Disturbance Observer-based Speed Tracking Control For Motor

With the continuous progress of the society and the rapid development of science and technology,the motor has been widely used in electronic,mechanical,transportation,medical,aerospace,chemical,military and light industry.The motor is a multivariable nonlinear system with high coupling and structural load,and the traditional control method can not meet the high performance index requirements of the motor control system in the practical application.In recent years,in order to improve the quickness,robustness and stability of the motor speed tracking system,the nonlinear control algorithm has been gradually introduced into the research and application of the motor control system.At the same time,there are still many urgent problems to be solved.In practical engineering,external interference and model uncertainty are inevitable.At this time,the control performance of the system is easily affected and the system is unstable.The main content of this paper is to study the motor speed tracking control method based on disturbance observer.The main work of this paper is as follows:(1)Disturbance observer-based complementary sliding mode control for permanent magnet synchronous linear motor.A complementary sliding mode control method based on disturbance observer is proposed for the adverse factors such as parameter uncertainty,friction and load disturbance in the permanent magnet linear synchronous motor servo system.First,a new complementary sliding mode variable structure controller is designed by combining the generalized sliding mode surface with the complementary sliding mode face.The convergence of the system tracking error can be ensured by the Lyapunov stability theory.At the same time,the switching function takes the saturation function instead of the traditional symbolic function and effectively reduces the chattering of the sliding mode control.Secondly,for the interference and uncertainty of the system,the disturbance observer is constructed by the system state variable,and the observer is fed to the sliding mode controller to compensate the disturbance.(2)Disturbance observer-based feedback control for permanent magnet synchronous motor(PMSM).A hybrid control scheme based on disturbance observer(DOB)and feedback control is proposed for dynamic disturbances originate from PMSM external system.By constructing the disturbance observer,the output of the disturbance observer is introduced into the state feedback controller to counteract the influence of external interference on the system,so as to achieve the purpose of interference suppression.Based on the Lyapunov stability theory and the matrix singular value decomposition technique,the stability condition of the system and the parameter solution method of the controller are obtained.Finally,numerical simulation is carried out to verify the effectiveness of the method.(3)Disturbance observer-based backstepping control for permanent magnet synchronous motor.In order to improve the control performance of the permanent magnet synchronous motor(PMSM)speed control system with external interference,this paper proposes a backstepping control strategy based on the disturbance observer(DOB).Firstly,in view of the dynamic disturbance derived from the PMSM external system,the disturbance observer is constructed by the system state variable,and the design problem of DOB is transformed into the stability of the system error.Further,based on the Lyapunov stability theory,we obtain the existence condition and design method of DOB based on LMI.Then,on the basis of real-time reconstruction of the interference,the backstepping control strategy is used to design the system controller,so that the system has good speed tracking,torque response and interference suppression performance.