A motor controller, its space vector modulation method, and a computer storage medium

Abstract

The present application discloses a motor controller, its space vector modulation method, and a computer storage medium. The method includes the following steps: obtaining a voltage command in the dq coordinate system, and defining the voltage command in the dq coordinate system as the first voltage command; converting the first voltage command into a voltage command in the abc coordinate system, and defining the voltage command in the abc coordinate system as the second voltage command; adding a zero-sequence voltage offset to the second voltage command to translate the second voltage command to the non-negative range to obtain a third voltage command; performing a normalization process on the third voltage command to obtain a normalized voltage vector; and mapping the normalized voltage vector to the duty cycle of PWM modulation. The present application can improve the calculation efficiency of the control algorithm and is more suitable for the real-time control of motors.

Description

Technical Field

[0001] The present application relates to the technical field of motor control, and particularly to a motor controller, a space vector modulation method thereof, and a computer storage medium. Background Art

[0002] SVPWM (Space Vector Pulse Width Modulation) is a technology widely used in motor control, especially most common in three-phase inverters. This technology modulates the three-phase input voltage to generate the required output voltage vector, thereby controlling the speed and torque of the motor. When the existing algorithms perform voltage vector transformation and duty cycle calculation, they calculate through sector division, involving a large number of trigonometric function operations, increasing the calculation burden of the system and resulting in low calculation efficiency of the system. Summary of the Invention

[0003] To solve the deficiencies of the prior art, the present application adopts the following technical solutions:

[0004] In a first aspect, a space vector modulation method for a motor controller provided by the present application includes the following steps:

[0005] Step S11, obtaining a voltage command in the dq coordinate system, and defining the voltage command in the dq coordinate system as a first voltage command;

[0006] Step S12, converting the first voltage command into a voltage command in the abc coordinate system, and defining the voltage command in the abc coordinate system as a second voltage command;

[0007] Step S13, adding a zero-sequence voltage offset to the second voltage command to translate the second voltage command to the non-negative range to obtain a third voltage command;

[0008] Step S14, performing normalization processing on the third voltage command to obtain a normalized voltage vector;

[0009] Step S15, mapping the normalized voltage vector to the duty cycle of PWM modulation.

[0010] In summary, the space vector modulation method for a motor controller provided by the present application simplifies the processing method of the voltage vector, transforms the voltage command from the dq coordinate system to the abc coordinate system, optimizes and adjusts the voltage signal in the abc coordinate system, avoids the traditional sector division step, reduces the operation of trigonometric functions, improves the calculation efficiency of the algorithm, and is more suitable for the real-time control of the motor.

[0011] Further, the method further includes:

[0012] Calculate the minimum value of the normalized voltage vector, perform non - negative processing on the normalized voltage vector based on the minimum value of the normalized voltage vector, and map the non - negatively processed normalized voltage vector to the duty cycle of PWM modulation. After the non - negative processing, the normalized voltage vector satisfies: greater than or equal to 0 and less than or equal to 1.

[0013] Further, the non - negative processing of the normalized voltage vector is represented by the following formula:

[0014] ;

[0015] In the formula, d abc is the normalized voltage vector, d min is the minimum value of the normalized voltage vector, is the non - negatively processed normalized voltage vector.

[0016] Further, adopt a seven - segment space vector modulation method, and the zero - sequence voltage offset satisfies: the action time of zero vector V0 is equal to the action time of zero vector V7.

[0017] Further, the zero - sequence voltage offset value is represented by the following formula:

[0018] ;

[0019] In the formula, U 0 represents the zero - sequence voltage offset value, U abc represents the second voltage command.

[0020] Further, the method further includes:

[0021] Collect three - phase currents and convert the three - phase currents into current values in the dq coordinate system;

[0022] Provide a PI controller and use the current value in the dq coordinate system as the feedback input of the PI controller;

[0023] Compare the feedback input with a preset current command value to obtain a control error, and generate a voltage command in the dq coordinate system based on the control error.

[0024] In a second aspect, a motor controller provided by the present application includes:

[0025] A voltage command acquisition module that acquires a voltage command in the dq coordinate system and defines the voltage command in the dq coordinate system as the first voltage command;

[0026] A coordinate transformation module that converts the first voltage command into a voltage command in the abc coordinate system, and defines the voltage command in the abc coordinate system as the second voltage command;

[0027] A voltage translation module that adds a zero-sequence voltage offset to the second voltage command to shift the second voltage command to the non-negative range to obtain a third voltage command;

[0028] A normalization module that performs normalization processing on the third voltage command to obtain a normalized voltage vector;

[0029] A duty ratio generation module that maps the normalized voltage vector to the duty ratio of PWM modulation;

[0030] A control module that controls the motor based on the duty ratio.

[0031] Further, the normalization module is configured to: calculate the minimum value of the normalized voltage vector, perform non-negative processing on the normalized voltage vector based on the minimum value of the normalized voltage vector, and map the non-negatively processed normalized voltage vector to the duty ratio of PWM modulation, wherein after the non-negative processing, the normalized voltage vector satisfies: greater than or equal to 0 and less than or equal to 1.

[0032] Further, the motor controller adopts a seven-segment space vector modulation method;

[0033] The voltage translation module is configured to: generate a zero-sequence voltage offset value such that the action time of the zero vector V0 is equal to the action time of the zero vector V7.

[0034] In a third aspect, a computer storage medium provided by the present application stores the space vector modulation method of the motor controller described in any one of the above. Description of the Drawings

[0035] Figure 1 It is a step flow chart of the space vector modulation method of the motor controller provided by an embodiment of the present application;

[0036] Figure 2 It is a specific flow chart of step S11 in the space vector modulation method of the motor controller provided by an embodiment of the present application;

[0037] Figure 3 It is a schematic diagram of the switching waveforms of each phase in the seven-segment modulation method of the space vector modulation method of the motor controller provided by an embodiment of the present application;

[0038] Figure 4Schematic diagram of the original three-phase voltage in the abc coordinate system for the space vector modulation method of a motor controller provided by an embodiment of the present application;

[0039] Figure 5 Schematic diagram of the modulated three-phase voltage in the abc coordinate system for the space vector modulation method of a motor controller provided by an embodiment of the present application;

[0040] Figure 6 Schematic diagram of the composition of a motor controller provided by an embodiment of the present application. Detailed implementation manners

[0041] The following will describe the present application in detail in conjunction with the specific implementation manners shown in the accompanying drawings. However, these implementation manners do not limit the present application, and any structural, method, or functional transformation made by those of ordinary skill in the art based on these implementation manners is included in the protection scope of the present application.

[0042] To solve the deficiencies of the prior art, in a first aspect, a space vector modulation method of a motor controller provided by the present application is as Figure 1 shown, and the method includes the following steps:

[0043] Step S11: Obtain the voltage command in the dq coordinate system, and define the voltage command in the dq coordinate system as the first voltage command;

[0044] Step S12: Convert the first voltage command into a voltage command in the abc coordinate system, and define the voltage command in the abc coordinate system as the second voltage command;

[0045] Step S13: Add a zero-sequence voltage offset to the second voltage command to translate the second voltage command to the non-negative range to obtain a third voltage command;

[0046] Step S14: Perform normalization processing on the third voltage command to obtain a normalized voltage vector;

[0047] Step S15: Map the normalized voltage vector to the duty cycle of PWM modulation.

[0048] According to the above description, a space vector modulation method of a motor controller provided by the present application simplifies the processing method of voltage vectors, transforms the voltage command from the dq coordinate system to the abc coordinate system, optimizes and adjusts the voltage signal in the abc coordinate system, avoids the traditional sector division step, reduces the operation of trigonometric functions, improves the calculation efficiency of the algorithm, and is more suitable for the real-time control of motors.

[0049] As an implementation manner, as Figure 2 shown, in step S11, it includes:

[0050] Step S111, collect three-phase currents and convert the three-phase currents into current values in the dq coordinate system;

[0051] Step S112, provide a PI controller and use the current values in the dq coordinate system as the feedback input of the PI controller;

[0052] Step S113, compare the feedback input with a preset current command value to obtain a control error, and generate a voltage command in the dq coordinate system based on the control error.

[0053] Specifically, based on the actual sampling of the three-phase currents of the motor, the sampled three-phase currents are subjected to coordinate transformation and converted into current values in the dq coordinate system. Decoupled control of the motor is achieved in the dq coordinate system, such that the d-axis current is directly related to the torque and the q-axis current is related to the magnetic flux. Provide a PI controller. In the dq coordinate system, the PI controller receives the converted current values as the feedback input and compares the feedback input with the preset current command values (i.e., the desired d-axis and q-axis currents). The PI controller calculates the control error through proportional and integral actions. The PI controller generates a voltage command in the dq coordinate system based on the control error, and defines the voltage command in the dq coordinate system as the first voltage command. The first voltage command can be transformed back from the dq coordinate system to the abc three-phase coordinate system through inverse coordinate transformation, and the first voltage command is used to generate a PWM control signal.

[0054] As an implementation, in step S12, convert the first voltage command into a voltage command in the abc coordinate system, and define the voltage command in the abc coordinate system as the second voltage command.

[0055] Specifically, in this embodiment, the first voltage command is first transformed from the dq coordinate system to the αβ coordinate system, and the formula is expressed as follows:

[0056] (1);

[0057] In the formula, represents the voltage vector in the dq coordinate system, including Ud and Uq; represents the voltage vector in the αβ coordinate system, including Uα and Uβ; represents the transformation matrix from the dq coordinate system to the αβ coordinate system.

[0058] The first voltage command is then transformed from the αβ coordinate system to the abc coordinate system, thereby obtaining the second voltage command in the abc coordinate system. The formula is expressed as follows:

[0059] (2);

[0060] In the formula, represents the voltage vector in the αβ coordinate system, including Uα and Uβ; Represents the voltage vector in the abc coordinate system, including Ua, Ub and Uc; Represents the transformation matrix for inverse transformation from the αβ coordinate system to the abc coordinate system.

[0061] As an implementation method, in step S13, a seven-segment space vector modulation method is adopted, and the zero-sequence voltage offset satisfies: the action time of the zero vector V0 (ie, U0 (000)) is equal to the action time of the zero vector V7 (ie, U7 (111)).

[0062] Specifically, the switching waveforms of each phase of the seven-segment space vector modulation in sector 1 are as follows: Figure 3 As shown, the minimum value of the three-phase command voltage determines the action time T0 of the zero vector V0, and the maximum value of the three-phase command voltage determines the action time T7 of the zero vector. In a carrier cycle of the space vector modulation method, the modulation wave remains constant. According to the volt-second balance principle, it can be obtained:

[0063] (3);

[0064] Where U A Indicates the A phase voltage in the three-phase voltage, U B Indicates the B phase voltage in the three-phase voltage, U C Indicates the C phase voltage in the three-phase voltage, U dc Indicates the DC bus voltage, T s It represents the carrier cycle, T1 represents the time when a switch of the upper bridge arm is turned on in one PWM cycle, T2 represents the time when a switch of the lower bridge arm is turned on in one PWM cycle, and T7 represents the time when all switches of the upper bridge arm are turned on in one PWM cycle.

[0065] According to the above formula (3), we can get:

[0066] (4);

[0067] Where U0 represents the zero-sequence voltage offset value.

[0068] Furthermore, combining the above formulas, it can be obtained that the zero-sequence voltage offset satisfies: the action time of the zero vector V0 is equal to the action time of the zero vector V7, that is, when T0 = T7:

[0069] (5);

[0070] According to the above description, the zero-sequence voltage offset value can be expressed by the following formula:

[0071] (6);

[0072] Wherein, U0 represents the zero-sequence voltage offset value, and U abc represents the second voltage command.

[0073] In the abc coordinate system, the original three-phase voltages are as Figure 4 shown. Based on the above zero-sequence voltage bias, the zero-sequence voltage offset is added to the second voltage command, and the second voltage command is translated to the non-negative range, thereby obtaining the third voltage command, which can be expressed by the following formula:

[0074] (7);

[0075] Wherein, represents the third voltage command, represents the normalized voltage vector, represents the DC bus voltage.

[0076] According to the above description, through the voltage offset compensation mechanism in step S13, the output stability of the voltage under low voltage conditions is effectively improved, and the influence of voltage fluctuations on the system is reduced.

[0077] As an implementation, in step S14, the third voltage command is normalized to obtain the normalized voltage vector. In step S15, the minimum value of the normalized voltage vector is calculated, and the normalized voltage vector is non-negatively processed based on the minimum value of the normalized voltage vector, and the non-negatively processed normalized voltage vector is mapped to the duty cycle of PWM modulation, wherein, after the non-negative processing, the normalized voltage vector satisfies: greater than or equal to 0 and less than or equal to 1.

[0078] Specifically, based on step S14, the minimum value of the normalized voltage vector is calculated, and the normalized zero-sequence voltage offset value is calculated according to the minimum value of the normalized voltage vector, and the normalized voltage vector is non-negatively processed, so that all voltage components are translated downward to ensure that all components are positive and at least 0, thereby ensuring that the normalized voltage vector satisfies: greater than or equal to 0 and less than or equal to 1. Further, the non-negative processing of the normalized voltage vector is expressed by the following formula:

[0079] (8);

[0080] Wherein, d abc is the normalized voltage vector, d min is the minimum value of the normalized voltage vector, is the non-negatively processed normalized voltage vector, and d0 represents the normalized zero-sequence voltage offset value.

[0081] According to the above description, after the above mathematical processing of the Figure 4 three-phase voltages, the space vector modulation drive waveform obtained is asFigure 5 As shown. The output period of the PWM modulation signal is determined by the timer. The counting period is set as PWMPRD, that is, when the timer counts from 0 to PWMPRD, it represents a complete PWM modulation period. Then the duty cycle calculation can be expressed by the following formula:

[0082] (9);

[0083] In the formula, PWMPRD represents the calculation period of PWM modulation, and PWMPRD is used to generate the PWM comparison value. represents the duty cycle.

[0084] According to the above description, a space vector modulation method for a motor controller provided by the present application simplifies the processing method of voltage vectors, transforms the voltage command from the dq coordinate system to the abc coordinate system, optimizes and adjusts the voltage signal in the abc coordinate system, avoids the traditional sector division steps, reduces the operation of trigonometric functions, improves the calculation efficiency of the algorithm, and is more suitable for the real-time control of motors; and, through the voltage offset compensation mechanism, effectively improves the output stability of the voltage under low voltage conditions and reduces the influence of voltage fluctuations on the system.

[0085] In the second aspect, the present application provides a motor controller, as Figure 6 shown. The motor controller includes a voltage command acquisition module, a coordinate conversion module, a voltage translation module, a normalization module, a duty cycle generation module, and a control module.

[0086] Specifically, the voltage command acquisition module is configured to acquire the voltage command in the dq coordinate system, and define the voltage command in the dq coordinate system as the first voltage command; the coordinate conversion module is configured to convert the first voltage command into the voltage command in the abc coordinate system, and define the voltage command in the abc coordinate system as the second voltage command; the voltage translation module is configured to add a zero-sequence voltage offset to the second voltage command to translate the second voltage command to the non-negative range to obtain a third voltage command; the normalization module is configured to perform normalization processing on the third voltage command to obtain a normalized voltage vector; the duty cycle generation module is configured to map the normalized voltage vector to the duty cycle of PWM modulation; the control module is configured to control the motor based on the duty cycle.

[0087] In the coordinate conversion module, the first voltage command is converted into the voltage command in the abc coordinate system, and the voltage command in the abc coordinate system is defined as the second voltage command.

[0088] Specifically, in the coordinate conversion module, the first voltage command is first transformed from the dq coordinate system to the αβ coordinate system, and the formula is expressed as follows:

[0089] (10);

[0090] In the formula, represents the voltage vector in the dq coordinate system, including Ud and Uq; represents the voltage vector in the αβ coordinate system, including Uα and Uβ; represents the transformation matrix from the dq coordinate system to the αβ coordinate system.

[0091] The first voltage command is then transformed from the αβ coordinate system to the abc coordinate system to obtain the second voltage command in the abc coordinate system. The formula is expressed as follows:

[0092] (11);

[0093] In the formula, represents the voltage vector in the αβ coordinate system, including Uα and Uβ; represents the voltage vector in the abc coordinate system, including Ua, Ub, and Uc; represents the transformation matrix for the inverse transformation from the αβ coordinate system to the abc coordinate system.

[0094] According to the above description, a motor controller provided by the present application transforms the voltage command from the dq coordinate system to the abc coordinate system, optimizes and adjusts the voltage signal in the abc coordinate system, reduces the operation of trigonometric functions, improves the calculation efficiency of the algorithm, and is more suitable for the real-time control of the motor; it also simplifies the processing method of the voltage vector, avoids the traditional sector division step, and further improves the calculation efficiency of the algorithm; and, through the voltage offset compensation mechanism, effectively improves the output stability of the voltage under low voltage conditions and reduces the impact of voltage fluctuations on the system.

[0095] Further, as an implementation, the normalization module is further configured to: calculate the minimum value of the normalized voltage vector, and perform non-negative processing on the normalized voltage vector based on the minimum value of the normalized voltage vector, and map the non-negatively processed normalized voltage vector to the duty cycle of PWM modulation, where, after the non-negative processing, the normalized voltage vector satisfies: greater than or equal to 0 and less than or equal to 1.

[0096] Specifically, calculate the minimum value of the normalized voltage vector, calculate the normalized zero-sequence voltage offset value according to the minimum value of the normalized voltage vector, and perform non-negative processing on the normalized voltage vector, so that all voltage components are shifted downward to ensure that all components are positive and at least 0, so as to ensure that the normalized voltage vector satisfies: greater than or equal to 0 and less than or equal to 1. Further, the non-negative processing of the normalized voltage vector is expressed by the following formula:

[0097] (12);

[0098] Where d abc is the normalized voltage vector, and d min is the minimum value of the normalized voltage vector, is the normalized voltage vector after non - negative processing.

[0099] The output period of the PWM modulation signal is determined by the timer. The counting period is set as PWMPRD. That is, when the timer counts from 0 to PWMPRD, it represents a complete PWM modulation period. Then the duty cycle calculation can be expressed by the following formula:

[0100] (13);

[0101] Where PWMPRD represents the calculation period of PWM modulation, and PWMPRD is used to generate the PWM comparison value, represents the duty cycle.

[0102] As an implementation manner, the motor controller provided by this application adopts a seven - segment space vector modulation method; the voltage translation module is configured to: generate a zero - sequence voltage offset value such that the action time of the zero - vector V0 is equal to the action time of the zero - vector V7.

[0103] Specifically, the minimum value of the three - phase command voltage determines the action time T0 of the zero - vector V0, and the maximum value of the three - phase command voltage determines the action time of the zero - vector T7. In a carrier period of the space vector modulation method, the modulation wave remains constant. According to the volt - second balance principle, we can obtain:

[0104] (14);

[0105] Where U A represents the A - phase voltage in the three - phase voltage, U B represents the B - phase voltage in the three - phase voltage, U C represents the C - phase voltage in the three - phase voltage, U dc represents the DC bus voltage, T s represents the carrier period, T1 represents the conduction time of one switch in the upper bridge arm in a PWM period, T2 represents the conduction time of one switch in the lower bridge arm in a PWM period, and T7 represents the conduction time of all switches in the upper bridge arm in a PWM period.

[0106] Solving according to the above formula (14):

[0107] (15);

[0108] Where U0 represents the zero - sequence voltage offset value.

[0109] Furthermore, combining the above formulas, it can be obtained that the zero-sequence voltage offset satisfies: the action time of the zero vector V0 is equal to the action time of the zero vector V7, that is, when T0 = T7:

[0110] (16);

[0111] According to the above description, the zero-sequence voltage offset value can be expressed by the following formula:

[0112] (17);

[0113] Where U0 represents the zero-sequence voltage offset value, U abc Indicates the second voltage command.

[0114] In the abc coordinate system, the original three-phase voltage is as follows Figure 4 As shown, based on the above zero-sequence voltage bias, a zero-sequence voltage offset is added to the second voltage instruction, and the second voltage instruction is translated to a non-negative range, thereby obtaining a third voltage instruction, which can be expressed by the following formula:

[0115] (18);

[0116] In the formula, Indicates the third voltage instruction, represents the normalized voltage vector, Indicates the bus DC voltage.

[0117] According to the above description, a motor controller provided by the present application simplifies the processing method of the voltage vector, transforms the voltage command from the dq coordinate system to the abc coordinate system, optimizes and adjusts the voltage signal in the abc coordinate system, avoids the traditional sector division steps, reduces the calculation of trigonometric functions, improves the computational efficiency of the algorithm, and is more suitable for real-time control of the motor; and, through the voltage offset compensation mechanism, effectively improves the output stability of the voltage under low voltage conditions, and reduces the impact of voltage fluctuations on the system.

[0118] In a third aspect, the present application also provides a computer storage medium, which stores the space vector modulation method of the motor controller described above, which is used to improve the computational efficiency of the motor controller and improve the output stability of the motor system under low voltage.

[0119] It will be understood that the term "exemplary" as used herein means "serving as an example, instance, or illustration". Any embodiment described as "exemplary" is not necessarily preferred or superior to other embodiments and / or does not preclude the combination of features with other embodiments. It should be understood that certain features of the present application that are described in the context of separate embodiments for clarity may also be provided in a single embodiment by combination. Conversely, the various features of the present application that are described in the context of a single embodiment for clarity may also be provided separately or in any suitable combination or as any other described embodiment of the present application.

[0120] The foregoing disclosure is only the preferred embodiment of the present application, but it is not used to limit the scope of the rights of the present application. Those of ordinary skill in the art can understand that within the spirit and scope of the present application and the appended claims, changes, modifications, substitutions, combinations, and simplifications should all be equivalent replacement methods and still fall within the scope covered by the invention.

Claims

1. A space vector modulation method for a motor controller, characterized in that: The method comprises the following steps: Acquire a voltage command in a dq coordinate system, and define the voltage command in the dq coordinate system as a first voltage command; Convert the first voltage instruction into a voltage instruction in an abc coordinate system, and define the voltage instruction in the abc coordinate system as a second voltage instruction; adding a zero-sequence voltage offset to the second voltage command so as to shift the second voltage command to a non-negative range to obtain a third voltage command; Normalizing the third voltage command to obtain a normalized voltage vector; Mapping the normalized voltage vector to a duty cycle of PWM modulation; The method further comprises: The minimum value of the normalized voltage vector is calculated, and the normalized voltage vector is non-negatively processed based on the minimum value of the normalized voltage vector. After the non-negative processing, the normalized voltage vector satisfies: greater than or equal to 0, and less than or equal to 1. The non-negative processing of the normalized voltage vector is expressed by the following formula: ； In the formula, d abc is the normalized voltage vector, d min is the minimum value of the normalized voltage vector, is the normalized voltage vector after non-negative processing; The non-negative processed normalized voltage vector is mapped to the duty cycle of PWM modulation. The output period of the PWM modulation signal is determined by the timer. The counting period is set to PWMPRD. The timer counts from 0 to PWMPRD to represent a complete PWM modulation period. The duty cycle calculation is expressed by the following formula: ; Where PWMPRD represents the calculation period of PWM modulation, and PWMPRD is used to generate PWM comparison value. represents the duty cycle, and Uabc represents the second voltage instruction.

2. The space vector modulation method of the motor controller according to claim 1, characterized in that: The method further comprises: A seven-segment space vector modulation method is adopted, and the zero-sequence voltage offset satisfies: the action time of the zero vector V0 is equal to the action time of the zero vector V7.

3. The space vector modulation method of the motor controller according to claim 2, characterized in that: The zero-sequence voltage offset value is expressed by the following formula: ； In the formula, U 0 represents the zero-sequence voltage offset value, U abc represents the second voltage instruction.

4. The space vector modulation method of the motor controller according to claim 1, characterized in that: The method further comprises: Collecting three-phase currents and converting the three-phase currents into current values ​​in a dq coordinate system; Providing a PI controller, and using the current value in the dq coordinate system as a feedback input of the PI controller; The feedback input is compared with a preset current command value to obtain a control error, and a voltage command in the dq coordinate system is generated based on the control error.

5. A motor controller, characterized in that: The motor controller comprises: a voltage instruction acquisition module, which acquires a voltage instruction in a dq coordinate system and defines the voltage instruction in the dq coordinate system as a first voltage instruction; A coordinate conversion module, converting the first voltage instruction into a voltage instruction in an abc coordinate system, and defining the voltage instruction in the abc coordinate system as a second voltage instruction; a voltage shift module, adding a zero-sequence voltage offset to the second voltage instruction, so as to shift the second voltage instruction to a non-negative range, so as to obtain a third voltage instruction; a normalization module, performing normalization processing on the third voltage instruction to obtain a normalized voltage vector; The normalization module is configured to: calculate a minimum value of a normalized voltage vector, and perform non-negative processing on the normalized voltage vector based on the minimum value of the normalized voltage vector, wherein after the non-negative processing, the normalized voltage vector satisfies: greater than or equal to 0, and less than or equal to 1; The duty cycle generation module maps the normalized voltage vector after non-negative processing to the duty cycle of PWM modulation. The output period of the PWM modulation signal is determined by the timer. The counting period is set to PWMPRD. The timer counts from 0 to PWMPRD to represent a complete PWM modulation period. The duty cycle calculation is expressed by the following formula: ； Where PWMPRD represents the calculation period of PWM modulation, and PWMPRD is used to generate PWM comparison value. represents the duty cycle, and Uabc represents the second voltage instruction; A control module controls the motor based on the duty cycle.

6. The motor controller according to claim 5, characterized in that: The motor controller adopts a seven-segment space vector modulation method; The voltage translation module is configured to generate a zero-sequence voltage offset value so that the zero-sequence voltage offset value satisfies: an action time of the zero vector V0 is equal to an action time of the zero vector V7.

7. A computer storage medium, characterized in that: The medium stores the space vector modulation method of the motor controller as described in any one of claims 1 to 4.

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