Comparison of bi-directional switch components for direct AC-AC converters

The objective of this paper is to assess the performance of bi-directional switch components for direct AC-AC (matrix) converter applications. Three 2-phase to 1-phase matrix converters will be constructed, each with different bidirectional switch components. The three bi-directional switch structures to be considered are: silicon (Si) diode-Si IGBT, silicon carbide (SiC) diode-Si IGBT and Si reverse blocking IGBT (RB-IGBT). All of the commutation scenarios possible in a matrix converter topology using two or four-step commutation are studied. The improved reverse recovery performance of the SiC Schottky diodes is assessed with reference to measured switching waveforms. The affect of the three different switch structures on the overall performance of the matrix converter with particular attention to power circuit losses is investigated.