水珠对复合绝缘子表面电场畸变特性的影响

Effect of Water Drop on Electric Field Distortion of Composite Insulator

潮湿环境中,凝结在绝缘子表面的水珠会畸变其表面电场。以FXBW4-10/100型复合绝缘子为研究对象,利用COMSOL软件对10kV直流电压作用下该型绝缘子表面有无水珠凝结时的电场进行了数值模拟;以电场强度和场强畸变率为评价标准,分析了水珠相关参数(粒径、间距、电导率、相对介电常数)对该绝缘子表面电场畸变特性的影响。结果表明:水珠表面的电场强度远高于其周围电场,而其内部则反之;水珠的粒径、间距和相对介电常数对该绝缘子表面电场强度的畸变影响均较大,畸变率最高可达573%,而其电导率的影响则较小;水珠距离绝缘子中轴线越远,其场强畸变率一般越大,且多集中于复合绝缘子的边缘处,易引发污闪。

In a humid environment,the electric field on the insulator surface will be distorted by the water droplets condensed on the insulator surface.In this paper,the FXBW 4-10/100 composite insulator was taken as the research object.The electric field of the insulator with or without water drops under 10 kV DC voltage was simulated by COMSOL software.The influence of the water drop related parameters(particle sizes,spacing,conductivity,and relative dielectric constant)on the electric field distortion characteristics of the insulator surface was analyzed with the electric field intensity and its distortion rate as the evaluation criteria.The results show that the electric field intensity on the surface of the water drop is much higher than that around it,while the electric field intensity inside the water drop is much lower.The particle size,spacing and relative permittivity of the water drop all have a great influence on the distortion of the electric field strength on the insulator surface with the distortion rate is even up to 573%,while the influence of the conductivity is small.The farther the water drop is from the central axis of the insulator,the higher the electric field intensity.The areas with high distortion rate of field strength are mostly concentrated at the edge of the composite insulator,which is easy to cause pollution flashover.