Research On Torque Ripple Reduction And Speed Control System For Switched Reluctance Motor

Switched Reluctance Motor(SRM)has the advantages of low production cost,strong fault tolerance,great drive efficiency,and wide speed range.It is applicable in high velocity and rough environment,and it has a broad development in various fields such as aerospace industry,traction transportation,electric vehicles,oilfield coal machinery,textile machinery and so on.However,on the one hand,it has problems such as high noise and torque ripple during operation due to the SRM’s own magnetic circuit nonlinearity and pulsed phase current operation.On the other hand,the PI control selected for speed control is not robust enough to meet higher control requirements when disturbed,which affects the overall system performance.Based on the above problems,the torque pulsation suppression and speed control method are studied in this paper,and the main research works can be summarized as follows.Firstly,a torque sharing function based on torque compensation in segments is studied for the problem that the actual output torque has poor torque tracking effect.The area between opening angle and closing angle is segmented,and the error between the actual torque and the reference torque is compensated to the adjacent phase to improve the torque tracking effect.The simulation results show that the proposed torque control method can effectively suppress torque ripple.Secondly,a current prediction control method based on an extended sate observer is investigated for the phenomenon that the actual current output under the dead-beat current prediction control does not track well on the reference value during operation,and is prone to current jitter.The method corrects the predicted current by using the current observations of the system during actual operation,and then compensates the voltage by applying the system disturbance to improve the tracking effect of the current controller,and verifies the effectiveness of the studied method by comparing it with the dead-beat current control in simulation.Thirdly,the method of PI control in speed control system is difficult to meet speed control requirements in complex situations.Based on the existing SRM speed control,an optimized structure of active disturbance rejection speed controller is studied in combination with active disturbance rejection control theory.Compared with the traditional control method,the simulation results show that the control method can improve the robustness of SRM speed control system.In order to verify the effectiveness of the studied method,a experimental platform based on the switched reluctance motor control system is used for experimental verification.The experimental results show that the torque ripple suppression and speed control method studied in this paper can effectively improve the actual operation performance of SRM,and provide an engineering method for SRM torque ripple suppression and speed control optimization.