特高压交流输电线路瓷绝缘子串电位和均压环电场分布计算模型的简化

特高压交流输电线路绝缘子串电位和均压环表面电场分布计算有限元模型具有模型尺寸大、结构复杂、媒质种类多的特点。为保证计算精度,需全面分析相关因素的影响,以合理简化计算模型,提高计算效率。该文建立了特高压交流输电线路瓷绝缘子串的三维静电场有限元全模型和简化模型,全面分析了杆塔、导线、连接金具、联板及相间作用等因素对电位和电场分布的影响,最后验证模型简化的合理性。全模型和简化模型计算结果对比表明,将三相导线控制在一定长度、对杆塔合理简化、省略联板和金具并且只建立单相绝缘子串模型的简化方法可行,用简化模型代替完整模型进行绝缘子串电位和均压环表面电场分布的分析能够减小计算规模,提高绝缘子串和均压环参数优化配置分析效率。

Calculation Model Simplification for Porcelain Insulator String Potential and Grading Ring Surface Electric Field Distribution of UHV AC Transmission Line

The finite element model of UHV AC transmission line porcelain insulator string potential distribution and the grading ring surface electric field distribution calculation have characteristics of large sizes,complicated structures and various media.To ensure the calculation accuracy,the related influential factors should be considered thoroughly to simplify the model reasonably.Conseuently,a whole 3D finite element model and a simplified one of UHV AC transmission line porcelain insulator string were estabilshed.Several influential factors,including tower,phase conductors,hardware fittings,yoke plate,and phase interaction were considered in the analysis of the potential and electric field distribution.The reasonability of the simplified model was also validated.The comparison results show that establishing a simplified model of three-phase bundled conductors within a certain length by simplifying the tower reasonably,omitting the hardware fittings and yoke plate,and containing only single-phase insulator string model are feasible.The simplified model can replace the complete model for analyzing the potential distribution along the porcelain insulator string and the electric field distribution on the grading ring surface,and it can reduce the calculation scale and improve the optimization efficiency of insulators string and grading ring parameters.