Characteristics of Exciting Power Lead-less Superconducting Magnet by Multi Magnetic Flux Pump

Abstract

For exciting superconducting magnets has been used conventional power supply and power lead system. This way has some problems: heat leak into the cryogenic parts, occurrence of Joule loss in the power leads, etc. To cope with such problems, the use of superconducting magnetic flux pump has been studied. The magnetic flux pump can serve a large persistent current in superconducting magnets without switch and power leads, keeping to supply large current. However, the design method of the flux pump has not been well-known yet. Therefore, we have developed aa small size magnetic flux pump for analysis purposes to investigate its characteristics and actual performances when exciting a superconducting magnet. Furthermore, we set up a new type equipment which can connect many flux pumps compactly, so we have theoretically and experimentally examined the method to improve performances of the flux pump. As a result, we additionally derived some new important design parameters. This paper also gives a comparison between theoretically-calculated and experimental results for the case of parallel and multi-connected flux pump devices, respectively. Further it is clarified that the multi connection of the flux pump can improve performances.