Preliminary Experiments of a Cryogenic Boost Chopper Based on Low-Resistance MOSFETs and Zero-Resistance ReBCO Inductor under 77K

This paper presents the preliminary experiments of a cryogenic boost chopper based on low-resistance MOSFETs and zero-resistance ReBCO inductor under 77K. Three cryogenic operating behaviors of on-state resistances and breakdown voltages of commercial MOSFETs and on-state voltage across their built-in reverse diodes are experimentally investigated to demonstrate the technical feasibility of cryogenic power conversion. Being verified by extremely low conducting resistances under 77 K, two cryogenic power MOSFETs and one ReBCO inductor are subsequently used to develop a cryogenic boost chopper circuit. The experimental results obtained by different circuit schemes and testing conditions show that the overall power conversion efficiency in the cryogenic boost chopper is improved by about 7% than that in conventional boost chopper. These preliminary experiments lay some technical bases for maximizing the operating efficiencies in superconductor-semiconductor-coupled cryogenic power electronic interface towards smart DC microgrids.