Research On Switched Reluctance Motor Control System Based On Fractional Sliding Mode

Switched Reluctance Motor(SRM)has advantages of low cost,high efficiency,wide speed range and strong control flexibility,so its application in the field of industrialcontrol has been continuously promoted in recent years.For example,SRM is used as the vehicle-well test and production test lift equipment's drive system to save energy,which not only simplifies the system structure and reduces energy loss of transmission,but also improves its reliability and economic.However,the SRM has a high degree of nonlinearity,strong coupling and large torque ripple because of the double-salient structure.Thus,the applications of SRM are greatly limited.Due to the salient pole structure and nonlinear characteristics of SRM,it is accompani-ed by torque ripple during normal operation,which caused mechanical damage and energy loss to oil production test equipment.Therefore,the strategy of Direct Instantanous Torque Control(DITC)based fractional sliding mode wasedresearched to reduce the torque ripple and improve the speed control accuracy of SRM.Firstly,the structure and operation principle were studied.The finite element analysis is used to obtain the data of L-I-?,Te-I-?.Then,SRM control system simulation model is built in Matlab/Simulink,which analyzed by PID current chopping control strategy to verified the reliability of the model.Through simulation of SRD,it is found that its torque ripple is large.For torque ripple,DITC based Torque Sharing Functions(TSF)method was studied.Baesd on the minimum RMS of phase current and torque ripple rate,the influence of TSF and different current overlap angles on the torque ripple is analyzed.By selecting the best control parameters,the system efficiency is improved and the torque ripple of SRM is suppressed.In order to achieve the nonlinear control of SRM,a Sliding Mode Control(SMC)based Fractional Order Control(FOC)is used for SRM speed controller.SMC-FOC has extended the conventional sliding mode surface from integer order to fractional order.The equal velocity of fractional differential is introduced in SMC-FOC design process.The controller of SMC-FOC uses the characteristics of fractional-order slow transfer of energy to improve the dynamic performance of SRM,suppress the shaking of the sliding surface,and further reduce the torque ripple rate.Secondly,the hardware and software design of SRD is carried out base STM32 core.Finally,the overall scheme of energy-saving of the vehicle-well test and production test lift equipment with hydraulic balance was designed.The trapezoidal speed planning was carried out for the operating characteristics of the rod pump.SMC-FOC strategy was applied to oil production test equipment can obtain excellent dynamic and static characteristics based Simulink platform.At the same time,the progress of the overall plan for energy-saving renovation was summarized.