摘要
电子式电压互感器的暂态特性直接决定其在投入电网后能否稳定运行,基于电容分压的电子式电压互感（ECVT）暂态过程主要与电容分压器及负载相关。从理论上分析了电容分压器二次负载电阻及电容器内阻对ECVT暂态特性的影响;对220k V ECVT进行建模,仿真分析了二次负载电阻和电容器串联内阻对短路及重合闸暂态过程的影响,对不同的系统重合闸动作时限给出了相应的二次负载电阻值的最佳取值范围,找出了电容器串联内阻对暂态特性影响的规律。仿真结果表明,对所研制的ECVT,二次负载电阻取300-500kΩ为最佳,高、低压侧电容器串联内阻之比是分压比为最佳。本文的实验结果显示,合理选择电容器和二次负载电阻可以改善暂态特性。
When an electronic voltage transformer is put into the power system,whether it works stably depends on its transient behavior,the transient process of the electronic voltage transformerbased on capacitive（ECVT） voltage is mainly related to capacitive voltage divider and the part connected to it.The influence of the capacitive voltage divider＇s load resistance and internal resistance for ECVT is analysed in theory.A simulation model is built for a 220 kV ECVT to simulate the influence of the capacitive voltage divider＇s load resistance and internal resistance in short-circuit and reclosing transient,and the best range of load resistance for different reclosing time is given,the law of capacitor internal resistance＇s impact on transient characteristics is found out.Simulation results show that for the researched ECVT,the load resistance takes300-500kΩ as the best,the high-low capacitor series resistance ratio is best to be equal to the voltage ratio.This paper＇s experimental data shows that selecting capacitor and load resistance reasonably can improve the transient characteristics.
出处
《电气工程学报》
2015年第10期37-43,共7页
Journal of Electrical Engineering
关键词
电子式电压互感器
短路
重合闸
暂态过程
电容分压器
Electronic voltage transformer
short-circuit
reclosing
transient process
capacitor voltage divider
