1kW 10V to 400V converter for a solid oxide fuel cell

Abstract

A new industry solid oxide fuel cell outputs 10V instead of 25V at 5kW, the power level intended for residential use. A 5kW 10V to 400V converter is designed using a simple cost-efficiency optimized approach. Power loss is modeled based on ideal waveforms allowing independent optimization for each component. Four topologies are analysed at a switching frequency of 20kHz and $0.9CDN per Watt: the voltage-fed H-bridge and push-pull prove to have a much lower cost function than their current-fed forms. A 1kW voltage-fed H-bridge prototype is built, working up to 417W output with 86.3% efficiency and 292V output. Projections to the desired 1kW load indicate the converter would output 350V with 89% efficiency. A conservative estimate for the cost of the high volume production of the prototype was sim;$153 USD. The estimate for the high-volume production of the 5kW unit was sim;$115 USD/kW.