摘要
在绝缘子各种闪络故障中,不明原因引起的闪络占有相当比例,这其中环境因素的影响较为突出。为此,特设计风洞试验,模拟绝缘子受大风影响的实际运行情况,研究不同风速对绝缘子闪络电压的影响,找出强风环境下绝缘子闪络特性,进而提出相应防范措施。试验结果表明,复合绝缘子闪络电压随风速增大而升高,而对瓷质绝缘子,超过20m/s风速后闪络电压会随风速增大而降低。分析认为,上述现象是绝缘子表面积聚了一定量的表面电荷,从而使绝缘子表面电场发生畸变,进而影响运行电压下绝缘子沿面放电的整个过程。最后又对表面积聚电荷对绝缘子闪络电压的影响进行了仿真计算,证实了当积聚电荷密度过大时会导致同样电压下电场强度的增加,确实可能会导致闪络电压的下降。
A wind tunnel test was specially designed to simulate the effect of wind scrapping on insulator flashover,and the influence of different wind velocity and wind direction on insulator flashover voltage was studied.Meanwhile,the mechanism of insulator flashover was researched under wind scrapping,and corresponding preventive measures were taken.The experimental results show that the flashover voltage always increases with wind speed rising.A certain amount of surface charge accumulates on the surface of ceramic insulator which makes the electric field distortion of insulator surface,and then affects creeping discharge of insulator under operating voltage.Moreover,the effect of surface charge accumulation on flashover voltage of ceramic insulator is simulated,and the results prove that,when the density of surface charge is excessively high,the electric field strength will increase significantly under the same voltage which possibly lowers flashover voltage of insulator.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2011年第1期227-233,共7页
High Voltage Engineering
基金
国家重点基础研究发展计划(973计划)(2009CB724508)~~
关键词
绝缘子
无明闪络
积聚电荷
闪络电压
风洞试验
风速
insulator
unidentified flashover
accumulation charge
flashover voltage
wind tunnel test
wind velocity
