The operation of power MOSFET devices at cryogenic temperatureshas been shown to offer potential advantages in large conversionsystems, due primarily to a major drop in on-resistance. This paperinvestigates the use of high frequency switch mode power electronicsconverters based on available commercial devices operating at cryogenictemperatures, particularly in relation to electricity supplyapplications. Efficiency, transient response and power density are allimportant characteristics which show potential improvement over state ofthe art room temperature implementations. These characteristics arediscussed in relation to both simulation and experimental measurementsof a half bridge inverter configuration, and the initial results fromtests on an experimental 50 kW three phase inverter are reported. Acomparison is made between the circuit performance predicted usingstandard power electronics simulation tools, applied to modellingswitching characteristics at 77 K, and results derived from measuredvalues. The simulations show general full cycle waveform agreement withthe experimental model, but there is considerable discrepancy whenfocusing on the switch transitions. This can result in an inaccurateestimate of overall converter switching power loss which must beaccurately defined, since it is the dominant loss mechanism at cryogenictemperatures. Application areas where cryogenic power electronicconverter systems may be used in the future are identified, and where,in combination with high temperature superconductor (HTS) power systemsequipment, synergistic benefits may result
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