CN106655938A - Permanent magnet synchronous machine control system and permanent magnet synchronous machine control method based on high-order sliding mode method - Google Patents

Abstract

The invention relates to a permanent magnet synchronous motor control system based on a high-order sliding mode method, which is characterized in that it includes a Cark transformation module, a Park transformation module, a rotary transformer, a high-order sliding mode observer, and a second-order superhelical sliding mode control device, first comparator, second comparator, permanent magnet synchronous motor d-axis current loop proportional-integral controller, permanent magnet synchronous motor q-axis current loop proportional-integral controller, Park inverse transformation module, pulse width modulation module and inverter device; the invention can quickly and effectively adjust various input and output parameters of the permanent magnet synchronous motor under the condition of being disturbed, the dynamic response speed is fast, the robustness is high, and the control accuracy and operation efficiency of the permanent magnet synchronous motor are improved. reliability.

Description

Permanent magnet synchronous motor control system and control method based on high-order sliding mode method

technical field

The invention relates to the technical field of permanent magnet synchronous motors, in particular to a permanent magnet synchronous motor control system and control method based on a high-order sliding mode method.

Background technique

In recent years, with the development of rare earth permanent magnet materials and power devices, permanent magnet synchronous motors (Permanent Magnet Synchronous Motor, PMSM) have received extensive attention for their high performance, high torque inertia ratio and high energy density, especially The decline in the price of permanent magnet materials and the improvement of magnetic properties have greatly promoted the development and application of permanent magnet synchronous motors. In recent years, the permanent magnet synchronous motor system is playing an increasingly important role in the servo system with high precision and wide speed range. Permanent magnet synchronous motor is a multivariable, strongly coupled nonlinear system. Its application environment is generally complex and often has various disturbances, and there are uncertainties such as parameter perturbation and load disturbance.

Among the existing motor control technologies, vector control is the most widely used. The permanent magnet synchronous motor vector control adopts a double closed-loop structure of the speed outer loop and the current inner loop. Among them, the current loop often needs to firstly transform the three-phase current through synchronous rotation coordinate transformation (Direct-quadrature axis transformation, dq transformation for short), and then perform PI (Proportional-Integral, PI) adjustment, the result of PI adjustment is used as the modulation input of PWM (Pulse Width Modulation, pulse width modulation), and the control signal is output through the PWM algorithm to complete the control of the motor. The speed loop generally adds some control strategies. In recent years, with the further development of modern control theory, power devices, power electronics technology and other related sciences, many speed regulation strategies for the speed loop of permanent magnet synchronous motors have been proposed, such as predictive control , adaptive control, neural network control, fuzzy control, etc. However, the dynamic response of the traditional vector control motor is slow, and the motor parameters will change with the load during operation, that is, load disturbance, etc., which will affect the control accuracy of the motor.

Contents of the invention

The object of the present invention is to provide a permanent magnet synchronous motor control system and control method based on a high-order sliding mode method, the system and method can quickly and effectively adjust the various inputs and outputs of the permanent magnet synchronous motor in the case of interference parameters, fast dynamic response and high robustness, which improves the control accuracy and operation reliability of the permanent magnet synchronous motor.

In order to solve the above technical problems, the present invention discloses a permanent magnet synchronous motor control system based on a high-order sliding mode method, which is characterized in that it includes a Cark transformation module, a Park transformation module, a resolver, a high-order sliding mode observer, Second-order super-helical sliding mode controller, first comparator, second comparator, permanent magnet synchronous motor d-axis current loop proportional-integral controller, permanent magnet synchronous motor q-axis current loop proportional-integral controller, Park inverse transformation module, Pulse width modulation module and inverter;

Among them, the input terminal of the resolver is connected to the rotor parameter output terminal of the permanent magnet synchronous motor, the rotor position output terminal of the resolver is connected to the rotor position data input terminal of the Park transformation module; the rotor angular velocity data output terminal of the resolver is connected to the high-order sliding mode observation The input end of the rotor angular velocity data of the resolver, the output end of the observed disturbance value of the high-order sliding mode observer is connected to the input end of the observed disturbance value of the second-order superhelix sliding mode controller; the output end of the rotor angular velocity data of the resolver is also connected to the second-order superhelix The rotor angular velocity input terminal of the sliding mode controller; the reference data input terminal of the second-order superhelical sliding mode controller is used to receive the preset given speed of the permanent magnet synchronous motor; the output terminal of the second-order superhelical sliding mode controller is connected to the first The reference data input end of the second comparator, the output end of the second-order super-helical sliding mode controller is also connected to the observation data input end of the high-order sliding mode observer;

The input end of the Cark transformation module is connected to the current output end of the permanent magnet synchronous motor, and the output end of the Cark transformation module is connected to the input end of the Park transformation module;

The d-axis current output terminal of the permanent magnet synchronous motor of the Park transformation module is connected to the feedback input terminal of the first comparator, the input terminal of the first comparator is used to input the d-axis reference current of the permanent magnet synchronous motor, and the output terminal of the first comparator is passed through The permanent magnet synchronous motor d-axis current loop proportional integral controller is connected to the permanent magnet synchronous motor d-axis voltage input terminal of the Park inverse conversion module;

The q-axis current output terminal of the permanent magnet synchronous motor of the Park transformation module is connected to the feedback input terminal of the second comparator, and the output terminal of the second comparator is connected to the permanent magnet synchronous motor q-axis current loop proportional integral controller of the Park inverse transformation module. Magnetic synchronous motor q-axis voltage input terminal;

The output end of the Park inverse transformation module is connected to the input end of the pulse width modulation module, the output end of the pulse width modulation module is connected to the input end of the inverter, and the output end of the inverter is connected to the three-phase voltage input end of the permanent magnet synchronous motor.

A kind of permanent magnet synchronous motor control method utilizing above-mentioned system, it is characterized in that, it comprises the steps:

Step 1: Collect the rotor position θ of the permanent magnet synchronous motor, the rotor mechanical angular velocity ω _m and the three-phase currents _{i a , i b and} i _{c .} Clark transform and Park transform to obtain the equivalent current i _d and i _q of the permanent magnet synchronous motor in the dq-axis coordinate system, (as shown in Figure 1, a motor along the permanent magnet flux vector and its vertical direction defined synchronously rotating coordinate system);

Step 2: The collected permanent magnet synchronous motor rotor mechanical angular velocity ω _m and the preset permanent magnet synchronous motor given speed Bringing in the second-order super-helical sliding mode controller, the output value of the controller is:

Among them, ω _m is the actual rotor mechanical angular velocity, For a given rotor mechanical angular velocity, is the first derivative of ω _m , for The first derivative of , for , c is the sliding mode control design parameter, B is the friction damping coefficient of the permanent magnet synchronous motor, J is the moment of inertia of the permanent magnet synchronous motor, k _p is the proportional integral of the q-axis current loop of the permanent magnet synchronous motor (Proportional-Integral, PI ) controller proportional coefficient, _ki is the integral coefficient of the permanent magnet synchronous motor q-axis current loop proportional-integral controller, λ ₁ , λ ₂ are the superhelical sliding mode parameters related to the system dynamic response capability and the magnitude of the disturbance, σ is the speed according to The sliding mode variable of the error and its derivative design, sgn() is a sign function, u is the controller output value of the second-order superhelical sliding mode controller, τ is the integral time variable;

Step 3: Input the collected rotor mechanical angular velocity ω _m of the permanent magnet synchronous motor and the controller output value u of the second-order superhelical sliding mode controller obtained in step 2 into the high-order sliding mode observer to obtain the disturbance observation value:

in, is the first derivative of the motor speed ω _m , is the observed value of motor speed ω _m , ω _m is the actual rotor mechanical angular velocity, for The first derivative of , for derivative of is the interference observation k ₁ , k ₂ , and k ₃ are positive constants, among which k ₁ determines the convergence speed of the observer, the size of k ₂ is determined by the maximum disturbance of the motor system, and k ₃ is determined by the maximum change rate of the system disturbance, is the rotational speed error, B is the friction damping coefficient of the permanent magnet synchronous motor, k _p is the proportional integral controller proportional coefficient of the q-axis current loop of the permanent magnet synchronous motor, J is the moment of inertia of the permanent magnet synchronous motor, k _i is the q of the permanent magnet synchronous motor Shaft current loop proportional integral controller integral coefficient, the observer can obtain accurate observation values of various physical quantities when it is stable;

Step 4: The observed disturbance value observed in step (3) Bringing into the controller output value formula of the second-order superhelical sliding mode controller in step (2), the final output value U of the controller of the second-order superhelical sliding mode controller is obtained:

Step 5: The final output value U of the controller of the second-order superhelical sliding mode controller is combined with the second-order model of the permanent magnet synchronous motor based on the speed to obtain the q-axis reference current of the permanent magnet synchronous motor for:

Among them, U is the final output value of the controller of the second-order super-helical sliding mode controller, _kp is the proportional-integral controller proportional coefficient of the q-axis current loop of the permanent magnet synchronous motor, and J is the moment of inertia of the permanent magnet synchronous motor (13), k _f = 1.5n _p ψ _f /J is the intermediate variable, _ki is the integral coefficient of the permanent magnet synchronous motor q-axis current loop proportional-integral controller, s is the Laplace operator, n _p is the number of pole pairs of the permanent magnet synchronous motor, ψ _f represents the rotor flux linkage of the permanent magnet synchronous motor;

Step 6: Set the d-axis reference current of the permanent magnet synchronous motor and the q-axis reference current of the permanent magnet synchronous motor After making difference with the equivalent current i _d and i _q of the permanent magnet synchronous motor in the dq axis coordinate system respectively, the proportional integral control is performed to obtain the input voltage u _d and u _q of the permanent magnet synchronous motor in the dq axis coordinate system;

Step 7: Perform Park inverse transformation on the input voltage u _d and u _q of the permanent magnet synchronous motor in the dq axis coordinate system to obtain the input voltage u _α and u _β of the permanent magnet synchronous motor in the αβ axis coordinate system, and u _α and u _β as the carrier signal, the switching tube control signal of the inverter is obtained through sinusoidal pulse width modulation (Sinusoidal Pulse Width Modulation, SPWM), and the switching tube control signal of the inverter is input to the inverter control circuit to control the inverter The insulated gate bipolar transistor in the device is turned on and off, and then the three-phase input voltage of the permanent magnet synchronous motor is output to drive the permanent magnet synchronous motor at a given rotor mechanical angular velocity run.

Compared with the prior art, the above technical solution conceived by the present invention has the following beneficial effects:

(1) The derivation of the second-order model of the permanent magnet synchronous motor and the adoption of the second-order superhelical sliding mode control greatly enhance the anti-interference ability of the permanent magnet synchronous motor control system, and at the same time significantly reduce chattering. When the second-order or higher-order sliding mode control method is used, the discontinuous part of the control variable exists in the high-order differential of the sliding mode variable, and the designed control law will make the sliding mode variable and its differential (higher-order differential) quantities All converge to zero at steady state. The output of the second-order or higher-order sliding mode controller is the result of the integration of discontinuous higher-order differentials or multiple integrations, so it is continuous. Also, because of the integral in the control process, a large control input can be generated quickly when the system is disturbed and a control error occurs, so that the anti-interference ability of the system is greatly enhanced.

(2) Combining high-order sliding mode disturbance observation compensation with second-order superhelical sliding mode control, the second-order sliding mode control method is introduced in the speed loop of the permanent magnet synchronous motor vector control system, and the disturbance is observed based on the high-order sliding mode observation method , at the same time, the disturbance observation value is feed-forward compensated to the second-order sliding mode controller, and a relatively stable q-axis reference current is obtained; according to the vector control theory, the output torque of the permanent magnet synchronous motor is proportional to the q-axis reference current, so that the permanent The output such as the rotational speed of the magnetic synchronous motor can follow or remain at the set value under complex working conditions, and the response speed and stability of other output quantities such as torque and three-phase output current have been significantly improved, and the robustness has been significantly improved improve.

(3) The high-order sliding mode observer of the present invention has the characteristics of an adaptive low-pass filter, which can automatically adjust the bandwidth of the low-pass filter with the change of the motor system, effectively filter out high-frequency chattering, and make each intermediate physical quantity smoother , which effectively solves the chattering problem of sliding mode control and improves the reliability of the permanent magnet synchronous motor system operation.

(4) The present invention not only includes a second-order sliding mode control method of superhelical sliding mode, other second-order sliding mode control methods such as Twisting algorithm, Sub-optimal algorithm, Prescribed Convergence algorithm and Quasi-Continuous Control algorithm, etc. The control design and formula directly brought into the present invention are implemented.

Description of drawings

Fig. 1 is a block diagram of the present invention;

Fig. 2 is a schematic diagram of coordinate transformation;

Fig. 3 is the rotating speed waveform figure of permanent magnet synchronous motor;

Fig. 4 is the output torque figure of permanent magnet synchronous motor;

Figure 5 is a schematic diagram of the reference value of the q-axis current output by the speed loop controller of the permanent magnet synchronous motor.

Among them, 1—Cark transformation module, 2—Park transformation module, 3—resolver, 4—high-order sliding mode observer, 5—second-order superhelical sliding mode controller, 6—first comparator, 7—second Comparator, 8—permanent magnet synchronous motor d-axis current loop proportional integral controller, 9—permanent magnet synchronous motor q axis current loop proportional integral controller, 10—Park inverse transformation module, 11—pulse width modulation module, 12—inverse Transformer, 13—permanent magnet synchronous motor.

detailed description

Below in conjunction with accompanying drawing and specific embodiment the present invention is described in further detail:

A permanent magnet synchronous motor control system based on a high-order sliding mode method of the present invention, which includes a Cark transformation module 1, a Park transformation module 2, a rotary transformer 3, a high-order sliding mode observer 4, and a second-order superhelical sliding mode control 5, first comparator 6, second comparator 7, permanent magnet synchronous motor d-axis current loop proportional-integral controller 8, permanent magnet synchronous motor q-axis current loop proportional-integral controller 9, Park inverse transformation module 10, pulse Width modulation module 11 and inverter 12;

Wherein, the input end of resolver 3 is connected to the rotor parameter output end of permanent magnet synchronous motor 13, the rotor position output end of resolver 3 is connected to the rotor position data input end of Park transformation module 2; the rotor angular velocity data output end of resolver 3 is connected to The rotor angular velocity data input terminal of the high-order sliding mode observer 4, the observed disturbance value output terminal of the high-order sliding mode observer 4 is connected to the observed disturbance value input terminal of the second-order super-helical sliding mode controller 5; the rotor angular velocity of the resolver 3 The data output end is also connected to the rotor angular velocity input end of the second-order super-helical sliding mode controller 5; the reference data input end of the second-order super-helical sliding mode controller 5 is used to receive the preset given speed of the permanent magnet synchronous motor; the second-order The output end of the super-helix sliding mode controller 5 is connected to the reference data input end of the second comparator 7, and the output end of the second-order super-helix sliding mode controller 5 is also connected to the observation data input end of the high-order sliding mode observer 4;

The input end of the Cark transformation module 1 is connected to the current output end of the permanent magnet synchronous motor 13, and the output end of the Cark transformation module 1 is connected to the input end of the Park transformation module 2;

The d-axis current output end of the permanent magnet synchronous motor of the Park transformation module 2 is connected to the feedback input end of the first comparator 6, and the input end of the first comparator 6 is used to input the d-axis reference current of the permanent magnet synchronous motor. The first comparator 6 The output end of the permanent magnet synchronous motor is connected to the d-axis voltage input end of the permanent magnet synchronous motor of the Park inverse conversion module 10 through the d-axis current loop proportional integral controller 8 of the permanent magnet synchronous motor;

The q-axis current output end of the permanent magnet synchronous motor of the Park transformation module 2 is connected to the feedback input end of the second comparator 7, and the output end of the second comparator 7 is connected to the Park inverter through the q-axis current loop proportional-integral controller 9 of the permanent magnet synchronous motor. The permanent magnet synchronous motor q-axis voltage input terminal of the transformation module 10;

The output end of the Park inverse conversion module 10 is connected to the input end of the pulse width modulation module 11, the output end of the pulse width modulation module 11 is connected to the input end of the inverter 12, and the output end of the inverter 12 is connected to three terminals of the permanent magnet synchronous motor 13. phase voltage input.

The working process of the above-mentioned permanent magnet synchronous motor control system based on the high-order sliding mode method is: to collect the rotor position θ, the rotor angular velocity ω _m and the three-phase currents i _a , i _b and _ic of the permanent magnet synchronous motor (resolver 3 collects To the rotor position θ and rotor angular velocity ω _m of the permanent magnet synchronous motor, the Cark transformation module 1 collects the three-phase currents i _a , i _b and i _c ), the Cark transformation module 1 and the Park transformation module 2 pair the three-phase currents of the permanent magnet synchronous motor 13 The phase currents i _a , i _b and i _c are subjected to Clark transformation and Park transformation to obtain the equivalent currents i _d and i _q of the permanent magnet synchronous motor 13 in the dq-axis coordinate system; The rotor mechanical angular velocity ω _m of the permanent magnet synchronous motor 13 and the given reference speed Get the q-axis given reference current The high-order sliding mode observer 4 uses the collected rotor mechanical angular velocity ω _m of the permanent magnet synchronous motor 13 and the output of the second-order superhelical sliding mode controller 5 to obtain the disturbance d(t) of the permanent magnet synchronous motor control system; The interference of the second-order super-helical sliding mode controller 5 is compensated, and then the q-axis reference current of the permanent magnet synchronous motor is obtained by using the second-order model The first comparator 6 and the second comparator 7 will preset the d-axis reference current of the permanent magnet synchronous motor and the q-axis reference current of the permanent magnet synchronous motor The difference is made with the equivalent current i _d and i _q of the permanent magnet synchronous motor in the dq-axis coordinate system, and the difference is passed through the permanent magnet synchronous motor d-axis current loop proportional integral controller 8, the permanent magnet synchronous motor q-axis current loop ratio The integral controller 9 performs proportional-integral (PI) control to obtain the input voltage u _d and u _q of the permanent magnet synchronous motor 13 in the dq-axis coordinate system; the Park inverse transformation module 10 performs Park inverse transformation on u _d and u _q and outputs them sequentially The three-phase input voltage of the permanent magnet synchronous motor 13 is obtained from the pulse width modulation module 11 and the inverter 12 to drive the permanent magnet synchronous motor 13 to run.

The present invention builds a simulation model based on MATLAB software, and compares the above-mentioned control method of the permanent magnet synchronous motor with a control method based on a traditional terminal sliding mode control (Terminal Sliding Mode Control, TSMC). It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The parameters of the permanent magnet synchronous motor used are as follows: number of pole pairs n _p = 3, rated power P = 3kW, rated current I _N = 6.8A, stator resistance R _s = 0.8Ω, quadrature axis inductance L _q and direct axis inductance L _d is: L _q = L _d = 0.016H, damping coefficient B = 7.403×10 ^-5 N·m·s/rad, torque inertia J=3.78×10 ^-4 kg·m ² , rotor flux linkage ψ _f = 0.35wb. Fig. 3 is a speed waveform diagram of a permanent magnet synchronous motor, Fig. 4 is a schematic diagram of an output torque of a permanent magnet synchronous motor, and Fig. 5 is a schematic diagram of a q-axis current reference value output by a speed loop controller of a permanent magnet synchronous motor. Among them, the black solid line represents the simulation result using the control method based on sliding mode observation, and the gray intermittent line represents the simulation result using the TSMC method.

It can be seen that the simulation results of the high-order sliding mode observation combined with the second-order sliding mode control method are significantly smoother than the simulation results of the TSMC method, the speed and torque response speed is fast, the overshoot is small, and it can stabilize quickly. When the load torque is suddenly added and removed at 0.15s and 0.3s, the high-order sliding mode observation combined with the second-order sliding mode control can respond quickly, output the required torque, and the speed quickly follows the reference speed, while the traditional sliding mode control Large fluctuations. Therefore, the control method of the present invention can significantly improve the operating characteristics of the permanent magnet synchronous motor.

A kind of permanent magnet synchronous motor control method utilizing above-mentioned system, it comprises the steps:

Step 1: Collect the rotor position θ of the permanent magnet synchronous motor 13, the rotor mechanical angular velocity ω _m and the three-phase currents i _a , i _b and i _c , and the three-phase currents i _a , i _b and i _c of the permanent magnet synchronous motor 13 Carry out Clark transformation and Park transformation sequentially by using the Cark transformation module 1 and the Park transformation module 2 to obtain the equivalent current i _d and i _q of the permanent magnet synchronous motor 13 in the dq coordinate system;

According to the vector control theory, each physical quantity of the permanent magnet synchronous motor needs to undergo coordinate transformation, and finally be controlled in the dq coordinate system. The coordinate transformation is shown in Figure 2.

Clark transform:

Park transformation:

Park inverse transformation:

Among them, i _α and i _β are the equivalent currents in the two-phase stationary coordinate system (αβ coordinate system for short), i _a , i _b and i _c are the three-phase currents of the permanent magnet synchronous motor 13, i _d and i _q is the equivalent current of the permanent magnet synchronous motor 13 in the dq axis coordinate system, and θ is the rotor position of the permanent magnet synchronous motor 13;

Set the reference rotor mechanical angular velocity of the permanent magnet synchronous motor 13 and d-axis reference current in, given rotor angular velocity Can be constant or change with time;

Step 2: The rotor mechanical angular velocity ω _m of the collected permanent magnet synchronous motor 13 and the preset given rotational speed of the permanent magnet synchronous motor Bring in the second-order super-helical sliding mode controller 5 to get the output value of the controller:

Among them, ω _m is the actual rotor mechanical angular velocity, For a given rotor mechanical angular velocity, is the first derivative of ω _m , for The first derivative of , for , c is the sliding mode control design parameter, B is the friction damping coefficient of the permanent magnet synchronous motor, J is the moment of inertia of the permanent magnet synchronous motor, k _p is the proportional integral of the q-axis current loop of the permanent magnet synchronous motor (Proportional-Integral, PI ) controller proportional coefficient, _ki is the integral coefficient of the permanent magnet synchronous motor q-axis current loop proportional-integral controller, λ ₁ , λ ₂ are the superhelical sliding mode parameters related to the system dynamic response capability and the magnitude of the disturbance, σ is the speed according to The sliding mode variable of the error and its derivative design, sgn() is a sign function, u is the controller output value of the second-order superhelical sliding mode controller, τ is the integral time variable;

Step 3: Input the rotor mechanical angular velocity ω _m of the collected permanent magnet synchronous motor 13 and the controller output value u of the second-order super-helical sliding mode controller 5 obtained in step 2 into the high-order sliding mode observer 4 to obtain the disturbance observation value :

in, is the first derivative of the motor speed ω _m , is the observed value of motor speed ω _m , ω _m is the actual rotor mechanical angular velocity, for The first derivative of , for derivative of is the interference observation k ₁ , k ₂ , and k ₃ are positive constants, among which k ₁ determines the convergence speed of the observer, the size of k ₂ is determined by the maximum disturbance of the motor system, and k ₃ is determined by the maximum change rate of the system disturbance, is the rotational speed error, B is the friction damping coefficient of the permanent magnet synchronous motor, k _p is the proportional integral controller proportional coefficient of the q-axis current loop of the permanent magnet synchronous motor, J is the moment of inertia of the permanent magnet synchronous motor, k _i is the q of the permanent magnet synchronous motor Shaft current loop proportional integral controller integral coefficient, the observer can obtain accurate observation values of various physical quantities when it is stable;

Step 4: The observed disturbance value observed in step 3 Bringing in the controller output value formula of the second-order superhelical sliding mode controller 5 in step 2, the final output value U of the controller of the second-order superhelical sliding mode controller 5 is obtained:

Step 5: The final output value U of the controller of the second-order superhelical sliding mode controller 5 is combined with the second-order model of the permanent magnet synchronous motor based on the speed to obtain the q-axis reference current of the permanent magnet synchronous motor for:

Among them, U is the final output value of the controller of the second-order super-helical sliding mode controller 5, k _p is the proportional coefficient of the proportional-integral controller of the q-axis current loop of the permanent magnet synchronous motor, J is the moment of inertia of the permanent magnet synchronous motor 13, k _f = 1.5n _p ψ _f /J is the intermediate variable, _ki is the integral coefficient of the permanent magnet synchronous motor q-axis current loop proportional-integral controller, s is the Laplace operator, n _p is the pole pair number of the permanent magnet synchronous motor, ψ _f is the permanent magnet flux linkage of the permanent magnet synchronous motor;

Step 6: Set the d-axis reference current of the permanent magnet synchronous motor After the difference between the q-axis reference current of the permanent magnet synchronous motor and the equivalent current i _d and i _q in the dq axis coordinate system of the permanent magnet synchronous motor, proportional integral control is performed to obtain the permanent magnet synchronous motor 13 in the dq axis coordinate system The input voltage u _d and u _q ;

Step 7: Perform Park inverse transformation on the input voltage u _d and u _q of the permanent magnet synchronous motor 13 in the dq-axis coordinate system to obtain the input voltage u _α and u _β of the permanent magnet synchronous motor 13 in the αβ-axis coordinate system. U _α and u _β are used as carrier signals, and the switching tube control signal of the inverter 12 is obtained through sinusoidal pulse width modulation (Sinusoidal Pulse Width Modulation, SPWM), and the switching tube control signal of the inverter 12 is input to the inverter 12 to control The circuit controls the on and off of the switching device in the inverter 12, and then outputs the three-phase input voltage of the permanent magnet synchronous motor 13, and drives the permanent magnet synchronous motor 13 at a given rotor mechanical angular velocity run.

Since the sampling frequency of the permanent magnet synchronous motor system is very high (on the order of 10 ⁴ ), in order to meet the requirements of the dynamic performance of the system and take into account the disturbance and its change rate, in the above technical solution, the value of λ ₁ is on the order of 10 ³ to 10 ⁶ , and the order of magnitude of λ ₂ is between 10 ^-2 and 10 ¹ ; the order of magnitude of the values of k _p and _ki is between 10 ^-4 and 10 ^-1 .

In the above technical solution, the specific derivation process of the second-order superhelical sliding mode controller is as follows:

The state equation of permanent magnet synchronous motor under dq axis system

Among them, R _s is the stator resistance of the permanent magnet synchronous motor 13, L _d is the direct axis inductance of the permanent magnet synchronous motor 13, L _q is the quadrature axis inductance of the permanent magnet synchronous motor 13, u _d and u _q are the permanent magnet synchronous motor 13 d-axis and q-axis stator voltage, T _L is the load torque of the permanent magnet synchronous motor 13, B is the inherent frictional damping coefficient of the permanent magnet synchronous motor 13, with are respectively the first derivatives of i _d and i _q , n _p represents the number of pole pairs of the permanent magnet synchronous motor, ψ _f represents the rotor flux linkage of the permanent magnet synchronous motor, and J is the inherent moment of inertia of the permanent magnet synchronous motor 13;

Perform Laplace transformation on the third equation in the state equation of the permanent magnet synchronous motor under the dq shaft system:

where i _q (s) is given by Expressed with u _q (s) and brought into formula (3) to get:

Among them, s is the Laplace operator;

Multiply both sides of the above formula by which is:

Perform an inverse Laplace transform on the above formula:

make have to:

The final second-order system:

make

Available In this way, the permanent magnet synchronous motor is deduced as a second-order system, f(t) is the system function part, d(t) is the interference item, and the state variables x ₁ and x ₂ of the second-order speed regulation system of the permanent magnet synchronous motor are defined as:

This is the second-order state equation of the permanent magnet synchronous motor. The design sliding mode variables are:

Derivation of the sliding mode variable can be obtained:

The form of the second-order superhelical sliding mode control algorithm is:

The super-helix algorithm is combined with the sliding mode design method, and the second-order sliding mode control law is:

Combined with the second-order state equation of the permanent magnet synchronous motor, it can be obtained:

Such a second-order sliding mode controller based on the superhelical algorithm is designed as:

d(t) is the disturbance, which will be observed with a high-order sliding mode observer in the next step, and feedback compensation will be performed on the sliding mode controller.

In the above technical solution, the derivation process of the high-order sliding mode observer is as follows:

Assume the most common second-order double-integral system with disturbances:

y=x ₁ (17)

Among them, x ₁ and x ₂ are the state variables of the above-mentioned hypothetical system, y is the output, and ρ ₁ is the disturbance. In order to observe the state quantities of this system, the high-order sliding mode observer can be written as:

Among them z ₁ , z ₂ , z ₃ are correction items. Define the error variable The mathematical expression of the correction item is:

z ₃ =k ₃ sign(e ₁ ) (19)

Among them, the signs of k ₁ , k ₂ , and k ₃ are positive constants. Combining formulas (17), (18) and (19), the system observation error equation can be obtained:

Now redefine the new variable Also assume that the system disturbance ρ ₁ satisfies the Lipschitz condition, and Δ1 is _a positive constant. The observer can be further generalized as:

define variable Observing ω _m , respectively d(t), combined with the second-order system of the permanent magnet synchronous motor, the high-order sliding mode observer of the permanent magnet synchronous motor can be obtained:

Bringing in various physical quantities, the final high-order sliding mode observer of the permanent magnet synchronous motor is:

According to the previous text, is the rotational speed observation value The first derivative of , for derivative of interference for observation Derivatives of , which correspond to

The present invention can overcome the various disturbances faced by the permanent magnet synchronous motor 13 under complex working conditions, resulting in the defects of slow dynamic control response and poor control effect, and provides a fast dynamic response speed, strong anti-interference ability and high control precision. control method of permanent magnet synchronous motor. This method can not only realize the precise control of the permanent magnet synchronous motor, but also realize the fast response of the permanent magnet synchronous motor when the speed and load are changed.

The content not described in detail in this specification belongs to the prior art known to those skilled in the art.

Claims (4)

1. A permanent magnet synchronous motor control system based on high-order sliding mode method, is characterized in that it comprises Cark transformation module (1), Park transformation module (2), rotary transformer (3), high-order sliding mode observer (4), second-order superhelical sliding mode controller (5), first comparator (6), second comparator (7), permanent magnet synchronous motor d-axis current loop proportional integral controller (8), permanent magnet Synchronous motor q-axis current loop proportional-integral controller (9), Park inverse conversion module (10), pulse width modulation module (11) and inverter (12); Wherein, the input terminal of the rotary transformer (3) is connected to the rotor parameter output terminal of the permanent magnet synchronous motor (13), and the rotor position output terminal of the rotary transformer (3) is connected to the rotor position data input terminal of the Park transformation module (2); The rotor angular velocity data output end of (3) is connected to the rotor angular velocity data input end of the high-order sliding mode observer (4), and the observed disturbance value output end of the high-order sliding mode observer (4) is connected to the second-order superhelical sliding mode controller (5) observation disturbance value input end; the rotor angular velocity data output end of resolver (3) also connects the rotor angular velocity input end of second-order superhelical sliding mode controller (5); second-order superhelical sliding mode controller (5) ) is used to receive the preset given speed of permanent magnet synchronous motor; the output end of the second-order super-helical sliding mode controller (5) is connected to the reference data input end of the second comparator (7), and the second-order The output end of the superhelical sliding mode controller (5) is also connected to the observation data input end of the high-order sliding mode observer (4); The input end of the Cark transformation module (1) is connected to the current output end of the permanent magnet synchronous motor (13), and the output end of the Cark transformation module (1) is connected to the input end of the Park transformation module (2); The d-axis current output end of the permanent magnet synchronous motor of the Park transformation module (2) is connected to the feedback input end of the first comparator (6), and the input end of the first comparator (6) is used to input the d-axis reference current of the permanent magnet synchronous motor , the output end of the first comparator (6) is connected to the d-axis voltage input end of the permanent magnet synchronous motor of the Park inverse conversion module (10) through the permanent magnet synchronous motor d axis current loop proportional integral controller (8); The q-axis current output terminal of the permanent magnet synchronous motor of the Park transformation module (2) is connected to the feedback input terminal of the second comparator (7), and the output terminal of the second comparator (7) passes through the proportional integral of the q-axis current loop of the permanent magnet synchronous motor The controller (9) is connected to the permanent magnet synchronous motor q-axis voltage input end of the Park inverse conversion module (10); The output end of the Park inverse conversion module (10) is connected to the input end of the pulse width modulation module (11), and the output end of the pulse width modulation module (11) is connected to the input end of the inverter (12), and the inverter (12) The output end is connected to the three-phase voltage input end of the permanent magnet synchronous motor (13). 2. a permanent magnet synchronous motor control method utilizing the system described in claim 1, is characterized in that, it comprises the steps: Step 1: Collect the rotor position θ of the permanent magnet synchronous motor (13), the rotor mechanical angular velocity ω _m and the three-phase currents i _a , i _b and i _c , and the three-phase currents i _a , i of the permanent magnet synchronous motor (13) _b and i _c carry out Clark transformation and Park transformation successively, obtain the equivalent current i _d and i _q of the permanent magnet synchronous motor (13) under the dq axis coordinate system; Step 2: the rotor mechanical angular velocity ω _m of the collected permanent magnet synchronous motor (13) and the preset given rotational speed of the permanent magnet synchronous motor Bring in the second-order super-helical sliding mode controller (5) to get the output value of the controller: $\begin{array}{c}\mathrm{<span\; class="notranslate">\; u</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; -</span>{\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; \&CenterDot;\&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; Bk</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\mathrm{<span\; class="notranslate">\; J</span>}<span\; class="notranslate">\; )</span>{\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; J</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; B\&omega;</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; J</span>}<span\; class="notranslate">\; )</span>\\ <span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; \&sigma;</span>}{<span\; class="notranslate">\; |</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}}\mathrm{<span\; class="notranslate">\; sgn</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&sigma;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span><span\; class="notranslate">\; \&Integral;</span>{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; sgn</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&sigma;</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; \&tau;</span>}\end{array}$ Among them, ω _m is the actual rotor mechanical angular velocity, For a given rotor mechanical angular velocity, is the first derivative of ω _m , for The first derivative of , for The derivative of , c is the sliding mode control design parameter, B is the friction damping coefficient of the permanent magnet synchronous motor, J is the moment of inertia of the permanent magnet synchronous motor, k _p is the proportional coefficient of the proportional integral controller of the q-axis current loop of the permanent magnet synchronous motor, k _i is the integral coefficient of the proportional-integral controller of the q-axis current loop of the permanent magnet synchronous motor, λ ₁ and λ ₂ are the superhelical sliding mode parameters related to the system dynamic response ability and the magnitude of the disturbance, σ is the sliding mode designed according to the speed error and its derivative Modulus variable, sgn() is a sign function, u is the controller output value of the second-order super-helical sliding mode controller, τ is the integral time variable; Step 3: Input the rotor mechanical angular velocity ω _m of the collected permanent magnet synchronous motor (13) and the controller output value u of the second-order superhelical sliding mode controller (5) obtained in step (2) into the high-order sliding mode observation Device (4) obtains the disturbance observation value: ${\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}{<span\; class="notranslate">\; |</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; g</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>$ ${\stackrel{<span\; class="notranslate">\; \&CenterDot;\&CenterDot;</span>}{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; Bk</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\mathrm{<span\; class="notranslate">\; J</span>}}{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; J</span>}}{\stackrel{<span\; class="notranslate">\; \&Center\; Dot;</span>}{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\mathrm{<span\; class="notranslate">\; B</span>}}{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; J</span>}}{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; u</span>}<span\; class="notranslate">\; +</span>\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}{<span\; class="notranslate">\; |</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; g</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>$ $\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; d</span>}}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; g</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>$ in, is the first derivative of the motor speed ω _m , is the observed value of motor speed ω _m , ω _m is the actual rotor mechanical angular velocity, for The first derivative of , for derivative of is the interference observation k ₁ , k ₂ , and k ₃ are positive constants, among which k ₁ determines the convergence speed of the observer, the size of k ₂ is determined by the maximum disturbance of the motor system, and k ₃ is determined by the maximum change rate of the system disturbance, is the rotational speed error, B is the frictional damping coefficient of the permanent magnet synchronous motor, k _p is the proportion coefficient of the proportional integral controller of the q-axis current loop of the permanent magnet synchronous motor, J is the moment of inertia of the permanent magnet synchronous motor, k _i is the q of the permanent magnet synchronous motor Shaft current loop proportional integral controller integral coefficient, the observer can obtain accurate observation values of various physical quantities when it is stable; Step 4: The observed disturbance value observed in step (3) Bringing into the controller output value formula of the second-order superhelical sliding mode controller (5) in step (2), the final output value U of the controller of the second-order superhelical sliding mode controller (5) is obtained: $\mathrm{<span\; class="notranslate">\; u</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; -</span>{\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; \&CenterDot;\&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; Bk</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\mathrm{<span\; class="notranslate">\; J</span>}}{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; J</span>}}{\stackrel{<span\; class="notranslate">\; \&CenterDot;</span>}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\mathrm{<span\; class="notranslate">\; B</span>}}{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; J</span>}}{\mathrm{<span\; class="notranslate">\; \&omega;</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; +</span>\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; \&sigma;</span>}{<span\; class="notranslate">\; |</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; g</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&sigma;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span><span\; class="notranslate">\; \&Integral;</span>{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; g</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&sigma;</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; \&tau;</span>}$ Step 5: The final output value U of the controller of the second-order superhelical sliding mode controller (5) is combined with the second-order model of the permanent magnet synchronous motor based on the speed to obtain the q-axis reference current of the permanent magnet synchronous motor for: ${\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; q</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; u</span>}<span\; class="notranslate">\; \&CenterDot;</span>\frac{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; J</span>}}{{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; k</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>}$ Among them, U is the final output value of the controller of the second-order superhelical sliding mode controller (5), _kp is the proportional-integral controller proportional coefficient of the q-axis current loop of the permanent magnet synchronous motor, J is the permanent magnet synchronous motor (13) Moment of inertia, k _f = 1.5n _p ψ _f /J is the intermediate variable, _ki is the integral coefficient of the proportional-integral controller of the q-axis current loop of the permanent magnet synchronous motor, s is the Laplace operator, n _p is the pole of the permanent magnet synchronous motor logarithm, ψ _f is the permanent magnet flux linkage of the permanent magnet synchronous motor; Step 6: Set the d-axis reference current of the permanent magnet synchronous motor and the q-axis reference current of the permanent magnet synchronous motor After making difference with the equivalent current i _d and i _q in the dq-axis coordinate system of the permanent magnet synchronous motor (13), the proportional integral control is performed to obtain the input voltage u _d of the permanent magnet synchronous motor (13) in the dq-axis coordinate system and u _q ; Step 7: Perform Park inverse transformation on the input voltage u _d and u _q of the permanent magnet synchronous motor (13) in the dq axis coordinate system, and obtain the input voltage u _α and u q of the permanent magnet synchronous motor (13) in the αβ axis coordinate system u _β , using u _α and u _β as carrier signals, obtain the switching tube control signal of the inverter (12) through sinusoidal pulse width modulation, and input the switching tube control signal of the inverter (12) to the inverter (12 ) control circuit, which controls the on and off of the insulated gate bipolar transistor in the inverter (12), and then outputs the three-phase input voltage of the permanent magnet synchronous motor (13), and drives the permanent magnet synchronous motor (13) according to Given rotor mechanical angular velocity run. 3. The permanent magnet synchronous motor control method according to claim 2, characterized in that: the order of value of λ ₁ is between 10 ³ and 10 ⁶ , and the order of value of λ ₂ is between 10 ^-2 and 10 ¹ between. 4 . The permanent magnet synchronous motor control method according to claim 2 , characterized in that: the values of k _p and _ki have an order of magnitude between 10 ⁻⁴ and 10 ⁻¹ .