Real-time detection system for magnetic island position of the neoclassical tearing mode in plasma

A dedicated real-time detection system (NTM-RTDS) has also been developed to determine the radial position of neoclassical tearing mode (NTM) magnetic islands. Built upon the LabVIEW real-time framework and PXIe architecture, it adopts a distributed upper-lower computer structure that enables high-speed acquisition and real-time processing of signals from magnetic probes and electron cyclotron emission diagnostics. By analyzing perturbation frequencies associated with magnetic island rotation and electron temperature profile variations, the system achieves island localization within a 10 ms cycle. Validation on experimentally advanced superconducting tokamak confirms a detection accuracy of 80.25% in identifying magnetic islands, verifying the system's robustness. The NTM-RTDS thus represents a critical instrument for enabling active, real-time NTM control via electron cyclotron resonant heating, and provides a foundational platform for real-time disruption mitigation strategies in future large-scale fusion experiments, including the international thermonuclear experimental reactor.