Novel model-free superhelix sliding mode control method based on sliding mode disturbance observer

Abstract

The invention discloses a novel model-free super-spiral sliding mode control method based on a sliding mode disturbance observer, and the method comprises the steps: designing a novel model-free super-spiral sliding mode controller of a rotating speed ring based on the combination of a novel super-local model and a second-order super-spiral law; meanwhile, a sliding mode disturbance observer is designed to estimate uncertain and unknown disturbance parts of system parameters in real time and feed back to a novel model-free super-spiral sliding mode controller of a rotating speed ring, so that the rotating speed of the motor is controlled; the controller introduces a linear system state item and a nonlinear disturbance item according to the novel super-local model, establishes a novel super-local model of the system, combines the novel super-local model of the system with a rotating speed ring state equation of the motor, establishes a novel super-local model of a rotating speed ring, and performs the super-local model of the rotating speed ring; and establishing a novel model-free super-spiral sliding mode control law of the rotating speed ring based on the novel super-local model of the rotating speed ring and an observation result of the sliding mode disturbance observer. The influence of external disturbance on the motor is effectively solved, buffeting is weakened, and effective tracking of the given rotating speed can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of motor technology, and in particular to a novel model-free super-helical sliding mode control method based on a sliding mode disturbance observer. Background Art

[0002] Permanent magnet synchronous motor (PMSM) is widely used in electric vehicles, robotics, aerospace and other fields due to its advantages such as simple structure, small size, light weight, high efficiency and high power density.

[0003] Currently, the focus in the motor field is on improving system robustness and interference resistance by reducing the motor's dependence on mathematical models. PI control, due to its simplicity and ease of implementation, is often the preferred control method for servo systems. However, it is susceptible to uncertainties such as external disturbances and parameter perturbations, which reduces control accuracy and makes it difficult to apply to high-performance applications of permanent magnet synchronous motors.

[0004] In recent years, many high-performance control methods have been applied to high-performance applications of permanent magnet synchronous motors, such as adaptive control, optimal control, neural network control, and model predictive control. These control methods rely heavily on the system's mathematical model. However, motors are significantly affected by load disturbances and parameter perturbations during operation, making it difficult to establish high-precision models. Therefore, these methods have certain limitations.

[0005] Model-free control (MFC) can effectively address these issues. This control method does not rely on a mathematical model of the controlled system. Instead, it establishes a hyperlocal model by building an input-output model of the controlled system. A controller is then designed based on this hyperlocal model to achieve high-precision control of the control system. Furthermore, when building a hyperlocal model, the accuracy of the unknown estimation directly impacts the system's control performance. Therefore, an extended state observer (ESO) is combined with the controller. This ESO expands the unknown into the system state, improving estimation accuracy. This approach offers advantages such as high speed, high steady-state accuracy, and robustness. However, the design of the ESO involves numerous parameters, making tuning complex. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a novel model-free super-helical sliding mode control method based on a sliding mode disturbance observer, which effectively solves the influence of external disturbances on the motor, weakens chattering, and can achieve effective tracking of a given speed.

[0007] In order to solve the above technical problems, the present invention provides a new model-free super-helical sliding mode control method based on a sliding mode disturbance observer. Based on the combination of a new super-local model and a second-order super-helical law, a new model-free super-helical sliding mode controller for the speed loop is designed. At the same time, a sliding mode disturbance observer is designed to estimate the uncertain and unknown disturbance parts of the system parameters in real time and provide feedback to the new model-free super-helical sliding mode controller for the speed loop, so as to control the motor speed.

[0008] The method for establishing a new model-free super-helical sliding mode controller for the speed loop is as follows: based on the new super-local model, linear system state terms and nonlinear disturbance terms are introduced to establish a new super-local model of the system for a nonlinear single-input single-output system. The new super-local model of the system is combined with the speed loop state equation of the motor to establish a new super-local model of the speed loop. Based on the observation results of the new super-local model of the speed loop and the sliding mode disturbance observer, a new model-free super-helical sliding mode control law for the speed loop is established.

[0009] Furthermore, the process of establishing the speed loop state equation is as follows:

[0010] First, a conventional motor mathematical model is established, and the parameter perturbations that occur in the actual operation of the motor are introduced to obtain the speed loop state equation of the motor when the motor parameters are perturbed.

[0011] Furthermore, the conventional motor mathematical model is:

[0012]

[0013] Among them, u d is the voltage component of the stator d axis, u q is the voltage component of the stator q axis, i d is the current component of the stator d axis, i q is the current component of the stator q axis, L d is the d-axis inductance of the stator winding, L q is the q-axis inductance of the stator winding, ω e is the electrical angular velocity of the motor, ω m is the mechanical angular velocity, T e is the electromagnetic torque, T L is the load torque, B is the damping coefficient, J is the moment of inertia, n p is the pole pair number, R s is the stator resistance, ψ f is the nominal value of permanent magnet flux linkage;

[0014] The mathematical model of the motor after the reference parameters are perturbed is:

[0015] Where Δu d Δu is the voltage disturbance caused on the d-axis when the motor is perturbed.q is the voltage disturbance caused on the q axis when the motor is perturbed, ΔT e is the disturbance of the output electromagnetic torque when the motor is perturbed, ΔP n is the disturbance caused by the change of the moment of inertia J and the damping coefficient B;

[0016] By combining the conventional motor mathematical model and the motor mathematical model after the reference parameters are perturbed, the speed loop state equation is obtained as follows: Where ΔT L is the load torque disturbance value.

[0017] Furthermore, the new hyperlocal model of the system is established as follows:

[0018] First, establish a hyperlocal model of a nonlinear single-input single-output system: Where y represents the system output; v represents the order of differentiation, v ≥ 1; g(x) is an unknown nonlinear function that depends only on x and satisfies the boundedness of the Lipschitz function; b represents a nonzero constant, and u represents the system input;

[0019] The linear system state term and nonlinear disturbance term are used to define g(x) as: g(x) = βx + F, where β is the state gain of the system and F is a nonlinear bounded function that satisfies the Lebesgue measurability theorem.

[0020] Thus, a new hyperlocal model of the system is obtained: Among them, λ1 is the q-axis current gain to be designed, λ2 is the speed gain to be designed, and F is the uncertainty and unknown disturbance part of the system parameters.

[0021] Furthermore, the new hyperlocal model of the speed loop is established as follows: Where Λ(t) is the rate of change of F.

[0022] Furthermore, the method for establishing the new model-free super-helical sliding mode control law of the speed loop is as follows:

[0023] According to the new super-local model of the speed loop, the reference speed of the motor and the model-free super-helical sliding mode control input are introduced to establish the initial sliding mode control law. Based on the new super-local model of the speed loop and the initial sliding mode control law, the model-free super-helical sliding mode control input is designed. The speed error is selected as the controller state variable and the sliding surface is defined. According to the sliding surface, a new second-order super-helical control law is established. The new model-free super-helical sliding mode control input is obtained through the model-free super-helical sliding mode control input, the sliding surface and the new second-order super-helical control law. Finally, the new model-free super-helical sliding mode control input is combined with the initial sliding mode control law to obtain the new model-free super-helical sliding mode control law for the speed loop.

[0024] Furthermore, the initial sliding mode control law is established as: in, is the motor reference speed, u c The input quantity for the model-free super-helical sliding mode control to be designed;

[0025] The input of model-free super-helical sliding mode control is designed as:

[0026] The new second-order superhelical control law is: in, x′ is the controller state variable, s = x′, k1, k2, and k3 are design parameters to be determined. k1 and k2 are used to ensure that the system can reach stability within a limited time frame, while also reducing chattering and improving the system's resistance to external factors. k3 is used to increase the motor's convergence speed. d is the disturbance generated when the motor's parameters are perturbed.

[0027] The input of the new model-free super-helical sliding mode control is: u c =k1|s| 0.5 sign(s)+k2∫sign(s)dt+k3s-d;

[0028] The new model-free super-helical sliding mode control law of the speed loop after introducing the observation value is:

[0029]

[0030] Furthermore, the design method of the sliding mode disturbance observer is:

[0031] First, the state space equation is constructed. Based on the state equation, the sliding mode disturbance observer equation is designed to obtain the error equation. The sliding mode disturbance observer equation is used to observe the state variables and output variables of the system and to perform feedforward compensation on the motor.

[0032] The integral sliding surface and constant velocity reaching law are designed and combined with the error equation to obtain the sliding mode observer control law.

[0033] Beneficial effects of the present invention:

[0034] 1. Based on the traditional super-local model of the SPMSM speed loop, the known part of the motor system is separated to simplify the design of the model-free super-helical sliding mode controller.

[0035] 2. In order to reduce the impact of chattering on the motor and improve the response speed of the motor system, a new second-order super-helical control law is designed to ensure that the system can reach stability within a limited time range. At the same time, it can weaken chattering and improve the system's resistance to external factors; it can also increase the convergence speed of the motor, that is, effectively ensure the robustness of the system and improve the dynamic response speed of the system.

[0036] 3. The unknown part of the model-free system is observed in real time through a sliding mode disturbance observer, and the new model-free super-helical sliding mode controller of the speed loop is compensated to reduce the chattering problem caused by the introduction of the sliding mode controller and ensure the response speed and control accuracy of the motor system.

[0037] 4. The proposed new model-free super-helical sliding mode control method based on sliding mode disturbance observer not only has a fast response, but also can maintain high-precision control of the motor when the motor is suddenly disturbed by load, thereby improving the system's anti-interference ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the controller structure of the present invention;

[0039] Figure 2 This is the speed response curve of the present invention when the fixed speed is 200r / min;

[0040] Figure 3 This is the speed response curve of the present invention when the given speed is 400r / min;

[0041] Figure 4 This is the speed response curve of the present invention when the given speed is 600r / min;

[0042] Figure 5 This is the speed response curve of the present invention when the load torque is suddenly increased and the given speed is 200r / min;

[0043] Figure 6 This is the speed response curve of the present invention when the load torque is suddenly increased and the given speed is 400r / min;

[0044] Figure 7 This is the speed response curve of the present invention when the load torque is suddenly increased and the given speed is 600 r / min. DETAILED DESCRIPTION

[0045] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0046] Reference Figure 1 As shown, an embodiment of the novel model-free super-helical sliding mode control method based on a sliding mode disturbance observer of the present invention combines second-order super-helical sliding mode control with model-free control based on a novel hyperlocal model. This method is applied to the speed loop of a surface-mounted permanent magnet synchronous motor. This method effectively mitigates the effects of external disturbances on the motor, reduces chattering, and enables efficient tracking of a given speed. Furthermore, a sliding mode disturbance observer is used to estimate the unknown components of the novel hyperlocal model of the speed loop and feed this back to the controller, improving the motor system's anti-interference capability and robustness.

[0047] Specifically, a new model-free super-helical sliding mode controller for the speed loop is established based on the new super-local model. Then, the external disturbance of the motor system and the uncertain part of the motor parameters are observed by the sliding mode disturbance observer, and the observed value is fed back to the new model-free super-helical sliding mode controller for the speed loop. The motor speed is controlled by the new model-free super-helical sliding mode control law of the speed loop. The specific method is as follows:

[0048] First, the mathematical model of SPMSM is developed. When SPMSM works under ideal conditions, the magnetic saturation of the core is ignored, the eddy current and hysteresis loss of the motor are ignored, and parameter perturbation is not considered. Its mathematical equation is:

[0049]

[0050] Among them, u d is the voltage component of the stator d axis, u q is the voltage component of the stator q axis, i d is the current component of the stator d axis, i q is the current component of the stator q axis, L d is the d-axis inductance of the stator winding, L q is the q-axis inductance of the stator winding, ω e is the electrical angular velocity of the motor, ω m is the mechanical angular velocity, T e is the electromagnetic torque, T L is the load torque, B is the damping coefficient, J is the moment of inertia, n p is the pole pair number, R s is the stator resistance, ψ f is the nominal value of the permanent magnet flux.

[0051] However, in actual operation, the motor will be affected by factors such as magnetic circuit saturation and temperature, which will cause perturbations in parameters such as motor resistance and inductance. Therefore, the SPMSM mathematical model can be expressed as:

[0052]

[0053] Where Δu d Δu is the voltage disturbance caused on the d-axis when the motor is perturbed. q is the voltage disturbance caused on the q axis when the motor is perturbed, ΔT e is the disturbance of the output electromagnetic torque when the motor is perturbed, ΔP n is the disturbance caused by the change of the moment of inertia J and the damping coefficient B.

[0054] By combining equations (1) and (2), we can obtain the state equation of the SPMSM speed loop when the motor parameters are perturbed, as shown below:

[0055]

[0056] Where ΔT L is the load torque disturbance value.

[0057] Based on the above state equation, the design of the new model-free super-spiral sliding mode controller for the speed loop, the SPMSM speed loop of this application adopts a new model-free second-order super-spiral sliding mode controller, the structural block diagram is as follows Figure 1 As shown. The feedback controller u in the figure c It is a second-order super-helical sliding mode controller, and the observer uses a sliding mode disturbance observer to observe the unknown part F in the model.

[0058] Specifically, the new hyperlocal model of the SPMSM speed loop is first developed. The hyperlocal model of the nonlinear single-input single-output (SISO) system is expressed as:

[0059]

[0060] Where y represents the system output; v represents the order of differentiation, v ≥ 1; g(x) is an unknown nonlinear function that depends only on x and satisfies the boundedness of the Lipschitz function; b represents a nonzero constant, and u represents the system input.

[0061] According to the new hyperlocal theoretical model, g(x) in Equation (4) can be decomposed into a linear system state term and a nonlinear disturbance term as shown in Equation (5):

[0062] g(x)=βx+F (5)

[0063] Where β is the state gain of the system, and F is a nonlinear bounded function that satisfies the Lebesgue measurability theorem.

[0064] Therefore, a new hyperlocal model of the system described by Equation (4) is established as:

[0065]

[0066] Combining equations (3) and (6), a new super-local model of the speed loop of the SPMSM is established as follows:

[0067]

[0068] Where λ1 is the q-axis current gain to be designed, λ2 is the speed gain to be designed, F is the uncertainty and unknown disturbance part of the system parameters, and Λ(t) is the rate of change of F.

[0069] Then, a new model-free super-helical sliding mode controller for the speed loop is designed, and the initial sliding mode control law is established according to formula (7) as follows:

[0070]

[0071] in, is the motor reference speed, u c Input for the model-free superhelical sliding mode control to be designed.

[0072] According to formula (7) and (8), we can get:

[0073]

[0074] Selecting the speed error as the state variable of the controller, we can get:

[0075]

[0076] Select the sliding surface as:

[0077] s=x′ (11)

[0078] Combining equations (10) and (11), we can obtain:

[0079]

[0080] In order to reduce the impact of chattering on the motor and improve the response speed of the motor system, this application designs a new second-order super-helical control law:

[0081]

[0082] Among them, k1, k2, and k3 are design parameters to be determined. k1 and k2 can ensure that the system can reach stability within a limited time frame, while also reducing vibration and improving the system's resistance to external factors. k3 can increase the convergence speed of the motor. d is the disturbance generated when the motor parameters are perturbed.

[0083] From Equations (10), (12), and (13), the input of the new model-free super-helical sliding mode control can be obtained as:

[0084] u c =k1|s| 0.5 sign(s)+k2∫sign(s)dt+k3s-d (14)

[0085] Combining equations (14) and (8), we can obtain the preliminary new model-free super-helical sliding mode control law for the speed loop:

[0086]

[0087] Proof of stability:

[0088] make Select the following Lyapunov function:

[0089] V(σ)=V(σ1,σ2)=Υ T PY (16)

[0090] Among them, T =[Υ1,Υ2,Υ3]=[|σ| 0.5 sign(σ1),σ1,σ2]

[0091] P is a real symmetric matrix, and the calculation formula is as follows:

[0092]

[0093] Formula (16) is a positive definite function. Taking the derivative of V along the system trajectory, we can get:

[0094]

[0095] in, C=(0 0 1) T , If 2|d|≤τ, τ∈R + , k1, k2 and k3 meet the following conditions:

[0096]

[0097] Then there is

[0098]

[0099] in,

[0100]

[0101]

[0102] In summary, the initial new model-free super-helical sliding mode control law satisfies the sliding mode reachability condition, that is, the new model-free super-helical sliding mode controller for the speed loop designed in this application is asymptotically stable.

[0103] Next, we need to design the sliding mode disturbance observer. First, we construct the state space equation, as shown in Equation (19):

[0104]

[0105] Among them, ω e is the state variable of the system, F is the output variable of the system, and the speed controller output i q * is the input to the system.

[0106] In order to get ω e The observed values of and F are used to perform feedforward compensation on the motor. The designed sliding mode disturbance observer equation is:

[0107]

[0108] Combining equations (19) and (20), we can get the error equation:

[0109]

[0110] Where l is the gain of the sliding mode observer, g(e ω ) is the control law of the observer, e ω is the speed observation error, e F is the perturbation observation error,

[0111] Select the integral sliding surface:

[0112]

[0113] By taking the derivative of formula (22), we can get:

[0114]

[0115] This application uses the function sigmoid(x) to replace the original switching function sign(x) because the sigmoid(x) function is continuous at zero and can improve the chattering problem caused by the switching function sign(x) in the traditional sliding mode observer. The expression of the sigmoid(x) function is as follows:

[0116]

[0117] Here, a is used to adjust the slope of sigmoid(x), and a>0. When the function is near zero, the slope of sigmoid(x) is directly proportional to the value of a. This application selects the sigmoid(x) function with a=2 as the new switching function to ensure that the function changes smoothly near zero.

[0118] Select the constant speed reaching law:

[0119]

[0120] By combining equations (21), (22) and (25), we can get the control law of the designed sliding mode observer:

[0121] g(e ω )=ηsigmoid(s ω )+ce ω(26)

[0122] To ensure that the system state quantity can reach the sliding surface in a short time and remain on the sliding surface, we have:

[0123]

[0124] Combined with formula (27), when the speed observation error is 0, the disturbance term in formula (21) can be expressed as:

[0125]

[0126] Solving the differential equation expressed in equation (28), we can obtain:

[0127] e F =me -pt ,m>0(29)

[0128] In summary, when p>0, the observation error value of the motor system disturbance can approach 0 within a certain period of time, and the speed at which it approaches zero is affected by p.

[0129] The sliding mode disturbance observer observes Substituting into equation (15), the new model-free super-helical sliding mode control law of the speed loop of SPMSM can be obtained as follows:

[0130]

[0131] The stability of the above sliding mode disturbance observer is proved as follows:

[0132] Define the Lyapunov function as:

[0133] Combining equations (21), (23) and (25), and taking the derivative of equation (31), we can obtain:

[0134]

[0135] Therefore, when designing η≥e F hour, The sliding mode disturbance observer is asymptotically stable, and the motor system can reach the sliding mode surface in a finite time. The entire control process of this application is as follows: First, a new model-free super-helical sliding mode controller for the speed loop is established based on the new super-local model. Then, SMDO accurately observes external disturbances in the system and the uncertainties in the motor parameters, and feeds the observed values back to the new model-free super-helical sliding mode controller for the speed loop, achieving precise control of the motor.

[0136] In order to verify the feasibility and effectiveness of the new model-free super-helical sliding mode control method based on sliding mode disturbance observer proposed in this application, a model was established using MATLAB / Simulink, and simulation comparisons were performed with traditional PI control and sliding mode control.

[0137] Table 1 shows the parameters of SPMSM:

[0138]

[0139]

[0140] The SPMSM system of this application adopts i d = 0, the speed controller adopts the NMFSTSMC control method, and the observation value output by the sliding mode disturbance observer can compensate the speed controller. The SPMSM parameters are shown in Table 1, and the control system parameters of the PI, SMC, and NMFSTSMC control methods are shown in Table 2.

[0141] Table 2 shows the control system parameters:

[0142]

[0143] The formulas for determining the values of λ1 and λ2 in the model-free algorithm are: λ1=3n p 2 ψ f / 2J、λ2=B m In the simulation, the current loop uses PI control with the same parameters, and the control performance of the NMFSTSMC, traditional PI control strategy, and SMC control strategy are compared. The comparative simulation content includes: (1) comparing the control performance of the three controllers when the motor starts; (2) comparing the control performance of the three controllers when a sudden external load disturbance is applied when the motor is in a stable state.

[0144] In the simulation experiment, the simulation time is set to 2s, and the given speed is set to 200, 400, and 600r / min respectively. The motor is started without load, and the speed response curves of PI, SMC, and NMFSTSMC in the startup phase are compared. Figure 2 、 Figure 3 and Figure 4As shown in the figure, compared with the PI and SMC control strategies, the proposed method, NMFSTSMC, has a faster response speed during the startup phase, no significant overshoot, and can reach a stable state more quickly. When the motor runs at 200 r / min, the PI method not only takes 0.071 seconds to reach a stable state, but also has a large overshoot. The maximum speed fluctuation after stabilization is approximately 0.889 r / min. The SMC method also takes a long time to reach a stable state, and the overshoot is also relatively large. The NMFSTSMC method only takes 0.0037 seconds to reach the given speed, and the maximum speed fluctuation after stabilization is reduced by approximately 99.4% compared to the PI method. When the motor runs at 400 r / min and 600 r / min, the NMFSTSMC method has basically no speed overshoot, and the approach time is only 0.0046 seconds and 0.005806 seconds, respectively. Both PI and SMC have large overshoots and require a certain amount of time to reach a stable state. Therefore, the NMFSTSMC system has better dynamic response and robustness.

[0145] In order to further verify the anti-interference ability of the control method proposed in this application, when the motor is running to a stable state, a 10N force is suddenly applied at t=1s. ·m The load disturbance continues to act until the end of the simulation, and the speed response curves are as follows: Figure 5 、 Figure 6 and Figure 7 shown.

[0146] observe Figures 5 to 7 As can be seen, at different speeds, the traditional PI control and SMC control strategies experience larger motor fluctuations during sudden load increases and take longer to reach steady state. However, the NMFSTSMC method recovers to the given speed more quickly during sudden load increases, has less overshoot and motor fluctuations than both PI and SMC, and maintains stable operation until the end of the simulation. Furthermore, the NMFSTSMC method, by introducing a sliding mode disturbance observer, improves the control accuracy and anti-interference capability of the permanent magnet synchronous motor.

[0147] In summary, compared with traditional PI control and SMC control, the NMFSTSMC control strategy allows the motor to reach the set speed more quickly at different speeds with virtually no overshoot. Even after a 10 N·m load disturbance, the motor can recover to the set speed in a shorter time. A detailed comparison of these three control strategies is shown in Table 3. The proposed method exhibits superior dynamic response performance, robustness, and steady-state control accuracy.

[0148] Table 3 compares the performance indicators of traditional PI, SMC and NMFSTSMC at different speeds:

[0149]

[0150] This application establishes a new super-local model through the mathematical model of SPMSM under parameter perturbation, and designs a new model-free super-spiral sliding mode controller for the speed loop in combination with the new second-order super-spiral sliding mode control, so as to further improve the robustness of the system and improve the transient steady-state performance of the system. The sliding mode disturbance observer is used to observe the unknown disturbance in the model-free system, and the new model-free super-spiral sliding mode controller of the speed loop is partially compensated to reduce the jitter problem caused by the introduction of the sliding mode controller, thereby ensuring the response speed and control accuracy of the motor system. By comparing with the traditional PI and SMC strategies, it can be obtained that: NMFSTSMC can reach the speed reference value at a faster speed, and there is basically no overshoot. Even in the case of sudden load disturbance, it can quickly recover to the speed reference value and the speed fluctuation is smaller. Simulation shows that NMFSTSMC has strong robustness, faster dynamic response, higher speed accuracy, and can not only weaken the jitter, but also improve the steady-state accuracy.

[0151] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent substitution or modification made by those skilled in the art based on the present invention is within the protection scope of the present invention.

Claims

1. A novel model-free super-helical sliding mode control method based on sliding mode disturbance observer, characterized in that: Based on the combination of a new super-local model and the second-order super-helical law, a new model-free super-helical sliding mode controller for the speed loop is designed. At the same time, a sliding mode disturbance observer is designed to estimate the uncertainties and unknown disturbances of the system parameters in real time and provide feedback to the new model-free super-helical sliding mode controller for the speed loop to control the motor speed. The method for establishing a new model-free super-helical sliding mode controller for the speed loop is as follows: based on the new super-local model, linear system state terms and nonlinear disturbance terms are introduced to establish a new super-local model of the system for a nonlinear single-input single-output system. The new super-local model of the system is combined with the speed loop state equation of the motor to establish a new super-local model of the speed loop. Based on the observation results of the new super-local model of the speed loop and the sliding mode disturbance observer, a new model-free super-helical sliding mode control law for the speed loop is established.

2. The novel model-free super-helical sliding mode control method based on sliding mode disturbance observer according to claim 1, characterized in that: The process of establishing the speed loop state equation is as follows: First, a conventional motor mathematical model is established, and the parameter perturbations that occur in the actual operation of the motor are introduced to obtain the speed loop state equation of the motor when the motor parameters are perturbed.

3. The novel model-free super-helical sliding mode control method based on sliding mode disturbance observer according to claim 1, characterized in that: The mathematical model of a conventional motor is: Among them, u d is the voltage component of the stator d axis, u q is the voltage component of the stator q axis, i d is the current component of the stator d axis, i q is the current component of the stator q axis, L d is the d-axis inductance of the stator winding, L q is the q-axis inductance of the stator winding, ω e is the electrical angular velocity of the motor, ω m is the mechanical angular velocity, T e is the electromagnetic torque, T L is the load torque, B is the damping coefficient, J is the moment of inertia, n p is the pole pair number, R s is the stator resistance, ψ f is the nominal value of permanent magnet flux linkage; The mathematical model of the motor after the reference parameters are perturbed is: Where Δu d Δu is the voltage disturbance caused on the d-axis when the motor is perturbed. q is the voltage disturbance caused on the q axis when the motor is perturbed, ΔT e is the disturbance of the output electromagnetic torque when the motor is perturbed, ΔP n is the disturbance caused by the change of the moment of inertia J and the damping coefficient B; By combining the conventional motor mathematical model and the motor mathematical model after the reference parameters are perturbed, the speed loop state equation is obtained as follows: Where ΔT L is the load torque disturbance value.

4. The novel model-free super-helical sliding mode control method based on sliding mode disturbance observer according to claim 1, characterized in that: The method for establishing the new hyperlocal model of the system is as follows: First, establish a hyperlocal model of a nonlinear single-input single-output system: Where y represents the system output; v represents the order of differentiation, v ≥ 1; g(x) is an unknown nonlinear function that depends only on x and satisfies the boundedness of the Lipschitz function; b represents a nonzero constant, and u represents the system input; The linear system state term and nonlinear disturbance term are used to define g(x) as: g(x) = βx + F, where β is the state gain of the system and F is a nonlinear bounded function that satisfies the Lebesgue measurability theorem. Thus, a new hyperlocal model of the system is obtained: Among them, λ1 is the q-axis current gain to be designed, λ2 is the speed gain to be designed, and F is the uncertainty and unknown disturbance part of the system parameters.

5. The novel model-free super-helical sliding mode control method based on sliding mode disturbance observer according to claim 4, characterized in that: The new hyperlocal model of the speed loop is established as follows: Where Λ(t) is the rate of change of F.

6. The novel model-free super-helical sliding mode control method based on sliding mode disturbance observer according to claim 5, characterized in that: The method for establishing the new model-free super-helical sliding mode control law of the speed loop is as follows: According to the new super-local model of the speed loop, the reference speed of the motor and the model-free super-helical sliding mode control input are introduced to establish the initial sliding mode control law. Based on the new super-local model of the speed loop and the initial sliding mode control law, the model-free super-helical sliding mode control input is designed. The speed error is selected as the controller state variable and the sliding surface is defined. According to the sliding surface, a new second-order super-helical control law is established. The new model-free super-helical sliding mode control input is obtained through the model-free super-helical sliding mode control input, the sliding surface and the new second-order super-helical control law. Finally, the new model-free super-helical sliding mode control input is combined with the initial sliding mode control law to obtain the new model-free super-helical sliding mode control law for the speed loop.

7. The novel model-free super-helical sliding mode control method based on sliding mode disturbance observer according to claim 6, characterized in that: The initial sliding mode control law established is: in, is the motor reference speed, u c The input quantity for the model-free super-helical sliding mode control to be designed; The input of model-free super-helical sliding mode control is designed as: The new second-order superhelical control law is: in, x′ is the controller state variable, s = x′, k1, k2, and k3 are design parameters to be determined. k1 and k2 are used to ensure that the system can reach stability within a limited time frame, while also reducing chattering and improving the system's resistance to external factors. k3 is used to increase the motor's convergence speed. d is the disturbance generated when the motor's parameters are perturbed. The input of the new model-free super-helical sliding mode control is: u c =k1|s| 0.5 sign(s)+k2∫sign(s)dt+k3s-d; The new model-free super-helical sliding mode control law of the speed loop after introducing the observation value is:

8. The novel model-free super-helical sliding mode control method based on sliding mode disturbance observer according to claim 1, characterized in that: The design method of the sliding mode disturbance observer is: First, the state space equation is constructed. Based on the state equation, the sliding mode disturbance observer equation is designed to obtain the error equation. The sliding mode disturbance observer equation is used to observe the state variables and output variables of the system and to perform feedforward compensation on the motor. The integral sliding surface and constant velocity reaching law are designed and combined with the error equation to obtain the sliding mode observer control law.

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