SiC‐based high‐gain DC–DC converters with fault ride‐through capability

Abstract

This study presents active switched passive network-based high-gain DC–DC converters. The active switched network is formulated using two inductors, one capacitor and two diodes. Hence, the network is named as a 2L–C–2D network. Using ten components, an asymmetric high-gain DC-DC converter is proposed. This converter achieves a gain of 29 at an 80% duty ratio. In the asymmetric converter structure by replacing the inductor by another 2L–C–2D network, the symmetric converter structure is proposed using 14 components. This converter structure achieves the gain of 49 at the same 80% duty ratio. Apart from increasing the voltage gain, the 2L–C–2D network helps to reduce the voltage and current stresses of the converter. The utilisation of two semiconductor switches in the proposed converter structures permits a fault ride-through capability even when any one of the switches fails. Operations of the converters in continuous conduction mode (CCM) and discontinuous conduction mode (DCM) are discussed, and the boundary condition between CCM and DCM is derived. To limit the effect of parasitic elements on the converter performance, SiC-based semiconductor devices are used in the 500 W hardware prototype. The maximum efficiency of 92.8% is achieved in the case of a symmetric converter.