Research On Suppression Of Torque Ripple For Doubly Salient Electro-magnetic Motor

Doubly salient electro-magnetic motor is a kind of DC motor with high reliability.The rotor of doubly salient electro-magnetic motor has no winding and permanent magnet,which has the advantages of simple tructure,high power density,wide speed-regulating scope,low manufacturing cost,good fault tolerance,and suitable for high temperature,high speed conditions.Because of these advantages,doubly salient electro-magnetic motor has a good application prospect.However,due to its serious torque ripple,the application in high precision or noise sensitive occasions is limited.At present,there have been some research results on the commutation torque ripple reduction strategy of doubly salient electro-magnetic motor,but few researches have been carried out on the non-commutation torque ripple reduction method.Both commutation and non-commutation torque ripple will cause vibration,noise and speed fluctuation.Therefore,it is of great significance to study the torque ripple suppression strategy of doubly salient electro-magnetic motor.This paper retrospects the developing process of doubly salient electro-magnetic machine and the research status of torque ripple reduction method from the start.Then,based on the mathematical model and working principle of doubly salient electro-magnetic motor,this paper analyzes the cause of torque ripple in detail.In view of the non-commutation torque ripple caused by the back EMF distortion,a control method for controlling the average input power of the motor is proposed.At the same time,the proposed control method is combined with the advance angle control strategy to suppress the commutation torque ripple,and the current and torque characteristics of doubly salient electro-magnetic motor commutation are studied.Finally,based on MATLAB,the simulation model of doubly salient electro-magnetic system based on average input power control is set up.The results of simulation prove the correctness of the theoretical analysis and the effectiveness of the average input power control.At the same time,the hardware platform is built,and the motor-driven program is designed,and the proposed method is verified by experiments.The experimental results show that the method proposed in this paper can effectively eliminate the commutation torque ripple of doubly salient electro-magnetic motor,and can solve the problem of difficult selection of advance angle in advance angle control at same time.