VSI-PWM RECTIFIER INVERTER SYSTEM WITH A REDUCED SWITCH COUNT/

A current-controlled VSI-PWM rectifier and inverter with capacitor de link is regarded as one of the most important structures for three-pha se to three-phase power conversion, This type of converter normally re quires twelve switches for a rectifier and inverter composed of self t urnoff switch such as a bipolar transistor or an IGBT with an anti-par allel diode, In this paper, a new three-phase to three-phase converter for ac motor drives is proposed, The proposed converter employs only eight switches and has the capability of delivering sinusoidal input c urrents with unity power factor and bidirectional power flow, This pap er describes the feasibility and the operational limitations of the pr oposed structure, A mathematical model of the system is derived using the generalized modulation theory and experimental results for steady state and dynamic behavior are presented to verify the developed model .