Research On The Rotor Position Indirect Detection Control System Of Switched Reluctance Motor

Switched reluctance motor(SRM)benefits from a relatively simple and rugged structure,mainly used in the field of mine and aviation etc.At present,the most successful application of SRM is the electric screw press,which fully exerts the advantages of SRM overload capacity,frequent positive inversion,wide speed range and energy saving.Electric vehicles are becoming the mainstream of development because of the country's vigorous implementation of clean energy and the tightening of the traditional energy policy.Meanwhile,because of the superior performance and great potential of development of SRM,it has become a hot spot in the research of electric vehicles and hybrid electric vehicles.Since SRM needs rotor information to run normally,the position sensor is used to detect rotor commutation position in SRM to provide commutation information for power converter.However,the current application of the physical sensor increases the complexity of the motor structure and reduces the reliability of the operation of the drive system,which makes the method of determining the rotor position by using some electrical characteristics of the SRM becomes the focus of academic research.In this paper,this area has been studied in depth.Based on the analysis of SRM's own operating characteristics and theoretical derivation,two different position detection schemes are applied to SRM running at different rotational speeds.Under the conditions of motor startup and low-speed operation,this paper uses the combination of pulse excitation and inductance model to determine rotor position,which can ensure the accurate position estimation.However,this method will increase the error in the process of motor speed increase.Therefore,under the conditions of medium-speed and high-speed operation,this paper improves on the simplification of the flux linkage method and the model analysis method.Based on the function analysis method,the analytical model of the flux linkage fitting function is established.The analytical model uses the piecewise function to describe the flux linkage,which realizes the single-valued mapping relationship between position angle and flux linkage.Since the model is a linear function of the rotor position angle,the model can be easily solved in the reverse direction and the rotor position information can be obtained directly to achieve continuous estimation of the rotor position.For mentioned herein theory,to build a simulation model of the system and the motor position sensorless control system experimental platform.Through the simulation and experimental comparison under the same condition,it can be proved that the scheme can estimate the rotor position of SRM well,and start the motor ensure the stable operation within the rated range of the motor.