A Comparative Performance Study of an Interleaved Boost Converter Using Commercial Si and SiC Diodes for PV Applications

A performance comparison of an interleaved boost converter (IBC) using Si and SiC diodes for photovoltaic (PV) energy conversion systems is presented in this paper. The performance attributes under investigation include the semiconductor device behavior, thermal requirement, system efficiency, and power density. The IBC is designed to sustain the dc-link voltage in the energy conversion system and to provide the maximum power point tracking in the PV system. Due to the absence of reverse recovery current in SiC Schottky diodes, low switching losses are generated in diodes and switches. This benefit results in a higher system efficiency and smaller cooling system design requirement. As a benefit, the volume and weight of the heatsink can be further reduced. Furthermore, behaviors of the power semiconductors, which will impact the performance in the system, are discussed in the paper. The validity of the analysis is confirmed experimentally with a 2.5-kW IBC prototype with relatively wide power and input voltage operating range. The overall performance of the IBC prototype using Si and SiC diodes is summarized in a table for easy comparison.