Active Disturbance Rejection Backstepping Control Of Asynchronous Motor Based On Coordination And Optimization Of Flux Linkage

Aiming at the unknown load problem in the speed control system of induction motor,based on the backstepping control strategy,this paper applies the adaptive algorithm to the uncertain load torque,designs a novel adaptive load torque observer,and accurately estimates the change of unknown load online in real-time.At the same time,the load disturbance attenuation performance of the system is improved by combining the backstepping control and the active disturbance rejection control strategy,and the high performance speed tracking control of the induction motor is realized.In the efficiency optimization control of rotor flux,a coordinated optimization control algorithm based on speed error is designed,which solves the problem that the switching time point of given rotor flux and optimal rotor flux is difficult to grasp.The induction motor platform based on LINKS-RT experiment system verifies the validity of this topic.Firstly,the purpose and significance of this research are explained,and the mathematical model and vector control principle of induction motor are introduced.Secondly,combining the backstepping control strategy with the adaptive mechanism,the adaptive law of the load is designed,and a novel adaptive load torque observer is built,which can accurately estimate the change of the load and improve the response speed of the load torque observer.Compared with the traditional adaptive backstepping control algorithm,the novel adaptive backstepping control strategy has significant advantages in load disturbance attenuation performance and response time of load torque observer.Thirdly,based on the backstepping control strategy,the speed loop and flux loop are designed by the active disturbance rejection method,and the active disturbance rejection backstepping control algorithm is formed.The extended state observer compensates the disturbance to the speed controller and improves the load disturbance attenuation performance of the system.The inner current loop is designed by backstepping method to improve the response time of the system.The effectiveness of the scheme is verified by simulation.Fourthly,establish the equivalent circuit of the induction motor in the steady state,analyze the relationship between the motor loss and the rotor flux,and find the optimal rotor flux with the lowest loss.When the motor is running in steady state,the rated rotor flux will be smoothly switched to the optimal rotor flux to achieve efficiency optimal control.However,it is difficult to know the time when the motor changes from steady state to dynamic state,so it is difficult to grasp the switching time of rotor flux.The Gauss smooth switching function based on the speed error is applied to the rotor flux coordination control of induction motor to solve the problem that the time point of the rotor flux switching in the efficiency optimization control is difficult to know accurately.Fifthly,based on the induction motor platform of LINKS-RT experimental system,the proposed scheme is verified by experiments.The novel adaptive backstepping control algorithm is compared with the traditional adaptive backstepping control,and the experimental verification and analysis are carried out in the aspects of speed response time,convergence speed of load torque observer and load disturbance attenuation performance.The experimental platform verified the practicability of the rotor flux optimization control algorithm.To sum up,in order to solve the unknown load disturbance in the speed control system of induction motor,this paper uses backstepping and active disturbance rejection control algorithm to estimate the load torque change accurately in real-time and improve the load disturbance attenuation performance of the system.The coordination control algorithm of rotor flux based on speed error solves the problem that the time point of rotor flux switching is difficult to grasp,and realizes the efficiency optimization control of induction motor,which has a good application prospect.