A high efficiency converter for switched reluctance motor (SRM) drive is developed in this paper. In the proposed converter, the power semiconductor device with shorter switching time is employed to implement its high-speed PWM switches. And the soft-switching control is employed for further reducing their switching losses. To achieve this, an auxiliary resonant circuit is added to the PWM switch, and its zero-voltage-transition (ZVT) soft switching is obtained by applying suitable switching signals to the main and auxiliary switches. No extra voltage and/or current sensors are required. Having derived the governing circuit equations, a design procedure is proposed to systematically find the constituted components of the auxiliary branch. As to the low-speed commutation switches, they are realized using the power device having low on-state voltage. Owing to the ability of making PWM switching control, the SRM motor drive with the proposed converter possesses good driving performance. The performance of the designed converter is demonstrated by some simulation and experimental results. An approach for measuring the energy conversion efficiency of a SRM drive is also proposed. (17 refs)
