Power-assisted motor control method, device and system, vehicle and readable storage medium

Abstract

The invention provides a power-assisted motor control method, device and system, a vehicle and a readable storage medium. The method comprises the following steps: acquiring a rotor position angle and dq-axis current under a two-phase rotating coordinate system; calculating a current angle under a two-phase rotating coordinate system according to the dq-axis current, and calculating a current vector angle under a two-phase static coordinate system according to the rotor position angle and the current angle; determining a first compensation amount and a second compensation amount according to the current vector angle, compensating the first compensation amount for the alpha-axis reference voltage U alpha under the two-phase static coordinate system, and compensating the second compensation amount for the beta-axis reference voltage U beta under the two-phase static coordinate system, so as to compensate the output voltage error of the three-phase inverter of the power-assisted motor in the dead time, the torque ripple of the three-phase inverter caused by the output voltage error in the dead time is inhibited; the values of the first compensation amount and the second compensation amount are in one-to-one correspondence with the current vector angle interval where the current vector angle is located. According to the method, the torque ripple of the power-assisted motor can be inhibited.

Description

Technical Field

[0001] The present invention relates to the field of control technology, and in particular to a power assist motor control method, device, system, vehicle, and readable storage medium. Background Art

[0002] The Electric Power Steering (EPS) system improves the dynamic and static performance of the car during steering and ensures the car's handling stability, thus gaining more and more attention. Modern cars generally require the steering system to be safe and reliable, easy to operate, and energy-efficient. In any driving state, the steering wheel and wheels must not produce self-excited vibration or shake to ensure a safe, quiet, and comfortable driving environment. Therefore, high requirements are placed on the control of the power-assisted motor. However, the existing power-assisted motor will have obvious torque pulsation due to the dead zone effect of the three-phase inverter, causing the steering wheel connected to the power-assisted motor to pulsate, reducing the dynamic and static performance of the car during steering. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a power-assisted motor control method, device, system, vehicle, and readable storage medium, wherein the control method compensates for the α-axis reference voltage Uα and the β-axis reference voltage Uβ of the power-assisted motor in a stationary coordinate system respectively to compensate for the output voltage error of the three-phase inverter of the power-assisted motor during the dead time, thereby suppressing the torque pulsation of the three-phase inverter caused by the output voltage error during the dead time, thereby effectively suppressing the torque pulsation of the power-assisted motor and improving the dynamic and static performance of the vehicle during the steering process.

[0004] In order to achieve the above object, in a first aspect, the present invention provides a power assist motor control method, comprising:

[0005] Obtain the rotor position angle and the dq axis current in the two-phase rotating coordinate system;

[0006] Calculating a current angle in a two-phase rotating coordinate system according to the dq-axis current, and calculating a current vector angle in a two-phase stationary coordinate system according to the rotor position angle and the current angle; and

[0007] Determining a first compensation amount and a second compensation amount according to the current vector angle, and compensating the α-axis reference voltage Uα in the two-phase stationary coordinate system by the first compensation amount, and compensating the β-axis reference voltage Uβ in the two-phase stationary coordinate system by the second compensation amount, so as to compensate for an output voltage error of the three-phase inverter of the power assist motor during a dead time, thereby suppressing a torque pulsation caused by the output voltage error of the three-phase inverter during the dead time;

[0008] The current vector angle changes sequentially in a plurality of current vector angle intervals, and the values ​​of the first compensation amount and the second compensation amount correspond one-to-one to the current vector angle interval in which the current vector angle is located.

[0009] In one embodiment, determining the first compensation amount and the second compensation amount according to the current vector angle includes:

[0010] Determine a first compensation coefficient and a second compensation coefficient according to the current vector angle, wherein the values ​​of the first compensation coefficient and the second compensation coefficient correspond one-to-one to the current vector angle interval in which the current vector angle is located;

[0011] The first compensation amount is calculated and determined according to the first compensation coefficient, and the second compensation amount is determined according to the second compensation coefficient.

[0012] In one embodiment, the first compensation amount is defined as U1, the second compensation amount is defined as U2, and the first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship:

[0013] U1=K1*Td*Udc / Ts, U2=K2*Td*Udc / Ts;

[0014] Among them, Td is the dead time of the power-assisted motor, Udc is the bus voltage of the power-assisted motor, Ts is the carrier period of the power-assisted motor, K1 and K2 are respectively the first compensation coefficient and the second compensation coefficient, and when the current vector angle is in any of the current vector angle intervals, there is a corresponding preset first compensation coefficient and the second compensation coefficient, and the first compensation coefficient and the second compensation coefficient are obtained according to the current vector angle interval in which the current vector angle is currently located.

[0015] In one embodiment, the current vector angle is defined as θ, the current vector angle corresponding to any phase current in the three-phase current passing through the zero point is defined as the mutation angle θ', and the preset optimization angle is defined as δ;

[0016] Determining a first compensation amount and a second compensation amount according to the current vector angle includes:

[0017] When the current vector angle is in a current vector angle interval outside the mutation interval, determining a first compensation coefficient and a second compensation coefficient according to the current vector angle, and further calculating and determining the first compensation amount according to the first compensation coefficient, and determining the second compensation amount according to the second compensation coefficient;

[0018] When the current vector angle is in the mutation interval, a third compensation coefficient is determined according to the current vector angle, the mutation angle, the preset optimization angle and the first linearization equation, and a fourth compensation coefficient is determined according to the current vector angle, the mutation angle, the preset optimization angle and the second linearization equation, and the first compensation amount is further calculated and determined according to the third compensation coefficient, and the second compensation amount is determined according to the fourth compensation coefficient;

[0019] Among them, the mutation interval is the vector angle interval corresponding to (θ'±δ), the values ​​of the first compensation coefficient and the second compensation coefficient correspond one-to-one to the current vector angle interval in which the current vector angle is located, the first linearized equation is the linearized equation corresponding to the current vector angle being in the vector angle interval of (θ'+δ), the second linearized equation is the linearized equation corresponding to the current vector angle being in the vector angle interval of (θ'-δ), and the first linearized equation is different from the second linearized equation.

[0020] In one embodiment, the first compensation amount is defined as U1, and the second compensation amount is defined as U2;

[0021] When the current vector angle is in a current vector angle interval outside the mutation interval, the first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship:

[0022] U1=K1*Td*Udc / Ts, U2=K2*Td*Udc / Ts

[0023] When the current vector angle is in the mutation interval, the first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship:

[0024]

[0025] Among them, Td is the dead time of the power-assisted motor, Udc is the bus voltage of the power-assisted motor, and Ts is the carrier period of the power-assisted motor; K1 and K2 are the first compensation coefficient and the second compensation coefficient, respectively. When the current vector angle is in any of the current vector angle intervals, there is a corresponding preset first compensation coefficient and the second compensation coefficient, and the first compensation coefficient and the second compensation coefficient are obtained according to the current vector angle interval in which the current vector angle is currently located.

[0026] In one embodiment, the value of the preset optimization angle δ is less than or equal to 10 degrees.

[0027] In one embodiment, the current vector angle is equal to the sum of the rotor position angle and the current angle.

[0028] In one embodiment, obtaining the dq axis current in a two-phase rotating coordinate system includes:

[0029] The three-phase currents are sampled and converted into dq-axis currents in a two-phase rotating coordinate system.

[0030] In a second aspect, the present invention provides a power-assisted motor control device, comprising a memory and a processor, wherein the memory stores a computer program executable by the processor, and when the processor executes the computer program, the power-assisted motor control method as described in any of the above embodiments is implemented.

[0031] In a third aspect, the present invention provides a power-assisted motor control system, comprising a power-assisted motor and the power-assisted motor control device as described above.

[0032] In a fourth aspect, the present invention provides a vehicle, comprising the power-assisted motor control system as described above.

[0033] In a fifth aspect, the present invention provides a readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the power assist motor control method as described in any of the above embodiments.

[0034] Compared with the prior art, the present invention has the following beneficial effects: the power-assisted motor control method provided by the present invention compensates for the α-axis reference voltage Uα and the β-axis reference voltage Uβ of the power-assisted motor in a stationary coordinate system respectively, so as to compensate for the output voltage error of the three-phase inverter of the power-assisted motor during the dead time, thereby suppressing the torque pulsation caused by the output voltage error of the three-phase inverter during the dead time, thereby effectively suppressing the torque pulsation of the power-assisted motor, helping to reduce the pulsation of the steering wheel connected to the power-assisted motor, and improving the dynamic and static performance of the vehicle using the power-assisted motor during the steering process.

[0035] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 It is a flow chart of a power assist motor control method provided by one embodiment of the present invention.

[0038] Figure 2It is a structural block diagram of a power assist motor control system provided by one embodiment of the present invention.

[0039] Figure 3 1 is the magnitude and direction diagram of the compensation voltage vector in one embodiment of the present invention.

[0040] Figure 4 2 is a schematic diagram of a compensation voltage-current angle curve corresponding to an α-axis reference voltage Uα and a β-axis reference voltage Uβ in one embodiment of the present invention.

[0041] Figure 5 It is a schematic diagram of a current waveform curve of the output current of the power assist motor in one embodiment of the present invention before compensation by the α-axis reference voltage Uα and the β-axis reference voltage Uβ.

[0042] Figure 6 It is a schematic diagram of a current waveform curve of the output current of the power assist motor in one embodiment of the present invention after compensation with the α-axis reference voltage Uα and the β-axis reference voltage Uβ.

[0043] Figure 7 2 is a schematic diagram of compensation voltage-current angle curves corresponding to the α-axis reference voltage Uα and the β-axis reference voltage Uβ in another embodiment of the present invention.

[0044] Description of main reference numerals:

[0045] 100- power-assisting motor control system; 10- power-assisting motor; 20- power-assisting motor control device;

[0046] 21-current sampling and conversion module; 22-rotor position angle sampling module; 23-voltage compensation module. DETAILED DESCRIPTION

[0047] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0048] Please also read Figure 1 and Figure 2 The embodiment of the present invention provides a power-assist motor control method, which is applied to a power-assist motor control system 100. The power-assist motor control system 100 includes a power-assist motor 10 and a power-assist motor control device 20 connected to the power-assist motor 10. The power-assist motor control device 20 is used to execute the power-assist motor control method provided by the embodiment of the present invention to control the power-assist motor 10, thereby effectively suppressing the torque pulsation of the power-assist motor 10.

[0049] Specifically, Figure 1 As shown, in an embodiment of the present invention, the power assist motor control method comprises the following steps:

[0050] Step S1, obtaining the rotor position angle and the dq axis current in the two-phase rotating coordinate system;

[0051] Step S2, calculating the current angle in the two-phase rotating coordinate system according to the dq axis current, and calculating the current vector angle in the two-phase stationary coordinate system according to the rotor position angle and the current angle; and

[0052] Step S3, determining a first compensation amount and a second compensation amount according to the current vector angle, and compensating the α-axis reference voltage Uα in the two-phase stationary coordinate system with the first compensation amount, and compensating the β-axis reference voltage Uβ in the two-phase stationary coordinate system with the second compensation amount, so as to compensate for the output voltage error of the three-phase inverter of the power-assisted motor during the dead time, thereby suppressing the torque pulsation caused by the output voltage error of the three-phase inverter during the dead time.

[0053] It should be noted that, in the embodiment of the present invention, the current vector angle changes sequentially in a plurality of current vector angle intervals, and the values ​​of the first compensation amount and the second compensation amount correspond one-to-one to the current vector angle interval in which the current vector angle is located. In other words, there is a one-to-one corresponding logical relationship between the first compensation amount, the second compensation amount, and the current vector angle interval in which the current vector angle is located, and the logical relationship can be stored in the power assist motor control device 20, so that when determining the current vector angle, the power assist motor control device 20 can determine the corresponding first compensation amount and the second compensation amount according to the logical relationship, and respectively compensate the α-axis reference voltage Uα and the β-axis reference voltage Uβ in the two-phase stationary coordinate system, which will be described in more detail later. It can be understood by those skilled in the art that the output voltage error of the three-phase inverter during the dead time will be different depending on the polarity of the three-phase current. The output voltage error may be a positive error (i.e., the output voltage is greater than the required voltage) or a negative error (i.e., the output voltage is less than the required voltage). Accordingly, the first compensation amount and the second compensation amount can achieve negative compensation to offset the positive error, or can achieve positive compensation to offset the negative error.

[0054] To sum up, in the power-assisted motor control method provided in an embodiment of the present invention, the α-axis reference voltage Uα and the β-axis reference voltage Uβ of the power-assisted motor 10 in the stationary coordinate system are compensated respectively to offset the output voltage error of the three-phase inverter of the power-assisted motor 10 during the dead time, thereby suppressing the torque pulsation caused by the output voltage error of the three-phase inverter during the dead time, thereby effectively suppressing the torque pulsation of the power-assisted motor 10, helping to reduce the pulsation of the steering wheel connected to the power-assisted motor 10, and improving the dynamic and static performance of the vehicle using the power-assisted motor 10 during the steering process.

[0055] More specifically, Figure 2 As shown, in one embodiment of the present invention, the power-assisted motor control device 20 includes a current sampling and conversion module 21, a rotor position angle sampling module 22 and a voltage compensation module 23 respectively connected to the power-assisted motor 10, and the current sampling and conversion module 21 and the rotor position angle sampling module 22 are also respectively connected to the voltage compensation module 23.

[0056] Among them, Figure 2 In the example, the current sampling conversion module 21 is used to sample the three-phase current of the power assist motor 10 and convert the three-phase current into the dq axis current in the two-phase rotating coordinate system. That is, the step S1 of obtaining the dq axis current in the two-phase rotating coordinate system includes: sampling the three-phase current and converting the three-phase current into the dq axis current in the two-phase rotating coordinate system. It should be noted that in Figure 2 In the example, the method of sampling the three-phase current can be, but is not limited to, sampling through the lower bridge resistor, or sampling through the output Hall sensor, or sampling through the busbar single resistor. These sampling methods are all prior art. In addition, converting the sampled three-phase current into the dq axis current in the two-phase rotating coordinate system is also prior art, which will not be elaborated. It should also be noted that in Figure 2 In the example, the current sampling transformation module 21 is also used to perform an inverse tangent calculation on the dq axis current to obtain the current angle in the two-phase rotating coordinate system. In other embodiments, the current sampling transformation module 21 can also send the dq axis current obtained by converting the three-phase current to the voltage compensation module 23, and the voltage compensation module 23 performs an inverse tangent calculation on the dq axis current to obtain the current angle in the two-phase rotating coordinate system. It is not difficult to understand that performing an inverse tangent calculation on the dq axis current to obtain the current angle in the two-phase rotating coordinate system can be implemented using existing technology, which will not be elaborated on.

[0057] exist Figure 2In the example, the rotor position angle sampling module 22 is not limited to using at least one of an optical encoder, a magnetic encoder, a rotary encoder, and a sine-cosine encoder to sample the rotor position angle of the power-assisted motor 10. The principle of sampling the rotor position angle by any of the aforementioned encoders is prior art and will not be elaborated on.

[0058] Please refer again Figure 2 In one embodiment of the present invention, the current sampling conversion module 21 can send the current angle in the two-phase rotating coordinate system obtained by sampling the three-phase current to the voltage compensation module 23, and the rotor position angle sampling module 22 can send the sampled rotor position angle to the voltage compensation module 23, so that the voltage compensation module 23 calculates the current vector angle in the two-phase stationary coordinate system according to the rotor position angle and the current angle. Specifically, Figure 2 In the example, the current vector angle in the two-phase stationary coordinate system can be obtained by adding the rotor position angle and the current angle. In other words, the current vector angle is equal to the sum of the rotor position angle and the current angle.

[0059] Further, in Figure 2 In the example, after the voltage compensation module 23 calculates the current vector angle in the two-phase stationary coordinate system, it can determine the first compensation amount and the second compensation amount according to the current vector angle, and compensate the α-axis reference voltage Uα in the two-phase stationary coordinate system with the first compensation amount, and compensate the β-axis reference voltage Uβ in the two-phase stationary coordinate system with the second compensation amount, thereby compensating for the torque pulsation caused by the three-phase inverter of the power-assisted motor during the dead time.

[0060] Optionally, in some embodiments of the present invention, the step S3 of determining the first compensation amount and the second compensation amount according to the current vector angle includes: step S31, determining a first compensation coefficient and a second compensation coefficient according to the current vector angle, the values ​​of the first compensation coefficient and the second compensation coefficient corresponding one-to-one to the current vector angle interval in which the current vector angle is located; step S32, calculating and determining the first compensation amount according to the first compensation coefficient, and determining the second compensation amount according to the second compensation coefficient.

[0061] For details, please combine Figure 3 , Figure 4 And the following Table 1, in one embodiment of the present invention, the voltage compensation module 23 or the power assist motor control device 20 may be provided with a memory, and the memory pre-stores a mapping table of current vector angle intervals and compensation coefficients shown in Table 1, and the mapping table includes the correspondence between the current vector angle intervals, the three-phase current directions, the first compensation coefficient (K1) and the second compensation coefficient (K2).

[0062] Table 1 Mapping table of current vector angle interval and compensation coefficient

[0063]

[0064] It can be seen from Table 1 that when the current vector angle is in any of the current vector angle intervals, the first compensation coefficient and the second compensation coefficient are correspondingly preset, and the first compensation coefficient and the second compensation coefficient are correspondingly obtained according to the current vector angle interval that the current vector angle is currently in. Therefore, in this embodiment, after the voltage compensation module 23 calculates the current vector angle in the two-phase stationary coordinate system, the first compensation coefficient and the second compensation coefficient can be determined according to the mapping table pre-stored in the memory.

[0065] Further, such as Figure 3 As shown, in this embodiment, the compensation amplitude of the current vector angle interval U1comp to U6comp is Td*Udc / Ts, where Td is the dead time of the power-assisted motor, Udc is the bus voltage of the power-assisted motor, and Ts is the carrier period of the power-assisted motor. In this way, the first compensation amount is defined as U1, and the second compensation amount is defined as U2. The first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship: U1=K1*Td*Udc / Ts, U2=K2*Td*Udc / Ts.

[0066] It is not difficult to understand that in this embodiment, after determining the first compensation coefficient and the second compensation coefficient according to the current vector angle and the mapping table, and further calculating the corresponding first compensation amount and the second compensation amount according to the corresponding relationship, the α-axis reference voltage Uα and the β-axis reference voltage Uβ in the two-phase stationary coordinate system can be directly compensated (see Figure 4 ), compared with the prior art of compensating the three-phase voltage separately, the compensation scheme of this embodiment simplifies the compensation steps and is also convenient for development based on different power-assisted motor models. Figure 5 and Figure 6 , compared with the current waveform curve diagram of the output current of the booster motor 10 before compensation of the α-axis reference voltage Uα and the β-axis reference voltage Uβ (see Figure 5 ), in the embodiment of the present invention, the output current of the booster motor 10 is a schematic diagram of a current waveform curve after the α-axis reference voltage Uα and the β-axis reference voltage Uβ are compensated (see Figure 6 ) is significantly improved, effectively suppressing the output waveform distortion of the output current.

[0067] Also optionally, in some other embodiments of the present invention, the current vector angle is defined as θ, the current vector angle corresponding to any phase current in the three-phase current passing through the zero point is defined as a mutation angle θ', the preset optimization angle is defined as δ, and the step S3 of determining the first compensation amount and the second compensation amount according to the current vector angle includes the following two steps:

[0068] When the current vector angle is in a current vector angle interval outside the mutation interval, the first compensation coefficient and the second compensation coefficient are determined according to the current vector angle, and the first compensation amount is further calculated and determined according to the first compensation coefficient, and the second compensation amount is determined according to the second compensation coefficient. Wherein, the mutation interval is the vector angle interval corresponding to (θ'±δ), and the values ​​of the first compensation coefficient and the second compensation coefficient correspond to the current vector angle interval in which the current vector angle is located. For specific corresponding relationships, please refer to the aforementioned mapping table 1, and the first compensation amount is calculated and determined according to the first compensation coefficient, and the second compensation amount is determined according to the second compensation coefficient, which can be calculated by referring to the aforementioned two relationship formulas (i.e., U1=K1*Td*Udc / Ts, U2=K2*Td*Udc / Ts). For more details, please refer to the aforementioned related content, which will not be repeated here.

[0069] When the current vector angle is in the mutation interval, the third compensation coefficient is determined according to the current vector angle, the mutation angle, the preset optimization angle and the first linearization equation, and the fourth compensation coefficient is determined according to the current vector angle, the mutation angle, the preset optimization angle and the second linearization equation, and the first compensation amount is further calculated and determined according to the third compensation coefficient, and the second compensation amount is determined according to the fourth compensation coefficient. Wherein, the first linearization equation is the linearization equation corresponding to the current vector angle being in the vector angle interval of (θ'+δ), and the second linearization equation is the linearization equation corresponding to the current vector angle being in the vector angle interval of (θ'-δ), and the first linearization equation is different from the second linearization equation.

[0070] Considering that when the current crosses the zero point (i.e., the voltage mutation point), the fluctuation of the sampled current and the sampling error will cause the sampled current angle to be inaccurate, and then the calculated current vector angle to be inaccurate. If the compensation coefficient is still determined based on the current vector angle and the mapping table, it will inevitably lead to an error in the compensation amount determined based on the compensation coefficient. Therefore, in another embodiment of the present invention, when the current vector angle is in the mutation interval, the third compensation coefficient and the fourth compensation coefficient are determined respectively based on the current vector angle, the mutation angle, the preset optimization angle and the corresponding first linearization equation and the second linearization equation, so as to perform linearization processing near the current vector angle corresponding to the current zero point (i.e., the voltage mutation point) (see Figure 7 ), the accuracy of determining the compensation coefficient can be improved, so that the first compensation amount and the second compensation amount can be accurately determined, avoiding the risk of incorrect compensation amount calculation caused by incorrect current angle judgment at the voltage mutation point, and avoiding the introduction of additional harmonics due to incorrect compensation amount.

[0071] Specifically, in another embodiment of the present invention, when the current vector angle is in the mutation interval, the first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship:

[0072]

[0073] The value of the preset optimization angle δ is less than or equal to 10 degrees, and there is no limitation on this.

[0074] It can be understood that in other embodiments of the present invention, when the current vector angle is in the mutation interval, other compensation methods can also be used to optimize the current vector angle corresponding to the voltage mutation point, such as but not limited to compensation in the form of a tangent function. Specifically, before the current vector angle corresponding to each voltage mutation point arrives, the compensation amount is multiplied by a gain in the form of a tangent function to rapidly reduce the compensation amount. After the current vector angle crosses the mutation point, the compensation amount increases rapidly. In this way, the compensated α-axis reference voltage Uα and β-axis reference voltage Uβ voltages can be obtained more accurately.

[0075] It should be noted that, in the embodiment of the present invention, the voltage compensation module 23 compensates the α-axis reference voltage Uα and the β-axis reference voltage Uβ of the power-assisted motor 10 in the two-phase stationary coordinate system, which can be achieved through the SVPWM module. The specific implementation principle is the existing technology and will not be described in detail. In addition, similar to the existing power-assisted motor control device, the power-assisted motor control device 20 can also include other module components, such as but not limited to a motor speed calculation module, a current calculation module, a current PI module, a temperature detection module, etc., which will not be described in detail.

[0076] Furthermore, an embodiment of the present invention provides a power-assisted motor control device, comprising a memory and a processor connected to the memory, wherein the memory stores a computer program executable by the processor. When the processor executes the computer program, the power-assisted motor control method described in any of the above embodiments can be implemented. For details, please refer to the relevant description in the aforementioned method embodiment.

[0077] Furthermore, an embodiment of the present invention provides a vehicle, which includes the power-boosting motor control system 100 in the above embodiment, wherein the power-boosting motor control system 100 includes a power-boosting motor 10 and a power-boosting motor control device 20 connected to the power-boosting motor 10, and the power-boosting motor control device 20 is used to execute the power-boosting motor control method provided in the embodiment of the present invention to control the power-boosting motor 10, thereby effectively suppressing the torque pulsation of the power-boosting motor 10.

[0078] The vehicle may be any existing fuel vehicle, electric vehicle or the like, without limitation.

[0079] Furthermore, an embodiment of the present invention provides a readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the power assist motor control method as described in any of the above embodiments is implemented. For details, please refer to the relevant description in the aforementioned method embodiment.

[0080] In the description of the present invention, the description with reference to the terms "embodiment", "specific embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0081] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for controlling a power assist motor, characterized in that: include: Obtain the rotor position angle and the dq axis current in the two-phase rotating coordinate system; Calculating a current angle in a two-phase rotating coordinate system according to the dq axis current, and calculating a current vector angle in a two-phase stationary coordinate system according to the rotor position angle and the current angle; as well as Determining a first compensation amount and a second compensation amount according to the current vector angle, and compensating the α-axis reference voltage Uα in the two-phase stationary coordinate system by the first compensation amount, and compensating the β-axis reference voltage Uβ in the two-phase stationary coordinate system by the second compensation amount, so as to compensate for an output voltage error of the three-phase inverter of the power assist motor during a dead time, thereby suppressing a torque pulsation caused by the output voltage error of the three-phase inverter during the dead time; The current vector angle changes sequentially in a plurality of current vector angle intervals, and the values ​​of the first compensation amount and the second compensation amount correspond one-to-one to the current vector angle interval in which the current vector angle is located.

2. The power assist motor control method according to claim 1, characterized in that: Determining a first compensation amount and a second compensation amount according to the current vector angle includes: Determine a first compensation coefficient and a second compensation coefficient according to the current vector angle, wherein the values ​​of the first compensation coefficient and the second compensation coefficient correspond one-to-one to the current vector angle interval in which the current vector angle is located; The first compensation amount is calculated and determined according to the first compensation coefficient, and the second compensation amount is determined according to the second compensation coefficient.

3. The power assist motor control method according to claim 2, characterized in that: The first compensation amount is defined as U1, and the second compensation amount is defined as U2. The first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship: U1=K1*Td*Udc / Ts, U2=K2*Td*Udc / Ts; Among them, Td is the dead time of the power-assisted motor, Udc is the bus voltage of the power-assisted motor, Ts is the carrier period of the power-assisted motor, K1 and K2 are respectively the first compensation coefficient and the second compensation coefficient, and when the current vector angle is in any of the current vector angle intervals, there is a corresponding preset first compensation coefficient and the second compensation coefficient, and the first compensation coefficient and the second compensation coefficient are obtained according to the current vector angle interval in which the current vector angle is currently located.

4. The power assist motor control method according to claim 1, characterized in that: The current vector angle is defined as θ, the current vector angle corresponding to any phase current in the three-phase current passing through the zero point is defined as the mutation angle θ', and the preset optimization angle is defined as δ; Determining a first compensation amount and a second compensation amount according to the current vector angle includes: When the current vector angle is in a current vector angle interval outside the mutation interval, determining a first compensation coefficient and a second compensation coefficient according to the current vector angle, and further calculating and determining the first compensation amount according to the first compensation coefficient, and determining the second compensation amount according to the second compensation coefficient; When the current vector angle is in the mutation interval, a third compensation coefficient is determined according to the current vector angle, the mutation angle, the preset optimization angle and the first linearization equation, and a fourth compensation coefficient is determined according to the current vector angle, the mutation angle, the preset optimization angle and the second linearization equation, and the first compensation amount is further calculated and determined according to the third compensation coefficient, and the second compensation amount is determined according to the fourth compensation coefficient; Among them, the mutation interval is the vector angle interval corresponding to (θ'±δ), the values ​​of the first compensation coefficient and the second compensation coefficient correspond one-to-one to the current vector angle interval in which the current vector angle is located, the first linearized equation is the linearized equation corresponding to the current vector angle being in the vector angle interval of (θ'+δ), the second linearized equation is the linearized equation corresponding to the current vector angle being in the vector angle interval of (θ'-δ), and the first linearized equation is different from the second linearized equation.

5. The power assist motor control method according to claim 4, characterized in that: The first compensation amount is defined as U1, and the second compensation amount is defined as U2; When the current vector angle is in a current vector angle interval outside the mutation interval, the first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship: U1=K1*Td*Udc / Ts, U2=K2*Td*Udc / Ts When the current vector angle is in the mutation interval, the first compensation amount U1 and the second compensation amount U2 respectively satisfy the relationship: Among them, Td is the dead time of the power-assisted motor, Udc is the bus voltage of the power-assisted motor, and Ts is the carrier period of the power-assisted motor; K1 and K2 are the first compensation coefficient and the second compensation coefficient, respectively. When the current vector angle is in any of the current vector angle intervals, there is a corresponding preset first compensation coefficient and the second compensation coefficient, and the first compensation coefficient and the second compensation coefficient are obtained according to the current vector angle interval in which the current vector angle is currently located.

6. The power assist motor control method according to claim 5, characterized in that: The value of the preset optimization angle δ is less than or equal to 10 degrees.

7. The power assist motor control method according to any one of claims 1 to 6, characterized in that: The current vector angle is equal to the sum of the rotor position angle and the current angle.

8. The power assist motor control method according to any one of claims 1 to 6, characterized in that: Obtain the dq axis current in the two-phase rotating coordinate system, including: The three-phase currents are sampled and converted into dq-axis currents in a two-phase rotating coordinate system.

9. A power assist motor control device, comprising a memory and a processor, wherein the memory stores a computer program executable by the processor, characterized in that: When the processor executes the computer program, the power assist motor control method according to any one of claims 1 to 8 is implemented.

10. A power assist motor control system, characterized in that: It comprises a power-assisting motor and the power-assisting motor control device as claimed in claim 9.

11. A vehicle, characterized in that: It includes the power assist motor control system as claimed in claim 10.

12. A readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the power assist motor control method according to any one of claims 1 to 8 is implemented.

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