Motor control method, storage medium, program product and vehicle

Abstract

The invention relates to a motor control method, a storage medium, a program product and a vehicle, and the motor control method comprises the steps that a power switch device corresponding to a motor used for driving the vehicle is controlled according to a target current value so as to adjust the torque output by the motor, the target current value comprises a target common-mode current value and a target differential-mode current value, the absolute value of the target differential-mode current value is greater than or equal to the absolute value of the first differential-mode current value, and the first differential-mode current value is the current value of the first phase current of the motor under the condition that the neutral line corresponding to the motor is not conducted. According to the technical scheme, the magnitude of the differential mode current influences the magnitude of the torque of the motor, the power switch device corresponding to the motor is controlled according to the target current value, the torque output by the motor after control can be larger than the torque output by the motor under the condition that the neutral line is not conducted, and therefore the trafficability of the vehicle is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of vehicle technology, and in particular, to a motor control method, a storage medium, a program product, and a vehicle. Background Art

[0002] With the increasing popularity of electric vehicles, users are demanding higher performance from them. Electric vehicles encounter a variety of road conditions, such as climbing hills and getting stuck in deep potholes. These vehicles require strong maneuverability to ensure normal operation under these conditions. Summary of the Invention

[0003] The purpose of the present disclosure is to provide a motor control method, a storage medium, a program product, and a vehicle to increase the torque that the motor can output and improve the vehicle's passability.

[0004] In order to achieve the above objectives, in a first aspect, the present disclosure provides a motor control method, the method comprising: According to the target current value, the power switching device corresponding to the motor used to drive the vehicle is controlled to adjust the torque output by the motor, wherein the target current value includes a target common-mode current value and a target differential-mode current value, the absolute value of the target differential-mode current value is greater than or equal to the absolute value of a first differential-mode current value, and the first differential-mode current value is the current value of the first phase current of the motor when the neutral line corresponding to the motor is not conductive.

[0005] Optionally, before the step of controlling the power switch device corresponding to the motor for driving the vehicle according to the target current value, the method further includes: When a preset condition is met, the neutral line is controlled to be conductive.

[0006] Optionally, the preset condition includes at least one of the following: detecting that the motor is stalled; and the acquired motor demand torque is greater than a specified maximum torque.

[0007] Optionally, the target current value is obtained by: A first differential-mode current parameter is determined based on the required motor torque and a preset correspondence, wherein the preset correspondence includes a correspondence between the motor torque parameter and the differential-mode current parameter, the motor torque corresponding to the motor torque parameter is greater than the specified maximum torque, and the differential-mode current corresponding to the differential-mode current parameter is greater than the specified current amplitude; the target current value is determined based on the first differential-mode current parameter.

[0008] Optionally, the first differential-mode current parameter is a first differential-mode current magnification relative to the specified current amplitude; and determining the target current value according to the first differential-mode current parameter includes: The target differential mode current value is determined according to the first differential mode current value and the first differential mode current amplification factor.

[0009] Optionally, the target differential-mode current value includes target differential-mode current values ​​corresponding to the three-phase windings; and determining the target current value according to the first differential-mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of a first maximum value and a first minimum value, wherein the first maximum value is the maximum value among the target differential-mode current values ​​corresponding to each of the three-phase windings, and the first minimum value is the minimum value among the target differential-mode current values ​​corresponding to each of the three-phase windings.

[0010] Optionally, the first differential-mode current value includes a first differential-mode current value corresponding to each of the three-phase windings; and determining the target current value according to the first differential-mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of the second maximum value and the second minimum value, and the first differential-mode current amplification factor, where the second maximum value is the maximum value of the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value of the first differential-mode current values ​​corresponding to each of the three-phase windings.

[0011] Optionally, determining the target current value according to the first differential mode current parameter further includes: When the motor is not stalled, the target common-mode current value is determined according to the current value of the third harmonic current corresponding to the first phase current and the first differential-mode current magnification.

[0012] Optionally, the first differential-mode current parameter is a second differential-mode current value; and determining the target current value according to the first differential-mode current parameter includes: The target differential mode current value is determined according to the electrical angle of the motor and the second differential mode current value.

[0013] Optionally, the target differential-mode current value includes target differential-mode current values ​​corresponding to the three-phase windings; and determining the target current value according to the first differential-mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of a first maximum value and a first minimum value, wherein the first maximum value is the maximum value among the target differential-mode current values ​​corresponding to each of the three-phase windings, and the first minimum value is the minimum value among the target differential-mode current values ​​corresponding to each of the three-phase windings.

[0014] Optionally, the first differential-mode current value includes a first differential-mode current value corresponding to each of the three-phase windings; and determining the target current value according to the first differential-mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of the second maximum value and the second minimum value, the second differential-mode current value, and the specified current amplitude, wherein the second maximum value is the maximum value among the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value among the first differential-mode current values ​​corresponding to each of the three-phase windings.

[0015] Optionally, determining the target current value according to the first differential mode current parameter further includes: When the motor is not stalled, the target common-mode current value is determined according to the current value of the third harmonic current corresponding to the first phase current, the second differential-mode current value, and the specified current amplitude.

[0016] Optionally, determining the first differential mode current parameter according to the required torque of the motor and a preset corresponding relationship includes: Determine a second differential mode current parameter corresponding to the required torque of the motor from the preset corresponding relationship; and determine the first differential mode current parameter according to the second differential mode current parameter and a specified differential mode current parameter.

[0017] Optionally, determining the first differential mode current parameter according to the second differential mode current parameter and a specified differential mode current parameter includes: If the second differential mode current parameter is greater than the specified differential mode current parameter, the specified differential mode current parameter is used as the first differential mode current parameter; if the second differential mode current parameter is less than or equal to the specified differential mode current parameter, the second differential mode current parameter is used as the first differential mode current parameter.

[0018] Optionally, when the motor is stalled, the specified differential mode current parameter is one of the following: A first preset differential mode current parameter; a maximum differential mode current parameter corresponding to the preset electrical angle of the motor stall; a differential mode current parameter determined based on the difference between the second maximum value and the second minimum value, wherein the first differential mode current value includes the first differential mode current value corresponding to each of the three-phase windings, the second maximum value is the maximum value among the first differential mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value among the first differential mode current values ​​corresponding to each of the three-phase windings.

[0019] Optionally, when the motor is not stalled, the specified differential-mode current parameter is a second preset differential-mode current parameter.

[0020] Optionally, controlling a power switch corresponding to a motor for driving the vehicle according to the target current value includes: The duty cycle corresponding to the target common-mode current value and the duty cycle corresponding to the target differential-mode current value are superimposed to obtain a target duty cycle; and the power switching device is controlled according to the target duty cycle.

[0021] In a second aspect, the present disclosure provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the motor control method provided in the first aspect of the present disclosure are implemented.

[0022] In a third aspect, the present disclosure provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of the motor control method provided in the first aspect of the present disclosure.

[0023] In a fourth aspect, the present disclosure provides a vehicle comprising: a motor for driving the vehicle; a memory on which a computer program is stored; and a processor for executing the computer program in the memory to implement the steps of the motor control method provided in the first aspect of the present disclosure.

[0024] The above technical solution can superimpose the current on the neutral line, that is, superimpose the common-mode current, so that, under the premise that the phase current does not exceed the specified current amplitude, the absolute value of the differential-mode current becomes larger than when the neutral line is not conducting, that is, the absolute value of the target differential-mode current value is greater than or equal to the absolute value of the first differential-mode current value. The magnitude of the differential-mode current affects the magnitude of the motor torque. According to the target current value, the power switching device corresponding to the motor is controlled. The torque that can be output by the motor after control can be greater than the torque that the motor can output when the neutral line is not conducting, thereby improving the vehicle's passability and increasing the utilization rate of the neutral line hardware structure.

[0025] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings: Figure 1 FIG. 1 is a schematic diagram illustrating an exemplary circuit for motor control.

[0027] Figure 2 The figure is a flow chart showing a motor control method according to an exemplary embodiment.

[0028] Figure 31 is a three-phase current waveform showing a motor stalled at an electrical angle of 360° (0°).

[0029] Figure 4 This is a schematic diagram of the amplification of the differential-mode current and the superposition of the common-mode current when the motor is stalled at an electrical angle of 360° (0°).

[0030] Figure 5 This is a schematic diagram of amplifying the common-mode current and differential-mode current after superimposing the common-mode current when the motor is stalled at an electrical angle of 360° (0°).

[0031] Figure 6 1 is a three-phase current waveform showing a motor stalled at an electrical angle of 30°.

[0032] Figure 7 This is a schematic diagram of the amplification of the differential-mode current and the superposition of the common-mode current when the motor is stalled at an electrical angle of 30°.

[0033] Figure 8 This is a schematic diagram of amplifying the common-mode current and differential-mode current after superimposing the common-mode current when the motor is stalled at an electrical angle of 30°.

[0034] Figure 9 Schematic diagram showing the maximum magnification of the differential mode current corresponding to the electrical angle when the motor is stalled.

[0035] Figure 10 This is a schematic diagram of the phase current after the common-mode current is superimposed when the motor is not locked.

[0036] Figure 11 This is a schematic diagram of the phase current after amplifying the differential mode current and the common mode current simultaneously when the motor is not stalled.

[0037] Figure 12 is a flowchart showing a method for determining a target current value according to an exemplary embodiment.

[0038] Figure 13 is a schematic diagram showing a preset corresponding relationship according to an exemplary embodiment.

[0039] Figure 14 is a block diagram of a motor control device according to an exemplary embodiment. DETAILED DESCRIPTION

[0040] The following describes the specific embodiments of the present disclosure in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure.

[0041] First, the circuit for motor control in the present disclosure is described. Figure 1is a schematic diagram of a circuit for motor control, as shown in FIG. Figure 1 As shown, neutral point P1 is the neutral point of the motor used to drive the vehicle. The vehicle can be an electric vehicle, and the motor can be a three-phase permanent magnet synchronous motor (PMSM). The common connection point where the head ends (or tail ends) of the three-phase coils are connected together is the neutral point of the motor, and the wire leading from the neutral point of the motor is the neutral line corresponding to the motor. The vehicle can include at least two battery packs connected in series. The series connection point P2 is the series connection point between any two adjacent battery packs of the vehicle, such as Figure 1 As shown, the series connection point P2 is the series connection point between the battery pack 11 and the battery pack 12. In the present disclosure, the neutral line (also called the center line) can be the circuit between the neutral point P1 and the series connection point P2, and the neutral line can be provided with a fuse 13, a contactor K1 and a shunt 14.

[0042] Figure 1 The circuit shown in the related art is usually used to heat the battery pack of a vehicle. However, the need to heat the battery pack is generally only present in a low temperature environment, resulting in a low structural utilization rate of the neutral line between the neutral point P1 and the series point P2. Figure 1 The circuit shown performs motor control and improves the utilization rate of the hardware structure of the neutral line. In addition to heating the battery pack, it can also increase the maximum torque that the motor can output while ensuring that the phase current of the motor does not exceed the overcurrent threshold, thereby improving the vehicle's passability.

[0043] The basic concepts involved in this disclosure are introduced. The phase current of a motor refers to the current value flowing through the three-phase winding of the motor. Taking the three phases as U phase, V phase, and W phase as an example, the phase current of the motor includes U phase current, V phase current, and W phase current. The U phase current is represented by Iu, the V phase current is represented by Iv, and the W phase current is represented by Iw.

[0044] When there is no neutral line or the neutral line is not conducting, the sum of the three-phase currents is 0, that is, For example, the u-phase current is 100A, the v-phase current is -50A, and the w-phase current is -50A. Furthermore, there is no neutral current, that is, no common-mode current, and all phase currents are differential-mode currents. In this example, the u-phase differential-mode current is 100A, the v-phase differential-mode current is -50A, and the w-phase differential-mode current is -50A.

[0045] When the neutral line is conducting, the neutral line current is equal to the sum of the three-phase currents. , In represents the neutral current. Common mode current is the common part of the three-phase current, which is one third of the neutral current. , Icom represents the common mode current, that is, the neutral line current is 3 times the common mode current.

[0046] When the neutral line is conducting, the phase current = differential mode current + common mode current, and each phase current can be split into common mode current and differential mode current. , , , represents the u-phase differential mode current, represents the v-phase differential mode current, Represents the w-phase differential mode current. The differential mode current satisfies the relationship that the sum of the three phases is 0, that is, .

[0047] Among them, the common-mode current cannot make the motor generate torque, and the common-mode current can be used for battery heating. The differential-mode current is the phase current component that can make the motor generate torque. The size of the differential-mode current affects the size of the motor torque.

[0048] The motor control method disclosed in the present invention is introduced below. Figure 2 This is a flow chart of a motor control method according to an exemplary embodiment. The motor control method can be applied to electronic devices, such as vehicle controllers, motor controllers, etc. Figure 2 As shown, the motor control method may include step 21 .

[0049] Step 21 : Controlling the power switch device corresponding to the motor for driving the vehicle according to the target current value to adjust the torque output by the motor.

[0050] The target current value includes a target common-mode current value and a target differential-mode current value. The absolute value of the target differential-mode current value is greater than or equal to the absolute value of the first differential-mode current value. The first differential-mode current value is the current value of the first phase current of the motor when the neutral line corresponding to the motor is not conductive. The explanation of the neutral line corresponding to the motor can be found in the above description.

[0051] The current value of the first phase current includes the current value Iu1 of the u phase current, the current value Iv1 of the v phase current, and the current value Iw1 of the w phase current. The current value of the first phase current can be obtained by the following formula: , , , where Imax is the specified current amplitude. The specified current amplitude involved in this disclosure refers to the absolute value of the maximum instantaneous value of the phase current, which is a preset value, that is, the maximum positive value that the preset phase current can reach within one cycle. is the electrical angle of the motor, that is, the rotor position angle of the motor. The electrical angle can be obtained through the resolver position sensor.

[0052] The first differential mode current value includes the first differential mode current value corresponding to each of the three phase windings, and the first differential mode current value includes the u phase first differential mode current value Iu_diff1, the v phase first differential mode current value Iv_diff1, and the w phase first differential mode current value Iw_diff1. Since the phase current is the differential mode current when the neutral line is not conducting, the I , I , I .

[0053] The target differential-mode current values ​​include target differential-mode current values ​​corresponding to each of the three-phase windings. The target differential-mode current values ​​include a u-phase target differential-mode current value Iu_diff3, a v-phase target differential-mode current value Iv_diff3, and a w-phase target differential-mode current value Iw_diff3. In the present disclosure, the absolute value of the u-phase target differential-mode current value Iu_diff3 is greater than or equal to the absolute value of the u-phase first differential-mode current value Iu_diff1, the absolute value of the v-phase target differential-mode current value Iv_diff3 is greater than or equal to the absolute value of the v-phase first differential-mode current value Iv_diff1, and the absolute value of the w-phase target differential-mode current value Iw_diff3 is greater than or equal to the absolute value of the w-phase first differential-mode current value Iw_diff1.

[0054] The above technical solution can superimpose the current on the neutral line, that is, superimpose the common-mode current, so that, under the premise that the phase current does not exceed the specified current amplitude, the absolute value of the differential-mode current becomes larger than when the neutral line is not conducting, that is, the absolute value of the target differential-mode current value is greater than or equal to the absolute value of the first differential-mode current value. The magnitude of the differential-mode current affects the magnitude of the motor torque. According to the target current value, the power switching device corresponding to the motor is controlled. The torque that can be output by the motor after control can be greater than the torque that the motor can output when the neutral line is not conducting, thereby improving the vehicle's passability and increasing the utilization rate of the neutral line hardware structure.

[0055] In the present disclosure, the power switch device is controlled according to the target current value, which can be performed when the neutral line is turned on. In one embodiment, if the neutral line is turned on during the motor control process, the power switch device can be directly controlled according to the target current value.

[0056] In another embodiment, before step 21, the motor control method may further include: When the preset conditions are met, the neutral line is controlled to be conductive.

[0057] For example, the controller controls the conduction of the neutral line by controlling Figure 1 The contactor K1 is closed, and after the contactor K1 is closed, the neutral line is turned on.

[0058] For example, the preset condition may include at least one of the following: detecting that the motor is stalled; and the acquired motor demand torque is greater than a specified maximum torque.

[0059] Among them, the stall detection can be performed by using the method used in the relevant technology to determine whether the motor is stalled, for example, judging whether the motor is stalled by the electrical angle of the motor. The motor demand torque can be obtained, for example, based on information such as the vehicle throttle signal. The specified maximum torque refers to the maximum torque that the motor can output when the neutral line is not conducting, which can be pre-calibrated and expressed as Tmax. The specified maximum torque Tmax corresponds to the specified current amplitude Imax, that is, when the maximum differential mode current in the three-phase differential mode current is Imax, the torque that the motor can output is Tmax.

[0060] In addition, the vehicle may be provided with a button for switching to a preset mode, for example. The user can switch the vehicle mode to the preset mode in situations such as when the vehicle is stuck in a deep pit, encounters an obstacle such as a curb, or needs to climb a steep slope or stairs when driving off-road. Switching to the preset mode by the user may indicate that the motor needs to provide greater torque, that is, the motor demand torque is greater than the specified maximum torque.

[0061] In the present disclosure, it is taken into consideration that in situations such as when the motor is stalled or the vehicle is climbing a slope, the motor is required to provide greater power, and the required torque of the motor will be greater than the specified maximum torque. Therefore, the differential mode current can be increased when the neutral line is turned on to increase the maximum torque output by the motor, thereby improving the vehicle's passability.

[0062] Before introducing the detailed implementation of each step in the motor control method of the present disclosure, the maximum degree to which the motor torque can be increased in the present disclosure is first introduced.

[0063] First, let’s consider the situation where the motor is stalled.

[0064] In the absence of a neutral line or when the neutral line is not conducting, the u-phase current can be expressed as , the v-phase current can be expressed as , the w-phase current can be expressed as , is the electrical angle of the motor stall, Represents a multiplication operation.

[0065] Figure 3 1 is a three-phase current waveform showing a motor stalled at an electrical angle of 360° (0°). Figure 3 The figure shows the three-phase current waveform when the motor is stalled at an electrical angle of 360° (0°) without a neutral line or when the neutral line is not conducting. When the motor is stalled, the three-phase AC current becomes a DC current. Figure 3 Taking the current amplitude of 100A as an example, the instantaneous value of the maximum forward current is 100A.

[0066] When the motor is stalled at an electrical angle of 360° (0°), the U-phase current value =100A, v-phase current value =-50A, W phase current value =-50A. Since the phase current is the differential mode current when the neutral line is not conducting, the differential mode current value of the u phase is =100A, v phase differential mode current value =-50A, w phase differential mode current value =-50A.

[0067] Formula (1) is the calculation formula for the maximum amplification factor kmax of the differential mode current when the motor is in a stalled state.

[0068] (Formula 1) Among them, max() is the maximum value function, min() is the minimum value function, and in formula (1), Iu, Iv, and Iw represent the u-phase current value, the v-phase current value, and the w-phase current value, respectively. The specific three-phase current values ​​can be substituted according to the calculation needs.

[0069] According to formula (1), when the motor is stalled at an electrical angle of 360° (0°), the maximum amplification factor of the differential mode current is ≈1.33.

[0070] Figure 4 This is a schematic diagram of the amplification of the differential mode current and the superposition of the common mode current when the motor is stalled and the electrical angle is 360° (0°). Figure 4 (a) is a schematic diagram of the three-phase current when the motor is stalled and the electrical angle is 360° (0°) in the absence of a neutral line or when the neutral line is not conducting. Figure 4 (b) If the neutral line is turned on, the differential mode current will be amplified at the maximum magnification. Schematic diagram of three-phase current after amplification by ≈1.33 times. Figure 4 (b) After amplification, the u-phase current value is also the u-phase differential mode current value. ≈133A, the V phase current value is also the V phase differential mode current value ≈-66.66A, the w-phase current value is also the w-phase differential mode current value ≈-66.66A.

[0071] Formula (2) is the calculation formula for the superimposed neutral line current In_Ref when the motor is in a stalled state.

[0072] (Formula 2) In formula (2), Iu, Iv, and Iw represent the u-phase current value, the v-phase current value, and the w-phase current value, respectively. Specific three-phase current values ​​can be substituted according to calculation needs.

[0073] According to the amplified u-phase current value, v-phase current value and w-phase current value, the neutral line current to be superimposed , the common mode current to be superimposed is one third of the neutral line current to be superimposed, that is, the common mode current to be superimposed is . Figure 4 (c) is the phase current after the amplified differential mode current is superimposed on the common mode current if the neutral line is turned on, that is, each phase differential mode current is added ≈-33.33A, after superimposing the common mode current, such as Figure 4 (c), the U-phase current value is 100 A, the V-phase current value is -100 A, and the W-phase current value is -100 A. Therefore, according to the maximum differential mode current amplification factor kmax, the maximum phase current can reach the maximum positive instantaneous current, and the minimum phase current can reach the maximum negative instantaneous current.

[0074] Figure 5 (a) is a schematic diagram of the three-phase current when the motor is stalled and the electrical angle is 360° (0°) in the absence of a neutral line or when the neutral line is not conducting.

[0075] Figure 5 (b) is a schematic diagram of the three-phase current after the common mode current is superimposed on the premise that the neutral line is turned on and the differential mode current remains unchanged. According to formula (2), the neutral line current to be superimposed is , the common mode current to be superimposed is .like Figure 5 (b) After superimposing a common-mode current of -25A, the u-phase current value is 75A (wherein the u-phase differential-mode current is 100A and the common-mode current is -25A), the v-phase current value is -75A (wherein the v-phase differential-mode current is -50A and the common-mode current is -25A), and the w-phase current value is -75A (wherein the w-phase differential-mode current is -50A and the common-mode current is -25A).

[0076] Figure 5 (c) is a schematic diagram of the three-phase current after the common-mode current and the differential-mode current are amplified together according to the maximum amplification factor. The maximum amplification factor can be calculated according to formula (1): . According to the maximum magnification kmax After amplification, the common mode current is , the u-phase differential mode current value is , the v phase differential mode current value is , the w phase differential mode current value is , the phase current is the sum of the common-mode current and the differential-mode current, then the u-phase current value is 100A, the v-phase current value is -100A, and the w-phase current value is -100A. In this way, the phase current simultaneously reaches the maximum phase current threshold in both the positive and negative directions.

[0077] Figure 4 and Figure 5 The figures show the situation where the motor is stalled at an electrical angle of 360° (0°). Figure 4 This is a method of amplifying the differential mode current first and then superimposing the common mode current. Figure 5 The two processing methods achieve the same effect by first superimposing the common-mode current and then amplifying the differential-mode current and the common-mode current at the same time.

[0078] That is to say, when the motor is stalled at an electrical angle of 360° (0°), if the u-phase differential mode current value is , the v phase differential mode current value is , the w phase differential mode current value is , the common mode current is , to control the motor, so that the three-phase current can be Figure 4 (c) and Figure 5 As shown in (c), the phase currents simultaneously reach the maximum phase current thresholds in both the positive and negative directions, and the three-phase differential-mode current is amplified by approximately 133%. Assuming the instantaneous maximum phase current in the stalled state is 100A, the corresponding maximum torque is Tmax, and the relationship between maximum torque and maximum differential-mode current is linear, the motor torque can be increased to approximately 133% of Tmax after control.

[0079] Figure 6 1 is a three-phase current waveform showing a motor stall at an electrical angle of 30°. Figure 6 The figure shows the three-phase current waveform when the motor is stalled at an electrical angle of 30° in the absence of a neutral line or when the neutral line is not conductive. When the motor is stalled, the three-phase AC current is converted into DC current with a current amplitude of 100A.

[0080] When the motor is stalled at an electrical angle of 30°, the U-phase current value , v-phase current value , w-phase current value Since the phase current is the differential mode current when the neutral line is not conducting, the u-phase differential mode current value is , v phase differential mode current value ,w phase difference mode current value .

[0081] According to formula (1), when the motor is stalled at an electrical angle of 30°, the maximum magnification of the differential mode current is .

[0082] Reference Figure 7 , Figure 7 (a) is a schematic diagram of the three-phase current when the motor is stalled and the electrical angle is 30° when there is no neutral line or the neutral line is not conductive. Figure 7 (b) If the neutral line is turned on, the differential mode current will be amplified at the maximum magnification. After amplifying by times, the schematic diagram of the three-phase current is as follows: Figure 7 (b) After amplification, the u-phase current value, also known as the u-phase differential mode current value, is 100A, the v-phase current value, also known as the v-phase differential mode current value, is 0A, and the w-phase current value, also known as the w-phase differential mode current value, is -100A.

[0083] Calculate the neutral current to be superimposed according to formula (2) , that is, the common mode current to be superimposed is 0A. Figure 7 (c) is the phase current after the amplified differential mode current is superimposed on the common mode current when the neutral line is turned on. Since the superimposed common mode current is 0A, the superimposed u-phase current value is 100A, the v-phase current value is 0A, and the w-phase current value is -100A.

[0084] Reference Figure 8 , Figure 8 (a) is a schematic diagram of the three-phase current when the motor is stalled and the electrical angle is 30° when there is no neutral line or the neutral line is not conductive. Figure 8 (b) is a schematic diagram of the three-phase currents after the common-mode current is superimposed on the premise that the neutral line is turned on and the differential-mode current remains unchanged. According to formula (2), the neutral line current to be superimposed is , that is, the common mode current to be superimposed is 0A.

[0085] like Figure 8 (b) After superimposing the common mode current of 0A, the u-phase current value is , the v-phase current value is 0A, and the w-phase current value is .

[0086] Figure 8 (c) is a schematic diagram of the three-phase current after the common-mode current and the differential-mode current are amplified together according to the maximum amplification factor. The maximum amplification factor can be calculated according to formula (1): . According to the maximum magnification After amplification by times, the common mode current value is 0A, the u-phase differential mode current value is 100A, the v-phase differential mode current value is 0A, and the w-phase differential mode current value is -100A. Then the u-phase current value is 100A, the v-phase current value is 0A, and the w-phase current value is -100A.

[0087] Figure 7 and Figure 8 The figures show the situation where the motor is stalled at an electrical angle of 30°. Figure 7 This is a method of amplifying the differential mode current first and then superimposing the common mode current. Figure 8 The two processing methods achieve the same effect by first superimposing the common-mode current and then amplifying the differential-mode current and the common-mode current at the same time.

[0088] That is to say, when the motor is stalled at an electrical angle of 30°, if the differential mode current value of the u phase is 100A, the differential mode current value of the v phase is 0A, the differential mode current value of the w phase is -100A, and the common mode current value is 0A, the motor can be controlled so that the three-phase current is Figure 7 (c) and Figure 8 As shown in (c), the phase currents simultaneously reach the maximum phase current thresholds in both the positive and negative directions, and the three-phase differential-mode current is amplified by approximately 115%. Assuming the instantaneous maximum phase current in the stalled state is 100A, the corresponding maximum torque is Tmax, and the relationship between maximum torque and maximum differential-mode current is linear. After control, the maximum motor torque can be increased to approximately 115% of Tmax.

[0089] It should be noted that Figure 4 、 Figure 5 、 Figure 7 and Figure 8 , is to explain the effect of superimposing common-mode current and amplifying differential-mode current in the present disclosure when the motor is stalled, and is not the actual motor control process.

[0090] During the entire electrical cycle, the maximum current in the three-phase current is different at different angles when the motor is in a stalled state. When the electrical angle is 0°, 60°, 120°, 180°, 240°, and 300°, the maximum value of the three-phase current is Imax‌‌‌, and the maximum amplification factor of the differential mode current kmax reaches a maximum value of 133%. When the electrical angle is 30°, 90°, 150°, 210°, 270°, and 330°, the maximum value of the three-phase current is , the maximum differential mode current amplification kmax reaches a minimum value of 115%.

[0091] Figure 9 Schematic diagram showing the maximum magnification of differential mode current corresponding to the electrical angle when the motor is stalled. Figure 9 As shown, the maximum differential mode current magnification varies within the range of [ , ] is approximately equal to [1.15, 1.33]. Assuming a linear relationship between maximum torque and maximum differential-mode current, the corresponding maximum motor torque increase range is between 115% and 133%. Where 1.0 corresponds to differential-mode current Imax and maximum torque Tmax.

[0092] The following is for the case where the motor is not stalled.

[0093] Figure 10This is a schematic diagram of the phase current after superimposing the common mode current when the neutral line is turned on and the motor is not locked. When the neutral line is not turned on, the phase current, i.e. the differential mode current, is shown in waveform 101 and is expressed as , where A is the current amplitude. The superimposed common mode current is the third harmonic current , the third harmonic current is as follows Figure 10 The waveform 102 is shown in FIG. The waveform 103 is shown as , waveform 103 represents the phase current after the common mode current is superimposed if the neutral line is turned on. The maximum phase current after superimposing the third harmonic is , which is about 15.47% lower than the maximum value of the original phase current.

[0094] Figure 11 is Figure 10 Based on the above, the schematic diagram of the phase current after the differential mode current and common mode current are amplified at the same time is shown in the figure. The amplification factor is .like Figure 11 As shown, waveform 111 is an enlarged The multiplied differential mode current is expressed as , waveform 112 is amplified The multiplied common mode current is expressed as , waveform 113 represents the phase current after the differential mode current and the common mode current are amplified simultaneously, which is expressed as As shown in waveform 113, the phase current reaches the maximum phase current threshold in both positive and negative directions at the same time.

[0095] That is to say, if the differential mode current , common mode current The motor is controlled, and the phase current after control is as shown in waveform 113. Under the condition that the overcurrent threshold is not exceeded, the fundamental amplitude of the phase current can be increased after the third harmonic is superimposed. , assuming that the relationship between the maximum torque and the maximum differential mode current is linear, the maximum torque of the motor can be increased by 15.47%.

[0096] It should be noted that Figure 10 and Figure 11 , is to explain the effect of superimposing common-mode current and amplifying differential-mode current in the present disclosure when the motor is not blocked, and is not the actual motor control process.

[0097] The following describes a detailed implementation of the present disclosure for determining the target current value.

[0098] Figure 12 FIG. 1 is a flow chart showing a method for determining a target current value according to an exemplary embodiment. Figure 12 As shown, the method for determining the target current value may include step 221 and step 222 .

[0099] Step 221 : determining a first differential mode current parameter according to the motor required torque and a preset corresponding relationship.

[0100] The preset corresponding relationship includes a corresponding relationship between a motor torque parameter and a differential mode current parameter, wherein the motor torque corresponding to the motor torque parameter is greater than a specified maximum torque, and the differential mode current corresponding to the differential mode current parameter is greater than a specified current amplitude.

[0101] In one embodiment, the motor torque parameter can be the torque amplification factor relative to the specified maximum torque Tmax, and the differential mode current parameter can be the differential mode current amplification factor relative to the specified current amplitude Imax, that is, the preset corresponding relationship is the corresponding relationship between the torque amplification factor and the differential mode current amplification factor.

[0102] In another embodiment, the motor torque parameter may be the motor torque value, and the differential mode current parameter may be the differential mode current value, that is, the preset corresponding relationship is the corresponding relationship between the motor torque value and the differential mode current value.

[0103] Figure 13 is a schematic diagram showing a preset corresponding relationship according to an exemplary embodiment. Figure 13 The preset correspondence between the motor torque value and the differential mode current value is used as an example for illustration, where Tmax' represents the maximum torque that the motor can provide that exceeds Tmax, and Imax' represents the maximum differential mode current that exceeds Imax, for example, about 1.33 times Imax.

[0104] The preset corresponding relationship can be obtained through bench test calibration or simulation. In the conventional control mode, the Figure 13 The data in Region I in Figure 1 shows the relationship between motor torque and differential-mode current within the range of a specified maximum torque, Tmax, and a specified current amplitude, Imax. In the present disclosure, the motor torque can be increased to a value greater than Tmax. Therefore, the relationship between motor torque and differential-mode current beyond the specified current amplitude, Imax, can be calculated in advance through bench testing or simulation. Specifically, in Region II, the motor torque is greater than Tmax, and the differential-mode current is greater than Imax.

[0105] It should be noted that the corresponding relationship between motor torque and differential mode current is generally not a simple linear relationship. The above assumption that there is a linear relationship between the two is only to explain the extent to which torque can be amplified.

[0106] Step 221 may be implemented as follows: A second differential mode current parameter corresponding to the required torque of the motor is determined from the preset corresponding relationship.

[0107] For example, if the motor torque parameter is the torque magnification and the differential-mode current parameter is the differential-mode current magnification, for example, Tmax is 100 N.m and the required torque is 110 N.m, then the required torque can be converted to a magnification relative to Tmax, i.e., a torque magnification of 1.1. A preset correspondence is queried based on the torque magnification. For example, a torque magnification of 1.1 corresponds to a differential-mode current magnification of 1.12, and the differential-mode current magnification of 1.12 is used as the second differential-mode current parameter.

[0108] Taking the motor torque parameter as the motor torque value and the differential mode current parameter as the differential mode current value as an example, for example, the required torque is 110 N.m, and the differential mode current value is 112 A according to the preset corresponding relationship. The differential mode current value 112 A is used as the second differential mode current parameter.

[0109] The first differential mode current parameter is determined according to the second differential mode current parameter and the specified differential mode current parameter.

[0110] In the case of motor stall, specify the differential mode current parameter as one of the following: a first preset differential mode current parameter; The maximum differential mode current parameter corresponding to the preset electrical angle of the motor stall; The differential mode current parameter is determined based on the difference between the second maximum value and the second minimum value, wherein the first differential mode current value includes the first differential mode current value corresponding to each of the three-phase windings, the second maximum value is the maximum value among the first differential mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value among the first differential mode current values ​​corresponding to each of the three-phase windings.

[0111] Among them, such as Figure 9 As shown in the figure, when the motor is stalled, the maximum differential mode current amplification factor varies within a certain range in one electrical cycle. [1.15, 1.33], if the differential mode current magnification is stabilized at 1.15, then the differential mode current can be amplified by 1.15 times at all electrical angles. Taking the amplification factor of 1.2 as an example, when the motor is stalled at 30°, the maximum differential mode current amplification factor is only 1.15, and the amplification factor of 1.2 cannot be achieved when the motor is stalled at 30°.

[0112] Therefore, if the differential mode current parameter is the differential mode current magnification, the first preset differential mode current parameter may be relative to the specified current amplitude. 1.15 times, if the differential mode current parameter is the differential mode current value, the first preset differential mode current parameter can be Imax, taking Imax as 100A as an example, the first preset differential mode current parameter is, for example, 115A.

[0113] like Figure 9As shown, the maximum differential mode current magnification at each electrical angle can be pre-stored in the memory, and the controller can obtain the maximum differential mode current parameter corresponding to the electrical angle of the motor stall from the memory. For example, if the motor stalls at 0°, the corresponding preset maximum differential mode current parameter can be relative to the specified current amplitude. In addition, the maximum differential mode current parameter can also be represented by a differential mode current value, for example, the preset maximum differential mode current parameter is about 133A.

[0114] The differential mode current parameter determined according to the difference between the second maximum value and the second minimum value, that is, the maximum differential mode current parameter, that is, the maximum differential mode current, can be stored in advance or calculated in real time.

[0115] Wherein, referring to formula (1), the maximum differential mode current parameter can be calculated according to the following formula (3).

[0116] (Formula 3) Among them, Iu_diff1, Iv_diff1, and Iw_diff1 have been explained above.

[0117] When the motor is not locked, the differential mode current parameter is designated as the second preset differential mode current parameter.

[0118] As mentioned above, when the motor is not locked, the maximum differential mode current can be amplified 1.15 times, the second preset differential mode current parameter can be relative to the specified current amplitude 1.15 times, or, expressed as 115A in terms of current value.

[0119] An implementation method for determining the first differential mode current parameter according to the second differential mode current parameter and the specified differential mode current parameter may be: If the second differential mode current parameter is greater than the specified differential mode current parameter, the specified differential mode current parameter is used as the first differential mode current parameter; If the second differential mode current parameter is less than or equal to the specified differential mode current parameter, the second differential mode current parameter is used as the first differential mode current parameter.

[0120] For example, taking the motor stall as an example, for example, the motor stalls at 30°, the differential mode current parameter is the current amplification factor, and the specified differential mode current parameter is the corresponding maximum differential mode current amplification factor of 1.15 times. If the differential mode current amplification factor obtained according to the motor required torque and the preset correspondence is 1.12 times, then the first differential mode current parameter is the differential mode current amplification factor of 1.12 times. If the differential mode current amplification factor obtained according to the motor required torque and the preset correspondence is 1.2 times, then the first differential mode current parameter is the differential mode current amplification factor of 1.15 times.

[0121] That is, the maximum differential mode current amplification factor can reflect the maximum torque that the motor can currently output, that is, the maximum capacity of the motor. When controlling the motor, the required torque of the motor should be used as the basis, that is, the purpose is to meet the needs of the vehicle.

[0122] In this way, the amount by which the differential-mode current needs to be amplified can be determined based on the motor's required torque to meet the vehicle's current needs, and the specified differential-mode current parameters can be used as a limit to prevent the phase current of the motor from exceeding the specified current amplitude after control.

[0123] Step 222: Determine a target current value according to the first differential mode current parameter.

[0124] In one embodiment, the differential mode current parameter is taken as the differential mode current magnification as an example for explanation.

[0125] In an implementation of step 222, the first differential mode current parameter may be a first differential mode current magnification relative to a specified current amplitude; step 222 may include: A target differential mode current value is determined according to the first differential mode current value and the first differential mode current magnification.

[0126] For each winding in the three-phase windings, the product of the corresponding first differential-mode current value and the first differential-mode current magnification factor may be used as the corresponding target differential-mode current value.

[0127] For example, the first differential mode current magnification is expressed as k, and the target differential mode current value of phase u is , v-phase target differential mode current value , w-phase target differential mode current value .

[0128] In one embodiment, step 222 further includes: When the motor is stalled, the target common-mode current value is determined based on the sum of the first maximum value and the first minimum value, where the first maximum value is the maximum value of the target differential-mode current values ​​corresponding to the three-phase windings, and the first minimum value is the minimum value of the target differential-mode current values ​​corresponding to the three-phase windings.

[0129] For example, the neutral line current In1 can be calculated by the following formula (4).

[0130] (4) Neutral current In1 , which is the target common mode current value. Alternatively, you can directly use the sum of the first maximum value and the first minimum value - , as the target common-mode current value.

[0131] As an example, if the motor is stalled at 0°, the corresponding maximum differential mode current amplification factor is about 1.33 times. The current motor required torque is 110 N.m. The differential mode current amplification factor obtained according to the preset corresponding relationship is 1.12 times, then the first differential mode current amplification factor is 1.12 times.

[0132] When the motor is stalled at 0°, the first differential mode current value of the u-phase is Iu_diff1 = 100A, the first differential mode current value of the v-phase is Iv_diff1 = -50A, and the first differential mode current value of the w-phase is Iw_diff1 = -50A.

[0133] The first differential mode current amplification factor is 1.12 times, so the u-phase target differential mode current value Iu_diff3=112A, the v-phase target differential mode current value Iv_diff3=-56A, and the w-phase target differential mode current value Iw_diff3=-56A.

[0134] Neutral current The target common mode current value is the neutral line current In1 , is -28A.

[0135] In this way, the power switching devices corresponding to the motor are controlled according to the target differential mode current value and the target common mode current value. After control, the U-phase current of the motor is 84A, the V-phase current is -84A, and the W-phase current is -84A.

[0136] It should be noted that in the above introduction to the maximum degree to which the motor torque can be increased, if the maximum differential-mode current amplification factor is used for control, the phase current can simultaneously reach the maximum phase current threshold in both the positive and negative directions. In this example, if the amplification factor of the differential-mode current is less than the maximum amplification factor, the maximum value of the phase current is less than the maximum phase current threshold.

[0137] In one embodiment, step 222 further includes: When the motor is stalled, the target common-mode current value is determined based on the sum of the second maximum value and the second minimum value, and the first differential-mode current amplification factor. The second maximum value is the maximum value of the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value of the first differential-mode current values ​​corresponding to each of the three-phase windings.

[0138] For example, the neutral current In2 can be calculated by the following formula (5).

[0139] (5) Neutral current In1 , and then multiply it by the first differential mode current magnification to get the target common mode current value. Alternatively, you can directly use the sum of the first maximum value and the first minimum value - , then multiplied by the first differential mode current magnification to obtain the target common mode current value Still taking the motor stalled at 0° and the first differential mode current magnification of 1.12 as an example, the neutral line current , neutral line current In2 , and then multiply it by the first differential mode current magnification factor 1.12 to obtain the target common mode current value of -28A.

[0140] In one embodiment, step 222 further includes: When the motor is not stalled, the target common-mode current value is determined according to the current value of the third harmonic current corresponding to the first phase current and the first differential-mode current magnification.

[0141] When the motor is not locked, the superimposed common mode current is the third harmonic current. For example, the phase current is expressed as , the corresponding third harmonic current is expressed as The current value of the corresponding third harmonic current may be multiplied by the first differential mode current magnification to obtain the target common mode current value.

[0142] In one embodiment, the differential mode current parameter is taken as the differential mode current value for explanation.

[0143] An implementation of step 222 may be: the first differential mode current parameter is the second differential mode current value; and step 222 may include: The target differential mode current value is determined according to the electrical angle of the motor and the second differential mode current value.

[0144] The target differential mode current value can be determined by the following formula: , , Iu_diff2 represents the second differential mode current value, is the electrical angle at which the motor stalls. For example, when the motor is stalled at 0°, the second differential-mode current is 112A. Based on this formula, the target differential-mode current value for the U phase, Iu_diff3, is 112A; the target differential-mode current value for the V phase, Iv_diff3, is -56A; and the target differential-mode current value for the W phase, Iw_diff3, is -56A.

[0145] In one embodiment, step 222 further includes: When the motor is stalled, the target common-mode current value is determined based on the sum of the first maximum value and the first minimum value, where the first maximum value is the maximum value of the target differential-mode current values ​​corresponding to the three-phase windings, and the first minimum value is the minimum value of the target differential-mode current values ​​corresponding to the three-phase windings.

[0146] This embodiment may refer to the above-mentioned method for calculating the neutral line current In1 and the target common mode current value.

[0147] In one embodiment, step 222 further includes: When the motor is stalled, a target common-mode current value is determined according to the sum of the second maximum value and the second minimum value, the second differential-mode current value, and the specified current amplitude.

[0148] For example, the second differential mode current value divided by the specified current amplitude can be used as the differential mode current magnification factor. The neutral line current In2 can be calculated by formula (5). The neutral line current In2 is , and then multiply it by the differential mode current magnification to get the target common mode current value.

[0149] In one embodiment, step 222 further includes: When the motor is not stalled, the target common-mode current value is determined according to the current value of the third harmonic current corresponding to the first phase current, the second differential-mode current value, and the specified current amplitude.

[0150] Among them, the superimposed common-mode current is the third harmonic current, which has been introduced above. The second differential-mode current value divided by the specified current amplitude can be used as the differential-mode current amplification factor. The current value of the corresponding third harmonic current can be multiplied by the differential-mode current amplification factor to obtain the target common-mode current value.

[0151] Through the above technical solution, the absolute value of the target differential mode current value is greater than or equal to the absolute value of the first differential mode current value. The magnitude of the differential mode current affects the magnitude of the motor torque. Therefore, controlling the motor according to the target current value can increase the torque that the motor can output.

[0152] The motor control method disclosed herein can be applied to a controller in a vehicle, such as a vehicle controller or a motor controller. In one embodiment, for example, the motor control method is applied to a motor controller. The step of determining the target current value can be performed by the motor controller or the vehicle controller. If the step of determining the target current value is performed by the vehicle controller, the vehicle controller can send the determined target current value to the motor controller.

[0153] In the present disclosure, step 21 may include: The duty cycle corresponding to the target common-mode current value and the duty cycle corresponding to the target differential-mode current value are superimposed to obtain the target duty cycle; The power switching device is controlled according to the target duty cycle.

[0154] The differential-mode current and common-mode current can be decoupled for control. This involves converting the target common-mode current value into a corresponding duty cycle, and the target differential-mode current value into a corresponding duty cycle. The two duty cycles are then superimposed to obtain the target duty cycle. The methods for converting the target common-mode current value into a corresponding duty cycle and the target differential-mode current value into a corresponding duty cycle can be found in related technologies.

[0155] In the present disclosure, the duty cycle corresponding to the target differential-mode current value of the u-phase and the duty cycle corresponding to the target common-mode current value can be superimposed to obtain the target duty cycle of the u-phase, which is used to control the phase current of the u-phase winding. The duty cycle corresponding to the target differential-mode current value of the v-phase and the duty cycle corresponding to the target common-mode current value can be superimposed to obtain the target duty cycle of the v-phase, which is used to control the phase current of the v-phase winding. The duty cycle corresponding to the target differential-mode current value of the w-phase and the duty cycle corresponding to the target common-mode current value can be superimposed to obtain the target duty cycle of the w-phase, which is used to control the phase current of the w-phase winding.

[0156] In this way, after the power switching device is controlled according to the target duty cycle, the phase current of the motor does not exceed the specified current amplitude, and the absolute value of the differential mode current becomes larger than when the neutral line is not conducting, which is equivalent to the differential mode part in the phase current becoming larger. The larger the differential mode current, the greater the torque that the motor can output. After control, the torque that the motor can output is greater than the torque that the motor can output when the neutral line is not conducting, thereby improving the vehicle's passing performance.

[0157] In addition, the controller can obtain real-time temperatures of power switching devices such as IGBTs (Insulated-Gate Bipolar Transistors) and motors. If the temperature of the IGBT or motor exceeds a set temperature threshold, the controller can control the neutral contactor to disconnect, terminate the motor control method, and resume normal motor control. Furthermore, if the motor is detected to be out of service, or the required torque is less than the specified maximum torque, or the user switches to normal driving mode, which does not require torque greater than the specified maximum torque, the controller can terminate the motor control method and resume normal motor control.

[0158] Based on the same inventive concept, the present disclosure also provides a motor control device, Figure 14 is a block diagram of a motor control device according to an exemplary embodiment. Figure 14As shown, the motor control device 1400 may include: a first control module 1401, used to control the power switching device corresponding to the motor for driving the vehicle according to the target current value to adjust the torque output by the motor, wherein the target current value includes a target common-mode current value and a target differential-mode current value, the absolute value of the target differential-mode current value is greater than or equal to the absolute value of the first differential-mode current value, and the first differential-mode current value is the current value of the first phase current of the motor when the neutral line corresponding to the motor is not conductive.

[0159] Optionally, the motor control device 1400 may further include: a second control module for controlling the neutral line to be conductive when preset conditions are met before the first control module 1401 controls the power switching device corresponding to the motor for driving the vehicle according to the target current value.

[0160] Optionally, the preset condition includes at least one of the following: detecting that the motor is stalled; and the acquired motor demand torque is greater than a specified maximum torque.

[0161] Optionally, the target current value is obtained through the following modules: a first determination module, used to determine the first differential-mode current parameter based on the motor required torque and a preset correspondence, the preset correspondence including the correspondence between the motor torque parameter and the differential-mode current parameter, the motor torque corresponding to the motor torque parameter is greater than the specified maximum torque, and the differential-mode current corresponding to the differential-mode current parameter is greater than the specified current amplitude; a second determination module, used to determine the target current value based on the first differential-mode current parameter.

[0162] Optionally, the first differential-mode current parameter is a first differential-mode current amplification factor relative to the specified current amplitude; the second determination module includes: a third determination module, used to determine the target differential-mode current value based on the first differential-mode current value and the first differential-mode current amplification factor.

[0163] Optionally, the target differential-mode current value includes the target differential-mode current value corresponding to each of the three-phase windings; the second determination module further includes: a fourth determination module, which is used to determine the target common-mode current value based on the sum of the first maximum value and the first minimum value when the motor is stalled, wherein the first maximum value is the maximum value among the target differential-mode current values ​​corresponding to each of the three-phase windings, and the first minimum value is the minimum value among the target differential-mode current values ​​corresponding to each of the three-phase windings.

[0164] Optionally, the first differential-mode current value includes the first differential-mode current value corresponding to each of the three-phase windings; the second determination module further includes: a fifth determination module, which is used to determine the target common-mode current value based on the sum of the second maximum value and the second minimum value, and the first differential-mode current amplification factor when the motor is stalled, wherein the second maximum value is the maximum value of the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value of the first differential-mode current values ​​corresponding to each of the three-phase windings.

[0165] Optionally, the second determination module further includes: a sixth determination module, which is used to determine the target common-mode current value based on the current value of the third harmonic current corresponding to the first phase current and the first differential-mode current amplification factor when the motor is not stalled.

[0166] Optionally, the first differential mode current parameter is a second differential mode current value; the second determination module includes: a seventh determination module, used to determine the target differential mode current value according to the electrical angle of the motor and the second differential mode current value.

[0167] Optionally, the target differential-mode current value includes the target differential-mode current value corresponding to each of the three-phase windings; the second determination module further includes: an eighth determination module, which is used to determine the target common-mode current value based on the sum of the first maximum value and the first minimum value when the motor is stalled, wherein the first maximum value is the maximum value among the target differential-mode current values ​​corresponding to each of the three-phase windings, and the first minimum value is the minimum value among the target differential-mode current values ​​corresponding to each of the three-phase windings.

[0168] Optionally, the first differential-mode current value includes the first differential-mode current value corresponding to each of the three-phase windings; the second determination module further includes: a ninth determination module, which is used to determine the target common-mode current value according to the sum of the second maximum value and the second minimum value, the second differential-mode current value and the specified current amplitude when the motor is stalled, wherein the second maximum value is the maximum value among the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value among the first differential-mode current values ​​corresponding to each of the three-phase windings.

[0169] Optionally, the second determination module further includes: a tenth determination module, which is used to determine the target common-mode current value based on the current value of the third harmonic current corresponding to the first phase current, the second differential-mode current value, and the specified current amplitude when the motor is not stalled.

[0170] Optionally, the first determination module includes: an eleventh determination module, used to determine the second differential mode current parameter corresponding to the motor required torque from the preset correspondence; and a twelfth determination module, used to determine the first differential mode current parameter based on the second differential mode current parameter and the specified differential mode current parameter.

[0171] Optionally, the twelfth determination module is used to: if the second differential-mode current parameter is greater than the specified differential-mode current parameter, use the specified differential-mode current parameter as the first differential-mode current parameter; if the second differential-mode current parameter is less than or equal to the specified differential-mode current parameter, use the second differential-mode current parameter as the first differential-mode current parameter.

[0172] Optionally, in the event that the motor stalls, the specified differential-mode current parameter is one of the following: a first preset differential-mode current parameter; a maximum differential-mode current parameter corresponding to the preset electrical angle of the motor stall; a differential-mode current parameter determined based on the difference between a second maximum value and a second minimum value, wherein the first differential-mode current value includes the first differential-mode current value corresponding to each of the three-phase windings, the second maximum value is the maximum value among the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value among the first differential-mode current values ​​corresponding to each of the three-phase windings.

[0173] Optionally, when the motor is not stalled, the specified differential-mode current parameter is a second preset differential-mode current parameter.

[0174] Optionally, the first control module 1401 includes: a duty cycle determination module, used to superimpose the duty cycle corresponding to the target common-mode current value and the duty cycle corresponding to the target differential-mode current value to obtain a target duty cycle; and a control submodule, used to control the power switching device according to the target duty cycle.

[0175] The present disclosure provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the motor control method provided in the above embodiment of the present disclosure are implemented.

[0176] The present disclosure provides a computer program product, including a computer program, which implements the steps of the motor control method provided in the above embodiment of the present disclosure when the computer program is executed by a processor.

[0177] In a fourth aspect, the present disclosure provides a vehicle, comprising: a motor for driving the vehicle; a memory on which a computer program is stored; and a processor for executing the computer program in the memory to implement the steps of the motor control method provided in the above-mentioned embodiment of the present disclosure.

[0178] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0179] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0180] In addition, the various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A motor control method, characterized in that: The method comprises: According to the target current value, the power switching device corresponding to the motor used to drive the vehicle is controlled to adjust the torque output by the motor, wherein the target current value includes a target common-mode current value and a target differential-mode current value, the absolute value of the target differential-mode current value is greater than or equal to the absolute value of a first differential-mode current value, and the first differential-mode current value is the current value of the first phase current of the motor when the neutral line corresponding to the motor is not conductive.

2. The method according to claim 1, wherein: Before the step of controlling the power switch device corresponding to the motor for driving the vehicle according to the target current value, the method further includes: When a preset condition is met, the neutral line is controlled to be conductive.

3. The method according to claim 2, characterized in that The preset condition includes at least one of the following: detecting that the motor is stalled; The obtained motor demand torque is greater than the specified maximum torque.

4. The method according to claim 1, wherein The target current value is obtained as follows: Determining a first differential-mode current parameter according to a required motor torque and a preset corresponding relationship, wherein the preset corresponding relationship includes a corresponding relationship between a motor torque parameter and a differential-mode current parameter, wherein the motor torque corresponding to the motor torque parameter is greater than a specified maximum torque, and the differential-mode current corresponding to the differential-mode current parameter is greater than a specified current amplitude; The target current value is determined according to the first differential mode current parameter.

5. The method according to claim 4, characterized in that The first differential mode current parameter is a first differential mode current magnification relative to the specified current amplitude; The determining the target current value according to the first differential mode current parameter includes: The target differential mode current value is determined according to the first differential mode current value and the first differential mode current amplification factor.

6. The method according to claim 5, characterized in that The target differential mode current value includes the target differential mode current value corresponding to each of the three-phase windings; The determining the target current value according to the first differential mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of a first maximum value and a first minimum value, wherein the first maximum value is the maximum value among the target differential-mode current values ​​corresponding to each of the three-phase windings, and the first minimum value is the minimum value among the target differential-mode current values ​​corresponding to each of the three-phase windings.

7. The method according to claim 5, characterized in that The first differential mode current value includes the first differential mode current value corresponding to each of the three-phase windings; The determining the target current value according to the first differential mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of the second maximum value and the second minimum value, and the first differential-mode current amplification factor, where the second maximum value is the maximum value of the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value of the first differential-mode current values ​​corresponding to each of the three-phase windings.

8. The method according to claim 5, characterized in that The determining the target current value according to the first differential mode current parameter further includes: When the motor is not stalled, the target common-mode current value is determined according to the current value of the third harmonic current corresponding to the first phase current and the first differential-mode current magnification.

9. The method according to claim 4, characterized in that The first differential mode current parameter is a second differential mode current value; The determining the target current value according to the first differential mode current parameter includes: The target differential mode current value is determined according to the electrical angle of the motor and the second differential mode current value.

10. The method according to claim 9, characterized in that The target differential mode current value includes the target differential mode current value corresponding to each of the three-phase windings; The determining the target current value according to the first differential mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of a first maximum value and a first minimum value, wherein the first maximum value is the maximum value among the target differential-mode current values ​​corresponding to each of the three-phase windings, and the first minimum value is the minimum value among the target differential-mode current values ​​corresponding to each of the three-phase windings.

11. The method according to claim 9, characterized in that The first differential mode current value includes the first differential mode current value corresponding to each of the three-phase windings; The determining the target current value according to the first differential mode current parameter further includes: In the event that the motor is stalled, the target common-mode current value is determined based on the sum of the second maximum value and the second minimum value, the second differential-mode current value, and the specified current amplitude, wherein the second maximum value is the maximum value among the first differential-mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value among the first differential-mode current values ​​corresponding to each of the three-phase windings.

12. The method according to claim 9, characterized in that The determining the target current value according to the first differential mode current parameter further includes: When the motor is not stalled, the target common-mode current value is determined according to the current value of the third harmonic current corresponding to the first phase current, the second differential-mode current value, and the specified current amplitude.

13. The method according to claim 4, characterized in that The determining of the first differential mode current parameter according to the required torque of the motor and the preset corresponding relationship includes: Determining a second differential mode current parameter corresponding to the required torque of the motor from the preset corresponding relationship; The first differential mode current parameter is determined according to the second differential mode current parameter and a specified differential mode current parameter.

14. The method according to claim 13, characterized in that The determining the first differential mode current parameter according to the second differential mode current parameter and the specified differential mode current parameter includes: If the second differential mode current parameter is greater than the specified differential mode current parameter, using the specified differential mode current parameter as the first differential mode current parameter; If the second differential-mode current parameter is less than or equal to the specified differential-mode current parameter, the second differential-mode current parameter is used as the first differential-mode current parameter.

15. The method according to claim 13 or 14, characterized in that When the motor is stalled, the specified differential mode current parameter is one of the following: a first preset differential mode current parameter; A maximum differential mode current parameter corresponding to a preset electrical angle at which the motor is stalled; A differential mode current parameter is determined based on the difference between the second maximum value and the second minimum value, wherein the first differential mode current value includes the first differential mode current value corresponding to each of the three-phase windings, the second maximum value is the maximum value among the first differential mode current values ​​corresponding to each of the three-phase windings, and the second minimum value is the minimum value among the first differential mode current values ​​corresponding to each of the three-phase windings.

16. The method according to claim 13 or 14, characterized in that When the motor is not stalled, the specified differential-mode current parameter is a second preset differential-mode current parameter.

17. The method according to claim 1, wherein The controlling of the power switch device corresponding to the motor for driving the vehicle according to the target current value includes: Superimposing the duty cycle corresponding to the target common-mode current value and the duty cycle corresponding to the target differential-mode current value to obtain a target duty cycle; The power switch device is controlled according to the target duty cycle.

18. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 17 are implemented.

19. A computer program product, characterized in that The invention comprises a computer program, which, when executed by a processor, implements the steps of the method according to any one of claims 1 to 17.

20. A vehicle, characterized in that: The vehicle comprises: an electric motor for driving the vehicle; a memory having a computer program stored thereon; A processor, configured to execute the computer program in the memory to implement the steps of the method according to any one of claims 1 to 17.

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