800kV直流复合绝缘子短样人工污秽闪络特性研究

±800kV直流复合绝缘子短样人工污秽闪络特性研究

第27卷 第10期 2007年4月 中 国 电 机 工 程 学 报

Proceedings of the CSEE Vol.27 No.10 Apr. 2007

©2007 Chin.Soc.for Elec.Eng.

文章编号：0258-8013 (2007) 10-0014-06 中图分类号：TM835 文献标识码：A 学科分类号：470 40

±800kV直流复合绝缘子短样人工

污秽闪络特性研究

李立浧1，蒋兴良2，孙才新2，张志劲2，胡建林2

(1．中国南方电网有限责任公司，广东省 广州市 510000；

2．重庆大学电气工程学院高电压与电工新技术教育部重点实验室，重庆市 沙坪坝区 400044)

Study on Pollution Flashover Performance of Short Sample of ±800kV

UHV DC Composite Insulators

LI Li-cheng1, JIANG Xing-liang2, SUN Cai-xin2, ZHANG Zhi-jin2, HU Jian-lin2

(1. China Southern Power Grid CO. LTD, Guangzhou 510000, Guangdong Province, China; 2. Key Laboratory of High Voltage and Electrical New Technology of Ministry of Education and College of Electrical Engineering of Chongqing University, Shapingba

District, Chongqing 400044, China) ABSTRACT: There is no design, construction and operating experience of the UHV DC transmission lines both at home and abroad. To meet the demands of the construction of the Yun-Guang ±800kV UHV DC transmission line, the artificial pollution flashover performance (PFP) of the short samples of 5 kinds of UHV/EHV DC composite insulators are investigated. The influences of salt deposit density (SDD) and atmospheric pressure (P) on the PFP of the test insulators are analyzed. The research results show that the a, characterizing the influence of SDD on the flashover voltages (Uf) of the short samples of the DC composite insulators, is related with the configuration and the material of the insulator shed. The a, between 0.25 and 0.3, is smaller than those of porcelain and glass insulators. That is to say, the influence of SDD on the Uf of the DC composite insulators is relatively little. In the severe pollution regions, the composite insulators have certain advantages. The n characterizing the influence of P on the Uf of the DC composite insulators is related with the configuration and the material of the insulator shed and the SDD. The n, between 0.5 and 0.8, is larger than those of porcelain insulators. Therefore, in the high altitude regions, the composite insulators have no advantages. Based on the test results, if insulator sample E is selected for the ±800kV UHV DC transmission line, the basic arc distance should be no less than 8.16m and the creepage distance no less than 30.2m.

基金项目：国家自然科学基金项目(50577070,90210026)。

Project Supported by National Natural Science Foundation of China (50577070,90210026)

KEY WORDS: extra & ultra high voltage; direct current; composite insulator; artificial pollution; flashover performance 摘要：特高压直流输电在国内外均没有设计、建设和运行经验。根据我国云广±800kV特高压直流工程建设的需要，该文以5种不同结构型式的超、特高压直流复合绝缘子短样为试品，在人工雾室试验研究了试品的人工污闪特性，分析了试品绝缘子污闪电压与盐密、气压的关系。结果表明，直流复合绝缘子短样污闪电压(Uf)的污秽程度影响特征指数(a)与伞裙结构和材质有关，其值为0.25~0.3，小于瓷和玻璃绝缘子绝缘子，即Uf受污秽程度的影响较小，在污秽严重地区，复合绝缘子具有优势；Uf的气压影响特征指数n与绝缘子材质、结构、污秽程度等有关，对于直流复合绝缘子，n值为0.5~0.8，大于瓷绝缘子，在高海拔地区，复合绝缘子不具有优势。根据该文试验结果，采用样品绝缘子E，±800kV特高压直流输电线路在轻污秽、海拔1000m及以下地区的基本电弧距离应不小于8.16m，爬电距离应不小于30.2m。 关键词：超/特高压；直流；合成绝缘子；人工污秽；闪络特性

0 引言

云广±800kV特高压直流线路跨越地区的海拔高度部分超过1000m，最高达2700m左右，且面临工业污秽、盐雾污秽和自然灰尘、鸟粪、覆冰(雪)等的影响。因此，输电线路绝缘子面临着多种污秽和高海拔的综合影响。复合绝缘子因其优异的防污性能而成为云广±800kV特高压直流输电线路的主要选择之一。