Design and test of a superconducting power supply with YBCO coated conductor load

This paper deals with the design and test of a high temperature superconducting (HTS) power supply with YBCO coated conductor (CC) pancake load, also presents its operational characteristics through experiments. HTS power supply consists of two heaters, an electromagnet, a solenoid, and a pancake load of about 0.73 mH. The solenoid and pancake load were fabricated by using YBCO CC. The timing sequential control of two heaters and an electromagnet is an important factor to generate pumping-current in the pancake load. The heat transfer analysis of heater triggering parts of the YBCO CC solenoid according to the heater input was carried out. Based upon the analysis, the 3 A electromagnet current and the 0.55 A dc heater current were optimally derived, and 4 s, 8 s and 16 s for the pumping period were selected in this experiment. A region of the superconducting tape with a buried heating coil can be switched by means of its temperature change. In order to measure the pumping-current with respect to the magnet flux changes, a hall sensor was installed at the center of the YBCO CC pancake load. In the experiment, the maximum pumping current reached about 20 A.