Estimation of Current Decay Performance of HTS Electromagnet for Maglev

This paper deals with the estimation of current decay rates resulting persistent current mode (PCM) performance and its affect on design of high temperature superconducting (HTS) coil models used in an HTS electromagnet. The HTS coil models were designed to generate the required magneto motive force(MMF) on HTS electromagnets operating at various levitation gaps. We simulated the current decay rate with the self-inductance and joint resistance of the superconducting coil. The current decay rates of the models for the 10 mm levitation gap were in the range of 4.5% to 18%, whereas current decay rates of the models for the 25 mm levitation gap were in the range of 2.2% to 5.3%. It was found that the HTS electromagnet for large levitation gaps had more advantages than those for narrow air gaps in regards to designing an HTS coil with better PCM performance.