500 kV变电站绝缘子串均压环结构优化分析

Optimization analysis of grading ring structure for insulator string in a 500kV substation

为改善变电站绝缘子串的电磁工作环境,同时满足站内金具防晕减噪的要求,提出一种合理的均压环配置方案。针对某500 kV变电站,利用有限元分析软件ANSOFT搭建站内V型绝缘子串及均压环的三维模型,分析不同管径与屏蔽深度的均压环结构对绝缘子串、均压环表面电场强度分布以及对绝缘子串沿轴线电位梯度分布的影响,并根据其影响规律获得合适的配置方案,对均压环结构进行优化。结果表明,均压环结构的优化有效降低了靠近管母线端绝缘子片的承受电压和表面最大场强,也有效改善了绝缘子串的电压和电场强度分布的不均匀性,并能够满足变电站金具防晕减噪的要求。

In order to improve the electromagnetic working environment of substation insulator strings and meet the requirements of anti-corona and noise reduction in the substation, a reasonable grading ring configuration scheme is proposed. A three-dimensional model of 500 kV substation with V-shaped insulator strings and grading ring are established by using the ANSOFT software. The effect of pipe diameter and shielding depth of grading ring on the electric field distribution of insulator strings and grading ring are studied as well as it on the voltage distribution along the axis of insulator string. On this basis, an optimized configuration scheme of grading ring is proposed. It is shown that the optimized grading ring can effectively reduce the potential and the maximum field intensity of insulator near the tubular busbar. The non-uniformity of voltage and electric field distribution of insulator string are improved by the proposed scheme to meet the requirements of anti-corona and noise conduction.