A modified split-supply switched-reluctance drive inverter

This paper describes the application of a new simple voltage-boosting feature to a split-supply SR (switched-reluctance) motor inverter. As its name implies, the SR motor always operates in switching mode and has distinct motoring and generating rotor angular regions. The effectiveness of the energy conversion process of the SR motor depends basically on the ability of its inverter to inject adequate current during the positive-torque angular region and to reduce the current to a negligible value during the negative-torque angular region. The modified inverter effectively generates boost voltages for accelerating current build-up and decay and hence enhances the performance of SR motor drives. Benefits of the added boosting include: higher average current; better energy recovery during commutation; and a wider feasible speed range. This paper assesses the implications of the boost feature on inverter cost and performance. A time-stepping simulation procedure which includes the modelling of current overlapping between phases is presented together with simulation results.