1000kV罐式电容式电压互感器附加误差特性研究  

Additional Error Characteristics Study of 1 000 kV Tank-type Capacitor Voltage Transformer

作　　者：李璿[1] 吴士普[1] 王晓琪[1] 贾如[1] 姚涛[1] 

机构地区：[1]中国电力科学研究院,武汉430074

出　　处：《高压电器》2015年第9期17-21,27,共6页High Voltage Apparatus

基　　金：国家电网公司科技项目(GYW17201400168)~~

摘　　要：1 000 kV罐式CVT是为特高压GIS设备电能计量、电压测量及继电保护提供电压信号的新型结构电压互感器,其电压测量准确度关系到特高压电网电能计量准确性及继电保护的可靠性。1 000 kV罐式CVT与1 000 kV柱式CVT在电容分压器结构上存在很大差异,而电容分压器性能与CVT附加误差密切相关,因此,有必要对1 000 kV罐式CVT附加误差特性进行研究。文中建立了1 000 kV罐式CVT电容分压器物理模型,计算1 000 kV罐式CVT高压电容C1及中压电容C21的电容温度系数,研究1 000 kV罐式CVT温度附加误差计算及分析方法,计算结果表明:由于金属电极热膨胀引起的温度附加误差为-0.256 5′≤δτ≤0.085 5′;由于电容分压比变化引起的温度附加误差为-2.6×10-2≤fτ(%)≤8.87×10-3。文中研究结果为1 000 kV罐式CVT现场长期稳定运行奠定理论基础。1 000 kV tank-type capacitor voltage transformer （CVT） is one kind of capacitor voltage transformer whose capacitor divider has a new configuration. For one kind of equipment used for electric energy metering, voltage-measuring and power system protecting of UHV GIS, the accuracy of voltage testing relates to the accuracy of electric energy metering and the reliability of relay protecting. The configuration of the capacitor dividers between 1 000 kV tank-type CVT and 1000 kV column-type capacitor voltage transformer （column-type CVT） are greatly different, this difference affects the additional error of 1000 kV tank-type CVT. In order to study its additional error, this paper establishes the physical model of capacitor divider of tank-type CVT, studies the capacitor divider＇s temperature characteristic in which electrode has a structure of coaxial circular and SF6 gas is used in it as dielectric medium, analyzes the capacitor temperature coefficient of high voltage capacitor C1 and intermediate voltage capacitor C21. Besides, a calculating and analyzing method of temperature additional error of 1000 kV tank-type CVT is studied. The calculated results indicate that the temperature additional error which caused by thermal expansion of metal electrode is -0.256 5＇≤δτ≤0.085 5′, the temperature additional error caused by capacitive divider ratio changes is -2.6×10-2≤fτ（%）≤8.87×10-3. The research result of this paper lays a foundation of field long-term stable operation of 1 000 kV tank-type CVT.

关 键 词：罐式 电容式电压互感器 温度附加误差 电容温度系数 

分 类 号：TM451[电气工程—电器]