±800kV天—中直流对哈密电网变压器直流偏磁影响的仿真和实测研究  

Investigating the Impacts of ±800 k V Tian-Zhong HVDC Project on Transformer DC Magnetic Bias in Hami Power Grid via Simulation and Measurement

作　　者：王建[1] 马勤勇[1] 常喜强[2] 

机构地区：[1]国网新疆电力公司电力科学研究院,乌鲁木齐830011 [2]国网新疆电力公司,乌鲁木齐830063

出　　处：《高压电器》2015年第11期168-175,共8页High Voltage Apparatus

摘　　要：±800 k V天—中特高压直流工程于2013年投运,天山换流站地处哈密电网变电站集中地带,其接地极位置较为特殊,为研究天中直流在单极大地方式运行时对哈密电网变压器直流偏磁的影响,通过交流电网直流电流分布计算软件仿真计算分析了哈密电网变压器直流分布的情况,同时在系统高端调试期间对换流站所在的哈密地区电网直流偏磁进行了多点测量,积累了大量实测数据。仿真结果表明,在天中直流大功率单极大地运行时,离天山换流站较近的220 k V中性点接地变压器中性点直流电流较大,实测也发现与仿真类似的结果,仿真结果与实测数据基本相符合,严重威胁主变偏磁运行,后期通过在直流电流过大的主变加装了直流偏磁抑制装置,实测表明其大大降低了变压器中性点的偏磁电流,提高了哈密地区电网的安全性和可靠性。The ±800 kV Tian-Zhong HVDC project was put into operation in 2013, and its Tianshan converterstation is located in the centralized substation area of Hami electric grid, where grounding pole location is ratherspecial. To investigate the impacts of the ±800 kV Tian-Zhong HVDC project on transformer DC magnetic bias inHami power grid, the calculation software of AC power grid DC current distribution was employed to analyze theDC current distribution of the transformer in Hami power grid by means of simulation. And the multi-pointmeasurement of the transformer DC magnetic bias in Hami power grid, where the Tianshan DC converter station islocated in, was conducted. Simulation shows that when the Tian-Zhong HVDC project operated with high power inmonopole earth mode, the DC current at the neutral point of the neutral-grounded 220 V transformer nearer to theTianshan DC converter station got larger. The simulation results coincide with the measured ones. This situationharms the safe operation of the main transformer with magnetic bias current. Subsequently, a DC magnetic biassuppression device was added to the main transformer with large neutral DC current, hence the DC magnetic biascurrent was greatly reduced.

关 键 词：天中直流 变压器 直流偏磁 仿真与实测 偏磁抑制 

分 类 号：TM721.1[电气工程—电力系统及自动化]