Study on Surface Discharge Test of Combination of Insulating Shielding Covers for Live Working

In the distribution network live working, in order to improve the insulation protection area, insulation shielding covers are often used in combination. In this paper several common insulating shield appliance, surface discharge tests were carried out. The surface discharge test uses a ball-rod electrode to simulate field operation conditions and observe the discharge path with a high-speed camera. The test results show that the material types of insulating masks have a great influence on the surface insulating properties, the insulating properties of rubber masks and plastic masks are close, and the surface insulating properties of resin masking utensils are lower. Resin insulation blanket used in combination, overlapping parts of the more closely fit. When the overlap length is 15 cm, the surface discharge voltage in the overlap region of the resin insulating blanket is close to that of the rubber blanket. Considering the maximum operating voltage of 10kV distribution line is 11.5kV, the length of the overlapping parts is not less than 5cm.