Creeping Discharge Phenomena along Aerial Insulated Wire

在高压架空配电系统中，架空绝缘线由绝缘子和电灯杆上的绑扎线支撑。当雷击发生在他们附近时，雷电波就会侵入电线的中心线。如果绝缘子在雷电冲击下发生闪络，则可沿导线表面产生蠕变放电。然后，导线暴露在导线熔化失败的危险中。为了防止这一事故的发生，对蠕变放电的解释是非常重要的。我们研究了在峰值Vm=±90，±100KV，波前持续时间Tf=1.2-100.0μs的冲击电压作用下，沿导线表面产生的蠕动放电的特性。正切向放电：(1)发展长度不受波前持续时间Tf=1.2-8.0μS的影响，当波前持续时间Tf=10.0-100.0μS时，随着波前持续时间的延长，发展长度变短。(2)方面沿线材表面发展，跳跃与Tf和Vm无关。负蠕变放电：(1)发展长度：在Tf=1.220μ的S，发展长度随Vm的增加而出现增减区，在Tf=50和100μ的S，发展长度随Vm的增加而单调增加，但随着Tf的增加，发展长度呈抑制趋势。(2)Vm≦100kV放电尖端发生的离散跳跃现象随Tf的增大而受到抑制。结果表明，在负蠕变放电中，放电尖端跳跃现象的减弱使发展长度变长。

In high voltage aerial distribution systems, the aerial insulated wires are supported by the insulators and the binding wires at the electric light poles. When the lightning strike occurs in their neighborhood, a lightning surge invades to the central line of wire. If the flashover of insulator happens by the lightning surge, the creeping discharge can develop along the wire surface. Then, the wires are exposed to danger of the wire melting failure. In order to prevent this accident, the elucidation of the creeping discharge is very important.We investigated the property of creeping discharge which develops along the wire surface under the impulse voltage application with peak values Vm=±90, ±100kV and duration of wave fronts Tf=1.2-100.0μS. It has been clarified as follows.1. Positive ceeping discharge :(1)Developing length The developing length does not influenced by the duration of wave front Tf=1.2-8.0μs. At durations of wave front Tf=10.0-100.0 μs, the developing length becomes short when the duration of wave front becomes long. (2)Aspect It develops along the wire surface with jumping independent of Tf and Vm.2. Negative creeping discharge :(1)Developing length The increase and decrease regions of the developing length appears with the increase of Vm in Tf=1.2-20μs. The length increases monotonously with the increase of Vm in Tf=50 and 100μs. However, the developing length shows a restrained tendency with the increase of Tf. (2)Aspect The discrete jump phenomenon which occurs at the discharge tip in Vm≦100 kV is restrained with the increase of Tf. It was clarified that the decline of the jump phenomenon at the discharge tip in the negative creeping discharge made a developing length long.