Resonant switched reluctance motor drive and its power conditioning with switched-capacitor techniques

Abstract

In the past, switched-capacitor DC-DC converters were mainly used on low power applications for doubling voltage or invert voltage. They are not suitable for high power applications because of their current stress problem and low efficiency. In this project, families of switched-capacitor DC-DC resonant converters are developed. Current stress problems have been solved in the circuits so that they can work under high power operation. All transistors in the circuits are switched under zero-current switching condition to improve the efficiency. Since the improvements are done, the switched-capacitor techniques can be used for power conditioning for applications such as motor drives. Implementation of high power switched-capacitor resonant converter is done. Switched reluctance motor (SRM) has the advantages of high power density, fast response and robust. To drive a SRM, electronic circuit is need. A newly designed switched reluctance motor drive is introduced in the thesis. Active-clamp resonant technique is applied in the motor drive to provide soft-switching for all high switching frequency transistors. Performances of both electromagnetic interference (EMI) and efficiency of the motor drive are improved. Performance of Switched reluctance motor is usually poor when its speed is high because of its long regenerating stage. A method by using switched-capacitor based power conditioning is proposed in the thesis. Waveforms of the commutating current of the SRM are modified by a switched-capacitor front-end converter. In the whole system, all high frequency transistors are switched under zero-voltage switching condition. Mathematical Analysis, Computer simulation, and experiments have been done for all proposed circuits. Description and explanation of the results are provided in the thesis.