特高压交流输电线路复合绝缘子和均压环场强影响因素

Influencing Factors of Composite Insulator and Grading Ring Surface Electric Fields in UHV AC Power Transmission Lines

1 000 kV特高压交流输电线路复合绝缘子和均压环表面电场分布数值仿真研究具有媒质种类多、几何结构复杂、计算量大等特点。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。通过建立特高压交流输电线路双联复合绝缘子的三维静电场有限元全模型和简化模型,研究了导线、杆塔、金具、联板等因素对复合绝缘子和均压环表面电场分布的影响,验证了模型简化的合理性。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、省略联板和金具的简化方法可行,用简化模型代替完整模型进行复合绝缘子电位分布、电场分布以及均压环表面电场分布的仿真研究,可有效降低计算规模,提高特高压交流输电线路绝缘子和均压环参数优化配置分析效率。

The numerical simulation study on the composite insulator and grading ring surface electric field distribution in UHV AC power transmission line has the characteristics of the various mediums, the complicated structure and the large amount of calculation. In order to assure the calculation accuracy, related influencial factors should be comprehensively analyzed to reasonably simplify the calculation model and enhance computational efficiency. A whole and a simplified 3D finite element model of double composite insulator in UHV AC transmission line was built. The influences of conductors, towers, hardware fittings, yoke plate on the composite insulator and grading ring surface electric field distribution were studied. Finally, the reasonability of the simplified model was validated. The comparison results between whole model and simplified model show that the simplification of tower is reasonable, and the simplification method that omits the hardware fittings and yoke plate is feasible, with controlling three-phase bundled conductors within a certain length. The simplified model can replace the whole model to analyze the electric field and potential distribution of the composite insulator and the electric field distribution on the grading ring surface, and it can reduce the calculation scale, as well as improve the analysis efficiency of parameters optimization for the insulators string and grading ring in UHV AC transmission lines.