Development of an Online Partial Discharge Monitoring System for Hydroelectric Generators Using Neutral Point CouplingLI Chengcheng¹, WAN Yuan₁^, PANG Pingheng¹, TANG Wei², CAO Wang¹(1. Hunan Wuling Power Technology Co., Ltd, Changsha 410007, China;)

Partial discharge is a crucial indicator for evaluating the insulation condition of generators. To address the issues of low sensitivity and poor reliability in existing online monitoring devices, this paper designs a broadband capacitive coupler sensor and develops a partial discharge online monitoring system based on the ARM+FPGA architecture. Experimental results show that the system possesses high sensitivity and good reliability, enabling data acquisition and analysis for different discharge models. The proposed system demonstrates favorable applicability and engineering value for online partial discharge monitoring in generators.