Condensed Buck-Boost Switched Capacitor Converter for Efficient Voltage Distribution in Electrified Aircraft

Abstract

Switched capacitor converters are a category of power electronic converters that harness the significantly improved energy density of capacitors as opposed to that of their conventional, inductor-based counterparts to reap benefits in terms of efficiency, size, and utilization. This work presents the analysis, design, construction, and evaluation of one such converter, inspired by the flying capacitor multilevel topology and referred to as a condensed buck-boost converter. This converter is designed and built for an application as the interface between the battery voltage and DC bus on partially electrified aircraft, where the advantages of its ability to step up/down voltage in an efficient and lightweight fashion can be fully realized. In order to be implemented in hardware for the first time, this work utilize new monolithic, bidirectional GaN FETs, whose reverse voltage blocking capabilities open new possibilities for a converter design that wastes less power and occupies less board area. This converter is compared with others that perform similar functions to showcase the benefits that this topology has to offer.