SPrasad N. Enjeti, Sewan Choi, “An Approach to Realize Higher Power PWM AC Controller”
Abstract : AC controllers are widely used in industry in many applications. Recent research has shown that PWM operation of ac controllers offers high performance characteristics. However, PWM con- trolled ac controllers are plagued with difficulties to commutate inductive,load current from one hi-directional switch to another
due to finite switch on/off times. This paper proposes a four step
switching strategy for repeated on/off operation of bi-directional
switches in an ac controller. The proposed approach permits safe
transition of inductive load current at all power factors from one bi-directional switch to another even in the presence of source side stray inductance. Results from an experimental proto-type
ac controller coupled to an inductive load are also discussed.