Structure Optimization of Fast Discharge Resistor System for Quench Protection System

In the quench protection (QP) process of superconducting fusion devices, the operating reliability and efficiency of power components are affected by stray parameters of the fast discharge resistor (FDR) system, especially the system stray inductance. In this paper, the fundamental condition of the QP operating process and the large power FDR system structure layout for the Large-scale Superconductor Test Facility (LS II) are presented. The negative affected VCB, CPC circuit action, and the energy discharging process are further analyzed. The stray inductance optimization method of the resistor module and structure connections are proposed to reduce the stray inductance value. Finally, the optimization results are presented by the Q3D module of the FLA software.