Study on the Enhancement of Surface Flashover Voltage of PTFE by DBD Plasma Treatment

Polytetrafluoroethylene (PTFE) is well-known for its outstanding insulation properties, thermal stability, and chemical resistance, which has been extensively used as insulating material in high voltage power equipment. With the continuous increase of voltage levels, surface flashover has become a crucial challenge for insulation protection. This work uses dielectric barrier discharge (DBD) plasma method to perform surface fluorination treatment on PTFE to further improve its surface flashover characteristics. The results show that fluoride are successfully grafted onto the surface of the sample. The surface roughness of PTFE increases first and then decreases with treatment time, and the flashover voltage along the surface reaches its maximum value at 2 minutes, an increase of 45.9% compared to the pristine, revealing the mechanism between surface morphology and flashover voltage. Appropriately increasing the surface roughness can help increase the specific distance of surface electron creep, thereby increasing the flashover voltage along the surface.