一种间接测量电压互感器二次回路电压降的方法

通过研究电压互感器（voltage transformer,VT）二次回路电压降的主要来源,分析 VT二次回路阻抗的构成和运行特性,发现接触电阻是导致 VT二次回路电压降变化的主要原因。当计量电压二次回路阻抗为确定值时,VT二次负荷和 VT二次回路压降存在着对应的关系,可以通过测量二次负荷值来了解二次回路阻抗值,进而推算 VT二次回路压降值。基于此,推导出了用 VT二次负荷计算出 VT二次回路电压降的公式,并提出了通过分析对比 VT二次回路负荷变化大小及趋势,来对 VT二次回路压降开展技术监督的工作方法。

A Method for Indirectly Measuring Voltage Transformer Secondary Circuit Voltage Drop

By means of studying main source of voltage drop of voltage transformer secondary circuit,this paper analyzes constitution and running characteristic of VT secondary circuit and discovers the main reason is contact resistance. When im-pedance of metering voltage secondary circuit was a determined value,there was corresponding relationship between VT sec-ondary load and voltage drop and it was able to learn impedance value of the secondary circuit by measuring secondary load value and calculate voltage drop value of VT secondary circuit. A calculation formula for voltage drop value of VT secondary circuit was deduced by VT secondary load and a working method for developing technical supervision on voltage drop of VT secondary circuit was proposed by analyzing and comparing changes and trends of VT secondary load.