Conceptual Design of Quench Detection System for High Field ITER Magnet using Wireless Power Transfer Technology

Abstract

The superconducting wires have been developed for high field magnet, transformers, motors and so on. The quench detection and protection system are essential for safety operations of the HTS facilities. The high voltage signal conditioner (HVSC) method is generally used for the quench detection and protection, however especially for high voltage operation magnet such as international thermonuclear experimental reactor (ITER) magnet (56 kV, DC), it is difficult to apply to HVSC method due to the risks in terms of high voltage sparks. As well as, the power supply for HVSC should be isolated since the ITER magnets, which is supplied by 15 MA, generate about 10 T (tesla) strong magnet. To solve these problems, insulation resistance of power supply should be larger than 500 MΩ; a lower resistance can affect the common-mode voltage of the differential amplifier in the HVSC system. From these reasons, the wireless power transmitter (WPT) system has been considered as one of reasonable options to solve insulation resistance obstacles since WPT system can transfer power through any non-metallic media between antenna (Tx) and receiver (Rx) coils. In this study, authors described the conceptual design and fundamental performances of quench detection system for high field magnet based on resonance coupling method with RF power of 370 kHz 200 W.