Techno-economical comparison between Si and SiC switches in a VIENNA rectifier

Power electronic converters are non-linear loads from the grids point of view, making power factor correction (PFC) an integral part of any mains-fed converter. VIENNA rectifier is a three-phase active PFC rectifier topology, which consists of a diode bridge accompanied by a neutral point connection via reverse-blocking switches. The factors affecting the optimal switch choice include the used switching frequency, maximum allowed input current total harmonic distortion, and initial investment cost. In this paper, the suitability of Si IGBTs and SiC MOSFETs in a VIENNA rectifier is evaluated with a technical and economical comparison. The findings indicate that for a 15 kW VIENNA rectifier with a 5 % THD specification, Si IGBTs are a more cost-effective alternative than SiC MOSFETs. This is mainly due to the high initial investment cost of SiC MOSFETS, and no distinct technical advantage in using over 30 kHz switching frequencies.