Risk Of Partial Discharge And Flashover-like Events In Wedge-shaped Tension Clamps Under Polluted Conditions

At high-voltage transmission line sites, the electrical insulation performance of fiber optic dead end clamp is significantly affected by the environmental medium. When particulate matter, salt spray, or industrial pollutants deposit on the surface of the fittings, the surface electric field distribution changes, and the enhanced local electric field causes abnormal emission from the previously safe insulation gaps. When fixed dead end clamp is in a harsh environment, the pollutants interact with the water film to form a conductive path, which reduces the insulation strength and increases the probability of surface discharge evolving into a high current channel, thus causing a phenomenon similar to flashover.

The structural design of the dead end clamp is intended to mechanically lock the wires through a wedge fit while maintaining a stable contact interface. In clean operating environments, the structure's favorable electric field distribution reduces the incidence of partial discharge. However, under conditions of severe contamination, the combined effect of contaminant conductivity and ambient humidity alters the local potential at the contact points, making discharge signs more likely to appear and gradually concentrating energy, potentially developing from weak surface discharge into a discharge channel spanning the local gaps in the fittings.