污秽对红外成像法测零值绝缘子影响的有限元分析

Finite Element Analysis on Influence of Pollution on Detecting Faulty Insulators by Infrared Imaging Method

为研究污秽对绝缘子串电压分布及红外热像法测零值绝缘子的影响,以110 kV绝缘子串为例,采用有限元分析方法对不同污秽条件下含零值及正常绝缘子串的电压分布进行了多组仿真对比试验。结果表明:零值绝缘子位于两端比位于中部对绝缘子串电压分布的影响更大;随着等值盐密的增大,绝缘子串电压分布趋于均匀,零值绝缘子负温升特征的显著性有所下降;绝缘子串下表面覆污时的电压分布比上表面覆污时更均匀;当两端污秽度大时,绝缘子串的分布电压在中部最高。

In order to investigate the influence of pollution on the voltage distribution of insulator strings and the decection of faulty insulators by infrared imaging method, the voltage distribution of 110 kV insulator strings with and without faulty insulator was simulated and compared by finite element analysis under different content of pollution. The results show that the effect of faulty insulator at the end of insulator string on the voltage distribution is bigger than that in the middle. With the increase of the equivalent salt deposit density, the voltage distribution of insulator string tends to be uniform, and the significance of negative temperature rise of faulty insulator decreases. When the lower surface of insulator string is polluted, the voltage distribution of insulator string is more uniform. When the pollution is heavy at both ends of insulator string, the middle of insulator string has the highest voltage.