电容分压型电子电压互感器的特性研究  

Characteristics of electronic voltage transformers based on capacitive voltage divider

作　　者：杨玲君[1] 周冬旭[1] 徐志超[1] 

机构地区：[1]武汉大学电气工程学院,湖北武汉430072

出　　处：《电力自动化设备》2012年第8期71-74,共4页Electric Power Automation Equipment

基　　金：江苏省电力公司科技项目(J20100009)`~~

摘　　要：分析和建立电容分压型电子电压互感器(EVT)的传递函数模型,重点分析了EVT的频率特性和滞留电荷的暂态特性,建立了滞留电荷暂态数学模型,对影响频率特性和暂态特性的参数进行了数学分析。仿真分析表明EVT的频率特性和暂态响应过程与高、低压电容和积分器参数有关。可知:减小积分电容或减小积分反馈电阻时可减小频带宽度;减小采样电阻或高压臂电容可增加频带宽度;减小低压电容或采样电阻可缩短滞留电荷造成的暂态过程,减小暂态误差。The transfer function model of EVT（Electronic Voltage Transformer based on capacitive voltage divider） is analyzed and deduced. Its frequency characteristics and the transient characteristics of its trapped charge are analyzed. The transient mathematical model of trapped charge is deduced and the parameters which have influences on frequency characteristics and transient characteristics are analyzed mathematically. Simulative results show that,the capacitors of voltage divider and the parameters of integrator have great effects on the frequency characteristics and transient characteristics of EVT. Reducing the integral capacitor or integral feedback resistor may reduce its bandwidth. Reducing the sampling resistor or high-voltage capacitor may increase its bandwidth. Reducing the low-voltage capacitor or sampling resistor may shorten the transient process caused by the trapped charge and then reduce the transient error.

关 键 词：EVT 频率特性 暂态分析 滞留电荷 传递函数 数学模型 

分 类 号：TM93[电气工程—电力电子与电力传动] TM452