Controllability of radial displacement in bearingless switched reluctance motor using bridge configured winding

Abstract

Due to the salient features of stator and rotor in Switched Reluctance Motor the air-gap of the machine does not remain uniform during its motoring operation. This innate characteristic is responsible in producing considerable amount of radial force in the motor. However, on the other hand eccentricity or radial displacement of the rotor is another key cause to this production of radial force. In this paper a single winding structure called bridged configured winding in a 12/8 BSRM is delineated which can be used to deploy the radial displacement by injecting controlled current within the same winding. Initially a mathematical model of the motor is developed and verified using finite element modeling. The developed model is analyzed by integrating a voltage source asymmetric converter for motoring operation and separate asymmetric converters for injecting currents into the winding to control the radial displacement of the motor. Investigations of radial forces at various rotational positions and controllability of radial displacement are carried out using a simple PID controller system.