A hybrid control strategy of hybrid-excitation switched reluctance motor for torque ripple reduction and constant power extension

A novel hybrid control strategy combining vector control and current continuous conduction is proposed in this paper to improve the performance of a hybrid-excitation switched reluctance motor (HESRM). Vector control, widely used in ac machines, is redefined in HESRM based on static torque characteristic to simplify an HESRM controller and reduce torque ripple. However, at a high-speed and heavy-load operation, current tracking accuracy deteriorates and torque ripple reduction effect gets worse. Current continuous conduction is combined with vector control to improve current tracking accuracy and maintain smooth torque ripple. In the HESRM, the power generally falls nearly in proportion to the square of speed over based speed, and a traditional control technique can maintain only a narrow constant power range. This novel vector control is easy to achieve phase advance and current continuous conduction simultaneously. By combining these two together, the HESRM can extend the constant power in a wider speed range and efficiency is also improved. Simulations and experiments in different conditions are carried out to verify the effectiveness of a hybrid control strategy.