the vehicle 1 and the state of the foot brake pedal 102 of the vehicle 1. Therefore, by setting the allowable torque based on the braking state of the vehicle 1, it is possible to perform d-axis current control while preventing the vehicle 1 from moving.

[0080] In addition, in this embodiment, when the d-axis current command value idr is set, the values ​​of the d-axis inductance Ld and the q-axis inductance Lq are set in accordance with the detected rotation angle θ.

[0081] In this configuration, the electric motor 30 can be controlled more precisely in accordance with the rotation angle θ of the electric motor 30.

[0082] Furthermore, in this embodiment, the magnet magnetic flux Φa of the electric motor 30 is set according to the motor temperature T of the electric motor 30, so that the electric motor 30 can be controlled more precisely according to the motor temperature T.

[0083] Although the embodiments of the present invention have been described above, the above-mentioned embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above-mentioned embodiments.

[0084] Furthermore, in the d-axis current control of this embodiment, after the processing of step S10 in the flowchart of FIG. 4 described above, the allowable torque may be set to a desired value without detecting the operating state of the parking lock 103 and the foot brake pedal 102, and then the processing of step S70 may be executed.

[0085] 4, the motor temperature T may not be detected, and a value of the magnet magnetic flux Φa preset based on the characteristics of the electric motor 30 may be used. Similarly, in step S80, the d-axis inductance Ld and the q-axis inductance Lq preset based on the characteristics of the electric motor 30 may be used, and a rotation angle θ may not be detected, and a d-axis inductance Ld and a q-axis inductance Lq may be used. [Explanation of symbols]

[0086] 1: vehicle, 2: drive unit, 3: vehicle controller, 10: control unit, 20: inverter, 25: battery, 30: electric motor, 31: resolver, 32: temperature sensor, 101: accelerator pedal, 102: foot brake pedal, 103: parking lock

Claims

1. A method for controlling a vehicle including an electric motor and a power conversion device that supplies power to the electric motor, comprising: the electric motor is provided with a rotation angle detection means for detecting a rotation angle of a rotor, an output torque output by the electric motor is controlled by setting a d-axis current command value and a q-axis current command value using a magnet magnetic flux, a d-axis inductance, a q-axis inductance, and the rotation angle of the electric motor; When the vehicle is stopped, in the case where control is performed to flow only the d-axis current of the electric motor, setting the d-axis current command value to a positive value and setting the q-axis current command value to 0, and setting the d-axis current command value using a preset detection error of the rotation angle so that a generated torque generated in the electric motor does not exceed a predetermined allowable torque. How to control a vehicle.

2. A vehicle control method according to claim 1, comprising: the detection error is set based on a maximum value of a detection error of the rotation angle of the rotor detected by the rotation angle detection means. How to control a vehicle.

3. A vehicle control method according to claim 1, comprising: The allowable torque is set according to a stopped state of the vehicle. How to control a vehicle.

4. A vehicle control method according to claim 3, comprising: The allowable torque is set based on at least one of an operating state of a parking lock of the vehicle and an operating state of a foot brake of the vehicle. How to control a vehicle.

5. A vehicle control method according to claim 1, comprising: When the d-axis current command value is set, values ​​of the d-axis inductance and the q-axis inductance are set in accordance with the detected rotation angle. How to control a vehicle.

6. A vehicle control method according to claim 5, comprising: the value of the magnet magnetic flux of the electric motor is set in accordance with the temperature of the electric motor; How to control a vehicle.

7. A vehicle control device that controls an operation of an electric motor in a vehicle including an electric motor and a power conversion device that supplies electric power to the electric motor, comprising: The electric motor is provided with a rotation angle detection means for detecting a rotation angle, The control device includes: an output torque output by the electric motor is controlled by setting a d-axis current command value and a q-axis current command value using a magnet magnetic flux, a d-axis inductance, a q-axis inductance, and the rotation angle of the electric motor; When the vehicle is stopped, in the case where control is performed to flow only the d-axis current of the electric motor, setting the d-axis current command value to a positive value and setting the q-axis current command value to 0, and setting the d-axis current command value using a preset detection error of the rotation angle so that a generated torque generated in the electric motor does not exceed a predetermined allowable torque. Vehicle control device.

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