换流变压器下新型纤维素绝缘纸特性综述  

Review on the Characteristic of New Cellulose Insulation Paper Used in the Converter Transformer

作　　者：廖瑞金[1] 王季宇 袁媛[1] 高飞[2] 李剑[1] 

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆400044 [2]中国电力科学研究院,北京100192

出　　处：《电工技术学报》2016年第10期1-15,共15页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51437001);国家创新研究群体基金(51321063)资助项目

摘　　要：换流变压器是高压直流输电网络的关键设备之一,其阀侧主绝缘由于运行工况电场情况复杂通常具有较高的故障率。虽然通过在线监测及故障诊断技术手段可以提高绝缘可靠性,但若考虑到停电维修所带来维修和输电损失成本,高压直流输电网络运行有效性和经济性并不能得到有效保证。油纸绝缘作为换流变压器阀侧的主要绝缘形式,其绝缘可靠性与换流变压器安全运行紧密相关。其中在阀侧处构成固体绝缘的绝缘纸不仅长期受到热应力作用造成绝缘劣化,同时还承受交直流叠加和极性反转等复杂电场作用,容易积聚空间电荷、承受更多的直流场强分量,并且其在劣化后引起的性能下降是不可逆转的,因此绝缘纸的性能是决定换流变压器运行可靠性的重要因素。为了保障换流变压器安全可靠运行,结合国内外文献及课题组相关研究成果,旨在从提升纤维素绝缘纸的抗热老化性能、耐绝缘击穿特性以及空间电荷分布特性三大方面阐述当前采用改性技术提升绝缘纸性能的研究现状,分析各改性方法的利弊,探究经济可行的纤维素绝缘纸改性方法,从本质上提升换流变压器运行可靠性。Converter transformer is one of the most critical and strategic components in HVDC transmission, and its insulation system of the valve-side winding generally has high failure rate because of complex operation conditions. Although the traditional methods can improve the equipment reliability through on-line monitoring and fault diagnosis techniques, yet it is hard to guarantee the efficiency and economy when the maintenance cost and power transmission loss cost during the outages are taken into account. As the major insulation system in the valve-side winding, oil-paper insulation plays a vital role in the reliability and safety of converter transformer. Wherein, the insulation paper of the insulation system is not only deteriorated by the long-term impact of thermal stress, but also subjected to complex operating conditions such as AC-DC hybrid voltage and polarity reversal. Besides, the insulation paper is considered to be irreversible after degradation. Therefore, it is essential to improve the performance of insulation paper. This paper overviews the overseas and domestic research status combined with the studies of our group, aiming at improving the anti-thermal aging performance, breakdown performance and space charge characteristics of cellulose insulation paper. All the mentioned methods will be analyzed in this paper, and a new cellulose insulation paper used in the converter transformer is investigated.

关 键 词：换流变压器 纤维素绝缘纸 抗热老化性能 耐击穿特性 空间电荷分布特性 

分 类 号：TM215[一般工业技术—材料科学与工程]