A motor speed control method for suppressing disturbance, storage medium and processor

Abstract

The present application is applicable to the field of synchronous motor control technology, and provides a motor speed control method, storage medium and processor for suppressing disturbances. The method is aimed at the non-periodic and periodic disturbances existing in the permanent magnet synchronous motor system, and based on the generalized extended state observer, fixed time control theory and linear / nonlinear switching control strategy, a generalized extended state observer with fixed time switching is proposed to suppress the non-periodic disturbances of the system. In addition, the present application also proposes a switching quasi-resonant controller based on a quasi-resonant controller and a new switching control strategy to suppress the periodic disturbances of the system. The combination of the two realizes the technical effect of strong robustness speed control of the permanent magnet synchronous motor and improves the operating stability of the permanent magnet synchronous motor. The storage medium storing the method and the processor running the method also have the same technical effect.

Description

Technical Field

[0001] The present application belongs to the technical field of synchronous motor control, and in particular, relates to a permanent magnet synchronous motor speed control method, storage medium and processor for suppressing disturbance. Background Art

[0002] At present, for the non-periodic disturbances of permanent magnet synchronous motors, the widely used control strategies include active disturbance rejection control, intelligent control, robust control and sliding mode control. Among them, the extended state observer, the core of active disturbance rejection control, is an effective method to suppress non-periodic disturbances. However, for time-varying disturbances, the observation effect of the typical extended state observer on the disturbance is not ideal, which limits the accuracy of motor speed control. In order to improve the observation performance of the observer for time-varying disturbances, the generalized extended state observer is usually used. The state estimation error of traditional linear and nonlinear generalized extended state observers can only converge on infinite or finite boundaries. Fixed-time observers are nonlinear observers. When the state estimation error is close to the steady state, the nonlinear adjustment term of the fixed-time observer will cause high-frequency jitter of the estimation error. Quasi-resonant controllers are widely used in practical systems due to their superior performance. However, quasi-resonant controllers will affect the dynamic process of the motor control system and even cause system instability. There are deficiencies in the existing technology. Summary of the invention

[0003] The purpose of the present application is to provide a permanent magnet synchronous motor speed control method, storage medium and processor for suppressing disturbances, aiming to solve the technical problem in the prior art that the periodic and non-periodic disturbances existing during the operation of the motor affect the operating stability.

[0004] In one aspect, the present application provides a motor speed control method for suppressing disturbances, the method comprising the following steps:

[0005] s1. Construct the motor dynamics equations including periodic and non-periodic disturbances;

[0006] s2. Describe the disturbed system based on the motor dynamics equations containing periodic and non-periodic disturbances;

[0007] s3. Expand the disturbed system into n-dimensional form;

[0008] s4. Designing a generalized extended state observer with fixed time switching for the n-dimensional disturbed system;

[0009] s5. Design of a switching quasi-resonant controller for the disturbed system in the form of n dimensions;

[0010] s6. Design a speed control law for the motor system based on the speed error feedback control law, the switch quasi-resonant controller and the fixed-time switching generalized extended state observer.

[0011] On the other hand, the present application also provides a storage medium, which stores a program file capable of implementing the above-mentioned motor speed control method for suppressing disturbances.

[0012] On the other hand, the present application further provides a processor, which is used to run a program, wherein the program executes the above-mentioned motor speed control method for suppressing disturbances when running.

[0013] This application aims at the non-periodic and periodic disturbances existing in the permanent magnet synchronous motor system. Based on the generalized extended state observer, fixed time control theory and linear / nonlinear switching control strategy, a generalized extended state observer with fixed time switching is proposed to suppress the non-periodic disturbances of the system. In addition, this application also proposes a switching quasi-resonant controller based on a quasi-resonant controller and a new switching control strategy to suppress the periodic disturbances of the system. The combination of the two realizes the speed control of the permanent magnet synchronous motor with strong robustness and improves the technical effect of the operation stability of the permanent magnet synchronous motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a motor speed control simulation model diagram using the motor speed control method for suppressing disturbances provided in the first embodiment of the present application;

[0015] Figure 2 is the linear generalized extended state observer estimation error curve;

[0016] Figure 3 is the estimation error curve of the nonlinear generalized extended state observer;

[0017] Figure 4 is the fixed-time generalized extended state observer estimation error curve;

[0018] Figure 5 is a graph of the estimated error of the generalized extended state observer for fixed time switching of the present application;

[0019] Figure 6 This is the steady-state speed curve of the permanent magnet synchronous motor before and after adding the switching quasi-resonant controller;

[0020] Figure 7 This is the Fourier analysis result of the speed curve of the permanent magnet synchronous motor before and after adding the switching quasi-resonant controller;

[0021] Figure 8 This is the simulation result diagram under ramp disturbance;

[0022] Fig. 9 This is the simulation result diagram under sinusoidal disturbance;

[0023] Fig.10 This is a flow chart for implementing the motor speed control method for suppressing disturbances provided in Example 1 of the present application. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0025] The specific implementation of this application is described in detail below in conjunction with specific embodiments:

[0026] Embodiment 1:

[0027] Fig.10 The implementation process of the motor speed control method for suppressing disturbances provided in the first embodiment of the present application is shown. For the convenience of explanation, only the part related to the embodiment of the present application is shown, which is described in detail as follows:

[0028] On the one hand, the present application provides a motor speed control method for suppressing disturbances, the method comprising the following steps:

[0029] s1. Construct the motor dynamics equations including periodic and non-periodic disturbances;

[0030] s2. Describe the disturbed system based on the motor dynamics equations containing periodic and non-periodic disturbances;

[0031] s3. Expand the disturbed system into n-dimensional form;

[0032] s4. Design a generalized extended state observer with fixed-time switching for a perturbed system in n-dimensional form;

[0033] s5. Design a switching quasi-resonant controller for a disturbed system in n-dimensional form;

[0034] s6. Design the speed control law of the motor system based on the speed error feedback control law, the switching quasi-resonant controller and the generalized extended state observer with fixed-time switching.

[0035] Further, step s1 comprises:

[0036] Establish the kinematic equation of permanent magnet synchronous motor:

[0037]

[0038] Among them, ω m is the mechanical angular velocity of the permanent magnet synchronous motor, J is the moment of inertia, T e is the electromagnetic torque, B is the viscous friction coefficient, T L is the load torque.

[0039] For surface mounted permanent magnet synchronous motor, L d =L q Therefore, the electromagnetic torque equation can be expressed as:

[0040]

[0041] Among them, i d and i q are the stator currents of the d-axis and q-axis respectively, L d and L q are the stator inductances of the d-axis and q-axis, ψ f is the permanent magnet flux, n p is the number of magnetic pole pairs, is the electromagnetic torque constant.

[0042] s11. Combine the initial motor kinematic equation with the system parameter change value caused by the non-periodic disturbance to obtain the motor dynamic equation containing the non-periodic disturbance;

[0043] Specifically, the non-periodic disturbances in the permanent magnet synchronous motor system mainly include parameter perturbations and external load disturbances. Considering the impact of non-periodic disturbances on the system, the dynamic equation of the permanent magnet synchronous motor can be expressed as:

[0044]

[0045] Among them, J 0 Indicates the original value of the motor's moment of inertia; K t0 Indicates the original value of the electromagnetic torque constant, B 0 Represents the original value of the viscous friction coefficient; ΔJ = JJ 0 Indicates the change in the motor's moment of inertia, ΔK t =K t -K t0 Indicates the change in electromagnetic torque constant, ΔB = BB 0 Indicates the change in the viscous friction coefficient.

[0046] s12. The torque pulsation caused by the periodic disturbance is combined with the motor dynamics equation containing the non-periodic disturbance to obtain the motor dynamics equation containing the periodic disturbance and the non-periodic disturbance.

[0047] Specifically, the periodic disturbances in the permanent magnet synchronous motor system mainly include flux harmonics, cogging torque, inverter nonlinearity, and current measurement errors. Considering the impact of periodic disturbances on the system, the dynamic equation of the permanent magnet synchronous motor can be expressed as:

[0048]

[0049] Among them, torque ripple

[0050] Among them, T h is the torque ripple caused by periodic disturbance, T 1 , T 2 and T 6n are the amplitudes of the 1st, 2nd and 6nth torque harmonic components, θ 1 ,θ 2 and θ 6n are the phase angles of the 1st, 2nd and 6nth torque harmonic components, θ e is the electrical angle of the permanent magnet synchronous motor.

[0051] Furthermore, non-periodic disturbances include parameter perturbations and external load disturbances; periodic disturbances mainly include flux harmonics, cogging torque, inverter nonlinearity and current measurement errors.

[0052] Furthermore, the disturbed system at least includes state variables of the system, control inputs of the system, system outputs and total disturbances of the system.

[0053] Specifically, the permanent magnet synchronous motor dynamics equation (4) can be equivalent to the following disturbed system:

[0054]

[0055] Among them, x 1 =ω m is the state variable of the system, u=i qref is the control input of the system, i qref is the motor q-axis current reference, y = ω m is the system output, is a constant, is the total disturbance of the system.

[0056] In this application, the permanent magnet synchronous motor system is equivalent to the disturbed system represented by the above formula (6) in order to facilitate the expression and design of the generalized extended state observer with fixed time switching. The equivalent disturbed system is another expression form of the permanent magnet synchronous motor system. The two should be regarded as the same system in essence.

[0057] Based on this, for non-periodic disturbances in permanent magnet synchronous motor systems, the present application proposes a generalized extended state observer with fixed-time switching to estimate and compensate for the disturbances.

[0058] The purpose of expanding the disturbed system into an n-dimensional form in this application is to establish a generalized extended state observer with fixed time switching, where "generalized" means "high-order".

[0059] Specifically, in order to effectively observe the time-varying non-periodic disturbances in the permanent magnet synchronous motor system, based on the design idea of ​​the generalized extended state observer, a high-order fixed-time switching generalized extended state observer is established. First, the disturbed system (6) needs to be expanded into an n-dimensional form, which can be expressed as:

[0060]

[0061] in, is the first-order derivative of the total disturbance d, d (n-2) represents the n-2nd derivative of the total disturbance d, d (n-1) represents the n-1th order derivative of the total disturbance d, and satisfies is d (n-1) The upper bound of .

[0062] The first-order disturbed system represented by formula (6) is expanded into an n-order disturbed system represented by formula (7), and then an n-order generalized extended state observer of the first-order disturbed system is established based on the n-order disturbed system (represented by formula (8)). The expansion into an n-dimensional form is a transition process.

[0063] Among them are the estimated value of the state vector, the estimated error of the estimated value, a positive constant related to the bandwidth of the generalized extended state observer with fixed time switching, the error correction term for linear / nonlinear switching, and the linear / nonlinear switching point.

[0064] Specifically, based on the expansion of the first-order disturbed system into an n-dimensional disturbed system, the fixed-time switching generalized extended state observer of the n-dimensional disturbed system can be designed as:

[0065]

[0066] Among them, the error correction term

[0067] in, is the estimated vector of the state vector x, is the state x 1 The estimation error, K = [k 1 k 2 …k n ] T is the gain vector of the observer, is the error correction term for the observer’s linear / nonlinear switching, δ∈(0,1) is the observer’s linear / nonlinear switching point, sign(·) represents the sign function, and γ∈(1,+∞) are constant parameters related to the powers of the error correction terms, and γ i =iγ-(i-1)(i=1,2,…,n) is the power of each error correction term, ω 0 ≥1 is a positive constant related to the observer bandwidth.

[0068] Compared with the traditional linear / nonlinear extended state observer, the above-mentioned fixed-time switching generalized extended state observer adopts the design concept of generalized observer to design the observer into a high-order form, which can well estimate the time-varying disturbance; the fixed-time control theory is used to design the error correction term (9), which can make the fixed-time switching generalized extended state observer converge within a fixed time; the linear / nonlinear switching control strategy is used to converge at the linear / nonlinear switching point The nonlinear error correction term is switched to a linear error correction term, thereby avoiding the amplification chattering problem existing in the traditional nonlinear extended state observer in the steady state.

[0069] The linear / nonlinear switching point δ should be selected based on the maximum steady-state error after the generalized extended state observer with fixed-time switching enters the steady state.

[0070] When the estimated error converges to the linear-nonlinear switching point, the nonlinear fixed-time observer switches to the linear observer; that is, when the estimated error Converge to When , the nonlinear fixed-time observer switches to a linear observer, which suppresses the high-frequency chattering phenomenon caused by the fixed-time observer in steady state.

[0071] The generalized extended state observer with fixed-time switching is based on the homogeneity theory and the fixed-time control principle. When the estimated error is greater than or equal to 1, the estimated error converges to 1 after the first fixed time, and then converges to the switching point between linear and nonlinear after the second fixed time. That is, when the estimated error When the observer estimates the error Can be in the first fixed time τ 1 =4 / ω 0 (γ-1) converges to Then, at the second fixed time Converges to the switching point

[0072] Furthermore, the convergence time of the estimation error of the generalized extended state observer with fixed-time switching is a total fixed time, and the total fixed time is equal to the sum of the first fixed time and the second fixed time.

[0073] In the specific implementation, the fixed-time switching generalized extended state observer (8) can make the estimation error within the fixed time τ = τ1 +τ 2 Converges to the switching point And its convergence time τ is independent of the initial estimation error of the system. It solves the problem of slow convergence speed and long convergence time of the observer when the initial estimation error of the system is large, improves the observation speed of the observer, and improves the dynamic performance and robustness of the permanent magnet synchronous motor system.

[0074] Further, the switch quasi-resonant controller includes: speed error, motor mechanical angular velocity reference input, resonance gain, damping frequency, resonance frequency and switching point of the resonance controller on and off;

[0075] When the disturbed system is in a dynamic process, the absolute value of the speed error is greater than the value of the switching point of the resonant controller being turned on and off, and the switching quasi-resonant controller is turned off, which has no effect on the disturbed system; when the disturbed system is close to a steady state, the absolute value of the speed error is less than or equal to the value of the switching point of the resonant controller being turned on and off; the switching quasi-resonant controller is turned on, acting on the disturbed system to suppress the speed pulsation caused by periodic disturbances.

[0076] Specifically, the present application targets the periodic disturbance in the permanent magnet synchronous motor system and uses a switching quasi-resonant controller to suppress the speed pulsation caused by the harmonic component of the torque pulsation. The transfer function of the switching quasi-resonant controller is as follows:

[0077]

[0078] Where e = ω mref -ω m is the speed error, ω mref is the motor mechanical angular velocity reference input, k r is the resonant gain, ω c is the damping frequency, ω h is the resonant frequency, sign(·) represents the sign function, and σ is the switching point between the on and off of the resonant controller. For the above-mentioned switching quasi-resonant controller, when the system is in a dynamic process, |e|>σ, the transfer function G of the quasi-resonant controller is QRC (s) = 0, the resonant controller has no effect on the system; when the system is close to steady state, |e| ≤ σ, the transfer function of the quasi-resonant controller is The resonant controller acts on the system to suppress the speed pulsation caused by periodic disturbances and improve the steady-state performance of the permanent magnet synchronous motor system. The switching point σ of the resonant controller is selected according to the maximum steady-state error after the actual system enters the steady state. After a lot of analysis and verification, when σ is selected as 10 times the maximum steady-state error, the switching quasi-resonant controller has a good effect.

[0079] Furthermore, the speed error feedback control law is the product of the proportional coefficient of the speed error feedback control and the speed error.

[0080] In the specific implementation process of step s6, in order to make the permanent magnet synchronous motor stably track the mechanical angular velocity reference, the speed error feedback control law is designed as follows:

[0081] u 0 =k p (ω mref -ω m ); (11)

[0082] Among them, u 0 is the speed error feedback control law, k p is the proportional coefficient of speed error feedback control.

[0083] Furthermore, the output of the switching quasi-resonant controller is compensated to the speed error feedback control law to suppress the speed pulsation caused by periodic disturbances. After adding the output compensation of the switching quasi-resonant controller, the speed error feedback control law can be rewritten as:

[0084] u 0 =k p (ω mref -ω m )+C QRC ; (15)

[0085] Among them, C QRC =L -1 [G QRC (s)E(s)] is the output of the switching quasi-resonant controller, L -1 [G QRC (s)E(s)] is expressed as G QRC (s) is the inverse Laplace transform of E(s), where E(s) is the Laplace transform of the velocity error e.

[0086] Furthermore, the total disturbance estimated by the generalized extended state observer with fixed time switching is compensated to the speed feedback control law (15) to suppress non-periodic disturbances and improve the robustness and stability of the permanent magnet synchronous motor system. Finally, the permanent magnet synchronous motor speed control law is obtained as follows:

[0087]

[0088] The speed control law (16) of the motor system designed based on the speed error feedback control law, the switch quasi-resonant controller and the generalized extended state observer with fixed time switching is applied to the permanent magnet synchronous motor speed control system, thereby realizing the strong robust speed control of the permanent magnet synchronous motor and improving the technical effect of the operation stability of the permanent magnet synchronous motor.

[0089] Embodiment 2:

[0090] On the other hand, the present application also provides a storage medium, which stores a program file capable of implementing the above-mentioned motor speed control method for suppressing disturbances.

[0091] A person skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, such as ROM / RAM, disk, CD-ROM, etc.

[0092] Embodiment three:

[0093] On the other hand, the present application further provides a processor, which is used to run a program, wherein the program executes the above-mentioned motor speed control method for suppressing disturbances when running.

[0094] In the embodiment of the present application, the motor speed control method for suppressing disturbance can be implemented by corresponding hardware or software units, and each unit can be an independent software or hardware unit, or can be integrated into a software or hardware unit, which is not intended to limit the present application. The specific implementation of each unit can refer to the description of embodiment 1, which will not be repeated here.

[0095] Embodiment 4:

[0096] In the specific implementation process, the motor speed control method of the present application solves the technical problem of suppressing the periodic and non-periodic disturbances of the system, and achieves the technical effect of strong robustness speed control of the permanent magnet synchronous motor. The following is a detailed description through a specific comparison and verification process.

[0097] In order to verify the effectiveness of the permanent magnet synchronous motor speed control strategy based on the generalized extended state observer with fixed time switching proposed in this application, the effectiveness of the proposed method is verified by combining several sets of comparative simulation results.

[0098] In the simulation experiment, in order to balance the anti-interference and anti-noise capabilities of the system, the order of the fixed-time switching generalized extended state observer is selected as n = 3. In addition, only the 6th and 12th torque pulsation harmonic components that mainly exist in the permanent magnet synchronous motor system are considered here. The simulation model of permanent magnet synchronous motor speed control based on the fixed-time switching generalized extended state observer and the switch quasi-resonant controller is shown in Figure 1 As shown. Figure 1 In the simulation model shown, first, the mechanical angular velocity reference input of the permanent magnet synchronous motor is set to ω mref , i is used for permanent magnet synchronous motor dref=0 control strategy, where i dref is the stator current reference of the motor d axis; secondly, the electrical angle θ of the motor is obtained by using the encoder e and mechanical angular velocity ω m , electrical angle θ e For coordinate transformation, mechanical angular velocity ω m The generalized extended state observer, switch quasi-resonant controller and speed error feedback control law are designed for fixed-time switching; Next, the mechanical angular velocity ω m , estimated value of mechanical angular velocity The output u of the speed control law is the q-axis stator current reference i of the motor qref The input is fed into the generalized extended state observer with fixed-time switching to obtain an estimate of the total disturbance Using the mechanical angular velocity reference ω mref and mechanical angular velocity ω m The mechanical angular velocity error e is obtained by subtraction, and the angular velocity error e is input to the switch quasi-resonant controller to obtain the speed error feedback control law u 0 , further, the estimated value of the total disturbance Compensation to the speed error feedback control law u 0 Get the speed control law u, and then get the motor's q-axis stator current reference i qref ; Then, the motor's a-phase, b-phase and c-phase currents i are obtained through the current sensor a 、i b and i c , and then the actual current i of the motor d-axis and q-axis is obtained through coordinate transformation d and i q , the PI controller is used to obtain the voltage u of the motor d-axis and q-axis. d and u q Furthermore, the switching signal state vector S of the inverter is obtained by coordinate transformation and SVPWM pulse modulation method. abc ; Finally, the inverter is based on the DC voltage u DC And the switch signal outputs three-phase current to the motor to drive the permanent magnet synchronous motor to run.

[0099] First, in order to verify the observation performance of the generalized extended state observer with fixed time switching proposed in this application, the following experimental configuration is performed: during the period from 0s to 5s, the motor mechanical angular velocity is set to ω m =1500rpm, the total disturbance imposed by the system is d=4N·m; at 0s, the mechanical angular velocity estimation of the observer is set The observer's initial total disturbance estimate Based on the above experimental configuration, Figure 2 , 3, 4 and 5 give the state estimation error curves of the linear generalized extended state observer, the nonlinear generalized extended state observer, the fixed-time generalized extended state observer and the fixed-time switching generalized extended state observer, respectively.

[0100] Further, in Figure 2 , 3 , 4 and 5, the horizontal axis represents time and the vertical axis represents represents the velocity estimation error of the observer, Represents the total disturbance estimation error of the observer. Figure 2 , 3 As shown in 5, Figure 5 The time it takes for the speed estimation error curve and the total disturbance estimation error curve to converge to zero is the shortest, that is, the state estimation error of the generalized extended state observer with fixed time switching converges the fastest.

[0101] Therefore, the fixed-time switching generalized extended state observer proposed in this application based on the fixed-time control theory and the linear-nonlinear switching control strategy has a faster observation capability compared with the linear and nonlinear generalized extended state observers. Figure 4 and 5 As shown, Figure 5 The jitter amplitude of the velocity estimation error and disturbance estimation error in is less than Figure 4 Therefore, the control strategy of linear and nonlinear switching used in this application to suppress the chattering problem of the fixed-time generalized extended state observer is an effective solution. Therefore, the fixed-time switching generalized extended state observer proposed in this application has good dynamic performance and steady-state performance.

[0102] Then, in order to verify the suppression effect of the switching quasi-resonant controller proposed in this application on speed pulsation, Figure 6 and 7 The motor mechanical angular velocity is given as ω m =100rpm, the steady-state speed curve and corresponding Fourier analysis results of the permanent magnet synchronous motor speed control system before and after adding the switching quasi-resonant controller. Figure 6 In the figure, the horizontal axis represents time and the vertical axis represents ω. m Represents the mechanical angular velocity of the motor. The curve in the upper part is the mechanical angular velocity curve before adding the switch quasi-resonant controller, and the curve in the lower part is the mechanical angular velocity curve after adding the switch quasi-resonant controller. Figure 6 As shown, the fluctuation amplitude of the motor mechanical angular velocity curve is small after adding the switching quasi-resonant controller, that is, the speed pulsation of the motor is effectively suppressed.

[0103] also, Figure 7 Given Figure 6Fourier analysis results of two mechanical angular velocity curves before and after adding the switching quasi-resonant controller. Figure 7 In the figure, the horizontal axis represents the frequency of the speed pulsation harmonic component existing in the motor mechanical angular velocity, the vertical axis Mag represents the amplitude of the harmonic component, DC = 100 represents the motor mechanical angular velocity amplitude of 100rpm, THD represents the total harmonic distortion, the left half is the Fourier analysis result of the mechanical angular velocity curve before adding the switch quasi-resonant controller, and the right half is the Fourier analysis result of the mechanical angular velocity curve after adding the switch quasi-resonant controller. Figure 7 As shown in the Fourier analysis results, the amplitudes of the 6th and 12th speed pulsation harmonic components of the mechanical angular velocity are reduced after the switching quasi-resonant controller is added. Compared with before the switching quasi-resonant controller is added, the total harmonic distortion THD of the mechanical angular velocity of the motor is reduced by 0.04%.

[0104] Finally, in order to further verify the control performance of the permanent magnet synchronous motor speed control strategy based on the fixed time switching generalized extended state observer proposed in this application, given the mechanical angular velocity reference ω of the motor mref =100rpm, Figure 8 and 9 The total disturbance curve estimated by the observer and the mechanical angular velocity curve of the motor are given when the total disturbance of the system is a ramp disturbance and a sinusoidal disturbance respectively. Figure 8 and 9 As shown in , for time-varying disturbances, the generalized extended state observer with fixed time switching proposed in this application can estimate them well, thereby controlling the impact of disturbances on speed within a very small fluctuation range. It is worth noting that the bandwidth of the observer will change with the parameter ω 0 , and the observation performance of the observer will be further improved.

[0105] In summary, the permanent magnet synchronous motor speed control strategy based on the generalized extended state observer with fixed time switching proposed in this application can achieve strong robust speed control of the permanent magnet synchronous motor when there are periodic and non-periodic disturbances in the permanent magnet synchronous motor system.

[0106] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A motor speed control method for suppressing disturbances, characterized in that: The method comprises the following steps: s1. Construct the motor dynamics equations including periodic and non-periodic disturbances; s2. Describe the disturbed system based on the motor dynamics equations containing periodic and non-periodic disturbances; s3. Expand the disturbed system into n-dimensional form; s4. Designing a generalized extended state observer with fixed time switching for the n-dimensional disturbed system; s5. Design of a switching quasi-resonant controller for the disturbed system in the form of n dimensions; s6. Design a speed control law for the motor system based on the speed error feedback control law, the switch quasi-resonant controller and the generalized extended state observer with fixed time switching; In step s4, the fixed-time switching generalized extended state observer is designed as: Among them, the error correction term in, is the estimated vector of the state vector x, is the estimation error of state x1, K=[k1 k2 … k n ] T is the gain vector of the observer, (i=1,2,...,n) is the error correction term for the observer linear / nonlinear switching, δ∈(0,1) is the switching point of the observer linear / nonlinear, sign(·) represents the sign function, θ∈(1-1 / n,1) and γ∈(1,+∞) are constant parameters related to the power of each error correction term, θ i =iθ-(i-1) and γ i =iγ-(i-1)(i=1,2,…,n) is the power of each error correction term, ω0≥1 is a positive constant related to the observer bandwidth; ω m is the mechanical angular velocity of the permanent magnet synchronous motor; is the first-order derivative of the total disturbance d, d (n-2) represents the n-2nd order derivative of the total disturbance d, d (n-1) represents the n-1th order derivative of the total disturbance d; In step s5, the transfer function of the switch quasi-resonant controller is as follows: Where e = ω mref -ω m is the speed error, ω mref is the motor mechanical angular velocity reference input, k r is the resonant gain, ω c is the damping frequency, ω h is the resonant frequency, sign(·) represents the sign function, σ is the switching point between the on and off of the resonant controller; for the switching quasi-resonant controller, when the system is in a dynamic process, |e|>σ, the transfer function G of the quasi-resonant controller is QRC (s) = 0, the resonant controller has no effect on the system; when the system is close to steady state, |e| ≤ σ, the transfer function of the quasi-resonant controller is The resonant controller acts on the system to suppress the speed pulsation caused by periodic disturbances; In step s6, the speed control law is: Among them, u0 is the speed error feedback control law; is the estimated value of the total disturbance; b0 is a constant; u0 = k p (ω mref -ω m )+C QRC ; (15) Among them, C QRC =L -1 [G QRC (s)E(s)] is the output of the switching quasi-resonant controller, L -1 [G QRC (s)E(s)] is expressed as G QRC (s) Laplace inverse transform of E(s), where E(s) is the Laplace transform of the velocity error e; k p is the proportional coefficient of speed error feedback control.

2. The method according to claim 1, characterized in that The step s1 comprises: s11. Combine the initial motor kinematic equation with the system parameter change value caused by the non-periodic disturbance to obtain the motor dynamic equation containing the non-periodic disturbance; s12. The torque pulsation caused by the periodic disturbance is combined with the motor dynamics equation containing the non-periodic disturbance to obtain the motor dynamics equation containing the periodic disturbance and the non-periodic disturbance.

3. The method according to claim 2, characterized in that The non-periodic disturbances include parameter perturbations and external load disturbances; the periodic disturbances include flux harmonics, cogging torque, inverter nonlinearity and current measurement errors.

4. The method according to claim 1, characterized in that The disturbed system at least includes the state variables of the system, the control input of the system, the system output and the total disturbance of the system.

5. The method according to claim 4, characterized in that The fixed-time switching generalized extended state observer comprises: an estimated value of the state variable, an estimated error of the estimated value, a positive constant related to a bandwidth of the fixed-time switching generalized extended state observer, an error correction term for linear / nonlinear switching, and a linear / nonlinear switching point; When the estimation error of the fixed-time switching generalized extended state observer converges to the linear and nonlinear switching point, the nonlinear fixed-time observer switches to the linear observer; When the estimation error of the generalized extended state observer switched at a fixed time is greater than or equal to 1, the estimation error converges to 1 within a first fixed time, and then converges to the linear / nonlinear switching point within a second fixed time.

6. The method according to claim 5, characterized in that The convergence time of the estimation error of the generalized extended state observer with fixed-time switching is a total fixed time, and the total fixed time is equal to the sum of the first fixed time and the second fixed time.

7. The method according to claim 1, characterized in that The switch quasi-resonant controller includes: speed error, motor mechanical angular velocity reference input, resonance gain, damping frequency, resonance frequency and switching point of the resonance controller on and off; When the disturbed system is in a dynamic process, the absolute value of the speed error is greater than the value of the switching point between the resonant controller and the on-off switch, and the switching quasi-resonant controller is turned off, which has no effect on the disturbed system; when the disturbed system is close to a steady state, the absolute value of the speed error is less than or equal to the value of the switching point between the resonant controller and the on-off switch; the switching quasi-resonant controller is turned on, acting on the disturbed system to suppress speed pulsations caused by periodic disturbances.

8. The method according to claim 1, characterized in that The speed error feedback control law is the product of the proportionality coefficient of the speed error feedback control and the speed error.

9. A storage medium, characterized in that: The storage medium stores a program file capable of implementing the motor speed control method for suppressing disturbances as described in any one of claims 1 to 8.

10. A processor, characterized in that: The processor is used to run a program, wherein the program, when running, executes the motor speed control method for suppressing disturbances as described in any one of claims 1 to 8.

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