Study of Hybrid-Type Field Coil for Superconducting Rotating Machines

This study examines a hybrid-type superconducting field coil that exploits the advantages of a permanent magnet and an electromagnet-type coil to mitigate the weaknesses of a conventional superconducting field coil with a power supply. The hybrid-type superconducting field coil proposed in this study can be applied to improve the performance of conventional superconducting rotating machines. One of the biggest problems of conventional superconducting power generators is the large fluctuation in the output voltage due to the fluctuation in the load. However, the hybrid-type superconducting field coil can be applied to superconducting power generators to stably control the electromotive force of the field and to effectively reduce the fluctuation in the output voltage. This study uses a high-temperature superconductor (HTS) 2G wire to manufacture a test model for the innovative superconducting field coil. A proof-of-principle test using the finite element method was conducted, and the performance of the coil was verified through an experiment.