Control Method For Single-Winding Bearingless Switched Reluctance Motors With Wider Rotor Teeth

The bearingless switched reluctance motors(BSRM)have abundant potentials in the high-speed motor filed for their simple structure,reliable performance and removing the mechanical bearings.These characteristics have arisen much attention from the researchers.However,the coupling of torque and levitation force in bearingless switched reluctance motor tends to make the machine's control complex.So,the bearingless switched reluctance motor is proposed,which can eliminate the coupling of torque and levitation force.The decoupling feature will promote its application in industries.The single-winding bearingless switched reluctance motor is chosen as the research subject in this paper to analyze the machine's control methods in speed-regulating and generation areas for the performance requirements of starter/generator integrated device.Furthermore,the control platform is designed in this paper to provide further support for the following research.First,this paper compares the structures of two different bearing switched reluctance motors by finite element analysis software and explains the decoupling mechanism of torque and levitation force in the single-winding bearingless switched reluctance motor with wider rotor teeth.Then the mathematical models of toque and levitation force are both derived based on the Maxwell tensor method.Second,the relationship between average toque and square-wave current is formulated.In addition,the number of control variables is reduced by introducing three new variables,which can improve the mathematical model of levitation force.Based on these studies,the simulation models of single-winding bearingless switched reluctance motor is created in the Matlab/Simulink environment to investigate the performance when average torque and instantaneous levitation force are selected as the control objectives.Third,this paper studies the generation mode of single-winding bearingless switched reluctance motor with wider rotor teeth.The expression for calculating the turn-on angle of suspension currents is derived.The control method of regulating the load voltage is also proposed.Then the open-and closed-loop generator simulation models are created in Matlab/Simulink.This paper further explains the electromechanical energy conversion by analyzing the current-linkage state of coils.Finally,the hardware platform is designed,which mainly consists of the master controller,current sampling and regulating circuit,power converter and its driver,protection circuit and some other associated circuits,which will provide robust support for the following work.