藻类附生对35kV绝缘子式限压器电场分布影响研究

Study on the Influence of Algae Epiphytic on the Electric Field Distribution of 35kV Insulator Type Voltage Limiter

绝缘子式限压器兼具雷电防护与绝缘支撑双重作用,相比于普通绝缘子,潮湿环境下绝缘子式限压器表层附生藻类对伞裙表面电场及闪络电压影响更大。笔者采用Ansoft仿真计算软件建立35 k V绝缘子式限压器二维电场计算模型,研究表层附生藻类生长位置、生长状况、天气情况等因素对伞裙表面电场分布作用规律。计算结果表明:绝缘子式限压器电场呈"W"形分布,相比于限压段,绝缘段承受了较大的电压和场强;场强最大值出现在下金具上沿,在下限压段护套与金具的交界处出现一个电场峰值;藻类附生越靠近下限压段电场畸变越严重,上限压段附生藻类时,电场分布和清洁伞裙大致相同,但球窝处场强减小;雨天情况下,导线侧金具与伞裙交界处的极大值无明显变化,但绝缘段场强增幅较大,藻类生长位置与水带交界处电场畸变严重,闪络风险较高。研究结论为新型绝缘子式限压器在暖热高湿地区的应用与维护提供理论参考。

Insulator type limiter has the dual function of lightning protection and insulation support,compared with the ordinary insulators,algae epiphytic on the surface of insulator type voltage limiter in humid environment have a greater influence on the surface electric field and flashover voltage of umbrella skirt.An soft simulation software is used to establish a two-dimensional electric field calculation model of 35 k V insulator voltage limiter,aiming at the effect of growth position,weather conditions,growth status and other factors of the surface epiphytic algae on the electric field distribution on the surface of the umbrella skirt. The calculation results show that the electric field of insulator type limiter is "W"shape distribution,and the insulating section is subjected to large voltage and field strength compared with the pressure limiting section. The maximum field intensity appears on the lower gold fixture,and an electric field peak appears at the junction of the lower limit pressure section sheath and the gold fixture. When the upper bound pressure section is attached to the algae,the electric field distribution is roughly the same as that of the cleaning umbrella skirt,but the field strength of the spherical nest decreases. In the case of rainy days,there was no significant change in the maximum value at the junction of the wire side gold and the umbrella skirt,but the field strength of the insulating section increased greatly,the growth position of algae and the junction of water belt have serious electric field distortion and high flashover risk. The conclusion of this paper provides a theoretical reference for the application and maintenance of a new type of insulator voltage limiter in warm high humidity area.