A Low Cost Three Phase Induction Motor Drive for Single Phase Fed Industries

This paper presents a cost effective 3 phase induction motor drive system operated using a single-phase supply. A three-phase voltage source inverter is given a DC voltage by rectifying the single-phase supply. This inverter is connected to the induction motor and the switching frequency given to the inverter can be used to change the applied frequency to the motor and thereby the speed. 180-degree conduction method is used to operate the inverter. Switching signals required for the MOSFETs of the inverter are supplied by an ATmega32SP microcontroller through an isolated MOSFET driver circuit. Separate power supplies have been used to power-up the receiving end of the driver circuit. Experimental results on a 0.375 kW,400V, 4 pole star connected 3 phase motor suggested that the drive system can effectively contro13 phase induction motors preserving low implementation cost with simple control.