Tension anti-interference quality control method based on event triggering mechanism

Abstract

The invention discloses a tension anti-interference control method based on an event trigger mechanism, and the method comprises the steps: S1, building a surface-mounted permanent magnet synchronous servo motor model, describing the built mathematical model, and obtaining the speed and position output of a motor, and the state quantities in a speed loop and a current loop; s2, analyzing the obtained data, and designing a sliding mode controller and a fractional order PID controller; s3, designing a disturbance observer, estimating and compensating the interference in the system through the state quantity of the double loop, and improving the robustness of the system; and S4, designing an event triggering mechanism based on nonlinear sliding mode control, reducing the calculation amount of sliding mode control, reducing the operation demand of the whole system, and completing the control target. According to the invention, the accuracy and response speed of motor control are improved, and the energy efficiency ratio and application range of the system are improved by reducing the calculated amount and optimizing the control algorithm; and in the application occasion of high-precision tension control, the stability of the production process and the product quality can be remarkably improved.

Description

Technical Field

[0001] The invention relates to tension control in a tire manufacturing molding process, in particular to a tension anti-interference control method based on an event trigger mechanism, belonging to the technical field of winding tension control. Background Art

[0002] Winding tension control in the tire manufacturing process is one of the key technologies to ensure tire quality. In this process, the stability and accuracy of winding tension directly affect the performance of the tire, such as high-speed performance, uniformity and dynamic balance. In existing technologies, winding tension control usually adopts PID control theory. By detecting the tension of the crown strip during the winding process, the speed and torque of the drive motor are adjusted in real time to achieve precise control in different winding modes. However, the existing PID control technology still has some problems, such as low control accuracy, low utilization of communication network resources, and insufficient anti-interference ability when facing external interference. At present, researchers have adopted advanced control technology with sliding mode control as the core.

[0003] At present, the problems of existing sliding mode control technology are:

[0004] Sliding mode control is a nonlinear control method that achieves fast, accurate and robust control of the system by designing a sliding surface on which the system state slides. However, sliding mode control may encounter problems such as chattering, initial state sensitivity and computational complexity. Chattering is a fast, small-amplitude oscillation caused by the uncertainty of system parameters and the influence of external disturbances. Initial state sensitivity means that if the initial state deviates far from the sliding surface, it may take a long time for the control system to converge to the sliding surface. The computational complexity problem involves the large amount of calculation required for sliding mode control, especially for high-dimensional systems, the amount of calculation will be even larger.

[0005] From the above, we can see that the nonlinear sliding mode method can be used to reduce chattering, the event trigger mechanism can be used to reduce the computational complexity, and the disturbance observer can be designed to further reduce the interference effect. Through these improvements, the performance and practicality of sliding mode control can be further improved, thereby achieving more accurate and stable winding tension control in the tire manufacturing process. Summary of the invention

[0006] The purpose of the present invention is to provide a tension anti-interference control method based on an event trigger mechanism, which is aimed at the complex control characteristics of the tension control process in the tire production molding link, including external disturbances, insufficient control accuracy, high computational complexity and other problems. In order to solve the problems of inaccurate tension control and complex calculations in the production process, a tension anti-interference quality control technology based on an event trigger mechanism method is used to optimize the control accuracy and stability of the motor. The improved sliding mode control method that combines the event trigger mechanism with the sliding mode control law solves the problem of large computational requirements in the traditional sliding mode control method.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0008] On the one hand, the present invention provides a tension anti-interference control method based on an event trigger mechanism, which comprises the following steps:

[0009] S1: Establish a surface-mounted permanent magnet synchronous servo motor model and describe the constructed mathematical model to obtain the motor's speed and position output, speed loop, and state quantities in the current loop;

[0010] S2: Analyze the data obtained in step S1 and design a sliding mode controller and a fractional-order PID controller;

[0011] S3: Design a disturbance observer to improve the system robustness by estimating the state quantities of the dual loop and compensating for the disturbances in the system;

[0012] S4: Design an event trigger mechanism based on nonlinear sliding mode control to reduce the computational complexity of sliding mode control, thereby reducing the computational requirements of the overall system and achieving the control objectives.

[0013] Furthermore, in step S1, the process of establishing the surface-mounted permanent magnet synchronous servo motor model is as follows:

[0014] S101. Describe the electromagnetic and mechanical characteristics of the servo motor, including the motor's magnetic circuit, circuit, and the interaction between them;

[0015] S102, determining the parameters of the motor;

[0016] S103, establishing dynamic equations of the motor, including a voltage equation, a flux equation, and a torque equation;

[0017] The voltage equation is:

[0018]

[0019] The magnetic flux equation is:

[0020]

[0021] The electromagnetic torque equation is:

[0022]

[0023] The mechanical motion equation is:

[0024]

[0025] Convert it into a mathematical model in the dq coordinate system:

[0026]

[0027] Among them, L A ,L B ,L C is the three-term stator winding self-inductance, M AB ,M AC ,M BA ,M BC ,M CA ,M CB is the stator winding self-inductance. If the number of turns of each phase winding is the same, the self-inductance value is equal to the mutual inductance value, i a ,i b ,i c is the three-phase current, ψ a ,ψ b ,ψ c is the stator three-phase winding flux, ψ f is the rotor permanent magnet excitation flux, θ is the electrical angle; P n is the number of magnetic pole pairs, R s is the stator resistance, T e is the electromagnetic torque, T L is the load torque, T s is the stator inductance, J is the moment of inertia, B is the damping coefficient, ω m is the mechanical angular velocity in rad / s, i d ,i q are the direct axis and quadrature axis currents in the dq coordinate system respectively;

[0028] S104, determine the state quantity of the system. In the speed loop, determine the rotation speed of the motor as the target state quantity of control. In the current loop, determine the three-phase current of the motor or the current component in the converted two-phase stationary coordinate system as the inner loop state quantity of control.

[0029] Furthermore, in step S2, the designed sliding mode controller has a second-order sliding mode control law to improve the dynamic response and robustness of the system.

[0030] Furthermore, in step S2, the designed fractional-order PID controller is:

[0031]

[0032] Among them, u d (t) is the control output along the d-axis, u q (t) is the control output along the q-axis, is the proportional gain of the d-axis to the q-axis, the current error magnification of the control system, is the integral gain of the d-axis and q-axis, the accumulation of control error, is the differential gain between the d-axis and the q-axis, reflecting the effect of the error change rate on the controller. is the d-axis current error, is the q-axis current error, D -λ and D μ They represent fractional-order integration and fractional-order differentiation operations respectively.

[0033] Furthermore, the process of designing a sliding mode controller and a fractional-order PID controller is as follows:

[0034] S201. Design the sliding surface of the sliding mode controller according to the mathematical model of the motor and the control target to ensure that the system state can reach and maintain on the sliding surface:

[0035] Define sliding mode variables:

[0036] where e is the error of the system, is the error change rate, c1 and c2 are weight coefficients; using the dynamic change form of the sliding mode variable given by the reaching law, the design of the control input u needs to make the dynamics of the sliding mode variable s conform to the reaching law to ensure that the system gradually reaches and remains on the sliding surface;

[0037] S202. By switching the control law of the controller, the system state is ensured to slide on the sliding surface and achieve the desired dynamic performance:

[0038] The sliding mode controller includes the equivalent control law and the switching control law: u = u eq +u sw ;

[0039] u eq is an equivalent control term used to keep the system stable on the sliding surface;

[0040] u sw It is the switching control item, which ensures that the system quickly approaches the sliding surface when it is outside the sliding surface, that is, the reaching law;

[0041] In traditional sliding mode control, the reaching law is in the form of:

[0042]

[0043] In order to make the control process smoother, especially when the system approaches the sliding surface, the reaching law is designed as a nonlinear function:

[0044]

[0045] Among them, α and β are parameters less than 1, which control the nonlinear change of the approach speed. When s is small, the approach speed will automatically slow down, thereby reducing chattering; k1 and k2 are adaptive gains, and the controller automatically adjusts the control strength according to the change of system error;

[0046]

[0047] Where ρ1 and ρ2 are adjustment coefficients, and is the basic gain, and the controller gain changes with the error e(t) and the error rate of change Dynamic changes;

[0048] S203, using the fractional order integral and differential order of the multi-order PID controller to adapt to the dynamic characteristics of the motor and improve control accuracy:

[0049] The control law of the fractional-order PID controller of the current loop is:

[0050]

[0051] where u d (t) is the control output along the d-axis, u q (t) is the control output along the q-axis, is the proportional gain of the d-axis to the q-axis, the current error magnification of the control system, is the integral gain of the d-axis and q-axis, the accumulation of control error, is the differential gain between the d-axis and the q-axis, reflecting the effect of the error change rate on the controller. is the d-axis current error, is the q-axis current error, D -λ and D μ They represent fractional-order integral and fractional-order differential operations respectively;

[0052] S204, adjusting the parameters of the PID controller: adjusting the parameters by an optimization algorithm or an experimental method.

[0053] Furthermore, in step S3, the designed disturbance observer includes:

[0054] Define the disturbance observer:

[0055]

[0056] The dynamic equations of the disturbance observer are:

[0057]

[0058] The control law after compensation:

[0059]

[0060] Among them, L q is the q-axis inductance, i q is the q-axis current, R s is the stator resistance, u q is the q-axis control voltage, ω is the motor speed, ψ f is the permanent magnet flux, is the estimated disturbance torque, which is used to compensate for the disturbance in the system; is the estimated state quantity, which here represents the estimated motor speed and q-axis current, f, g are functions that describe the system dynamics, l1, l2, l3 are observer gains, which are used to adjust the observer's response to the system dynamics, is the estimated rotation speed, is the estimated d-axis current.

[0061] Furthermore, in step S4, in order to avoid frequent switching of the system, a hysteresis interval h>0 is introduced as the hysteresis amount of event triggering:

[0062] Let the trigger event time be t k , under the event trigger mechanism, the sliding mode variable modulus |s(x)| is designed as the trigger condition, and the hysteresis region h is introduced; the trigger condition for the hysteresis event trigger is:

[0063] |s(x(t))|≥δ+h

[0064] The conditions for the control signal to stop updating are:

[0065] |s(x(t))|<δ-h

[0066] When the sliding mode variable modulus exceeds δ+h, the control signal update is triggered; when it drops to δ-h, the control signal update is stopped.

[0067] On the other hand, the present invention provides a control system for a surface-mounted permanent magnet synchronous servo motor, comprising:

[0068] A fractional-order PID controller to control the motor's current loop;

[0069] A sliding mode controller to control the motor's speed loop;

[0070] a disturbance observer to estimate and compensate for disturbances in the system;

[0071] An event-triggered controller to reduce the computational effort of control;

[0072] An encoder to provide speed and position outputs of the motor;

[0073] A Park transformation module for converting the three-phase current and voltage of the motor into components in a two-phase rotating coordinate system;

[0074] An inverse Park transformation module, used for converting the current components of the motor in the two-phase rotating coordinate system back to the components in the two-phase stationary coordinate system;

[0075] A Clark transformation module for converting the current and voltage in a three-phase stationary coordinate system into components in a two-phase stationary coordinate system;

[0076] An SVPWM module for generating switching signals for a three-phase inverter.

[0077] The beneficial effects of the present invention are as follows: the present invention provides a surface-mounted permanent magnet synchronous servo motor control method that comprehensively uses advanced control strategies and algorithms, which not only improves the accuracy and response speed of motor control, but also improves the energy efficiency ratio and application scope of the system by reducing the amount of calculation and optimizing the control algorithm. This tension anti-interference control technology based on the event trigger mechanism is particularly suitable for applications that require high-precision tension control, such as tire manufacturing, wire processing, etc., and can significantly improve the stability of the production process and the quality of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] Figure 1 It is a flow chart of the control steps of the surface-mounted permanent magnet synchronous servo motor of the present invention.

[0079] Figure 2 It is a trigger update principle diagram of the event-triggered sliding mode controller of the present invention.

[0080] Figure 3 It is the current loop control block diagram of the present invention.

[0081] Figure 4 It is the overall system design flow chart of the present invention. DETAILED DESCRIPTION

[0082] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0083] Embodiment 1

[0084] like Figures 1 to 4 , a tension anti-interference control method based on event trigger mechanism, comprising the following steps:

[0085] S1: Establish a surface-mounted permanent magnet synchronous servo motor model and describe the constructed mathematical model to obtain the motor's speed and position output, speed loop, and state quantities in the current loop;

[0086] S2: Analyze the data obtained in S1 and design a sliding mode controller and a fractional-order PID controller;

[0087] S3: Design a disturbance observer to improve the system robustness by estimating the state quantities of the dual loop and compensating for the disturbances in the system;

[0088] S4: Design an event trigger mechanism based on the nonlinear sliding mode control law to reduce the computational complexity of the sliding mode control and thus reduce the computational requirements of the overall system.

[0089] In the step S1, a mathematical model based on a surface mounted permanent magnet synchronous servo motor is established, and the specific steps are as follows:

[0090] S10l: Describe the electromagnetic and mechanical characteristics of the servo motor, including the motor's magnetic circuit, electrical circuit, and the interaction between them.

[0091] S102: Determine the parameters of the motor, such as the magnetic flux of the rotor permanent magnet, the resistance and inductance of the stator winding, the moment of inertia and friction coefficient of the motor, etc.

[0092] S103: Establishing the dynamic equations of the motor, including the voltage equation, the flux equation and the torque equation.

[0093] Voltage equation:

[0094]

[0095] Magnetic flux equation:

[0096]

[0097] Electromagnetic torque equation:

[0098]

[0099] Mechanical equation of motion:

[0100]

[0101] Convert it into a mathematical model in the dq coordinate system:

[0102]

[0103] Where L A ,L B ,L C is the three-term stator winding self-inductance, M AB ,M AC,M BA ,M BC ,M CA ,M CB is the stator winding self-inductance. If the number of turns of each phase winding is the same, the self-inductance value is equal to the mutual inductance value, i a ,i b ,i c is the three-phase current, ψ f is the rotor permanent magnet excitation flux, θ is the electrical angle; P n is the number of magnetic pole pairs, T e is the electromagnetic torque, T L is the load torque, T s is the stator inductance, J is the moment of inertia, B is the damping coefficient, ω m is the mechanical angular velocity in rad / s.

[0104] S104: Determine the state quantity of the system. In the speed loop, determine the rotation speed of the motor as the target state quantity of control. In the current loop, determine the three-phase current of the motor or the current component in the converted two-phase stationary coordinate system as the inner loop state quantity of control.

[0105] In step S2, the surface-mounted permanent magnet synchronous servo motor mathematical model obtained in step S1 is used for analysis to design a sliding mode controller and a fractional-order PID controller. The specific steps are as follows:

[0106] S201: Design the sliding surface of the sliding mode controller according to the mathematical model of the motor and the control objective to ensure that the system state can reach and maintain on the sliding surface.

[0107] Define sliding mode variables:

[0108] where e is the error of the system, is the error change rate, c1 and c2 are weight coefficients. Using the dynamic change form of the sliding mode variable given by the reaching law, the design of the control input u needs to make the dynamics of the sliding mode variable s conform to the reaching law to ensure that the system gradually reaches and remains on the sliding surface.

[0109] S202: Design a switching control law of the sliding mode controller to ensure that the system state slides on the sliding surface and achieves the desired dynamic performance.

[0110] The sliding mode controller includes the equivalent control law and the switching control law: u = u eq +u sw

[0111] u eq is an equivalent control term used to keep the system stable on the sliding surface;

[0112] u swIt is a switching control item that ensures that the system quickly approaches the sliding surface when it is outside the sliding surface, which is also the reaching law.

[0113] In traditional sliding mode control, the reaching law is in the form of:

[0114]

[0115] In order to make the control process smoother, especially when the system approaches the sliding surface, the reaching law is designed as a nonlinear function:

[0116]

[0117] Among them, α and β are parameters less than 1, which control the nonlinear change of the approach speed. In this way, when s is small, the approach speed will automatically slow down, thereby reducing the vibration. k1 and k2 are adaptive gains, and the controller can automatically adjust the control strength according to the change of the system error.

[0118]

[0119] Where ρ1 and ρ2 are adjustment coefficients, and is the basic gain, and the controller gain changes with the error e(t) and the error rate of change Dynamic changes.

[0120] S203: Determine the fractional-order integral and differential orders of the fractional-order PID controller to adapt to the dynamic characteristics of the motor and improve control accuracy.

[0121] The control law of the fractional-order PID controller of the current loop is:

[0122]

[0123] where u d (t) is the control output along the d-axis, u q (t) is the control output along the q-axis, is the proportional gain of the d-axis to the q-axis, the current error magnification of the control system, is the integral gain of the d-axis and q-axis, the accumulation of control error, is the differential gain between the d-axis and the q-axis, reflecting the effect of the error change rate on the controller. is the d-axis current error, is the q-axis current error, D -λ and D μ They represent fractional-order integration and fractional-order differentiation operations respectively.

[0124] S204: Design parameters of the fractional-order PID controller, such as proportional gain, integral gain, and differential gain, and perform parameter tuning through an optimization algorithm or an experimental method.

[0125] In step S3, the design of the disturbance observer includes the following specific steps:

[0126] S301: Based on the mathematical model and operating conditions of the motor, a disturbance observer is designed to estimate the uncertainties and external disturbances in the system.

[0127] First define the state of the system:

[0128]

[0129] τ d Considered as extended state (external disturbance)

[0130] Expand the model to:

[0131]

[0132] where f(x1,x2) is the known dynamics of the motor, g(x1,x2,u q ) is the current dynamics of the system.

[0133] Design a linear disturbance observer:

[0134]

[0135] Here is the observed disturbance and can be estimated in real time based on the known motor model and system dynamics.

[0136] S302: Determine an observation strategy and compensation mechanism of a disturbance observer to improve the robustness of the system.

[0137] In order to further improve the robustness of the estimation, we introduce a state observer to estimate the speed and current while observing the disturbance. Its structure is as follows:

[0138] Define a disturbance observer:

[0139]

[0140] The dynamic equation of the observer is:

[0141]

[0142] Where l1, l2, l3 are observer gains.

[0143] Estimating the disturbance through the observer After that, we can compensate for the disturbance in the control law. The control law after compensation is:

[0144]

[0145] Among them, R s is the stator resistance, i q is the q-axis current, L q is the q-axis inductance, ω m is the motor angular velocity, ψ f is the permanent magnet flux.

[0146] Thus, by estimating the disturbance Unknown disturbances in the system can be compensated, thereby improving the robustness of the control system.

[0147] In step S4, the event triggering mechanism based on the nonlinear sliding mode control law has the following specific steps:

[0148] S401: Design event triggering conditions based on nonlinear sliding mode control law to reduce the execution frequency of the control algorithm and reduce the amount of calculation.

[0149] S402: Determine the triggering time and triggering conditions of the event triggering mechanism to ensure control performance while reducing the consumption of communication and computing resources.

[0150] In order to avoid frequent switching of the system, we introduce a hysteresis interval h>0 as the hysteresis of event triggering. Let the trigger event time be t k , under the event trigger mechanism, we design the sliding mode variable modulus |s(x)| as the trigger condition, δ is the threshold of the sliding mode variable, indicating the allowable error limit, and introduces the hysteresis region h. The trigger condition of the hysteresis event trigger is:

[0151] |s(x(t))|≥δ+h

[0152] The conditions for the control signal to stop updating are:

[0153] |s(x(t))|<δ-h

[0154] When the sliding mode variable modulus exceeds δ+h, the control signal update is triggered; when it drops to δ-h, the control signal update is stopped. This design can effectively reduce the frequent switching behavior in the sliding mode control, filter the effective control signal, and save computing and communication resources.

[0155] For surface-mounted permanent magnet synchronous motors using sliding mode control, this method can suppress the unique jitter phenomenon of sliding mode control while saving computing resources; the disturbance observer can reduce the impact of external disturbances on the output, ultimately reducing the amount of calculation of this method and significantly enhancing the anti-interference performance.

[0156] Embodiment 2

[0157] A control system of a surface-mounted permanent magnet synchronous servo motor, which can be used to implement the tension anti-interference control method in the first embodiment, comprises:

[0158] A fractional-order PID controller to control the motor's current loop;

[0159] A sliding mode controller to control the motor's speed loop;

[0160] a disturbance observer to estimate and compensate for disturbances in the system;

[0161] An event-triggered controller to reduce the computational effort of control;

[0162] An encoder to provide speed and position outputs of the motor;

[0163] A Park transformation module for converting the three-phase current and voltage of the motor into components in a two-phase rotating coordinate system;

[0164] An inverse Park transformation module, used for converting the current components of the motor in the two-phase rotating coordinate system back to the components in the two-phase stationary coordinate system;

[0165] A Clark transformation module for converting the current and voltage in a three-phase stationary coordinate system into components in a two-phase stationary coordinate system;

[0166] An SVPWM module for generating switching signals for a three-phase inverter.

[0167] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the protection scope of the present invention in any form, and all technical solutions obtained by equivalent replacement and the like fall within the protection scope of the present invention. The parts not involved in the present invention are the same as the prior art or can be implemented by the prior art.

Claims

1. A tension anti-interference control method based on event trigger mechanism, characterized in that: The steps include: S1: Establish a surface-mounted permanent magnet synchronous servo motor model and describe the constructed mathematical model to obtain the motor's speed and position output, speed loop, and state quantities in the current loop; S2: Analyze the data obtained in step S1 and design a sliding mode controller and a fractional-order PID controller; S3: Design a disturbance observer to improve the system robustness by estimating the state quantities of the dual loop and compensating for the disturbances in the system; S4: Design an event trigger mechanism based on nonlinear sliding mode control to reduce the computational complexity of sliding mode control, thereby reducing the computational requirements of the overall system and achieving the control objectives.

2. The tension anti-interference control method based on event trigger mechanism according to claim 1 is characterized in that: In step S1, the process of establishing the surface-mounted permanent magnet synchronous servo motor model is as follows: S101. Describe the electromagnetic and mechanical characteristics of the servo motor, including the motor's magnetic circuit, circuit, and the interaction between them; S102, determining the parameters of the motor; S103, establishing dynamic equations of the motor, including a voltage equation, a flux equation, and a torque equation; The voltage equation is: The magnetic flux equation is: The electromagnetic torque equation is: The mechanical motion equation is: Convert it into a mathematical model in the dq coordinate system: Among them, L A ,L B ,L C is the three-term stator winding self-inductance, M AB ,M AC ,M BA ,M BC ,M CA ,M CB is the stator winding self-inductance. If the number of turns of each phase winding is the same, the self-inductance value is equal to the mutual inductance value, i a ,i b ,i c is the three-phase current, ψ a ,ψ b ,ψ c is the stator three-phase winding flux, ψ f is the rotor permanent magnet excitation flux, θ is the electrical angle; P n is the number of magnetic pole pairs, R s is the stator resistance, T e is the electromagnetic torque, T L is the load torque, T s is the stator inductance, J is the moment of inertia, B is the damping coefficient, ω m is the mechanical angular velocity in rad / s, i d ,i q are the direct axis and quadrature axis currents in the dq coordinate system respectively; S104, determine the state quantity of the system. In the speed loop, determine the rotation speed of the motor as the target state quantity of control. In the current loop, determine the three-phase current of the motor or the current component in the converted two-phase stationary coordinate system as the inner loop state quantity of control.

3. The tension anti-interference control method based on event trigger mechanism according to claim 1 is characterized in that: In step S2, the designed sliding mode controller has a second-order sliding mode control law to improve the dynamic response and robustness of the system.

4. The tension anti-interference control method based on event trigger mechanism according to claim 1 is characterized in that: In step S2, the designed fractional-order PID controller is: Among them, u d (t) is the control output along the d-axis, u q (t) is the control output along the q-axis, is the proportional gain of the d-axis to the q-axis, the current error magnification of the control system, is the integral gain of the d-axis and q-axis, the accumulation of control error, is the differential gain between the d-axis and the q-axis, reflecting the effect of the error change rate on the controller. is the d-axis current error, is the q-axis current error, D -λ and D μ They represent fractional-order integration and fractional-order differentiation operations respectively.

5. A tension anti-interference control method based on event triggering mechanism according to claim 1, 3 or 4, characterized in that: In step S2, the process of designing the sliding mode controller and the fractional-order PID controller is as follows: S201. Design the sliding surface of the sliding mode controller according to the mathematical model of the motor and the control target to ensure that the system state can reach and maintain on the sliding surface: Define sliding mode variables: where e is the error of the system, is the error change rate, c1 and c2 are weight coefficients; Using the dynamic change form of the sliding mode variable given by the reaching law, the design of the control input u needs to make the dynamics of the sliding mode variable s conform to the reaching law to ensure that the system gradually reaches and remains on the sliding surface; S202. By switching the control law of the controller, the system state is ensured to slide on the sliding surface and achieve the desired dynamic performance: The sliding mode controller includes the equivalent control law and the switching control law: u = u eq +u sw ; u eq is an equivalent control term used to keep the system stable on the sliding surface; u sw It is the switching control item, which ensures that the system quickly approaches the sliding surface when it is outside the sliding surface, that is, the reaching law; In traditional sliding mode control, the reaching law is in the form of: In order to make the control process smoother, especially when the system approaches the sliding surface, the reaching law is designed as a nonlinear function: Among them, α and β are adjustable parameters less than 1, which control the nonlinear change of the approach speed. When s is small, the approach speed will automatically slow down, thereby reducing chattering; k1 and k2 are adaptive gains, and the controller automatically adjusts the control strength according to the change of system error; Where ρ1 and ρ2 are adjustment coefficients, and is the basic gain, and the controller gain changes with the error e(t) and the error rate of change Dynamic changes; S203, using the fractional order integral and differential order of the multi-order PID controller to adapt to the dynamic characteristics of the motor and improve control accuracy: The control law of the fractional-order PID controller of the current loop is: where u d (t) is the control output along the d-axis, u q (t) is the control output along the q-axis, is the proportional gain of the d-axis to the q-axis, the current error magnification of the control system, is the integral gain of the d-axis and q-axis, the accumulation of control error, is the differential gain between the d-axis and the q-axis, reflecting the effect of the error change rate on the controller. is the d-axis current error, is the q-axis current error, D -λ and D μ They represent fractional-order integral and fractional-order differential operations respectively; S204, adjusting the parameters of the PID controller: adjusting the parameters by an optimization algorithm or an experimental method.

6. The tension anti-interference control method based on event trigger mechanism according to claim 1 is characterized in that: In step S3, the designed disturbance observer includes: Define the disturbance observer: The dynamic equations of the disturbance observer are: The control law after compensation: Among them, L q is the q-axis inductance, i q is the q-axis current, R s is the stator resistance, u q is the q-axis control voltage, ω is the motor speed, ψ f is the permanent magnet flux, is the estimated disturbance torque, which is used to compensate for the disturbance in the system; is the estimated state quantity, which here represents the estimated motor speed and q-axis current, f, g are functions that describe the system dynamics, l1, l2, l3 are observer gains, which are used to adjust the observer's response to the system dynamics, is the estimated rotation speed, is the estimated d-axis current.

7. The tension anti-interference control method based on event trigger mechanism according to claim 1 is characterized in that: In step S4, in order to avoid frequent switching of the system, a hysteresis interval h>0 is introduced as the hysteresis amount of event triggering: Let the trigger event time be t k , under the event trigger mechanism, the sliding mode variable modulus |s(x)| is designed as the trigger condition, and the hysteresis region h is introduced; the trigger condition for the hysteresis event trigger is: |s(x(t))|≥δ+h The conditions for the control signal to stop updating are: |s(x(t))|<δ-h Among them, δ is the pre-adjusted event trigger threshold; When the sliding mode variable modulus exceeds δ+h, the control signal update is triggered; when it drops to δ-h, the control signal update is stopped.

8. A control system for a surface mounted permanent magnet synchronous servo motor used in the tension anti-interference control method of claim 1, characterized in that: include: A fractional-order PID controller to control the motor's current loop; A sliding mode controller to control the motor's speed loop; a disturbance observer to estimate and compensate for disturbances in the system; An event-triggered controller is used to reduce the computational complexity of control.

9. The control system of the surface mounted permanent magnet synchronous servo motor according to claim 8, characterized in that: The control system further comprises: An encoder to provide speed and position outputs of the motor; A Park transformation module for converting the three-phase current and voltage of the motor into components in a two-phase rotating coordinate system; An inverse Park transformation module, used for converting the current components of the motor in the two-phase rotating coordinate system back to the components in the two-phase stationary coordinate system; A Clark transformation module for converting the current and voltage in a three-phase stationary coordinate system into components in a two-phase stationary coordinate system; An SVPWM module for generating switching signals for a three-phase inverter.

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