±500kV直流电压互感器现场校准技术试验分析  

Experimental Analysis of the On-site Calibration Technology for ±500 kV DCPTs

作　　者：李前[1,2] 章述汉[1] 李登云[1] 李鹤[1] 胡浩亮[1] 

机构地区：[1]国网电力科学研究院,武汉430074 [2]华中科技大学电气与电子工程学院,武汉430074

出　　处：《高电压技术》2010年第11期2856-2862,共7页High Voltage Engineering

基　　金：国家电网公司科技项目(SG0880)~~

摘　　要：直流电压互感器是测量直流输电系统电压的重要设备,其测量性能的准确关系到直流输电系统的安全稳定运行。为此,研制了高准确度标准分压器,依照检定规程,在额定电压下对德阳换流站极线I上的直流电压互感器进行了现场校准试验,对试验数据进行分析研究得到以下结果：①直流电压互感器的零点影响准确度,必须进行零点修正;②进行零点修正后,仍不满足0.2级要求：由接口柜A中CH3通道输出信号得到的相对误差在0.81%-0.98%,线性为0.17%;由接口柜B中CH3通道输出信号得到的相对误差在0.80%-1.21%,线性为0.41%;③直流电压互感器存在较大变差：由接口柜A中CH3通道输出信号得到的相对误差在30 kV时的变差最大,为0.1%;由接口柜B中CH3通道输出信号得到的相对误差在5 kV时的变差最大,为0.41%。分析结果表明,被测直流电压互感器的准确度不满足设计要求,对直流电压互感器进行安装前的现场校准和安装后的周期性校准是十分必要的。DCPT is important equipment for DC voltage measurement in HVDC transmission system.A standard divider with high accurate scale factor was developed,and an on-site calibration test at rated voltage for the DCPT at pole bus I in Deyang converter station was performed in accordance with the verification regulation of DC high voltage dividers.The test results were analyzed,and it is revealed that：（a） it is necessary to correct the zero point offset of DCPT because the scale factor accuracy is affected obviously by the offset;（b） the relative error of the scale factor can not meet the demands of 0.2 class even after offset correction： the relative error of the scale factor obtained from CH3 in interface cabinet A is 0.81%-0.98%,the linearity is 0.17%,and the relative error of the scale factor obtained from CH3 in interface cabinet B is 0.80%-1.21%,the linearity is 0.41%;（c） there are large variations in the test results of the scale factor： the highest variation of the scale factor obtained from CH3 in interface cabinet A is 0.1% at 30 kV,and the highest variation of the scale factor obtained from CH3 in interface cabinet B is 0.41% at 5 kV.The results show that the accuracy of DCPTs can not meet the design requirements,it is necessary to periodically perform the on-site calibration tests for DCPTs before the installment and after the installment.

关 键 词：直流电压互感器 校准试验 标准分压器 现场 零点修正 相对误差 变差 

分 类 号：TM451[电气工程—电器]