特高压直流电压互感器换热结构设计及其对误差特性的影响研究  

Research on the heat exchange structure designing for UHV DCVT and its influence on error characteristics

作　　者：汪本进 王睿晗[2] 吴士普 叶子阳 徐思恩 Wang Benjin;Wang Ruihan;Wu Shipu;Ye Ziyang;Xu Sien(Wuhan Branch,China Electric Power Research Institute Co.,Ltd.,Wuhan 430074,China.;State Grid Sichuan Electric Power Company,Chengdu 610064,China)

机构地区：[1]中国电力科学研究院有限公司武汉分院,武汉430074 [2]国网四川省电力公司,成都610064

出　　处：《电测与仪表》2022年第1期84-92,共9页Electrical Measurement & Instrumentation

基　　金：国家电网公司总部科技资助项目(GYW17201800038)。

摘　　要：为解决直流电压互感器(DCVT)电阻温升造成的测量准确度问题,文章对±800 kV DCVT换热问题进行了研究。分析了电阻选择原则,在此基础上进行了DCVT的设计,重点设计了DCVT的换热结构。通过采用涡旋式换热配合双气式结构来达到优化换热方式降低因电阻温升带来的误差的目的。为验证设计效果,建立了考虑SF_(6)物性参数随温度变化的三维DCVT内部温升计算模型。计算结果表明:论文设计的换热器可使DCVT内部总体温升下降10.5%,轴向温差下降43%。因电阻温升产生的测量误差仅为0.025%,符合设计要求。为进一步验证换热效果,进行了温升对分压比影响的试验。试验结果表明:温升条件下DCVT分压比的误差小于0.2级误差限值。理论与试验均表明:论文设计的涡旋式换热结构可使电阻温升导致的误差远小于要求的误差限值,可保证DCVT具有很好的测量精度。In order to solve the measurement accuracy problem caused by the temperature rise of DC voltage transformers(DCVT)resistance,this paper has been studied the heating problem for±800 kV DCVT.The principle of resistance selection is analyzed.On this basis,the DCVT design is performed,and the heat exchange structure of DCVT is designed.Through the adoption of vortex type heat exchanger with double gas type structure is adopted to optimize the heat exchange mode and reduce the error caused by the temperature rise of resistance.To verify the design effect,a three-dimensional DCVT internal temperature rise calculation model is established considering the change of SF_(6) physical parameters with temperature.The calculation results show that the designed heat exchanger can reduce the internal overall temperature rise of the DCVT to 10.5%,and the axial temperature difference is reduced by 43%,and the measurement error generated by the resistance temperature rise is 0.025%,which meets the design requirements.In order to further verify the heat exchange effect,and the test of temperature rise on the voltage division ratio is carried out.Experimental results show that under the condition of temperature rise,DCVT voltage division ratio error is less than 0.2 class error limit.Both theoretical and experimental results show that the vortex heat exchange structure designed in this paper enables that the error caused by resistance temperature rise is much smaller than the required error limit,and ensures the DCVT has good measurement accuracy.

关 键 词：直流电压互感器 涡旋式换热器 轴向温差 分压比误差 

分 类 号：TM451[电气工程—电器]