Discharge characteristics of metal particles attached to the insulation rod of a circuit breaker under the action of impulse voltage

This article addresses the issue of partial discharge triggered by metal particles adhering to the insulation rod of a circuit breaker. We designed an equivalent cross-sectional model for the rod and established an impulse voltage experimental platform to investigate particle discharge characteristics under various influencing factors. Our research reveals that the characteristic curve of particle discharge frequency is divided into low and high active regions by the "active point". The height of the "active point" is influenced by its size, position, and quantity. As the average discharge frequency and discharge amplitude increase, the "active point" rises. The amplitude characteristic curve for single particle discharge exhibits a stepwise rise, whereas the curve for multiple particles displays a peak or wave shape. This study elucidates the hazards posed by particles to insulation rods under impulse voltage due to various factors, offering a theoretical foundation for hazard mitigation.