强寒潮下超高压输电线路直流融冰效果差异分析

Analysis on Differences in DC De-icing Effects on EHV Power Transmission Lines Under Strong Cold Wave Weather

针对强寒潮天气下超高压输电线路各区段直流融冰效果存在差异的实际案例,根据输电线路覆冰在线监测数据和现场信息,结合输电线路运行参数以及直流融冰技术相关原理,开展了气象环境、覆冰情况及直流融冰参数间的关联性分析。结果表明:地线等效覆冰厚度较大导致融冰所需时间更长,现场气温较低、风速较大导致覆冰完全脱落所需的融冰电流有所增加,而实际融冰电流小于所需融冰电流导致覆冰未完全脱落。建议在融冰电流一定的基础上,若线路覆冰厚度较大,需适当延长融冰时间;若要短时间内取得较好的融冰效果,需适当增加融冰电流;在融冰时间一定的基础上,若线路环境气温较低或风速较大,需适当增加融冰电流。

In allusion to actual cases of differences in DC de-icing effects on EHV power transmission lines under strong cold wave weather, this paper analyzes relevance among weather environment, icing situations and DC de-icing parameters ac- cording to online monitoring data of icing of power transmission lines and field information combining with operational pa- rameters of power transmission lines and relevant principles of DC de-icing technology. Results indicate that equivalent icing thickness of earth wire is quite big which causes more longer de-icing time, and low field temperature and larger wind speed cause required de-icing current for icing fall-off increase while actual de-icing current is less which causes icing not fully cleared. It suggests to properly delay de-icing time if icing thickness of the line is big on the basis of certain de-icing current, or increase de-icing current in order to acquire better de-icing effect in short time. In addition, on the basis of certain de-ic- ing time, it is suggested to properly increase de-icing current if environmental temperature of the line is lower or wind speed is larger.