A SCR-based switch-control strategy of delta/wye switchover for delta connected induction motors

A new approach is presented to decrease the surge current in the process of delta/wye switching to realize the purpose of energy saving for delta connected induction motor drives in this paper. A delta/wye switchover energy-saver is developed which hardware is based on the SCRs and DSP. Software program is designed to control the triggering sequence of SCRs, within several cycles until the switchover is completed. The surge current can be reduced significantly when switching from wye to delta and even be eliminated completely from delta to wye. Experimental results prove this strategy is appropriate for the delta/wye switch energy-saver for delta connected induction motors.