电子式电压互感器暂态特性仿真与研究

从基于电容分压的电子式电压互感器(ECVT)的工作原理入手,介绍了该互感器的基本构成,着重分析了ECVT的暂态特性,并以单相220 kVECVT的基本特性为建模参数,利用OrCAD仿真其暂态特性并量化了二次分压电阻的阻值范围。仿真结果表明,通过合理选择二次分压电阻,可以修正ECVT的暂态特性,解决了ECVT暂态过程中出现的短路和重合闸问题。实验数据证实,所研制的220 kV ECVT阻值确定在10 MΩ等级暂态特性最佳,达到了测量0.5级和保护3P级准确度设计要求,满足IEC60044-7《电子式电压互感器》标准要求。

Investigation and simulation of transient characteristics of electronic voltage transformer

The basic structure and working principle of ECVT(Electronic Voltage Transformer based on Capacitive voltage divider) are presented.Its transient characteristics are analyzed and the basic characteristic of single-phase 220 kV ECVT is taken as the modeling parameter.OrCAD software is used to simulate its transient response and quantify its range of resistance.Simulative result indicates that the short circuit and reclose problem occurred during the transition process of ECVT can be solved by properly setting the voltage divider resistance.Experimental data confirms that,the transient characteristics of 220 kV ECVT are the best when the resistance is set at 10 MΩ class,which,according to IEC60044-7,meets the design requirements for measuring accuracy of 0.5 class and for protection accuracy of grade 3P.