克服电容式电压互感器暂态超越的新方法  

A New Method for Overcoming the Transient Overreach of a Capacitive Voltage Transformer

作　　者：温荣[1] 杨波[2] 

机构地区：[1]广西电网公司柳州供电局,广西柳州545005 [2]广西电力职业技术学院,广西南宁530007

出　　处：《电气开关》2011年第2期24-28,共5页Electric Switchgear

摘　　要：为克服高压电网中普遍使用的电容式电压互感器(CVT)的暂态过程引起的故障二次电压的测量误差,从而导致距离保护的超越,在分析了故障时CVT的二次电压信号特点及传统的微机保护算法的缺陷,提出一种改进全波与改进半波傅氏算法相配合的新方法;该方法区别与其他方法不需知道CVT的内部参数,不需牺牲保护的速动性,运算速度快,有效滤除CVT二次信号的非周期分量;通过大量RTDS仿真结果表明,该方法能够在短时间内判断故障区域,将新方法与传统保护算法相比较,论证了新方法的可行性与正确性。The transient error of CVT（Capacitive Voltage Transformer） usually causes the overreach of distance relay in high voltage power system.So many researchers have emphasized their work on this issue for preventing transient overreach.This paper analyses the transient voltage component of CVT and the disadvantage of traditional microprocessor-based protection.A new method based on improved Fourier algorithm with the window of full-cycle and half-cycle is presented.Compared with the traditional algorithm,no parameter of CVT is needed in the whole process.The new method has the higher speed of operation and the better performance of filtering decaying DC components.Finally,digital simulation gives the effect of the new method compared to traditional algorithm where the trip signal output by RTDS,which demonstrates the rationality and reliability of this method.

关 键 词：电容式电压互感器(CVT) 暂态超越 傅氏算法 非周期分量 实时数字仿真(RTDS) 

分 类 号：TM451[电气工程—电器]