表面缺陷对复合绝缘子电场电势分布的影响

Effect of Surface Defects on Electric Field Potential Distribution of Composite Insulators

针对复合绝缘子表面缺陷会使电场发生畸变并破坏硅橡胶的憎水性的问题,在有限元仿真软件COMSOL中建立复合绝缘子三维模型,分析了不同位置的缺陷以及缺陷内染污对复合绝缘子电场电势分布的影响,并进行闪络试验。结果表明:受缺陷的影响,电势因位置不同而变化规律不同;缺陷处电场升高,峰值出现在伞裙与芯棒护套交界附近;缺陷内染污后,缺陷内电场成倍升高,以伞裙与芯棒护套交界附近尤为突出,且会影响到整个伞面的电场使之升高;洁净缺陷会使复合绝缘子的闪络电压降低,芯棒护套上的缺陷使闪络电压降低的幅度更大。

The surface defects of composite insulators will distort the electric field and destroy the hydrophobicity of silicone rubber.A three-dimensional model of composite insulators is established in the finite element simulation software COMSOL.The effects of defects in different positions and internal contamination on the electric field potential distribution of composite insulators are analyzed,and the flashover test is carried out.The results show that the electric potential affected by the defect varies with different positions;the electric field at the defect increases and the peak value appears near the junction of the umbrella skirt and the mandrel;after the defect is contaminated,the electric field in the defect increases exponentially,especially near the junction between the umbrella skirt and the mandrel,and will affect the electric field of the whole umbrella surface to make it rise;clean defects will reduce the flashover voltage of composite insulators and the defects on the mandrel will be reduced more greatly.