A superconducting switch using induced current in the closed loop circuit

Abstract

Superconducting magnets have been applied in many fields because of the high magnetic field and the low loss. In order to energize superconducting magnets and operate them in the persistent current mode, the superconducting switch is essential. Recently, a superconducting switch using the interaction between the DC transport current and induced current in a closed loop circuit has been proposed, which cannot only respond fast, but also operate efficiently. In this work, an analytical model based on equivalent circuit is proposed to explain the working principle of this type of superconducting switch. An experimental protype is built to investigate its electromagnetic behaviours and working performance. Impacting factors of the voltage across the superconducting switch have been clarified based on experimental results. The method based on asymmetric AC magnetic field is proposed to enhance the average voltage across the superconducting switch and its performance has been verified through experimental tests. Besides, the advantages and application prospects of the superconducting switch are discussed.