Research on a Novel Capacitor Clamped Multilevel Matrix Converter

Abstract

A new multilevel matrix converter that can be applied to medium or high voltage ac drives is presented to alleviate harmonic components in the output voltage. The proposed converter contains six flying capacitors to balance the voltage distribution of series connection bidirectional switch modules and provide middle voltage levels. Stable flying capacitors voltage must be maintained to facilitate the operation of the converter. When the converter is working, the voltage of flying capacitors can be controlled by swapping two switching modes with opposite charging current corresponding to each middle voltage levels. A simple output voltage vector synthesis method is described and utilized. The operation and commutation strategies are discussed. Simulations and experiments are carried out to validate the proposed converter. Comparisons are made between proposed converter and conventional matrix converter.