Research on Electromagnetic Fault Detection Method for CRAFT Magnet Power Transmission Busbar

High-current busbars are critical components in superconducting magnet power supply systems for fusion devices. During long-pulse operation, busbar faults such as insulation degradation or short circuits can lead to catastrophic failures, impacting both electrical equipment and superconducting magnets. This paper proposes an electromagnetic detection method for diagnosing busbar faults by analyzing changes in the surrounding magnetic field. Using a bipolar stacked busbar model, we establish a theoretical framework for detecting shortcircuit and grounding faults through magnetic field variations. Finite element simulations validate the method's effectiveness under 30 kA and 300 kA operating conditions. Experimental results demonstrate that the magnetic field asymmetry caused by faults can be reliably captured via distributed sensors, enabling real-time health monitoring. This approach provides a novel solution for fault detection in high-current fusion busbars, significantly enhancing operational safety.