基于零序PT二次侧注入信号的配电网电容电流测量新方法  

A new method of distribution network capacitive current measurement based on injecting signals into the secondary side of the zero sequence PT

作　　者：宋晓燕[1] 孙岩洲[1] 宋紫嫣 梁京 

机构地区：[1]河南理工大学电气工程与自动化学院,河南焦作454000 [2]河南省电力公司濮阳供电公司,河南濮阳457000 [3]煤炭工业郑州设计研究院股份有限公司,河南郑州450000

出　　处：《电力系统保护与控制》2014年第19期134-138,共5页Power System Protection and Control

基　　金：国家自然科学基金资助(U1204506)~~

摘　　要：在相量法的基础上,为了解决其测量系统对地电容范围小和频率组合选取困难的问题,改进了测量配电网电容电流的方法,并给出了新方法的频率选取和误差分析。改进后的方法提出在PT开口三角侧分别注入一个高频和一个低频的幅值恒定的电压信号,并测量开口三角侧的零序电流。根据等效电路,计算出配电网对地电容。理论分析和仿真试验表明:改进后的测量方法具有计算简便、测量精度高,同样适用于测量较大系统的对地电容等特点,使得中压配电网电容电流的测量更加准确、快捷。In order to solve the problems that the scope of the measurement range of capacitance is limited and to select the proper frequency is difficult, based on the phasor method, a novel method is proposed and the frequency selection and error analyses are given as well. In the improved method, a high and a low frequency amplitude constant voltage signals are injected into PT open delta side, and the zero sequence current of the open the triangle side is measured. According to the equivalent circuit of the distribution network, the capacitance is calculated. Through theoretical analysis and simulation verification, the improved method has the advantages of simple operation and high measuring precision, and is suitable for the capacitance measurement of larger systems.

关 键 词：对地电容 配电网 相量法 电容电流测量 频率 

分 类 号：TM933.1[电气工程—电力电子与电力传动]