Low torque ripple control of current-fed switched reluctance motors

The paper addresses a basic control issue in switched reluctance motor (SRM) drives-the production of ripple-free torque. Simple and largely model-independent conventional switching patterns are not able to satisfy this requirement. Our goal is to improve SRM dynamical performance by compensating for motor nonlinearities while maintaining the robustness of conventional methods in a simple position and current feedback. Our method is based on a complete parametrization of position dependent voltage and current profiles in ripple free operation and waveform optimization to minimize power supply requirements. We allow for model uncertainties and show that our strategy consistently outperforms the conventional policy. Experimental data verifying the analytical approach are included, and implications for self-tuning and shaft sensorless operation are outlined.