Abstract
An accident in high voltage aerial distribution systems such as punch-through breakdown, disconnection of wire can often occur by the invasion of lightning overvoltages. This is due to the generation of creeping discharges traveling over the insulated wire surface. The detailed study on creeping discharge characteristics is a most important to the prevention of such accidents. In the previous our paper, it was clarified that when a standard lightning impulse voltage was applied to either the central line of the sample wire or the binding wire, there was a remarkable difference in the lengths of creeping discharges.
In this paper, we clarify that the lengths and aspects of creeping discharges when an impulse voltage is applied to the central line of wire are significantly affected by the electric field strength of wire surface. These results will be useful to the optimum design for the insulation of aerial distribution systems.
