A dead-time voltage compensation method and system for permanent magnet synchronous motor

Abstract

The application discloses a dead-zone voltage compensation method and system for a permanent magnet synchronous motor, and comprises the following steps: obtaining three-phase input currents of the permanent magnet synchronous motor in real time, and obtaining current components in a five-order rotating reference frame based on the three-phase input currents; performing low-pass filtering on the current components in the five-order rotating reference frame to obtain five-order harmonic current components; obtaining an injection amplitude and phase for dead-zone voltage compensation according to a cross-coupling processing result of the five-order harmonic current components and in combination with a real-time electric angle of the permanent magnet synchronous motor, and compensating the injection amplitude and phase into inverter driving signals in a PMSM original controller. The application eliminates all orders of harmonic currents caused by dead-zone time, improves the dead-zone compensation effect, and reduces the complexity and calculation amount of the system.

Description

Technical Field

[0001] This invention relates to the field of PMSM dead-zone compensation technology, and in particular to a dead-zone voltage compensation method and system for permanent magnet synchronous motors. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) are characterized by simple structure, high power density, strong overload capacity, and easy maintenance, and have been widely used in industrial robots, electric vehicles, aerospace and other fields.

[0003] PMSMs are typically driven by a three-phase full-bridge circuit based on insulated-gate bipolar transistors (IGBTs). In pulse-width modulation (PWM) PMSM drive controllers, dead time needs to be inserted into the switching signals to prevent the upper and lower transistors of the same bridge arm of the inverter from conducting simultaneously. However, dead time introduces harmonics into the inverter output voltage, leading to current waveform distortion and torque ripple. The dead time effect also reduces the stability and control performance of the driver.

[0004] In the existing technology, most of the existing methods for solving the dead zone effect require additional external circuits or depend on motor parameters, which leads to computational complexity and the inability to eliminate all order harmonics. Summary of the Invention

[0005] The purpose of this invention is to provide a dead-zone compensation scheme that can eliminate all dead-zone-related harmonics without requiring any additional hardware.

[0006] To address the aforementioned technical problems, this invention provides a method for dead-zone voltage compensation in a permanent magnet synchronous motor (PMSM), comprising: obtaining the three-phase input current of the PMSM in real time, and based on this, obtaining the current component in a fifth rotating reference frame; performing low-pass filtering on the current component in the fifth rotating reference frame to obtain the fifth harmonic current component; and, based on the cross-coupling processing result of the fifth harmonic current component and combined with the real-time electrical angle of the PMSM, obtaining the injection amplitude and phase for dead-zone voltage compensation, and compensating them into the inverter drive signal within the original PMSM controller.

[0007] Preferably, the process of obtaining the current components in the five-fold rotating reference frame includes: sequentially passing the real-time three-phase input current of the permanent magnet synchronous motor through Clark transformation and Park transformation to obtain the current components in the dq synchronous reference frame; and obtaining the current components in the five-fold rotating reference frame through multiple synchronous rotating coordinate transformations based on the current components in the dq synchronous reference frame.

[0008] Preferably, the multi-synchronous rotation coordinate transformation process is implemented using the following transformation matrix:

[0009]

[0010] in, ω represents the multiple synchronous rotating coordinate transformation matrix, ω represents the synchronous rotational speed, and t represents time.

[0011] Preferably, the step of obtaining the injection amplitude and phase for dead-zone voltage compensation based on the cross-coupling processing result of the fifth harmonic current components and the real-time electrical angle of the permanent magnet synchronous motor, and compensating them into the inverter drive signal in the original controller of the PMSM, includes: performing addition and subtraction processing on the fifth harmonic current components respectively, then adjusting the addition calculation result using a first PI control controller to obtain the amplitude of the equivalent dead time, and adjusting the subtraction calculation result using a second PI control controller to obtain the phase for adjusting the dead-zone compensation injection; and obtaining the dead-zone compensation signal and compensation electrical angle for dead-zone compensation using a preset dead-zone compensation strategy based on the amplitude of the equivalent dead time, the phase for adjusting the dead-zone compensation injection, and the real-time electrical angle.

[0012] Preferably, the preset dead-zone compensation strategy is represented by the following expression:

[0013]

[0014] in, This represents the amplitude of the equivalent dead time. This indicates the phase used for adjusting dead-zone compensation injection. This indicates the three-phase dead-time compensation signal added to the existing three-phase duty cycle. θ represents the compensation electrical angle. e Indicates the real-time electrical angle. This indicates the angle by which the current leads the q-axis in the dq synchronous reference frame.

[0015] Preferably, the amplitude of the equivalent dead time and the phase used for adjusting dead time compensation injection are calculated using the following expressions:

[0016]

[0017] Among them, K p1 K p2 K represents the proportional coefficient of the first and second PI controllers, respectively. I1 K I2 i represents the integral coefficients of the first and second PI controllers, respectively. d5 i q5These respectively represent the fifth harmonic current components. This represents the amplitude of the equivalent dead time. This indicates the phase used for adjusting dead zone compensation injection.

[0018] On the other hand, embodiments of the present invention provide a computer-readable storage medium comprising a series of instructions for performing the steps of the method described above.

[0019] In addition, this embodiment of the invention also provides a dead-zone voltage compensation system for a permanent magnet synchronous motor, comprising: a rotating reference frame current component generation module configured to obtain the three-phase input current of the permanent magnet synchronous motor in real time, and based on this, obtain the current component in the fifth rotating reference frame; a rotating reference frame harmonic current component generation module configured to perform low-pass filtering on the current component in the fifth rotating reference frame to obtain the fifth harmonic current component; and a compensation signal generation module configured to obtain the injection amplitude and phase for dead-zone voltage compensation based on the cross-coupling processing result of the fifth harmonic current component and combined with the real-time electrical angle of the permanent magnet synchronous motor, and compensate it into the inverter drive signal in the original controller of the PMSM.

[0020] Preferably, the rotating reference frame current component generation module includes: a synchronous reference frame current component generation unit, configured to sequentially pass the real-time three-phase input current of the permanent magnet synchronous motor through Clark transformation and Park transformation to obtain the current component in the dq synchronous reference frame; and a multi-synchronous rotation processing unit, configured to obtain the current component in the fifth rotating reference frame through multi-synchronous rotation coordinate transformation based on the current component in the dq synchronous reference frame.

[0021] Preferably, the compensation signal generation module includes: a compensation time parameter generation unit, configured to add and subtract the fifth harmonic current components respectively, then adjust the addition result using a first PI control controller to obtain the amplitude of the equivalent dead time, and adjust the subtraction result using a second PI control controller to obtain the phase for adjusting the dead time compensation injection; and a compensation signal generation unit, configured to obtain a dead time compensation signal and a compensation electrical angle for dead time compensation based on the amplitude of the equivalent dead time, the phase for adjusting the dead time compensation injection, and the real-time electrical angle, using a preset dead time compensation strategy.

[0022] Compared with the prior art, one or more embodiments of the above solutions may have the following advantages or beneficial effects:

[0023] This invention proposes a method and system for dead-time voltage compensation in permanent magnet synchronous motors. Firstly, this invention can estimate the equivalent dead time and its phase without needing to know the motor parameters or require additional hardware circuitry. It adjusts the amplitude and phase of the compensation for the anti-dead time by using the sum and difference of the dq harmonic currents in a five-order rotating reference frame. Secondly, the polarity switching of the compensation time in this invention is based on electrical angles, which are more stable than determining the polarity of the measured current. Finally, by processing the fifth-order harmonic current, this invention eliminates all orders of harmonic currents caused by the dead time, not only improving the dead-time compensation effect but also reducing the system complexity and computational load.

[0024] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0026] Figure 1 This is a schematic diagram illustrating the steps of a dead-zone voltage compensation method for a permanent magnet synchronous motor according to an embodiment of this application.

[0027] Figure 2 This is a schematic diagram illustrating the implementation principle of the dead-zone voltage compensation method for permanent magnet synchronous motors according to an embodiment of this application.

[0028] Figure 3 This is a block diagram of a dead-zone voltage compensation system for a permanent magnet synchronous motor according to an embodiment of this application. Detailed Implementation

[0029] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and examples, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that, as long as there is no conflict, the various embodiments and features in the various embodiments of the present invention can be combined with each other, and the resulting technical solutions are all within the protection scope of the present invention.

[0030] Furthermore, the steps illustrated in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Also, although a logical order is shown in the flowcharts, in some cases the steps shown or described may be performed in a different order than that shown here.

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms “a” and “an” as used herein are also intended to include the plural. It should also be understood that the terms “comprising” and / or “including” as used herein specify the presence of the stated features, integers, steps, operations, units, and / or components, without excluding the presence or addition of one or more other features, integers, steps, operations, units, components, and / or combinations thereof.

[0032] Permanent magnet synchronous motors (PMSMs) are characterized by simple structure, high power density, strong overload capacity, and easy maintenance, and have been widely used in industrial robots, electric vehicles, aerospace and other fields.

[0033] PMSMs are typically driven by a three-phase full-bridge circuit based on insulated-gate bipolar transistors (IGBTs). In pulse-width modulation (PWM) PMSM drive controllers, dead time needs to be inserted into the switching signals to prevent the upper and lower transistors of the same bridge arm of the inverter from conducting simultaneously. However, dead time introduces harmonics into the inverter output voltage, leading to current waveform distortion and torque ripple. The dead time effect also reduces the stability and control performance of the driver.

[0034] In the existing technology, most of the existing methods for solving the dead zone effect require additional external circuits or depend on motor parameters, which leads to computational complexity and the inability to eliminate all order harmonics.

[0035] To address the technical problems mentioned above, this application proposes a dead-zone voltage compensation method and system for permanent magnet synchronous motors (PMSMs) based on a cross-coupling algorithm. Specifically, it includes: real-time measurement of the electrical angle and three-phase current of the PMSM; and obtaining the current components in two fifth-order rotating reference frames through multiple synchronous rotating coordinate system transformations. and The current components in the two fifth-order rotating reference frames are filtered using a low-pass filter (LPF) to obtain the fifth-order harmonic current components i in the two fifth-order rotating reference frames. d5 and i q5 Voltage compensation is performed using a dead-time compensation strategy based on cross-coupling. This invention does not require additional detection circuitry or current polarity determination algorithms; it only requires a 5th-order harmonic extractor and two PI controllers to eliminate all dead-time-related harmonics, thus having a low computational load.

[0036] Figure 1 This is a schematic diagram illustrating the steps of a dead-zone voltage compensation method for a permanent magnet synchronous motor according to an embodiment of this application. Figure 2 This is a schematic diagram illustrating the implementation principle of the dead-zone voltage compensation method for permanent magnet synchronous motors according to an embodiment of this application. The following is in conjunction with... Figure 1 and Figure 2 The specific steps and implementation principles of the dead-zone voltage compensation method described in the embodiments of the present invention are explained.

[0037] Step S110: Obtain the electrical angle and three-phase input current of the permanent magnet synchronous motor in real time, and obtain the current components in the five-fold rotating reference frame based on the real-time electrical angle and real-time three-phase input current.

[0038] In step S110, firstly, the real-time three-phase input current of the permanent magnet synchronous motor, which is measured in real time, is sequentially subjected to Clark transformation and Park transformation to obtain the current component under the dq synchronous reference frame.

[0039] Specifically, in practical applications, the PMSM is three-phase balanced and half-wave symmetrical. Considering the dead-zone voltage error, the three-phase (input) current is expressed as:

[0040]

[0041] Where I1, I5, and I7 represent the amplitudes of the fundamental, fifth, and seventh harmonic currents of the PMSM, respectively; θ1, θ5, and θ7 represent the phases of the fundamental, fifth, and seventh harmonic currents of the PMSM, respectively; ω represents the synchronous speed; t represents time; and i a i b and i c These represent the three-phase input currents, respectively.

[0042] The real-time three-phase input current of the permanent magnet synchronous motor is transformed by Clark and Park transformations to obtain the current component i in the dq synchronous reference frame. d and i q :

[0043]

[0044] Among them, i d i q This represents the current components in the dq synchronous reference frame. Since the fundamental current is a DC quantity, the fifth and seventh harmonic currents are AC quantities with angular velocities of -6ω and 6ω, respectively.

[0045] Then, based on the current components in the dq synchronous reference frame, the current components in the fifth rotating reference frame are obtained through multiple synchronous rotating coordinate transformations. Specifically, for i d and i qThe current components are transformed to a five-times synchronous reference frame using a multi-synchronous rotating coordinate system transformation. The multi-synchronous rotating coordinate transformation matrix is ​​expressed by the following expression:

[0046]

[0047] in, This represents the multiple synchronous rotating coordinate transformation matrix, where ω represents the synchronous rotational speed (electric angular velocity).

[0048] Furthermore, the current components in the five synchronous reference frames obtained after coordinate transformation are as follows:

[0049]

[0050] in, The current components under the fifth rotating reference frame are obtained separately. Since the fifth harmonic current is a DC quantity, but the first and seventh harmonic components are still AC quantities, it is necessary to proceed to step S120 to use two low-pass filters (LPFs) to obtain the fifth harmonic current components under the fifth rotating reference frame.

[0051] Step S120: Perform low-pass filtering on the current component in the fifth rotating reference frame to obtain the fifth harmonic current component in the fifth rotating reference frame.

[0052] In step S120, the d-axis current components under the five rotating reference frames are... Low-pass filtering is performed using a corresponding low-pass filter (LPF), and the q-axis current component in the fifth rotating reference frame is filtered. A low-pass filter (LPF) is used for low-pass filtering to obtain the fifth harmonic current component i. d5 and i q5 .

[0053] Furthermore, the fifth harmonic current component in the fifth rotating reference frame is:

[0054]

[0055] Among them, i d5 i q5 These represent the fifth harmonic current components in the fifth rotating reference frame.

[0056] Step S130, based on the cross-coupling processing results of the fifth harmonic current components under the fifth rotating reference frame, combined with the real-time electrical angle of the permanent magnet synchronous motor, obtains the injection amplitude and phase for dead zone voltage compensation, and compensates them into the inverter drive signal in the original controller of the PMSM.

[0057] In step S130, firstly, the fifth harmonic current components are added and subtracted respectively. Then, the addition calculation result is adjusted by the first PI control controller to obtain the amplitude of the equivalent dead time (i.e., the amplitude used to adjust the dead time compensation injection). The subtraction calculation result is adjusted by the second PI control controller to obtain the phase used to adjust the dead time compensation injection.

[0058] Specifically, after adding the two fifth-harmonic current components obtained in step S120, the amplitude for adjusting the dead-zone compensation voltage is obtained through the first PI controller; and after subtracting the two fifth-harmonic current components obtained in step S120, the phase for adjusting the dead-zone compensation voltage is obtained through the second PI controller.

[0059]

[0060] Among them, K p1 K p2 K represents the proportional coefficient of the first PI controller and the second PI controller, respectively. I1 K I2 These represent the integral coefficients of the first PI controller and the second PI controller, respectively. This represents the magnitude of the equivalent dead time. This indicates the phase used to adjust the dead zone compensation injection.

[0061] Then, step S130 will also use a preset dead-time compensation strategy to obtain the dead-time compensation signal and compensation electrical angle based on the amplitude of the equivalent dead-time, the phase used to adjust the dead-time compensation injection, and the real-time electrical angle of the current permanent magnet synchronous motor.

[0062] The preset dead-time compensation strategy is represented by the following expression:

[0063]

[0064] in, and These represent the three-phase dead-time compensation signals added to the original three-phase duty cycle (original inverter drive signals). θ represents the compensation electrical angle used to compensate for the real-time electrical angle of the PMSM. e Indicates the real-time electrical angle. This indicates the angle by which the current leads the q-axis in the dq synchronous reference frame.

[0065] Thus, after obtaining the three-phase dead-zone compensation signal and the compensation electrical angle, step S130 of this embodiment of the invention will add the obtained dead-zone compensation signal to the three-phase duty cycle signal output by the SVPWM modulation processing in the original PMSM controller.

[0066] In one embodiment, refer to the following... Figure 2 The working principle of the original PMSM controller is explained. The outer loop is the speed loop, which uses the detected rotational speed ω as feedback; the inner loop is the current loop, which uses current sampling to obtain the stator three-phase current i. a i b and i c Then, through Clark and Park transformations, the stator current i in the dq synchronous reference frame is obtained. d and i q As feedback. Given rotational speed ω * The difference between the measured rotational speed ω and the actual rotational speed ω is used to obtain the setpoint value i of the q-axis stator current via a PI controller. q * The d-axis current given value i d * The value is 0. The difference between the given and measured values ​​of the two current components is passed through a PI controller to obtain the stator voltage u in the dq synchronous reference frame. d and u q The two are transformed by PARK to obtain the stator voltage u in the α-β coordinate system. α and u β This signal is input into the SVPWM to obtain the three-phase duty cycle signal, which is used to control the switching of the inverter transistors, thereby achieving control of the PMSM.

[0067] Based on the aforementioned dead-zone voltage compensation method for permanent magnet synchronous motors, this invention also provides a computer-readable storage medium storing a computer program. Executing the computer program runs a dead-zone voltage compensation method for permanent magnet synchronous motors. The computer program is capable of executing computer instructions, which include computer program code. The computer program code can be in the form of source code, object code, executable files, or certain intermediate forms.

[0068] Computer-readable storage media can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0069] It should be noted that the contents of computer-readable storage media may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, the contents may be appropriately increased or decreased according to the requirements of legislation and patent practice. In other jurisdictions, computer-readable storage media may not include electrical carrier signals and telecommunication signals.

[0070] In addition, based on the above-described method for dead-zone voltage compensation of permanent magnet synchronous motors, this embodiment of the invention also provides a dead-zone voltage compensation system for permanent magnet synchronous motors.

[0071] Figure 3 This is a block diagram of a dead-zone voltage compensation system for a permanent magnet synchronous motor, according to an embodiment of this application. Figure 3 As shown, the dead-zone voltage compensation system of this embodiment includes: a rotating reference frame current component generation module 31, a rotating reference frame harmonic current component generation module 32, and a compensation signal generation module 33.

[0072] Specifically, the rotating reference frame current component generation module 31 is implemented according to the method described in step S110, configured to obtain the three-phase input current of the permanent magnet synchronous motor in real time, and based on this, obtain the current component under the fifth rotating reference frame; the rotating reference frame harmonic current component generation module 32 is implemented according to the method described in step S120, configured to perform low-pass filtering on the current component under the fifth rotating reference frame to obtain the fifth harmonic current component; the compensation signal generation module 33 is implemented according to the method described in step S130, configured to obtain the injection amplitude and phase for dead zone voltage compensation based on the cross-coupling processing result of the fifth harmonic current component and combined with the real-time electrical angle of the permanent magnet synchronous motor, and compensate it into the inverter drive signal in the original controller of the PMSM.

[0073] Furthermore, in one embodiment, the rotating reference frame current component generation module 31 includes: a synchronous reference frame current component generation unit 311 and a multiple synchronous rotation processing unit 312. Specifically, the synchronous reference frame current component generation unit 311 is configured to sequentially pass the real-time three-phase input current of the permanent magnet synchronous motor through Clark transformation and Park transformation to obtain the current component in the dq synchronous reference frame; the multiple synchronous rotation processing unit 312 is configured to obtain the current component in the fifth rotating reference frame based on the current component in the dq synchronous reference frame through multiple synchronous rotation coordinate transformation processing.

[0074] Furthermore, in one embodiment, the compensation signal generation module 33 includes a compensation time parameter generation unit 331 and a compensation signal generation unit 332. Specifically, the compensation time parameter generation unit 331 is configured to perform addition and subtraction processing on the fifth harmonic current components respectively, and then adjust the addition calculation result using a first PI control controller to obtain the amplitude of the equivalent dead time, and adjust the subtraction calculation result using a second PI control controller to obtain the phase used for adjusting the dead time compensation injection; the compensation signal generation unit 332 is configured to obtain the dead time compensation signal and compensation electrical angle for dead time compensation based on the amplitude of the equivalent dead time, the phase used for adjusting the dead time compensation injection, and the real-time electrical angle, using a preset dead time compensation strategy.

[0075] This invention discloses a method and system for dead-time voltage compensation in permanent magnet synchronous motors. This invention can estimate the equivalent dead time and its phase without needing to know the motor parameters or additional hardware circuitry. It adjusts the amplitude and phase of the compensation for the anti-dead time by using the sum and difference of the dq harmonic currents in a five-order rotating reference frame. Secondly, the polarity switching of the compensation time in this invention is based on electrical angles, which are more stable than determining the polarity of the measured current. Finally, by processing the fifth-order harmonic current, this invention eliminates all orders of harmonic currents caused by the dead time, not only improving the dead-time compensation effect but also reducing the system complexity and computational load.

[0076] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0077] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0078] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0079] It should be understood that the embodiments disclosed herein are not limited to the specific structures, processing steps, or materials disclosed herein, but should be extended to equivalent substitutions of these features as understood by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0080] The phrase "an embodiment" or "an embodiment" used in this specification means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Therefore, the phrase "an embodiment" or "an embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0081] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and variations in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection for this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A method for dead-zone voltage compensation in a permanent magnet synchronous motor, characterized in that, include: The three-phase input current of the permanent magnet synchronous motor is obtained in real time, and based on this, the current components under the five-fold rotating reference frame are obtained. The current components in the fifth rotating reference frame are subjected to low-pass filtering to obtain the fifth harmonic current components. Based on the cross-coupling processing results of the fifth harmonic current components, combined with the real-time electrical angle of the permanent magnet synchronous motor, the injection amplitude and phase for dead-zone voltage compensation are obtained, and then compensated into the inverter drive signal in the original controller of the PMSM. This includes: performing addition and subtraction processing on the fifth harmonic current components respectively, then adjusting the addition result using a first PI control controller to obtain the amplitude of the equivalent dead time, and adjusting the subtraction result using a second PI control controller to obtain the phase for adjusting the dead-zone compensation injection. Then, based on the amplitude of the equivalent dead time, the phase for adjusting the dead-zone compensation injection, and the real-time electrical angle, a preset dead-zone compensation strategy is used to obtain the dead-zone compensation signal and compensation electrical angle for dead-zone compensation.

2. The dead-zone voltage compensation method according to claim 1, characterized in that, The process of obtaining the current components in the five rotating reference frames includes: The real-time three-phase input current of the permanent magnet synchronous motor is sequentially subjected to Clark transformation and Park transformation to obtain the current components in the dq synchronous reference frame. Based on the current components in the dq synchronous reference frame, the current components in the five-fold rotating reference frame are obtained through multiple synchronous rotating coordinate transformations.

3. The dead-zone voltage compensation method according to claim 2, characterized in that, The multi-synchronous rotation coordinate transformation process is implemented using the following transformation matrix: in, This represents the multiple synchronous rotation coordinate transformation matrix. Indicates synchronous speed. t Indicates time.

4. The dead-zone voltage compensation method according to claim 1, characterized in that, The preset dead-time compensation strategy is represented by the following expression: in, This represents the amplitude of the equivalent dead time. This indicates the phase used for adjusting dead-zone compensation injection. , , This indicates the three-phase dead-time compensation signal added to the existing three-phase duty cycle. Indicates the compensation electric angle. Indicates the real-time electrical angle. This indicates that the current leads in the dq synchronous reference frame. q The angle of the axis.

5. The dead-zone voltage compensation method according to claim 1 or 4, characterized in that, The amplitude of the equivalent dead time and the phase used for dead time compensation injection are calculated using the following expressions: in, , These represent the proportional coefficients of the first and second PI controllers, respectively. , These represent the integral coefficients of the first and second PI controllers, respectively. , These respectively represent the fifth harmonic current components. This represents the amplitude of the equivalent dead time. This indicates the phase used for adjusting dead zone compensation injection.

6. A computer-readable storage medium, characterized in that, It includes a series of instructions for performing the method steps as described in any one of claims 1 to 5.

7. A dead-zone voltage compensation system for a permanent magnet synchronous motor, characterized in that, include: The rotating reference frame current component generation module is configured to obtain the three-phase input current of the permanent magnet synchronous motor in real time, and based on this, obtain the current components under the fifth rotating reference frame. The rotating reference frame harmonic current component generation module is configured to perform low-pass filtering on the current component under the fifth rotating reference frame to obtain the fifth harmonic current component. The compensation signal generation module is configured to obtain the injection amplitude and phase for dead-zone voltage compensation based on the cross-coupling processing result of the fifth harmonic current components and the real-time electrical angle of the permanent magnet synchronous motor, and to compensate the inverter drive signal in the original controller of the PMSM. This includes: performing addition and subtraction processing on the fifth harmonic current components respectively, then adjusting the addition result using a first PI control controller to obtain the amplitude of the equivalent dead time, and adjusting the subtraction result using a second PI control controller to obtain the phase for adjusting the dead-zone compensation injection. Then, based on the amplitude of the equivalent dead time, the phase for adjusting the dead-zone compensation injection, and the real-time electrical angle, a preset dead-zone compensation strategy is used to obtain the dead-zone compensation signal and compensation electrical angle for dead-zone compensation.

8. The dead-zone voltage compensation system according to claim 7, characterized in that, The rotating reference frame current component generation module includes: The synchronous reference frame current component generation unit is configured to sequentially pass the real-time three-phase input current of the permanent magnet synchronous motor through Clark transformation and Park transformation to obtain the current component under the dq synchronous reference frame. The multi-synchronous rotation processing unit is configured to obtain the current components in the five-times rotating reference system by performing multi-synchronous rotation coordinate transformation based on the current components in the dq synchronous reference system.

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