Experimental Study of a Three-Phase Diode Rectifier Operating at Cryogenic Temperature

We investigate here the feasibility of operating a three-phase diode rectifier at cryogenic temperature. To do so, several power diodes are tested at room and LN2 temperatures. Then a 3.4 kW three-phase diode rectifier prototype is built and tested at room and LN2 temperatures. Besides we prove that one can predict the performances of such cryogenic diode rectifier by using only the measured diode I-V characteristics. Finally, we assess the relevance of this technology by comparing a cryogenic diode rectifier with its conventional counterpart. The gain may not be in terms of efficiency if cooling power has to be generated, but in terms of power density, since the heat sink is greatly reduced when considering LN2 operation. This study is of interest for compact and lightweight superconducting conversion chains in various sectors, including wind energy and air transportation.