Progress Towards a REBCO Homopolar Motor With the Gallium-Indium-Tin Sliding Contacts

Development of homopolar electric machines is a promising superconducting application. A homopolar motor with a 2G high-temperature superconducting (HTSC) magnetic system and copper disk rotor is designed at the NRC “Kurchatov Institute”. The advantages of such electric machines are considered. The liquid metal sliding contacts based on a gallium-indium-tin alloy are considered as a safe alternative to toxic mercury or NaK alloys. The homopolar motor controlling by a proportional-integral-differentiating (PID) algorithm is simulated and checked experimentally. The results of the preliminary tests of HTSC magnetic system and liquid metal contact are also reported.