Evaluation of Phase-Commutated Converters for Slip-Power Control in Induction Drives

Three different phase-commutation thyristor bridges are applied to slip-power control of an induction motor. The performance of the drive is experimentally evaluated for each thyristor bridge with respect to input power factor, efficiency, total. input current, size of the dc-link inductor, and regulation. The best results are obtained with the eight-thyristor bridge while the conventional six-thyristor converter offers the worst overall performance.