A permanent magnet synchronous motor speed control method based on iterative terminal sliding mode algorithm

Abstract

The present invention relates to a permanent magnet synchronous motor speed regulation control method based on an iterative terminal sliding mode algorithm, comprising: establishing a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system, the mathematical model being a calculation formula of the stator current and the derivative of the rotor angular velocity; constructing a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity; designing a traditional non-singular terminal sliding mode surface based on the speed tracking error and the derivative of the speed tracking error in the state equation, and replacing a traditional function in the traditional non-singular terminal sliding mode surface with a non-smooth function to obtain an improved non-singular terminal sliding mode surface; constructing a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface, which enables the speed tracking error of the permanent magnet synchronous motor system to converge to an origin on the non-singular terminal sliding mode surface; and controlling the permanent magnet synchronous motor based on the non-singular terminal sliding mode controller; thereby solving the problem of torque pulsation during operation of the permanent magnet synchronous motor.

Description

Technical Field

[0001] The present invention relates to the field of permanent magnet synchronous motor control, and in particular to a permanent magnet synchronous motor speed regulation control method based on an iterative terminal sliding mode algorithm. Background Art

[0002] Permanent magnet synchronous motors (PMSMs), due to their high power density, high torque density, and wide speed range, have become core power units in aerospace, rail transit, new energy vehicles, and other fields. Therefore, achieving efficient control of PSMs has become a research hotspot. Among PSM control strategies, vector control is widely used in PSM systems due to its high efficiency and accuracy. Its structure consists of a speed loop and two current loops in series. Traditional PI control techniques are widely used in the control design of the speed and current loops due to their simplicity. However, in practical PSM systems, nonlinear internal and external disturbances and uncertainties exist, typically including unmodeled dynamics, parameter perturbations, load disturbances, and torque ripple. In these situations, traditional linear control methods, such as PI control, struggle to achieve satisfactory robustness in PSM systems. To improve the robustness of motor systems, various nonlinear methods have been developed and applied to motors.

[0003] Among various nonlinear control strategies, sliding mode control has attracted widespread attention due to its insensitivity to model errors, parameter perturbations, and external disturbances, and has been successfully applied to permanent magnet synchronous motor speed control systems. Although sliding mode control significantly improves the robustness of permanent magnet synchronous motor systems compared to PI control, there are still challenges to be addressed. For example, traditional linear sliding mode control can only drive the system state to converge asymptotically to the origin and cannot suppress the torque ripples that exist in permanent magnet synchronous motor systems during operation. Summary of the Invention

[0004] In response to the technical problems existing in the prior art, the present invention provides a permanent magnet synchronous motor speed control method and system based on an iterative terminal sliding mode algorithm, further improves the mathematical model of the permanent magnet synchronous motor, and solves the problem of torque pulsation during operation of the permanent magnet synchronous motor.

[0005] According to a first aspect of the present invention, a permanent magnet synchronous motor speed control method based on an iterative terminal sliding mode algorithm is provided, comprising:

[0006] Step 1: Establish a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system, wherein the mathematical model is a calculation formula of the derivative of the stator current and the rotor angular velocity;

[0007] Step 2: constructing a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity;

[0008] Step 3: designing a traditional non-singular terminal sliding surface based on the speed tracking error and the derivative of the speed tracking error in the state equation, and replacing the traditional function in the traditional non-singular terminal sliding surface with a non-smooth function to obtain an improved non-singular terminal sliding surface;

[0009] Step 4: construct a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface, wherein the non-singular terminal sliding mode controller enables the speed tracking error of the permanent magnet synchronous motor system to converge to the origin on the non-singular terminal sliding mode surface; and control the permanent magnet synchronous motor based on the non-singular terminal sliding mode controller.

[0010] On the basis of the above technical solution, the present invention can also make the following improvements.

[0011] Optionally, in step 1, the mathematical model is constructed according to the coordinate transformation principle as follows:

[0012] ;

[0013] in, and are the stator current, voltage and inductance respectively. The axis's weight; is the angular velocity of the rotor; and They are and The derivative of is the load torque; is the number of motor pole pairs; is the phase resistance; is the moment of inertia; is the friction coefficient; is the motor flux.

[0014] Optionally, in step 1, the mathematical model is constructed according to the coordinate transformation principle as follows:

[0015] ;

[0016] in, is the torque ripple; and are the stator current, voltage and inductance respectively. The axis's weight; is the angular velocity of the rotor; and They are and The derivative of is the load torque; is the number of motor pole pairs; is the phase resistance; is the moment of inertia; is the friction coefficient; is the motor flux.

[0017] Optionally, the torque pulsation The calculation formula is: ;in, is the harmonic order; is the electrical angle of the permanent magnet synchronous motor; and are the amplitude and phase angle of the harmonic components.

[0018] Optionally, the state equation in step 2 is:

[0019] ;

[0020] Where, is the desired angular velocity of the rotor, is the angular velocity of the rotor, for The derivative of is the speed tracking error; is the derivative of the speed tracking error.

[0021] Optionally, the improved non-singular terminal sliding surface obtained in step 3 is , is the speed tracking error; is the derivative of the speed tracking error; and is a positive constant, Operator The operation rules are , sign is a function used to determine the positive or negative sign of a number.

[0022] Optionally, the non-singular terminal sliding mode controller constructed in step 4 for:

[0023] ; ;

[0024] in, To control the gain, The stator current is The axis's weight; is the number of motor pole pairs; is the moment of inertia; is the motor flux.

[0025] Optionally, step 4 further includes: constructing an iterative learning law for estimating periodic torque pulsation, and compensating the iterative learning law into the non-singular terminal sliding mode controller as a feedforward signal.

[0026] Optionally, the iterative terminal sliding mode controller constructed in step 4 for:

[0027] ; ;

[0028] in, ;

[0029] Where, To control the gain; It is the iterative learning law; Indicates the number of iterations; 、 and is a positive constant; For the Sliding mode variables of the iteration; is the number of motor pole pairs; is the moment of inertia; is the motor flux.

[0030] According to a second aspect of the present invention, there is provided a permanent magnet synchronous motor speed control system based on an iterative terminal sliding mode algorithm, comprising: a model building module, a state equation building module, a non-singular terminal sliding mode surface building module and a non-singular terminal sliding mode controller building module;

[0031] The model building module is used to establish a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system, wherein the mathematical model is a calculation formula of the derivative of the stator current and the rotor angular velocity;

[0032] The state equation building module is used to build a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity;

[0033] The non-singular terminal sliding surface construction module is used to design a traditional non-singular terminal sliding surface based on the speed tracking error and the derivative of the speed tracking error in the state equation, and to obtain an improved non-singular terminal sliding surface by replacing the traditional function in the traditional non-singular terminal sliding surface with a non-smooth function;

[0034] The non-singular terminal sliding mode controller construction module is used to construct a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface, so that the speed tracking error of the permanent magnet synchronous motor system converges to the origin on the non-singular terminal sliding mode surface, and control the permanent magnet synchronous motor based on the non-singular terminal sliding mode controller.

[0035] The present invention provides a permanent magnet synchronous motor speed control method and system based on an iterative terminal sliding mode algorithm. A non-singular terminal sliding mode controller is constructed, so that the speed tracking error converges to the origin in a finite time, avoiding the singularity problem. An iterative learning law is designed as feedforward compensation for the controller to suppress torque pulsation. The use of the iterative terminal sliding mode controller can improve the anti-interference performance of the permanent magnet synchronous motor speed control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A flow chart of a permanent magnet synchronous motor speed control method based on an iterative terminal sliding mode algorithm provided by the present invention;

[0037] Figure 2 A principle block diagram of a permanent magnet synchronous motor speed control method based on an iterative terminal sliding mode algorithm provided by the present invention;

[0038] Figure 3 This is a schematic diagram comparing the motor speed response curves under the non-singular terminal sliding mode algorithm and the iterative terminal sliding mode algorithm provided by the present invention. DETAILED DESCRIPTION

[0039] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0040] Figure 1 The present invention provides a flow chart of a permanent magnet synchronous motor speed control method based on an iterative terminal sliding mode algorithm, such as Figure 1 As shown, the method includes:

[0041] Step 1: Establish a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system. The mathematical model is a calculation formula for the derivative of the stator current and the rotor angular velocity.

[0042] Step 2: Construct a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity.

[0043] Step 3: Design a traditional non-singular terminal sliding surface based on the speed tracking error and the derivative of the speed tracking error in the state equation, and replace the traditional function in the traditional non-singular terminal sliding surface with a non-smooth function to obtain an improved non-singular terminal sliding surface.

[0044] The traditional non-singular terminal sliding surface is a sliding surface structure designed to solve the singularity problem in traditional terminal sliding mode control. Its core feature is to avoid singular phenomena (such as the denominator being zero) in the control law by adjusting the sliding surface structure parameters.

[0045] Step 4: construct a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface. The non-singular terminal sliding mode controller enables the speed tracking error of the permanent magnet synchronous motor system to converge to the origin on the non-singular terminal sliding mode surface; and control the permanent magnet synchronous motor based on the non-singular terminal sliding mode controller.

[0046] The present invention provides a permanent magnet synchronous motor speed regulation control method based on an iterative terminal sliding mode algorithm, which further improves the mathematical model of the permanent magnet synchronous motor and solves the problem of torque pulsation during operation of the permanent magnet synchronous motor.

[0047] Example 1

[0048] The embodiment 1 provided by the present invention is an embodiment of a permanent magnet synchronous motor speed control method based on an iterative terminal sliding mode algorithm provided by the present invention, such as Figure 2 The figure shows a principle block diagram of a permanent magnet synchronous motor speed control method based on an iterative terminal sliding mode algorithm provided by the present invention, combined with Figure 1 and Figure 2 It can be seen that the embodiment of the speed control method includes:

[0049] Step 1: Establish a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system. The mathematical model is a calculation formula for the derivative of the stator current and the rotor angular velocity.

[0050] In a possible embodiment, in step 1, according to the coordinate transformation principle, it is assumed that the motor system is in an ideal state and the The vector control scheme is constructed as follows:

[0051] .

[0052] in, and are the stator current, voltage and inductance respectively. The axis's weight; is the angular velocity of the rotor; and They are and The derivative of is the load torque; is the number of motor pole pairs; is the phase resistance; is the moment of inertia; is the friction coefficient; is the motor flux.

[0053] In a possible embodiment, the torque equation of the mathematical model is:

[0054] .

[0055] Where, is the electromagnetic torque; and are the stator current and inductance respectively. The axis's components.

[0056] Taking into account the torque pulsation phenomenon of the permanent magnet synchronous motor during operation, the mathematical model of the permanent magnet synchronous motor is further improved, and the torque equation can be further rewritten as:

[0057]

[0058] Where, is the harmonic order; and is the amplitude of the rotor permanent magnet flux and the sixth-order harmonic; is the electrical angle of the permanent magnet synchronous motor; and are the current measurement errors caused by current bias and current scaling, respectively; is the cogging torque. Generally speaking, torque ripple is generated by flux harmonics, cogging torque, and current measurement errors, and the torque ripple varies periodically during motor operation.

[0059] Therefore, the torque equation can be simplified to:

[0060]

[0061] Where, is the torque ripple; and are the amplitude and phase angle of the harmonic components.

[0062] During specific implementation, when the permanent magnet synchronous motor runs at high speed, the torque pulsation will be naturally filtered out to a certain extent by the rotor or load inertia, so the torque pulsation is more obvious when running at low speed.

[0063] Furthermore, the mathematical model of the surface-mounted permanent magnet synchronous motor can be further rewritten as:

[0064] .

[0065] Step 2: Construct a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity; define the motor speed tracking error as a system state variable.

[0066] In a possible embodiment, the state equation in step 2 can be constructed as:

[0067] .

[0068] Where, is the desired angular velocity of the rotor; is the speed tracking error; is the derivative of the speed tracking error.

[0069] For state variables and Further derivation yields:

[0070]

[0071] Where, ; is the control input signal; is the lumped disturbance of the permanent magnet synchronous motor system, satisfying and is a bounded positive constant; is the motor torque ripple to be learned.

[0072] Step 3: Design a traditional non-singular terminal sliding surface based on the speed tracking error and the derivative of the speed tracking error in the state equation, and replace the traditional function in the traditional non-singular terminal sliding surface with a non-smooth function to obtain an improved non-singular terminal sliding surface.

[0073] In a possible embodiment, the improved non-singular terminal sliding mode surface obtained in step 3 is ; and is a positive constant, Operator The operation rules are , sign is a function used to determine the positive or negative sign of a number.

[0074] In the specific implementation, the traditional non-singular terminal sliding surface designed .

[0075] Where, and is a positive odd number and satisfies ;because , the system state will not have singular problems in sliding mode motion.

[0076] In order to make the motor control system faster and with higher tracking accuracy, the traditional non-singular terminal sliding surface Traditional functions in Replace with a non-smooth function .

[0077] It can be seen that compared with the traditional non-singular terminal sliding surface , improved non-singular terminal sliding surface State variables Index The selection is more relaxed.

[0078] Step 4: Construct a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface. The non-singular terminal sliding mode controller enables the speed tracking error of the permanent magnet synchronous motor system to converge to the origin on the non-singular terminal sliding mode surface. Control the permanent magnet synchronous motor based on the non-singular terminal sliding mode controller so that the actual speed of the motor can be quickly and stably tracked to the given speed.

[0079] In a possible embodiment, in order to achieve the control goal, a non-singular terminal sliding mode controller is designed. First, the improved non-singular terminal sliding mode surface Taking the derivative we get:

[0080] .

[0081] According to the equivalent control theory, the state equation of the speed tracking error and the non-singular terminal sliding surface are combined ,make , design an equivalent controller for:

[0082] .

[0083] Ideally, equivalent control can keep the system moving on the sliding surface. However, equivalent control may not be able to move the system state from the arrival phase to the sliding phase, so an additional action called switching control is required, which should be applied to the system together with the equivalent control. Therefore, a non-singular terminal sliding mode controller can be designed. for:

[0084] .

[0085] Where, To ensure that the controller can stabilize the motor system, the control gain It needs to be greater than the upper bound of the disturbance, that is, it satisfies the condition .

[0086] In one possible embodiment, to further improve the non-singular terminal sliding mode controller The torque pulsation suppression capability can be used to construct an iterative learning law to estimate the periodic torque pulsation. for:

[0087] .

[0088] In the formula , and is a positive constant; Indicates the number of iterations; For the Sliding mode variables of the iteration It should be noted that learning gain The larger the value, the faster the convergence speed of iterative learning, but it will also reduce the error convergence accuracy of iterative learning.

[0089] Applying the iterative learning law as a feedforward signal to compensate the non-singular terminal sliding mode controller In this paper, an iterative terminal sliding mode controller can be constructed for:

[0090] .

[0091] The control gain satisfy , the iterative terminal sliding mode controller finally designed It can make the speed tracking error of the permanent magnet synchronous motor system on the non-singular terminal sliding surface Converges to the origin.

[0092] Example 2

[0093] Example 2 provided by the present invention is an embodiment of a permanent magnet synchronous motor speed control system based on an iterative terminal sliding mode algorithm provided by the present invention. The embodiment of the speed control system includes: a model building module, a state equation building module, a non-singular terminal sliding mode surface building module and a non-singular terminal sliding mode controller building module.

[0094] The model building module is used to establish a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system. The mathematical model is a calculation formula for the derivative of the stator current and the rotor angular velocity.

[0095] The state equation building module is used to build a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity.

[0096] The non-singular terminal sliding surface construction module is used to design a traditional non-singular terminal sliding surface based on the speed tracking error and the derivative of the speed tracking error in the state equation. The improved non-singular terminal sliding surface is obtained by replacing the traditional function in the traditional non-singular terminal sliding surface with a non-smooth function.

[0097] A non-singular terminal sliding mode controller building module is used to construct a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface, so that the speed tracking error of the permanent magnet synchronous motor system converges to the origin on the non-singular terminal sliding mode surface, and the permanent magnet synchronous motor is controlled based on the non-singular terminal sliding mode controller.

[0098] It can be understood that the permanent magnet synchronous motor speed control system based on the iterative terminal sliding mode algorithm provided by the present invention corresponds to the permanent magnet synchronous motor speed control method based on the iterative terminal sliding mode algorithm provided in the aforementioned embodiments. The relevant technical features of the permanent magnet synchronous motor speed control system based on the iterative terminal sliding mode algorithm can refer to the relevant technical features of the permanent magnet synchronous motor speed control method based on the iterative terminal sliding mode algorithm, which will not be repeated here.

[0099] like Figure 3 The figure shows a comparison of the motor speed response curves under the non-singular terminal sliding mode algorithm and the iterative terminal sliding mode algorithm provided by the present invention. Figure 3 It can be seen that the permanent magnet synchronous motor speed control method and system based on the iterative terminal sliding mode algorithm provided by the present invention is equivalent to a non-singular terminal sliding mode algorithm. The speed tracking error can converge to the origin faster, avoiding the singularity problem.

[0100] An embodiment of the present invention provides a permanent magnet synchronous motor speed control method and system based on an iterative terminal sliding mode algorithm, constructing a non-singular terminal sliding mode controller so that the speed tracking error converges to the origin in a finite time, avoiding the singularity problem; designing an iterative learning law as the feedforward compensation of the controller to suppress torque pulsation; using the iterative terminal sliding mode controller can improve the anti-interference performance of the permanent magnet synchronous motor speed control system.

[0101] It should be noted that, in the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0102] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0103] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0104] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0105] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0106] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0107] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A permanent magnet synchronous motor speed control method based on an iterative terminal sliding mode algorithm, characterized in that: The speed control method comprises: Step 1: Establish a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system, wherein the mathematical model is a calculation formula of the derivative of the stator current and the rotor angular velocity; Step 2: constructing a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity; Step 3: designing a traditional non-singular terminal sliding surface based on the speed tracking error and the derivative of the speed tracking error in the state equation, and replacing the traditional function in the traditional non-singular terminal sliding surface with a non-smooth function to obtain an improved non-singular terminal sliding surface; Step 4: constructing a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface, wherein the non-singular terminal sliding mode controller causes the speed tracking error of the permanent magnet synchronous motor system to converge to the origin on the non-singular terminal sliding mode surface; and controlling the permanent magnet synchronous motor based on the non-singular terminal sliding mode controller; The improved non-singular terminal sliding surface is obtained in step 3 , is the speed tracking error; is the derivative of the speed tracking error; and is a positive constant, Operator The operation rules are , sign is a function used to determine the positive or negative sign of a number; The non-singular terminal sliding mode controller constructed in step 4 for: ； ； in, To control the gain, The stator current is The axis's weight; is the number of motor pole pairs; is the moment of inertia; is the motor flux; The iterative terminal sliding mode controller constructed in step 4 for: ； ； in, ; Where, To control the gain; It is the iterative learning law; Indicates the number of iterations; 、 and is a positive constant; For the Sliding mode variables of the iteration; is the number of motor pole pairs; is the moment of inertia; is the motor flux.

2. The speed control method according to claim 1, characterized in that: In step 1, the mathematical model is constructed according to the coordinate transformation principle as follows: ； in, and are the stator current, voltage and inductance respectively. The axis's weight; is the angular velocity of the rotor; and They are and The derivative of is the load torque; is the number of motor pole pairs; is the phase resistance; is the moment of inertia; is the friction coefficient; is the motor flux.

3. The speed control method according to claim 1, wherein: In step 1, the mathematical model is constructed according to the coordinate transformation principle as follows: ； in, is the torque ripple; and are the stator current, voltage and inductance respectively. The axis's weight; is the angular velocity of the rotor; and They are and The derivative of is the load torque; is the number of motor pole pairs; is the phase resistance; is the moment of inertia; is the friction coefficient; is the motor flux.

4. The speed control method according to claim 3, characterized in that: The torque ripple The calculation formula is: ;in, is the harmonic order; is the electrical angle of the permanent magnet synchronous motor; and are the amplitude and phase angle of the harmonic components.

5. The speed control method according to claim 1, characterized in that: The state equation in step 2 is: ； Where, is the desired angular velocity of the rotor, is the angular velocity of the rotor, for The derivative of is the speed tracking error; is the derivative of the speed tracking error.

6. The speed control method according to claim 1, characterized in that: The step 4 further includes: constructing an iterative learning law for estimating periodic torque pulsation, and compensating the iterative learning law into the non-singular terminal sliding mode controller as a feedforward signal.

7. A permanent magnet synchronous motor speed control system based on iterative terminal sliding mode algorithm, characterized in that: The speed control system is based on the speed control method according to any one of claims 1 to 6, comprising: a model building module, a state equation building module, a non-singular terminal sliding mode surface building module and a non-singular terminal sliding mode controller building module; The model building module is used to establish a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system, wherein the mathematical model is a calculation formula of the derivative of the stator current and the rotor angular velocity; The state equation building module is used to build a state equation of the motor speed tracking error based on the rotor angular velocity and the desired rotor angular velocity; The non-singular terminal sliding surface construction module is used to design a traditional non-singular terminal sliding surface based on the speed tracking error and the derivative of the speed tracking error in the state equation, and to obtain an improved non-singular terminal sliding surface by replacing the traditional function in the traditional non-singular terminal sliding surface with a non-smooth function; The non-singular terminal sliding mode controller construction module is used to construct a non-singular terminal sliding mode controller based on the state equation and the improved non-singular terminal sliding mode surface, so that the speed tracking error of the permanent magnet synchronous motor system converges to the origin on the non-singular terminal sliding mode surface, and control the permanent magnet synchronous motor based on the non-singular terminal sliding mode controller.

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