换流变压器冷却系统电源自动切换回路分析

Analysis of Automatic Power Switching Loop of Converter Transformer Cooling System

换流变压器冷却系统由若干组冷却器组成,各组冷却器要能够循环备用,以保证换流变压器安全运行。对南方电网4条高压直流输电线路的换流变压器冷却系统电源自动切换回路进行了分析,结果显示:云广直流系统的最为完善,其余3条的均有不足。天广直流系统的换流变压器冷却系统两路电源不能够手动切换,贵广Ⅰ回、贵广Ⅱ回直流系统的换流变压器冷却系统电源自动切换回路设计未考虑继电器粘连情况。

Converter transformer cooling system consists of several revolving cooling groups in order to ensure the safe operation of the converter transformer.Analysis on the automatic power switching loop of converter transformer cooling system in four HVDC projects in China Southern Power Grid is carried out in this paper.It is found that the automatic power switching loop of converter cooling system in Yunnan-Guangdong HVDC projrcts has the most comprehensive design,and the remaining three are inadequate.The redudant power of converter cooling system in Tianshengqiao-Guangzhou HVDC projects can not be switched manually.In the design of the power automatic switching circuit of converter cooling system in Guizhou-Guangdong line I II HVDC projects,the situation of relay contact adhesion was not considered.