MODELLING AND SIMULATION OF DIRECT TORQUE CONTROL FOR MULTI-PHASE SWITCHED RELUCTANCE MOTOR DRIVE

摘要

Switched reluctance motors (SRMs) are rugged, simple in construction and economical compared with synchronous motor and induction motor. They are known to have high-peak torque-to-inertia ratio and the rotor mechanical structure is well suited for high-speed applications. Direct torque control (DTC) is known to produce quick and robust response in AC drives. However, during steady state notable torque, flux and current pulsations occur. They are reflected in speed estimation, speed response and also in increased acoustic noise. This paper presents a novel DTC scheme where fast torque response with low ripples in the stator flux and torque of five-phase SRM drive can be achieved. In comparison with DTC of three-phase, the five-phase DTC system has more space vectors providing greater flexibility in selecting the inverter switching states, thus accomplishing a more precise control of the stator flux and torque. Simulation results clearly demonstrate that the combination of DTC with multi-phase SRM realizes higher performance with greater prospects in industries.