LARGE CURRENT AND LOW-VOLTAGE SWITCHING DEVICES USING HTS THIN-FILM

A high Temperature Superconducting (HTS) thin film has a potential to control large currents using its transition between a superconducting state and a normal conducting state. In this paper an equivalent circuit model of a HTS thin film is presented to design a power conditioning circuit as an inverter which can handle large currents at voltages less than 1V. Device model parameters of a HTS thin film were determined by comparing quenching characteristics calculated by a circuit simulation program (PSpice) with those measured experimentally. A temporal behavior of resistance of the HTS thin film quenched by a self-current which was simulated using the model were compared with experimental results. An inverter circuit using the HTS thin film switched thermally is designed and the characteristic of a switching operation with a photovoltaic cell is also shown.