Thermal and Electromagnetic Design of a Superconducting Coil

This article presents the methodology followed for the thermal and electromagnetic design of a superconducting coil at the University of Western Macedonia, Kozani, Greece, aimed to be used in a unique superconducting magnetic energy storage system for laboratory education and research purposes. First, we discuss the design constraints of the coil and select its dimensions using both the electromagnetic finite element method (FEM) and analytical equations based on the available length of a YBCO high-temperature superconductor. Then, we select the position of the coil inside a vacuum chamber. Then, an initial experiment without thermal load is performed to measure the cooling characteristics of the cryocooler. Using the results of the experiment and employing thermal FEM, we obtain an approximation of the cryocooler's cooling power versus time. After placing the coil and the thermal shield in the selected position inside the chamber, we carried out an experiment to measure the cooling curve with the load attached. The cryocooler's cooling power is approximated using the same FEM procedure. Thus, for this specific thermal load, the behavior of the apparatus is known. The methodology followed for the design of this unique system can be easily replicated by other researchers.