
2010年第4卷第5期 2010,Vol.4, No.5
南方电网技术
SOUTHERNPOWERSYSTEMTECHNOLOGY
文章编号:1674-0629(2010)05-0032-04
特高压输电工程
UHV Transmission Engineering
中图分类号:TM422;O657.71
文献标志码:A
云广±800kV直流输电工程换流变压器
油中产气现象分析
赵林杰',黎小林1,饶宏1,朱功辉1,宋述波2
(1.南方电网科学研究院,广州510080;2.中国南方电网超高压输电公司广州局,广州510405)
摘要:云广直流工程极II单极投适后,稳东站3台HY型800kV换流变压器的主油箱油中先后出现微量CH等特征气体。针对这一现象进行分新,认为上述油中产气的可能原因为:OLTC切换经过中间档位时,极性转换开关动作过程中其触头间发生悬浮电位放电导致C,H,等特征气体产生。从OLTC机理上需这种情流不可避免,只要产气现象不楚严重,换流变压器可安全运行。但这种产气现象可能会对于发现换流变压器油溶解气体的真实故障造成障碍,此,有必要对换流变压器油的进行长期色谱限降分析。
关键词:直流输电;特高压;换流变压器;有载调压开关;油中溶解气体分析
AnalysisontheGas-ProducingPhenomenainConverterTransformer'sOil
ofYunnan-Guandong±8ookVDCTransmissionProject
ZHAO Linjie', Li Xiaolin', RAO Hong', ZHU Gonghui', SONG Shubo
(1. Electrical Power Research Institute, CSG, Guangzhou 510080, China;
2. Guangzhou Bureau, CSG EHV Power Transmission Company, Guangzhou 510405, China)
ee ea eadoe ea gases, such as C,H, were detected in the main tank oil of three HY-type 800 kV converter transformers in Suidong Station. This paper analyzes the gas-producing phenomena, and it is concluded that the phenomena may be due to the on-load tap changer (OLTC) operation in which the OLTC's polarity change-over selector action producing discharge of suspending eletric potential leads to production of characteristic gases, such as C2H2- This is inevitably according to the mechanism of OLTC, and the converter transformers will be in safety unless the phenomena becomes more and more serious. However, it is necessary to performen long-term DGA monitoring to the converter transformer oil as the inevitable phenomena could be a hindrance to discovering real faults of transformer oil dissolving gases.
Key words: HVDC; ultro-high voltage; converter transformer; on-load tap changer (OLTC); dissolved gas analysis (DGA)
云广特高压直流工程换流变压器共分为±800 kV高端Y/Y接(即HY型)、±600kV高端Y/△ 接(HD型)、±400kV低端Y/Y接(即LY型)和 ±200kV低端Y/△接(LD型)4种类型。其中, HY型换流变压器技术难度最大,所涵盖的核心技术包括[1-6];
3.5m运输限界和±800kV电压作用下的
绕组绝缘结构设计:
外置式阀侧引线出线装置技术;一真空型有载调压开关的应用: ±800kV阀侧套管技术;
万方数据
大容量和复杂器身结构下漏磁分布、杂散
损耗以及局部过热的控制;
高效变频静音节能冷却器的应用;土800kV换流变压器抗短路设计;
高强度紧漆型油箱结构:精确的工艺制造要求;
±800kV换流变压器试验技术和装备。
2009年12月28日,云产直流工程成功实现极 Ⅱ单极投产。投产后的云广±800kV直流输电系统总体运行良好,但也出现了一些有可能影响系统安全运行的现象。例如,表1所示为穗东站极Ⅱ的3