Analysis and Treament of a Nuclear Power Plant Inverter Fault Shutdown Event

This paper focuses on a fault shutdown event of the Inverter A in the 220V Uninterruptible Power Supply (UPS) system of the conventional island at a domestic nuclear power plant. By integrating the inverter"s operational control logic and wiring principles, the primary and secondary circuit connections were inspected, the internal component boards were checked, and the current sampling circuit was analyzed. The fault location and root cause of the abnormal shutdown were identified. A feasible optimization scheme for defect elimination was proposed, effectively improving the reliability and safety of the inverter operation.