Abstract:Switched reluctance motor speed control system is a complex nonlinear time-varying system, with large load disturbances and severe coupling between variables. A method of using a linear auto disturbance rejection control strategy to control the system is proposed for the performance characteristics of the above systems. Firstly, in order to overcome the changes of load disturbances, the Nonlinear characteristics of motor flux linkage and the coupling of internal and external disturbances such as current and position parameters, an extended state observer is designed to accurately estimate the system internal disturbance and external disturbance and compensate in real time. Then A PD (proportional-derivative) controller is designed to suppress the tracking error between the system observer and the observation object state variable fed back by the extended state observer. Finally, the designed control system is tested on the simulation platform and compared with the traditional PID control scheme. The results show that the linear active disturbance rejection controller for a given step signal only needs 0.09s to reach steady state without overshoot, while PID control needs 3s to achieve stable tracking. Therefore, compared with the traditional PID control, the linear active disturbance rejection controller has better dynamic and static performance, and the system also has good control effect in the case of external load disturbance and internal model parameters change, showing a very good robustness.
