CVT附加相差对容性设备介损在线监测的影响  

Effect of CVT Additional Phase Error on On-Line Monitoring of Dielectric Loss Factor for Capacitive Equipment

作　　者：李璿[1] 余春雨[1] 王晓琪[1] 吴士普[1] 冯宇[1] 

机构地区：[1]中国电力科学研究院,武汉430074

出　　处：《电测与仪表》2013年第11期10-13,共4页Electrical Measurement & Instrumentation

摘　　要：电容式电压互感器(CVT)在我国变电站中广泛应用,并作为电容型高压设备介质损耗因数在线监测的电压参考信号。研究表明,电压参考信号相位误差对介质损耗因数测量结果造成影响。本文对电容式电压互感器附加误差进行分析,并通过试验得出电网频率及环境温度对CVT相位误差的影响量,结果表明,由于电网频率和环境温度引起的CVT相位误差变化量与电容型高压设备自身绝缘缺陷引起的介质损耗角变化量在同一个数量级,极容易引起电容型高压设备绝缘状态的误判。应开展CVT误差在线校准相关研究,为电容型高压设备介质损耗因数在线监测提供高精度参考电压。Capacitor voltage transformer （CVT） has been widely used in electrical power system for its high dielectric strength and low cost, and is also used to supply voltage reference signal in on-line monitoring of dielectric loss factor for capacitive equipment. Research indicates that phase error of CVT can affect measurement results of dielectric loss. In this paper, the additional phase error of CVT is analyzed, and the influence quantity of CVT phase error caused by power system frequency and ambient temperature is tested. Results indicate that the influence quantity of additional phase error is of the same magnitude as the dielectric loss angle caused by insulation defect of capacitive high-voltage apparatus, therefore is easy to cause the misjudgment of capacitive high-voltage insulation status. Research on on-line calibration of CVT error should be done to improve the precision of reference signal voltage, which is helpful for on-line monitoring of dielectric loss factor for capacitive equipment.

关 键 词：电容式电压互感器 容性设备 在线监测 误差 介损 

分 类 号：TM935[电气工程—电力电子与电力传动]