A high-performance switched reluctance motor drive

In spite of all the advances in switched reluctance motor, the evolution of the motor drive has not reached the stage where it can be feasible for high performance applications. High torque ripple during phase commutation, need for a good modeling indirect position sensing and optimum converters issues of interest for the research in SRM drives. The performance of SRM drive can be improved by better motor design, efficient converter and an optimum control. This research has focused on the development of a high performance drive through improved converter and controller designs.; Two novel SRM converter topologies for high and low voltage applications, modified from the conventional C-dump converter, have been developed during the course of this research. The new converter topologies eliminate most of the disadvantages of the C-dump converter without sacrificing its attractive features. The attractive features of the proposed converters are: lower number of power devices, full regenerative capability, freewheeling in chopping or PWM mode, simple control strategy and faster demagnetization during commutation. Both energy efficient converters I and II have been simulated and tested experimentally.; In order to achieve a ripple free torque control reliable information of the actual torque of the motor is very important, which requires an accurate nonlinear dynamic motor model. A nonlinear switched reluctance motor (SRM) model with on-line parameter estimation scheme using recursive identification has been developed during this research. The model is robust towards any disturbances or parameter variations in the motor. The parameters of the model are also adjusted to account for any errors in rotor position, which means crude inexpensive position sensors can be used. Once a good estimation of torque was achieved, the next task was to devise a good control algorithm that can provide a ripple-free torque response without high current peaks. An adaptive fuzzy control scheme has been developed. The fuzzy parameters of the controller are chosen randomly and the controller adjusts these parameters to give the optimum control. The controller is able to produce smooth torque up to the motor base speed and is robust towards errors in rotor position information.; The on-line torque estimator and adaptive fuzzy control schemes have been simulated using a 1.2 HP SRM model. Simulation results of the torque estimator provides an accurate estimation of the torque in spite of errors in rotor position. The results from the fuzzy controller show an optimum control reducing the torque ripple to a minimum up to the base speed of the motor.; Experimental implementation of the high performance SRM drive was carried out to verify the performance. The controller was implemented with a Tiger-30 evaluation board that used TMS320C30 DSP. The experimental results show that each newly developed component of high performance drive improve the performance of the drive providing a low torque ripple up to the base speed of the motor.