Model-free quasi-resonance sliding mode control method and system for permanent magnet synchronous motor

Abstract

The invention discloses a permanent magnet synchronous motor model-free quasi-resonance sliding mode control method and system. The method comprises the following steps: S1, establishing a model-free quasi-resonant sliding mode current controller which is configured with an input and output hyper-local model based on motor control and is a function of a primary time derivative of an output variable relative to a control variable and unknown disturbance; setting an integral sliding mode surface with a quasi-resonance term, and obtaining a control law of the control variable in combination with the hyper-local model; s2, setting an extended state observer which is connected with the model-free quasi-resonance sliding mode current controller and is used for observing the unknown disturbance controlled by the motor and applying the unknown disturbance to a control law of the control variable; and S3, obtaining an observation value of an output variable, and obtaining a value of a control variable applied to motor control according to the control law of the control variable. The model-free quasi-resonance sliding mode control system comprises the model-free quasi-resonance sliding mode current controller and an expansion state observer. The speed fluctuation is reduced, and the torque output quality is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of permanent magnet synchronous motors, and in particular, relates to a model-free quasi-resonant sliding mode control method and system for a permanent magnet synchronous motor. Background Art

[0002] Permanent magnet synchronous motor (PMSM) achieves speed regulation through variable voltage and frequency conversion technology. It has the characteristics of small size, low loss, high efficiency and wide speed regulation range. It has been widely used in recent decades. With the continuous increase in the application fields of permanent magnet synchronous motors, the performance requirements are getting higher and higher. While the design of its main structure is continuously optimized and innovated, the control technology has also developed rapidly.

[0003] In order to achieve excellent control performance in modern applications, the PMSM control system should have the characteristics of fast response, small overshoot, high tracking accuracy, and strong anti-interference ability. Commonly used linear control algorithms, such as proportional integral, are usually used for PMSM speed control due to their simple design and implementation. However, the PMSM drive system is nonlinear and multivariable, with various internal disturbances (parameter changes and unmodeled dynamics) and external disturbances (load torque changes and friction torque, etc.). Although the system disturbances can be suppressed by closed-loop control, these disturbances will inevitably cause PMSM speed response fluctuations, thereby affecting the static and dynamic performance of the motor.

[0004] The above information disclosed in the background technology is only used to increase the understanding of the background technology of the present application, and therefore, it may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] In view of the problem that various internal and external disturbances of permanent magnet synchronous motors cause speed response fluctuations and affect the torque output quality in traditional linear control systems in the prior art, the present invention proposes a model-free quasi-resonant sliding mode control method and system for permanent magnet synchronous motors to reduce speed response fluctuations and improve torque output quality.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] A model-free quasi-resonant sliding mode control method for a permanent magnet synchronous motor comprises the following steps:

[0008] S1. Establish a model-free quasi-resonant sliding mode current controller, which is configured with a hyperlocal model of input and output based on motor control, which is a function of the first time derivative of the output variable relative to the control variable and the unknown disturbance; set an integral sliding mode surface with a quasi-resonant term, and obtain the control law of the control variable in combination with the hyperlocal model;

[0009] S2, setting an extended state observer, which is connected to the model-free quasi-resonant sliding mode current controller, observing the unknown disturbance of the motor control, and applying it to the control law of the control variable;

[0010] S3. Obtain an observed value of the output variable, and obtain a value of the control variable applied to motor control according to the control law of the control variable.

[0011] In some specific embodiments, in step S1, the output variables of the hyperlocal model include the stator current of the d-axis and the stator current of the q-axis, and the control variables include the d-axis voltage and the q-axis voltage; the unknown disturbance is a lumped disturbance including the influence of motor parameters, the uncertainty of the hyperlocal model and external disturbances.

[0012] In some specific embodiments, in step S1, the hyperlocal model is designed according to the basic model in the dq coordinate system and the model-free principle as follows:

[0013]

[0014] In the formula,

[0015] i d 、i q They are d-axis stator current and q-axis stator current respectively;

[0016] α d , α q They are d-axis voltage gain and q-axis voltage gain respectively;

[0017] u d 、u q are d-axis voltage and q-axis voltage respectively;

[0018] F d 、F q They are the lumped disturbances of the d-axis stator current control and the lumped disturbances of the q-axis stator current control respectively.

[0019] In some specific embodiments, in step S1, the combination of the integral sliding surface and the hyperlocal model is realized by a state variable equation;

[0020] The control law of the control variable obtained by combining the integral sliding surface with the hyperlocal model includes:

[0021] First, set the state variable equation

[0022]

[0023] In the formula,

[0024] e q 、e dare the state variables of the q-axis and the d-axis respectively;

[0025] are the expected currents of the q-axis and d-axis to be designed respectively;

[0026] i q 、i d are the stator currents of the q-axis and d-axis respectively;

[0027] Secondly, the state variable equation is differentiated to obtain,

[0028]

[0029] Then, are replaced by The equation for the derivative of the state variable is obtained,

[0030]

[0031] In some specific embodiments, in step S1, the integral sliding surface is,

[0032]

[0033] In the formula,

[0034] e is the state variable; c>0; is the quasi-resonant term, R is the complex frequency domain; ω c is the cut-off frequency; ω is the fundamental frequency;

[0035] The control law of the control variable obtained by combining the integral sliding surface with the super local model also includes:

[0036] By calculating the time derivative of the sliding surface of the q-axis and d-axis respectively, we can get:

[0037] and

[0038]

[0039] Combining the equation of the derivative of the state variable, we get the equation of the derivative of the sliding surface,

[0040]

[0041] In some specific embodiments, the control law of the control variable obtained by combining the integral sliding surface with the hyperlocal model further includes:

[0042] Selection approach law Applying this to the equation for the derivative of the sliding surface yields,

[0043]

[0044] Then the control law of the control variable is obtained:

[0045]

[0046] In some specific embodiments, in step S1, a PI control module is provided in the model-free quasi-resonant sliding mode current controller;

[0047] Get the real-time angular velocity; the expected current of the q axis It is obtained by the PI control module according to the reference angular velocity and the real-time angular velocity; the reference angular velocity is obtained by setting.

[0048] In some specific embodiments, in step S2, the extended state observer is configured to observe the output variable to obtain an output variable observation value, and obtain an estimated value of the unknown disturbance based on the output variable observation value to replace the unknown disturbance in the control law of the control variable.

[0049] In some specific embodiments, the extended state observer is configured to control the q-axis and d-axis current loops as follows:

[0050]

[0051] In the formula,

[0052] i′ q , i′ d are the observed values ​​of the q-axis and d-axis stator currents respectively;

[0053] F q ′、F d ′ are the estimated values ​​of the unknown disturbances on the q-axis and d-axis respectively;

[0054] θ is the nonlinear factor;

[0055] δ is the filtering factor;

[0056] ε q , ε d are the observation errors of the q-axis and d-axis stator currents respectively;

[0057]

[0058] A model-free quasi-resonant sliding mode control system for a permanent magnet synchronous motor, used to execute the above-mentioned model-free sliding mode control method for a permanent magnet synchronous motor, comprising:

[0059] A model-free quasi-resonant sliding mode current controller, used to obtain a control variable output according to a control law of a desired output variable and a control variable, and to supply power to the permanent magnet synchronous motor;

[0060] An extended state observer is connected to the model-free quasi-resonant sliding mode current controller and is used to observe unknown disturbances and transmit the disturbances to the model-free quasi-resonant sliding mode current controller.

[0061] Compared with the prior art, the advantages and positive effects of the present invention are:

[0062] The model-free quasi-resonant sliding mode control method and system of the permanent magnet synchronous motor of the present invention are provided with a model-free quasi-resonant sliding mode current controller and an extended state observer, and a hyperlocal model based on the output variables and control variables of the PMSM system is configured in the model-free quasi-resonant sliding mode current controller, so that the influence of motor parameters and unknown interference are regarded as unknown disturbances of the system, thereby preventing the influence of parameter drift on control performance and reducing the dependence on the motor model and motor parameters; by introducing a quasi-resonant term in the sliding mode surface, the torque pulsation caused by current harmonics is effectively suppressed, the quality of torque output is improved, and the problem that although the model-free control can eliminate the influence of the unmodeled dynamics of the system to a certain extent, it is affected by the estimation accuracy of the unknown disturbance of the hyperlocal model of the system; in addition, for the unknown disturbance in the hyperlocal model, the estimation and feed-forward compensation are performed by the extended state observer, so as to improve the estimation accuracy of the unknown disturbance, reduce the influence of the estimated value of the unknown disturbance, and further improve the control accuracy of the system.

[0063] After reading the specific embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0065] Figure 1 It is an overall structural block diagram of an embodiment of a model-free quasi-resonant sliding mode control system of a permanent magnet synchronous motor proposed by the present invention;

[0066] Figure 2 It is an overall structural block diagram of another embodiment of a model-free quasi-resonant sliding mode control system of a permanent magnet synchronous motor proposed by the present invention;

[0067] Figure 3 It is a simulation diagram of the speed change of a permanent magnet synchronous motor and a PI-controlled permanent magnet synchronous motor subjected to a disturbance using a model-free quasi-resonant sliding mode control method or system;

[0068] Figure 4aThis is the simulation diagram of the a-phase current of the permanent magnet synchronous motor with PI control applied disturbance;

[0069] Figure 4b It is a simulation diagram of the a-phase current of a permanent magnet synchronous motor subjected to disturbance by using a model-free quasi-resonant sliding mode control method or system;

[0070] Figure 5a This is a simulation diagram of the fundamental wave content of the disturbance applied to the permanent magnet synchronous motor controlled by PI;

[0071] Figure 5b It is a simulation diagram of the fundamental wave content of the disturbance applied to the permanent magnet synchronous motor using the model-free quasi-resonant sliding mode control method or system;

[0072] Figure 6 It is a simulation diagram of torque change when disturbance is applied to a permanent magnet synchronous motor and a permanent magnet synchronous motor controlled by PI using a model-free quasi-resonant sliding mode control method or system. DETAILED DESCRIPTION

[0073] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0074] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore, should not be understood as a limitation on the present invention.

[0075] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In the description of the implementation method, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0076] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0077] In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0078] Reference Figure 1 A model-free sliding mode control method for a permanent magnet synchronous motor of the present invention comprises:

[0079] S1. Setting a model-free quasi-resonant sliding mode current controller, wherein the configuration is based on a hyperlocal model of the input and output of the motor control; the hyperlocal model is specifically a function of the first time derivative of the output variable relative to the control variable and the unknown disturbance; setting an integral sliding mode surface with a quasi-resonant term, and obtaining the control law of the control variable in combination with the hyperlocal model;

[0080] The output variable of the permanent magnet synchronous motor is voltage, the control variable is current, and the unknown disturbance is the interference term including the influence of motor parameters and unknown interference; the hyperlocal model based on input and output only involves the output variable of stator current and the control variable of voltage, and does not involve any motor parameters; the motor parameters refer to but are not limited to the mechanical parameters and electrical parameters of the motor;

[0081] S2, setting an extended state observer, which is connected to the model-free quasi-resonant sliding mode current controller, observing the unknown disturbance of the motor control and transmitting it to the model-free quasi-resonant sliding mode current controller; the model-free quasi-resonant sliding mode current controller receives the observed unknown disturbance and applies it to the control law of the control variable; that is, the lumped disturbance in the PMSM system affected by the motor parameters, the uncertainty of the super-local model and the external unknown disturbance is estimated, applied to the control law of the control variable, and the control variable is compensated;

[0082] S3. The model-free quasi-resonant sliding mode current controller obtains the observed value of the output variable, and the value of the control variable applied to the motor control is obtained by the control law of the control variable.

[0083] The present invention also discloses a model-free sliding mode control system for a permanent magnet synchronous motor, which executes the above-mentioned model-free sliding mode control method, including a model-free quasi-resonant sliding mode current controller and an extended state observer connected thereto; the model-free quasi-resonant sliding mode current controller is used to obtain a control variable according to a control law of a desired output variable and a control variable, and is used to control the power supply of the permanent magnet synchronous motor. The extended state observer is used to observe unknown disturbances and transmit the observed unknown disturbances to the model-free quasi-resonant sliding mode current controller, which is used to calculate or compensate for the output control variable.

[0084] The permanent magnet synchronous motor model-free sliding mode control method and control system of the present invention configure a hyperlocal model based on the output variables and control variables of the PMSM system in a model-free quasi-resonant sliding mode current controller, and regard the influence of motor parameters and unknown interference as unknown disturbances of the system, thereby preventing the influence of parameter drift on control performance and reducing the dependence on the motor model and motor parameters; by introducing a quasi-resonant term in the sliding mode surface, the torque pulsation caused by current harmonics is effectively suppressed, the quality of torque output is improved, and the problem that although model-free control can eliminate the influence of the unmodeled dynamics of the system to a certain extent, it is affected by the estimation accuracy of the unknown disturbance of the system hyperlocal model is solved; in addition, for the unknown disturbance in the hyperlocal model, the estimation and feed-forward compensation are performed by extending the state observer, the estimation accuracy of the unknown disturbance is improved, the influence of the estimated value of the unknown disturbance is reduced, and the control accuracy of the system is further improved.

[0085] The principles of the model-free quasi-resonant sliding mode control method and system for a permanent magnet synchronous motor of the present invention are described in detail below through specific embodiments.

[0086] In some specific embodiments, the output variables of the hyperlocal model include the stator current of the d-axis and the stator current of the q-axis; the control variables include the d-axis voltage and the q-axis voltage; the unknown disturbance is a lumped disturbance including the influence of motor parameters, the uncertainty of the hyperlocal model and the external unknown disturbance.

[0087] In some specific embodiments, the mathematical model of the permanent magnet synchronous motor in the dq coordinate system is:

[0088] Among them, R s is the stator resistance; L d and L q are the stator inductances of the d-axis and q-axis respectively; u d and u q are the d-axis and q-axis stator voltages respectively; i d and i q are the stator currents of the d-axis and q-axis respectively; n p is the pole pair number; T e is the electromagnetic torque; J is the moment of inertia; ω is the mechanical angular velocity; B is the friction coefficient; Φ is the permanent magnet flux; f d and f q and f ω are disturbances caused by changes in model parameters and external loads. They can be defined as

[0089]

[0090] Among them, ΔR s =R st -R s , ΔLd =L dt -L d , ΔL q =L qt -L q , ΔB=B t -B, ΔΦ=Φ t -Φ, ΔJ = J t -J is the parameter change value. st , L dt , L qt , B t , Φ t , J t is the actual parameter τ during motor operation L is the external load torque.

[0091] According to the mathematical model of permanent magnet synchronous motor in dq coordinate system and model-free control principle, a hyperlocal model based on the input and output of motor control system is designed to replace some nonlinear, complex and variable systems. The first-order hyperlocal model of a single-input and single-output system is expressed as

[0092]

[0093] In the formula, y and u are the output variable and control variable of the system respectively; α is a constant; and F represents the unknown disturbance of the system.

[0094] In order to reduce the dependence of the speed controller and current controller on the permanent magnet synchronous motor system model, the super-local model of the permanent magnet synchronous motor speed loop and current loop is designed according to formula (3):

[0095]

[0096] In the formula,

[0097] i d 、i q They are d-axis stator current and q-axis stator current respectively;

[0098] α d , α q They are d-axis voltage gain and q-axis voltage gain respectively;

[0099] u d 、u q are d-axis voltage and q-axis voltage respectively;

[0100] F d 、F q They are the lumped disturbances of the d-axis stator current control and the lumped disturbances of the q-axis stator current control respectively.

[0101] In some specific embodiments, in step S1, the integration of the integral sliding surface and the hyperlocal model is implemented through a state variable equation; specifically including:

[0102] Establish a state variable equation; wherein the state variable is the difference between the expected output variable and the output variable; in combination with the hyperlocal model, obtain the function of the derivative of the state variable relative to the derivative of the expected output variable, the control variable and the unknown disturbance; that is, respectively calculate the first derivative of time on both sides of the state variable equation, and obtain the equation of the first derivative of the state variable with respect to time relative to the derivative of the expected output variable with respect to time and the derivative of the output variable with respect to time; replace the derivative of the output variable with respect to time after the state variable equation is derived with the equivalent expression of the derivative of the output variable with respect to time in the hyperlocal model, and obtain the function of the first derivative of the state variable with respect to time relative to the derivative of the expected output variable with respect to time, the control variable and the unknown disturbance; that is, obtain the equation of the first derivative of the state variable with respect to time and the derivative of the expected output variable with respect to time, the control variable and the unknown disturbance;

[0103] An integral sliding surface with a quasi-resonant term is set, and a function of the derivative of the integral sliding surface relative to the desired output variable, the control variable, and the unknown disturbance is obtained by combining the function of the derivative of the state variable; that is, the integral sliding surface is a function of the state variable and the quasi-resonant term; the integral sliding surface equation is differentiated to obtain the derivative of the integral sliding surface and the derivative of the state variable, and the equation of the quasi-resonant term; the equivalent expression of the derivative of the state variable is replaced by the derivative of the state variable in the function of the derivative of the integral sliding surface, and the function of the derivative of the integral sliding surface relative to the desired output variable, the control variable, the unknown disturbance, the state variable, and the quasi-resonant term is obtained;

[0104] A reaching law is selected and combined with a function of a derivative of an integral sliding surface to obtain a control law of a control variable; that is, the derivative of the integral sliding surface in a function of a derivative of the integral sliding surface relative to a desired output variable, a control variable, an unknown disturbance, a state variable, and a quasi-resonant term is replaced with an equivalent formula of the reaching law, and the equivalent formula of the control variable is calculated to obtain the control law of the control variable, which is composed of an equivalent formula of the derivative of the desired output variable, an unknown disturbance, a state variable, a quasi-resonant term, and a reaching law.

[0105] In some specific embodiments, the state variable equation is

[0106]

[0107] In the formula,

[0108] e q 、e d are the state variables of the q-axis and d-axis respectively;

[0109] are the expected currents of the q-axis and d-axis to be designed respectively;

[0110] i q 、i d are the stator currents of the q-axis and d-axis respectively;

[0111] By differentiating the state variable equation, we obtain

[0112]

[0113] In the formula, are replaced by The equation for the derivative of the state variable is,

[0114]

[0115] In some specific embodiments, the integrated sliding mode surface with quasi-resonant terms is,

[0116]

[0117] In the formula,

[0118] e is the state variable; c>0; R is the complex frequency domain; ω c is the cut-off frequency; ω is the fundamental frequency;

[0119] By differentiating the sliding surface of the q-axis and d-axis, we can get:

[0120]

[0121]

[0122] Combining the equations of the derivatives of the state variables, we get the equations of the derivatives of the sliding surface,

[0123]

[0124] In some specific embodiments, the convergence law is selected as

[0125]

[0126] The equation for the derivative applied to the sliding surface yields,

[0127]

[0128] Then we get the control law of the control variable,

[0129]

[0130] In some specific embodiments, reference Figure 2 , setting a PI control module in a model-free quasi-resonant sliding mode current controller;

[0131] Get real-time angular velocity; expected current of q axis It is obtained by the PI control module based on the reference angular velocity and the real-time angular velocity; the reference angular velocity is obtained by the setting.

[0132] In some specific embodiments, reference Figure 2 ,The real-time angular velocity is obtained through the encoder set in the permanent magnet synchronous motor.

[0133] In some specific embodiments, in step S2, the extended state observer is configured to observe the output variable to obtain the output variable observation value, and obtain the estimated value of the unknown disturbance based on the output variable observation value to replace the unknown disturbance in the control law of the control variable.

[0134] In some specific embodiments, the control laws of the extended state observer for the q-axis and d-axis current loops are respectively:

[0135]

[0136]

[0137] In the formula,

[0138] i′ q , i′ d are the observed values ​​of the q-axis and d-axis stator currents respectively;

[0139] F′ q , F′ d are the estimated values ​​of the unknown disturbances on the q-axis and d-axis respectively;

[0140] θ is the nonlinear factor;

[0141] δ is the filtering factor;

[0142] ε q , ε d are the observation errors of the q-axis and d-axis stator currents respectively;

[0143]

[0144] In a specific example, refer to Figure 3 , Figure 4a , Figure 4b , Figure 5a , Figure 5b , Figure 6 , the superiority of the model-free quasi-resonant sliding mode control system is verified in MATLAB / Simulink simulation. In order to better verify the speed tracking performance and anti-interference ability of the control system, it is compared with the control system based on PI controller. A 2μs dead time is added to the simulation, and a step load of 10N·m is suddenly applied to the motor at 0.2s.

[0145] Figure 3 The figure shows the speed fluctuation trend of the control system of the PI controller and the model-free quasi-resonant sliding mode control system RSMC after the step load is applied. The speed fluctuation of the model-free quasi-resonant sliding mode control system RSMC is significantly smaller than that of the control system of the PI controller, and has better anti-interference performance.

[0146] Figure 4a , 4b The a-phase current waveforms of the control system of the PI controller and the model-free quasi-resonant sliding mode control system RSMC after the step load is applied are shown respectively; obviously, the a-phase current deformation of the model-free quasi-resonant sliding mode control system RSMC is smaller, smoother and more stable.

[0147] Figure 5a , 5b The percentage of current harmonic content to fundamental current content of the control system of the PI controller and the model-free quasi-resonant sliding mode control system RSMC after the step load is applied is shown respectively; obviously, the total harmonic content of the model-free quasi-resonant sliding mode control system RSMC accounts for a lower percentage of fundamental current, and the anti-harmonic performance is better.

[0148] Figure 6 The torque change waveforms of the control system of the PI controller and the model-free quasi-resonant sliding mode control system RSMC after the step load is applied are shown; the torque output of the model-free quasi-resonant sliding mode control system RSMC is more stable.

[0149] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to replace some of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions claimed to be protected by the present invention.

Claims

1. A model-free quasi-resonant sliding mode control method for a permanent magnet synchronous motor, characterized in that: The following steps are involved: S1. Setting a model-free quasi-resonant sliding mode current controller, which is configured with a hyperlocal model of input and output based on motor control; the hyperlocal model is a function of the first time derivative of the output variable relative to the control variable and the unknown disturbance; setting an integral sliding mode surface with a quasi-resonant term, and obtaining the control law of the control variable in combination with the hyperlocal model; S2, setting an extended state observer, which is connected to the model-free quasi-resonant sliding mode current controller, observing the unknown disturbance of motor control and transmitting it to the model-free quasi-resonant sliding mode current controller, and applying it to the control law of the control variable; S3. The model-free quasi-resonant sliding mode current controller obtains an observed value of an output variable, and obtains a value of a control variable applied to motor control according to a control law of the control variable.

2. The model-free quasi-resonant sliding mode control method according to claim 1, characterized in that: In step S1, the output variables of the hyperlocal model include the stator current of the d-axis and the stator current of the q-axis, and the control variables include the d-axis voltage and the q-axis voltage; the unknown disturbance is a lumped disturbance including the influence of motor parameters, the uncertainty of the hyperlocal model and external disturbances.

3. The model-free quasi-resonant sliding mode control method according to claim 2, characterized in that: In step S1, the hyperlocal model is designed according to the basic model in the dq coordinate system and the model-free principle as follows: In the formula, i d 、i q They are d-axis stator current and q-axis stator current respectively; α d , α q They are d-axis voltage gain and q-axis voltage gain respectively; u d 、u q are d-axis voltage and q-axis voltage respectively; F d 、F q They are the lumped disturbances of the d-axis stator current control and the lumped disturbances of the q-axis stator current control respectively.

4. The model-free quasi-resonant sliding mode control method according to claim 3, characterized in that: In step S1, the integration of the integral sliding surface and the hyperlocal model is realized by a state variable equation; The control law of the control variable obtained by combining the integral sliding surface with the hyperlocal model includes: First, set the state variable equation In the formula, e q 、e d are the state variables of the q-axis and the d-axis respectively; are the expected currents of the q-axis and d-axis to be designed respectively; i q 、i d are the stator currents of the q-axis and d-axis respectively; Secondly, the state variable equation is differentiated to obtain, Then, are replaced by The equation for the derivative of the state variable is obtained, 5. The model-free quasi-resonant sliding mode control method according to claim 4, characterized in that: In step S1, the integral sliding surface is, In the formula, e is the state variable; c>0; is the quasi-resonant term, R is the complex frequency domain; ω c is the cut-off frequency; ω is the fundamental frequency; The control law of the control variable obtained by combining the integral sliding surface with the super local model also includes: By calculating the time derivative of the sliding surface of the q-axis and d-axis respectively, we can get: and Combining the equation of the derivative of the state variable, we get the equation of the derivative of the sliding surface, 6. The model-free quasi-resonant sliding mode control method according to claim 5, characterized in that: The control law of the control variable obtained by combining the integral sliding surface with the super local model also includes: Selection approach law Applying this to the equation for the derivative of the integral sliding surface yields, Then the control law of the control variable is obtained:

7. The model-free quasi-resonant sliding mode control method according to any one of claims 4 to 6, characterized in that: In step S1, a PI control module is set in the model-free quasi-resonant sliding mode current controller; Get the real-time angular velocity; the expected current of the q axis Obtained by the PI control module according to the reference angular velocity and the real-time angular velocity; The reference angular velocity is obtained by setting.

8. The model-free quasi-resonant sliding mode control method according to any one of claims 1 to 6, characterized in that: In step S2, the extended state observer is configured to observe the output variable to obtain an output variable observation value, and obtain an estimated value of the unknown disturbance based on the output variable observation value to replace the unknown disturbance in the control law of the control variable.

9. The model-free quasi-resonant sliding mode control method according to claim 8, characterized in that: The extended state observer is configured such that the control laws for the q-axis and d-axis current loops are respectively In the formula, i ′ q 、i ′ d are the observed values ​​of the q-axis and d-axis stator currents respectively; F q ′ 、F d ′ are the estimated values ​​of the unknown disturbances on the q-axis and d-axis respectively; θ is the nonlinear factor; δ is the filtering factor; ε q , ε d are the observation errors of the q-axis and d-axis stator currents respectively; 10. A model-free quasi-resonant sliding mode control system for a permanent magnet synchronous motor, used to execute the model-free sliding mode control method for a permanent magnet synchronous motor according to claims 1 to 9, characterized in that: include: A model-free quasi-resonant sliding mode current controller, used to obtain a control variable output according to a control law of a desired output variable and a control variable, and to supply power to the permanent magnet synchronous motor; An extended state observer is connected to the model-free quasi-resonant sliding mode current controller and is used to observe unknown disturbances and transmit the disturbances to the model-free quasi-resonant sliding mode current controller.

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