Title |
Analysis on the Dielectric Characteristics of Vacuum to Develop HTS Magnets |
Authors |
Woocheol Shin ; Bimaridi Afif ; Junyoung Park ; Bonhyuk Ku ; Hobin Lee ; Hyoungku Kang |
DOI |
http://doi.org/10.5207/JIEIE.2023.37.2.030 |
Keywords |
Electrical breakdown experiment; Empirical formula; HTS; Insulation design; Saddle coil; Vacuum |
Abstract |
The high-temperature superconducting (HTS) magnet used in particle accelerators for cancer treatment exhibits a large current change for a short period of time due to its fast ramp-up characteristics, which results in high voltage and instant vulnerability to electrical insulation. This research introduces the saddle-coil, which, due to its complex shape and small bending radius, allows for the local concentration of electric field intensity. Reports from the European particle physics laboratory, CERN have revealed dielectric breakdown due to 1000V between layers during low-temperature superconducting (LTS) magnet experiments for accelerators, yet no research has been conducted to solve this problem. HTS magnets operating in vacuum may be susceptible to electrical breakdown due to high induced voltage and local quench due to rapid-ramp characteristics. Therefore, this paper deals with the dielectric characteristics of vacuum to develop an electrically stable HTS magnet. Specifically, dielectric experiments on penetration and creepage discharge were conducted under various vacuum conditions, and empirical formulae for calculating the electric field intensity at sparkover for the insulation design of HTS magnets was derived. |