±800kV直流二联复合绝缘子耐张串均压环参数设计

为了给±800kV直流输电线路复合绝缘子耐张串提供合理的均压环配置方案,采用场域分解的方法将三维无界场域分解成有界子区域,使用有限元方法计算了±800kV直流输电线路二联复合绝缘子耐张串的电场分布,并分别进行了均压环参数优化设计。应用ANSOFT软件建立±800kV直流线路带杆塔、导线、绝缘子耐张串的三维模型,研究了均压环的管径、环径和抬高距对耐张串电场分布的影响规律,基于控制电场强度的考虑得到了均压环结构参数的优化配置方案。有限元计算结果表明,安装了设计的均压环后,复合绝缘子护套、金具、均压环表面最大电场强度均能满足要求。

Design of Grading Rings for ?800 kV DC Tension String with Two Compos-ite Insulators in Parallel

In order to serve reasonable ar-rangement forms of grading rings for the tension com-posite insulator string of ±800 kV DC power trans-mission, and with the domain de-composition method to decom-pose the whole 3D electric field into several limited parts, this paper adopts the finite element method to calculate the elec-tric field distribu-tion around tension string with two composite insula-tors in parallel. A 3D model of ±800 kV DC power transmission con-sisting of tower configuration, bun-dled conductors and tension insulator string is established based on ANSOFT software, and the influence of the ring radius, ring tube radius and the ring position of the grading ring on the string's electric field distribution is researched, result-ing in an optimum scheme for the grading ring struc-ture. The calcula-tion results of the finite element method show that with the designed grading ring in in-stallation, the elec-tric field intensity around the sheath, metal fitting and the grading ring are controlled satisfac-torily.