Single-phase input reduced switch count AC-AC drive systems

This paper proposes AC-AC reduced switch count drive configurations to be used with single-phase grid. The configurations are used for single-phase to three-phase drive applications and have three legs. A control strategy is proposed to obtain the maximum voltage rating of the converters. The system can be used for applications in which the motor operates with constant frequency at high speed and variable frequency at low speed. The principle proposed is extended to derive configurations for single-phase to single-phase drive applications. Experimental and simulated results are presented.