The basic idea of this system is to generate three phase six triggering pulse with isolation using ARM-7 controller. In the absence of any one phase three phase preventer circuit protects the induction motor from single phasing, along with this automatic phase selector circuit selects present phase consider as single phase with neutral when one of the phase is missing from three phase supply in sequence of RYB. Power circuit converts single phase 230 V AC to DC 350 V. and an inverter circuit converts three phase AC 350 V which drives the induction motor. The circuit is designed to generate the three-phase variable frequency supply required to control the speed of induction motor in the various industrial application.