Analysis and Effectiveness Verification of Partial Discharge Online Detection Technology for 35 kV Switchgear

The operational reliability of 35 kV switchgear significantly impacts power system safety, with partial discharge serving as a crucial early indicator of insulation failure and equipment faults. To enhance the detection and early warning capabilities for partial discharge in switchgear, this paper analyzes the disaster-causing mechanisms of partial discharge induced by insulation degradation and typical on-site defects. Based on this analysis, an online partial discharge detection method utilizing TEV and ultrasonic multi-dimensional sensing is proposed, along with a signal acquisition and baseline offset threshold early warning mechanism. Field tests conducted on a 35 kV switchgear paralleling project demonstrate that the proposed method can effectively identify and provide early warning for partial discharge activities in switchgear, offering technical references for condition monitoring and fault prevention of distribution equipment.