Study on the Electromagnetic Characteristics of REBCO High-Temperature Superconducting Tapes under Transverse Alternating Electromagnetic Loads

The fatigue behavior of dynamic superconducting magnets (such as high-speed maglev vehicle magnets) under transverse alternating electromagnetic loads is closely related to their operational safety. The traditional mechanical vibration testing method for complete magnets fails to directly simulate the loads on the superconducting layer, being a post-manufacturing qualification test. In this paper, a testing method that directly applies transverse alternating electromagnetic forces is developed for the typical weak structure of the magnet, namely, a single suspended tape. Combining mechanical analysis and simulation models, we attempt to simulate the performance changes of magnets under actual working conditions and at resonant frequencies within the range of 40-500 Hz. The experimental results show that under the conditions of an external magnetic field strength of about 640 mT and 10⁶ cycles, the critical current ($I_{c}$) attenuation of REBCO high-temperature superconducting tapes is generally less than 5%. To study more severe conditions, the samples were artificially pre-damaged, and no significant additional damage was observed. This method will provide a low cost new approach for verifying the fatigue performance of dynamic magnets under transverse alternating electromagnetic loads.