Research On SRM Direct Instantaneous Torque Control System Based On TSF

Switched Reluctance Motor(SRM)has the advantages of simple structure,high mechanical strength and independent operation of the windings,and have excellent starting current,starting torque and fault-tolerant operation.It has been widely concerned in recent years,and is gradually applied to electric vehicles,industrial automation,aerospace equipment and other market areas,especially domestic new energy electric vehicles to promote the application of SRM for the broad prospect.However,due to its stator and rotor double salient pole structure and non-linear electromagnetic torque characteristics,the torque ripple is large and the noise is large,which limits its application in the occasions of high noise and torque ripple.In order to reduce the torque ripple and improve the overall efficiency of the system,a direct instantaneous torque control strategy based on torque distribution function(TSF)is proposed in this paper.Firstly,the characteristics of SRM are introduced,the existing problems and the research status of torque pulsation optimization are expounded,and its basic working principle and mathematical equation are analyzed.Based on the comprehensive analysis and modeling method,the off-line stall flux measurement and torque measurement modeling method are given.Then,the nonlinear and mathematical modeling of SRM is carried out according to the torque and flux linkage table obtained by measuring the prototype.Secondly,the three basic control methods of SRM,the operating characteristics of the motor and the theoretical analysis of the TSF of the cosine type are presented.The problem of the torque collapse in the commutation area is analyzed theoretically.Based on this,a direct instantaneous torque control method based on the TSF is proposed.The system simulation diagram is built under the Matlab/Simulink environment,and the torque ripple and current waveform under current chopping control strategy are compared and analyzed.The correctness of the instantaneous torque control strategy based on the TSF is verified.In the end,this paper designed the power converter,control circuit,drive circuit,current detection circuit and position detection circuit of SRM drive system,and built a 15KW three-phase 12/8-pole SRM control system experimental test platform,The flow of the software design is given,and the key program of the system is designed in detail.Then the speed control and load testing of the whole control system are carried out.Then the control algorithm proposed in this paper is verified experimentally.The results show that the direct instantaneous torque control strategy based on the TSF is effective and feasible for the optimization of torque ripple and improving the operating efficiency of the system.