35kVSVC装置晶闸管阀高压试验中局部放电问题的分析-电测与仪表.DOCVIP

35kV SVC装置TSC型晶闸管阀高压试验局放问题的分析与处理* 张雷1胡飞2王珊丹1常忠1 （1.中电普瑞科技有限公司，北京 102200；2. 凯兆电力科技有限公司，南京 210000） 摘要：晶闸管阀作为SVC装置中的核心部件，根据相关IEC标准和电力行业标准规定，在出厂前必须进行一系列的高压绝缘试验，来验证其耐受电压能力和局部放电的起止电压是否满足要求。由于35kV电压等级的晶闸管阀工作电压等级高，结构形式和绝缘材料的多样性，导致晶闸管阀在规定试验电压下局放值超过规定允许值的问题时常发生。如果局部放电问题未能得到有效处理，对产品的运行使用将带来严重的绝缘隐患。针对上述情况，本文通过研究新型35kV SVC用TSC型晶闸管阀在高压试验中遇到的典型局部放电问题，提出了相应的分析方法和解决方案：通过试验判断局部放电超标部位，理论分析局放起因主要由于电气结构不合理，导致空气间隙小或存在悬浮电位。通过改进电气结构和等电位处理，局部放电值满足试验要求。本文介绍的方法快速有效，对大功率电力电子器件应用的相关试验有一定的借鉴作用。 关键词：SVC；TSC型晶闸管阀；局部放电；空气间隙；悬浮电位 中图分类号：TM855 文献识别码：B 文章编号：1001-1390（2014）00-0000-00 Analysis and Treatment of Partial Discharge in High Voltage Test for Thyristor Valve with 35kV SVC Device ZHANG Lei1, HU Fei2, WANG Shan-dan1, CHANG Zhong1 (1.China EPRI Science Technology Co., Ltd. , Beijing 102200, China. 2. Kai Zhao Power Technology Co., Ltd., Nanjing 210000, China) Abstract: The thyristor valve is used As the core component of Static Var Compensator (SVC), the thyristor valve should be carried through a series of insulation tests to verify if the withstand voltage and partial discharge start voltage will meet the requirements according to the relevant IEC standards and the standards of the power industry regulation and the need of the project. Because of the high voltage grade of 35kV thyristor valve, the various structures and insulating materials will cause the problem always happen that the partial discharge of thyristor valve in regular test voltage exceeds the permitted value. If the partial discharge problems are not handled effectively, the product operation will bring severe hidden trouble of insulation. In view of the above situation, the typical partial discharge problems in high voltage test with a new TSC thyristor valve with 35kV SVC device are studied in this paper. The corresponding analysis method and solution strategy are proposed, which indicate that the unreasonable electrical structure is the main reason for partial discharge by judging the exceed part t