Electric vehicle

Abstract

To suppress generation of booming while limiting increase of a production cost.SOLUTION: An electric vehicle includes: first and second motors; first and second inverters for respectively driving the first and second motors; and a control device for setting first and second current effective value instructions and first and second current advance angle value instructions of respective first and second current vectors in dq coordinates with a d-axis and a q-axis as coordinate axes on the basis of first and second torque instructions of the first and second motors, respectively, thus controlling the first and second inverters. In a case where a torque difference that is a difference between the first and second torque instructions is a given torque difference or less, with a rotation speed difference that is a difference between first and second rotation speeds of the first and second motors being a given rotation speed difference or less, the control device sets the first and second current effective value instructions and first and second current advance angle value instructions so that a torque variance difference that is a difference between first and second torque variance of the first and second motors becomes equal to or higher than a given torque variance difference.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to electric vehicles. [Background technology]

[0002] Conventionally, as this type of electric vehicle, one that includes an in-wheel motor having a motor for each wheel and a reduction mechanism has been proposed (for example, see Patent Document 1). In this electric vehicle, at least one combination of in-wheel motors has a different combination of the number of teeth in the reduction mechanism, which actively differentiates the frequency of the sounds generated by the in-wheel motors of that combination, thereby suppressing the interference of these sounds to produce a humming noise. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-37133 A Summary of the Invention [Problem to be solved by the invention]

[0004] When the components (hardware configuration) of the in-wheel motor are changed as in the electric vehicle described above, this leads to an increase in manufacturing costs, so one of the challenges is to suppress the generation of the humming noise while suppressing the increase in manufacturing costs.

[0005] The electric vehicle of the present disclosure has a primary objective to suppress the generation of whining noise while suppressing increases in manufacturing costs. [Means for solving the problem]

[0006] The electric vehicle of the present disclosure employs the following measures to achieve the above-mentioned main object.

[0007] The electric vehicle disclosed herein is First and second motors; first and second inverters for driving the first and second motors, respectively; a control device that sets first and second current effective value commands and first and second current advance angle value commands of first and second current vectors in a dq coordinate system having d-axis and q-axis as coordinate axes based on first and second torque commands of the first and second motors, and controls the first and second inverters, when a torque difference, which is a difference between the first and second torque commands, is equal to or smaller than a predetermined torque difference and a rotation speed difference, which is a difference between the first and second rotation speeds of the first and second motors, is equal to or smaller than a predetermined rotation speed difference, the control device sets the first and second current effective value commands and the first and second current advance angle value commands so that a torque fluctuation difference, which is a difference between the first and second torque fluctuations of the first and second motors, is equal to or larger than a predetermined torque fluctuation difference. The gist of the present invention is as follows.

[0008] In the electric vehicle disclosed herein, when the torque difference, which is the difference between the first and second torque commands, is equal to or less than a predetermined torque difference and the rotation speed difference, which is the difference between the first and second rotation speeds of the first and second motors, is equal to or less than the predetermined rotation speed difference, the first and second current effective value commands and the first and second current advance angle value commands are set so that the torque fluctuation difference, which is the difference between the first and second torque fluctuations of the first and second motors, is equal to or greater than the predetermined torque fluctuation difference. The inventors have confirmed through experiments and analysis that when the torque difference is equal to or less than the predetermined torque difference and the rotation speed difference is equal to or less than the predetermined rotation speed difference, the larger the first and second torque fluctuations are, the greater the noise and vibration of the first and second motors are likely to become, and when the noise and vibration of the first and second motors are of the same order of magnitude, a humming noise is likely to occur. Therefore, when the torque difference is equal to or less than a predetermined torque difference and the rotation speed difference is equal to or less than a predetermined rotation speed difference, the inverter is controlled to set the first and second current effective value commands and the first and second current advance angle value commands so that the torque fluctuation difference is equal to or greater than the predetermined torque fluctuation difference, thereby making it possible to increase the sound or vibration of one of the first and second motors and make it more noticeable, while reducing the sound or vibration of the other motor and making it less noticeable. As a result, it is possible to suppress the generation of a humming sound. In other words, it is possible to suppress the generation of a humming sound while suppressing an increase in manufacturing costs compared to a case in which the hardware configuration of the electric vehicle is changed.

[0009] In the electric vehicle disclosed herein, the control device may set the first and second current effective value commands and the first and second current advance angle value commands so as to minimize one of the first and second torque fluctuations, thereby making the other of the noise and vibration of the first and second motors smaller and less noticeable.

[0010] In the electric vehicle disclosed herein, the first and second motors may be mounted so as to be capable of driving left and right drive wheels, respectively. In this case, the condition that the torque difference is equal to or smaller than a predetermined torque difference and the rotation speed difference is equal to or smaller than a predetermined rotation speed difference is likely to be satisfied when traveling straight, etc., and therefore the significance of the present invention is great. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic configuration diagram of an electric vehicle 20 according to an embodiment of the present disclosure. [Diagram 2] 2 is a schematic diagram of an electric drive system provided in an electric vehicle 20. FIG. [Diagram 3] 4 is a flowchart showing an example of a setting processing routine executed by an electronic control unit 70. [Figure 4] 1 is an explanatory diagram showing an example of the relationship between the torque commands Tma*, Tmb*, torque fluctuations TFma, TFmb, current lead-angle commands φia*, φib*, and effective current value commands Ira*, Irb* of the motors 32, 42. FIG. [Diagram 5] FIG. 13 is a schematic diagram of an electric vehicle 120 according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] An embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a schematic configuration diagram of an electric vehicle 20 according to an embodiment of the present disclosure. Fig. 2 is a schematic configuration diagram of an electric drive system provided in the electric vehicle 20. As shown in Fig. 1, the electric vehicle 20 according to the embodiment includes two motors 32, 42, two inverters 34, 44, a battery 50 as an electricity storage device, and an electronic control unit 70 as a control device.

[0013] The motors 32, 42 are configured as synchronous generator motors (in-wheel motors) attached inside the left and right drive wheels 22a, 22b, and drive the left and right drive wheels 22a, 22b. The motors 32, 42 are configured to have the same specifications.

[0014] The inverters 34, 44 are used to drive the motors 32, 42 and are connected to the power line 54. As shown in FIG. 2, the inverter 34 has six transistors T11-T16 as switching elements and six diodes D11-D16 connected in parallel to the six transistors T11-T16, respectively. The transistors T11-T16 are arranged in pairs, two at a time, so as to be on the source side and the sink side of the positive and negative lines of the power line 54, respectively. Each of the connection points of the pair of transistors T11-T16 is connected to each of the three-phase (U-phase, V-phase, W-phase) coils of the motor 32. Therefore, when a voltage is applied to the inverter 34, the electronic control unit 70 adjusts the ratio of the on-time of each of the pair of transistors T11-T16, thereby forming a rotating magnetic field in the three-phase coils and rotating the motor 32. The inverter 44 has six transistors T21-T26 and six diodes D21-D26, similar to the inverter 34. When a voltage is applied to the inverter 44, the electronic control unit 70 adjusts the ratio of the on-time of each pair of the transistors T21-T26, thereby forming a rotating magnetic field in the three-phase coils and driving the motor 42 to rotate.

[0015] 1, the battery 50 is connected to a power line 54 together with the inverters 34, 44. The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel-hydrogen secondary battery.

[0016] The electronic control unit 70 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port, various driving circuits, and various logic ICs. The electronic control unit 70 receives signals from various sensors via the input ports. For example, the electronic control unit 70 receives rotational positions θma and θmb from rotational position sensors 32a and 42a that detect the rotational positions of the rotors of the motors 32 and 42, and phase currents Iua, Iva, Iub, and Ivb from current sensors 32u, 32v, 42u, and 42v that detect the phase currents of the U phase and V phase of the motors 32 and 42. The electronic control unit 70 also receives a voltage Vb from a voltage sensor attached between the terminals of the battery 50, and a current Ib from a current sensor attached to the output terminal of the battery 50. The electronic control unit 70 also receives a start signal from a start switch 80 and a shift position SP from a shift position sensor 82 that detects the operation position of a shift lever 81. The electronic control unit 70 also receives inputs of an accelerator opening Acc from an accelerator pedal position sensor 84 that detects the amount of depression of an accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 that detects the amount of depression of a brake pedal 85, a vehicle speed V from a vehicle speed sensor 87, and a steering angle θst from a steering angle sensor 88.

[0017] The electronic control unit 70 outputs various control signals via an output port. For example, the electronic control unit 70 outputs switching control signals to the transistors T11-T16 and T21-T26 of the inverters 34 and 44. The electronic control unit 70 calculates the electrical angles θea and θeb, angular velocities ωma and ωmb, and rotational speeds Nma and Nmb of the motors 32 and 42 based on the rotational positions θma and θmb of the rotors of the motors 32 and 42 from the rotational position sensors 32a and 42a.

[0018] In the electric vehicle 20 of the embodiment thus configured, the electronic control unit 70 first sets a required torque Td* required for traveling based on the accelerator opening Acc and the vehicle speed V. Next, the torque distribution ratios Da, Db (Da+Db=1) of the motors 32, 42 are set based on the steering angle θst and the like. Then, the required torque Td* is multiplied by the torque distribution ratios Da, Db to set torque commands Tma*, Tmb* of the motors 32, 42. After the torque commands Tma*, Tmb* are set in this manner, switching control is performed on the transistors T11-T16, T21-T26 of the inverters 34, 44 so that the motors 32, 42 are driven by the torque commands Tma*, Tmb*.

[0019] Here, the control of the inverters 34, 44 by the electronic control unit 70 will be described. The inverters 34, 44 are basically controlled by pulse width modulation control (PWM control). In the control of the inverters 34, 44, first, the sum of the phase currents of the phases of the motors 32, 42 is set to zero, and the U-phase phase currents Iua, Iub and the V-phase phase currents Iva, Ivb are coordinate-converted (3-phase-2-phase conversion) into d-axis currents Ida, Idb and q-axis currents Iqa, Iqb in a dq coordinate system having d-axis and q-axis coordinate axes, respectively, using the electrical angles θea, θeb of the motors 32, 42. Next, a setting process routine described later is used to set current effective value commands Ira*, Irb* and current advance angle value commands φia*, φib* of the current vector in the dq coordinate system based on the torque commands Tma*, Tmb* of the motors 32, 42. The current effective value commands Ira*, Irb* are command values ​​for the effective values ​​of the currents supplied to the motors 32, 42, and the current lead angle commands φia*, φib* are command values ​​for the angle (lead angle value) of the current supplied to the motor 32 with respect to the q axis.

[0020] After the current effective value commands Ira*, Irb* and the current lead-angle value commands φia*, φib* are set in this way, the d-axis current commands Ida*, Idb* and the q-axis current commands Iqa*, Iqb* are set based on the current effective value commands Ira*, Irb* and the current lead-angle value commands φia*, φib*. This process is performed taking into consideration that the current effective value commands Ira*, Irb* are obtained as the square root of the sum of the squares of the d-axis current commands Ida*, Idb* and the q-axis current commands Iqa*, Iqb*, and that the current lead-angle value commands φia*, φib* are obtained as the angle (lead-angle value) of the current vector in the dq coordinate system (a vector whose components are the d-axis current commands Ida*, Idb* and the q-axis current commands Iqa*, Iqb*) with respect to the q-axis.

[0021] After the d-axis current commands Ida*, Idb* and the q-axis current commands Iqa*, Iqb* are set in this way, the d-axis voltage commands Vda*, Vdb* and the q-axis voltage commands Vqa*, Vqb* are set so that the differences between the d-axis current commands Ida*, Idb* and the q-axis current commands Iqa*, Iqb* and the d-axis currents Ida, Idb and the q-axis currents Iqa, Iqb are cancelled out. Next, using the electrical angles θea, θeb of the motors 32, 42, the d-axis voltage commands Vda*, Vdb* and the q-axis voltage commands Vqa*, Vqb* are coordinate-transformed (2-phase to 3-phase transformation) into U-phase voltage commands Vua*, Vub*, V-phase voltage commands Vva*, Vvb*, and W-phase voltage commands Vwa*, Vwb*. Then, PWM signals for transistors T11 to T16, T21 to T26 are generated by comparing the U-phase voltage commands Vua*, Vub*, the V-phase voltage commands Vva*, Vvb*, the W-phase voltage commands Vwa*, Vwb*, and the carrier voltage, and the switching of the transistors T11 to T16, T21 to T26 is controlled using the PWM signals for the transistors T11 to T16, T21 to T26.

[0022] Next, the operation of the electric vehicle 20 of this embodiment, in particular the process of setting the current effective value commands Ira*, Irb* and the current lead-angle value commands φia*, φib* of the motors 32, 42 will be described. Fig. 3 is a flowchart showing an example of a setting process routine executed by the electronic control unit 70. This routine is executed repeatedly.

[0023] When this routine is executed, the electronic control unit 70 first calculates the difference ΔTm (the absolute value of the value obtained by subtracting one from the other) between the torque commands Tma*, Tmb* of the motors 32, 42 (step S100), and also calculates the difference ΔNm (the absolute value of the value obtained by subtracting one from the other) between the rotation speeds Nma, Nmb of the motors 32, 42 (step S110).

[0024] Next, it is determined whether the difference ΔTm is equal to or smaller than a threshold value ΔTmth (step S120), and whether the difference ΔNm is equal to or smaller than a threshold value ΔNmth (step S130). Here, the threshold value ΔTmth is a threshold value used to determine whether the torque command Tma* of the motor 32 and the torque command Tmb* of the motor 42 are close to each other, and is determined in advance by experiments, analysis, etc., and is, for example, about several tens of rpm. The threshold value ΔNmth is a threshold value used to determine whether the rotation speed Nma of the motor 32 and the rotation speed Nmb of the motor 42 are close to each other, and is determined in advance by experiments, analysis, etc., and is, for example, about several tens of Nm. The inventors have confirmed that when the torque command Tma* of the motor 32 and the torque command Tmb* of the motor 42 are close to each other and the rotation speed Nma of the motor 32 and the rotation speed Nmb of the motor 42 are close to each other, a humming sound may be generated based on the sound and vibration generated by the motors 32 and 42, which may cause discomfort to the passengers. The threshold values ​​ΔNmth and ΔTmth are determined in advance through experiments, analysis, etc. as the upper limit of the range of the difference ΔNm and the upper limit of the range of the difference ΔTm at which a beat noise may occur.

[0025] When it is determined in step S120 that the difference ΔTm is greater than the threshold ΔTmth, or when it is determined in step S130 that the difference ΔNm is greater than the threshold ΔNmth, it is determined that no beat noise will occur. In this case, the current effective value commands Ira*, Irb* and the current lead-angle value commands φia*, φib* are set by the first setting method (step S140), and this routine ends.

[0026] When it is determined in step S120 that the difference ΔTm is equal to or smaller than the threshold ΔTmth and when it is determined in step S130 that the difference ΔNm is equal to or smaller than the threshold ΔNmth, it is determined that a whine noise may occur. In this case, the current effective value commands Ira*, Irb* and the current lead-angle value commands φia*, φib* are set by the second setting method (step S150), and this routine ends.

[0027] Here, the first and second setting methods will be described. FIG. 4 is an explanatory diagram showing an example of the relationship between the torque commands Tma*, Tmb*, torque fluctuations TFma, TFmb, current lead-angle commands φia*, φib*, and current effective value commands Ira*, Irb* of the motors 32, 42. FIG. 4(A) is an explanatory diagram showing an example of the relationship between the torque commands Tma*, Tmb*, current lead-angle commands φia*, φib*, and current effective value commands Ira*, Irb* of the motors 32, 42. FIG. 4(B) is an explanatory diagram showing an example of the relationship between the torque fluctuations TFma, TFmb, current lead-angle commands φia*, φib*, and current effective value commands Ira*, Irb* of the motors 32, 42. As described above, the motors 32, 42 are configured to have the same specifications. For this reason, in the embodiment, a common relationship is used for the motors 32, 42.

[0028] In the first setting method, using the relationship in Figure 4 (A) and the torque commands Tma*, Tmb* of motors 32, 42, the effective current value commands Ira*, Irb* and current lead-angle commands φia*, φib* are set so that the effective current value commands Ira*, Irb* are minimized while realizing the torque commands Tma*, Tmb*.

[0029] In the second setting method, the current effective value commands Ira*, Irb* and the current lead-angle value commands φia*, φib* are set according to the first or second pattern. In the first pattern, the current effective value command Ira* and the current lead-angle value command φia* are set using Fig. 4(A) and Fig. 4(B) and the torque command Tma* of the motor 32 so that the torque command Tma* is realized and the torque fluctuation TFma of the motor 32 is minimized, and the current effective value command Irb* and the current lead-angle value command φib* are set using Fig. 4(A) and Fig. 4(B) and the torque command Tmb* of the motor 42 so that the difference ΔTFm between the torque fluctuations TFma, TFmb of the motors 32, 42 is equal to or greater than the threshold value ΔTFmth while the torque command Tmb* is realized. The threshold value ΔTFmth is determined in advance by experiment, analysis, etc. so that the generation of a humming sound can be suppressed. 4(A) and 4(B) and the torque command Tmb* of the motor 42, the effective current value command Irb* and the current lead-angle command φib* are set so that the torque fluctuation FTmb of the motor 42 is minimized while realizing the torque command Tmb*, and the effective current value command Ira* and the current lead-angle command φia* are set so that the difference ΔTFm is equal to or greater than the threshold value ΔTFmth while realizing the torque command Tma*, using Figures 4(A) and 4(B) and the torque command Tma* of the motor 32. Note that one of the first pattern and the second pattern may be used all the time, or may be switched periodically (for example, at predetermined time intervals).

[0030] The inventors have confirmed through experiments and analysis that when the difference ΔTm is equal to or less than the threshold ΔTmth and the difference ΔNm is equal to or less than the threshold ΔNmth, the greater the torque fluctuation of the motors 32, 42, the greater the noise and vibration of the motors 32, 42, and the more likely it is that the motors 32, 42 will generate a humming noise when the noise and vibration of the motors 32, 42 are equal to or less than the threshold ΔTmth. In the embodiment, when the difference ΔTm is equal to or less than the threshold ΔTmth and the difference ΔNm is equal to or less than the threshold ΔNmth, the current effective value commands Ira*, Irb* and the current advance angle commands φia*, φib* are set so that the difference ΔTFm is equal to or greater than the threshold ΔTFmth, thereby making it possible to make the noise and vibration of one of the motors 32, 42 louder and more noticeable, while making the noise and vibration of the other motor smaller and less noticeable. As a result, it is possible to suppress the generation of the humming noise. That is, it is possible to suppress the generation of the humming noise while suppressing an increase in manufacturing cost compared to the case of changing the hardware configuration of the electric vehicle 20. By suppressing the generation of the humming sound, it is possible to suppress discomfort felt by the occupants. Moreover, by setting the current effective value commands Ira*, Irb* and the current advance angle commands φia*, φib* so that the torque fluctuation of the motor 32 is minimized in the first pattern, and so that the torque fluctuation of the motor 42 is minimized in the second pattern, it is possible to make the above-mentioned other sound or vibration of the motors 32, 42 smaller and less noticeable. In order to prevent the above-mentioned one sound or vibration of the motors 32, 42 from becoming too large, it is preferable that the difference ΔTFm is as small as possible within a range equal to or greater than the threshold value ΔTFmth, for example, that the difference ΔTFm is set to the threshold value ΔTFmth.

[0031] In the electric vehicle 20 of the present embodiment described above, when the difference ΔTm between the torque commands Tma*, Tmb* of the motors 32, 42 is equal to or less than the threshold value ΔTmth and the difference ΔNm between the rotation speeds Nma, Nmb of the motors 32, 42 is equal to or less than the threshold value ΔNmth, the current effective value commands Ira*, Irb* and the current advance angle value commands φia*, φib* are set so that the difference ΔTFm is equal to or greater than the threshold value ΔTFmth. This makes it possible to make the sound or vibration of one of the motors 32, 42 louder and more noticeable, while making the sound or vibration of the other motor quieter and less noticeable, thereby suppressing the generation of a humming sound. In other words, it is possible to suppress the generation of a humming sound while suppressing an increase in manufacturing costs compared to a case where the hardware configuration of the electric vehicle 20 is changed.

[0032] In the above-described embodiment, when the difference ΔTm is equal to or less than the threshold ΔTmth and the difference ΔNm is equal to or less than the threshold ΔNmth, the electronic control unit 70 sets the effective current value commands Ira*, Irb* and the current lead-angle value commands φia*, φib* so that the torque fluctuation TFma of the motor 32 is minimized in the first pattern and so that the torque fluctuation TFmb of the motor 42 is minimized in the second pattern, but is not limited to this. For example, the effective current value commands Ira*, Irb* and the current lead-angle value commands φia*, φib* may be set so that the torque fluctuation TFma of the motor 32 is within a predetermined range including the minimum in the first pattern and so that the torque fluctuation TFmb of the motor 42 is within this predetermined range in the second pattern.

[0033] In the above-described embodiment, the battery 50 is used as the power storage device, but the present invention is not limited to this. For example, a capacitor or the like may be used as the power storage device in addition to or instead of the battery 50.

[0034] In the above-described embodiment, the motors 32, 42 are mounted inside the left and right drive wheels 22a, 22b, but are not limited to this. For example, the motors 32, 42 may be mounted on the left and right axles.

[0035] In the above-described embodiment, the electric vehicle 20 includes the motors 32, 42 mounted in the left and right drive wheels 22a, 22b, the inverters 34, 44 that drive the motors 32, 42, and the battery 50 connected to the inverters 34, 44 via a power line 52, as shown in Fig. 1, but is not limited thereto. For example, as shown in Fig. 5, an electric vehicle 120 of a modified example may include a motor 132 connected to the front wheels 122a, 122b, a motor 142 connected to the rear wheels 122c, 122d, inverters 134, 144 that drive the motors 132, 142, and a battery 150 connected to the inverters 134, 144 via a power line 152.

[0036] In the above-described embodiment, the electric vehicle 20 is configured to include two motors 32, 42, but is not limited to this. For example, the electric vehicle 20 may be configured as a hybrid vehicle that further includes an engine in addition to the two motors, or as a fuel cell vehicle that includes a fuel cell in addition to the two motors.

[0037] The relationship between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problems will be described. In the embodiment, the motors 32 and 42 correspond to the "first and second motors", the inverters 34 and 44 correspond to the "first and second inverters", and the electronic control unit 70 corresponds to the "control device".

[0038] Note that the correspondence between the main elements of the embodiment and the main elements of the invention described in the Means for Solving the Problem column does not limit the elements of the invention described in the Means for Solving the Problem column, since the embodiment is an example for specifically explaining the form for implementing the invention described in the Means for Solving the Problem column. In other words, the interpretation of the invention described in the Means for Solving the Problem column should be made based on the description in that column, and the embodiment is merely a specific example of the invention described in the Means for Solving the Problem column.

[0039] The above describes embodiments for implementing the present disclosure, but the present disclosure is not limited to these embodiments, and it goes without saying that the present disclosure can be implemented in various forms without departing from the gist of the present disclosure. [Industrial Applicability]

[0040] The present disclosure can be used in the electric vehicle manufacturing industry and the like. [Explanation of symbols]

[0041] 20,120 electric vehicle, 22a,22b driving wheel, 32,42,132,142 motor, 32a,42a rotational position sensor, 32u,32v,42u,42v current sensor, 34,44,134,144 inverter, 50,150 battery, 54,154 power line, 70 electronic control unit, 80 start switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 87 vehicle speed sensor, D11 to D16, D21 to D26 diode, T11 to T16, T21 to T26 transistor.

Claims

1. First and second motors; first and second inverters for driving the first and second motors, respectively; a control device that sets first and second current effective value commands and first and second current advance angle value commands of first and second current vectors in a dq coordinate system having d-axis and q-axis as coordinate axes based on first and second torque commands of the first and second motors, and controls the first and second inverters, the control device sets the first and second current effective value commands and the first and second current advance angle value commands so that a torque fluctuation difference, which is a difference between the first and second torque fluctuations of the first and second motors, becomes equal to or greater than a predetermined torque fluctuation difference when a torque difference, which is a difference between the first and second torque commands, is equal to or less than a predetermined torque difference and a rotation speed difference, which is a difference between the first and second rotation speeds of the first and second motors, is equal to or less than a predetermined rotation speed difference. Electric car.

2. The electric vehicle according to claim 1, the control device sets the first and second current effective value commands and the first and second current advance angle value commands so that one of the first and second torque fluctuations is minimized. Electric car.

3. 3. The electric vehicle according to claim 1 or 2, The first and second motors are mounted so as to be capable of driving the left and right drive wheels, respectively. Electric car.

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