覆着藻类对110 kV复合绝缘子电场分布的影响研究

Influence of Algae Overlay on Electric Field Distribution of 110 kV Composite Insulators

潮湿环境下绝缘子表层覆着藻类影响其电压分布特征,对输电线路污闪防护影响较大。采用ANSYS仿真计算软件建立110 kV复合绝缘子二维电场计算模型,计算分析藻类生长位置、天气情况、生长状况等因素对绝缘子电场分布的作用规律。结果表明:绝缘子电场呈"U"形分布,在导线端护套与金具的交界处出现电场峰值;藻类生长越靠近高压端电场畸变越严重,低压端伞裙有藻类生长时,电场分布和清洁时大致相同,但球窝处场强减小;雨天时,导线侧金具与伞裙交界处的极大值并没有明显变化,低压端场强明显增大,藻类生长位置与水带交界处电场畸变严重,闪络风险较高;藻类形成干燥带对场强的影响不显著,轴向场强在干燥带处略微增加,低压端伞裙护套交界处电场强度有所减小,发生闪络的风险较低。

Under moist environment, algae coating on the surface of insulator would affect its voltage distribution characteristics, which has great influence on the pollution flashover protection of transmission line. In this paper, a two-dimensional electric field calculation model of 110 kV composite insulator was built using ANSYS simulation software, and the functional rules of weather conditions, algae growth location and growth condition factors on the electric field distribution of insulators were calculated and analyzed. The results show that the electric field of insulator shows U-shape distribution, and the peak value of electric field appears at the junction of wire end sheath and gold fixture. The closer the algae grows to the high voltage end, the more serious the electric field distortion is. When the algae grows on the low voltage end umbrella skirt, the electric field distribution is much the same as that of clean insulator,but the electric field intensity decreases at the ball socket. On the rainy days, there is no significant change of the maximum value at the junction of the wire side gold and umbrella skirt, but the field strength at the low voltage end increases obviously, the electric field intensity at the junction of the algae growth position and the water belt distorts seriously, so the flashover risk is high. The dry band formed by algae has no obvious effect on the field strength, the axial electric field intensity increases slightly, and the electric field intensity at the junction of skirt sheath at the low voltage decreases, so the flashover risk is low.