Development of a compact 60kW three-phase asymmetry half-bridge power convertor with specifically designed busbar for switched reluctance machines

Abstract

This paper presents a power convertor design of a 60kW three-phase asymmetry half-bridge power convertor for switched reluctance machines (SRM). With established topology, voltage overshoot is sufficiently analyzed theoretically. To minimize voltage overshoot, this paper optimized the structure of main circuits, snubber capacitors and drive circuits. When dealing with main circuits structure, a low inductance busbar design with optimal capacitors arrangement is proposed for stray inductance minimization. For drive circuits, active clamp circuits are adopted to limit current reduction. Take minimized stray inductance and active clamped circuits into consideration, mathematic model between snubber capacitors and voltage overshoot is proposed for optimization. In the end, feasibility and improved performance are demonstrated with simulation and experiments.