SPEED CONTROL OF SWITCHED RELUCTANCE MOTORS

Abstract

A speed control systern for a switched reluctance motor ( SRM ) drive using proportional-integral control strategy is designed and presenred in this t hesis. Performance is based on the ability to provide each phase with pulses of current during the torque productive pends ( the zone of increasuig inductance ) by selecting precietermined switching angles. The control system maintains the desired speed in the face of variations of the load or the rnotor parameters. Variable speed can be achieved using this control system. After reviewing the operating principles of the SRM and its different control strategics, modeling has ken done under the assurnption of linear magnetic characteristics. The torque characteristics and the dymmic differen tial equa tions. nevertheless. are nonhear. The control structure consists of a fdforward controuer and a propoflional-integral speed controller. A hysteresis controller is also employed t~ maintain the current within a pre-set band based on a defmed algorithm. Stability of the nonlinear control system has been investigated using the second method of Lyapunov and the method of Krasovski In this thesis, two control schemes; narnely current-source switched reluctance motor ( CSSRM ) and voltage-source switched reluctance motor ( VSSRM ) are designed, analyzed, and simulated under different working conditions using the Matiab software package to investigate the steady-state operation and dynamic response of the system. The rnotor performance and simulation results are discussed. . .