A Study on the Dielectric Design of the High-Voltage Platform for Developing the 28 GHz ECRIS at the KBSI

Currently, the 28 GHz ECRIS (electron cyclotron resonance ion source) was developed to produce a high-current heavy-ion beam at the KBSI (Korea Basic Science Institute). The high-voltage platform of the 28 GHz ECRIS is essential to deliver an ion beam to the next acceleration stage. The high-voltage platform was designed considering dielectric characteristics in order to ensure electrical safety. In this paper, a study on the dielectric characteristics of GFRP (glass- fiber-reinforced plastic) is performed to determine the thickness of the GFRP cylindrical shell located between the plasma chamber and the warm bore of the superconducting magnet cryostat. The dielectric experiments on a GFRP cylindrical shell were conducted under a DC voltage. Sphere-to-plane electrode systems were used to examine the dielectric characteristics. Also, the relationship between the dielectric characteristics of the GFRP cylindrical shell and the distribution of the electric field intensity was calculated and analyzed by using FEM (Finite Elements Method) simulations.