Comparison among electronic start up methods for induction motors

This paper presents a useful comparison of performances during the start up of the induction machine by means of electronics starters. To feed the induction machine, two chosen circuits configurations utilize back-to-back connected series thyristor and 3-phase inverter. Some control strategies such as discrete frequency control, soft starter and field oriented control have been proposed to reduce current and improve torque. Simulation results, obtained from 4kw induction machine with these electronic methods, show an improvement of the performances in the starting period by reducing the current and increasing the torque first by using 3-phase inverter then by discrete frequency control (DFC) and finally with soft starter.