基于2种傅氏算法相关性分析的变压器励磁涌流识别方法

针对励磁涌流波形畸变严重且会出现尖顶波,而故障电流基本保持基频正弦波特征的特点,提出一种识别变压器励磁涌流的新方法。先通过全波傅氏算法和半波傅氏算法分别求得差动电流的基波虚部,利用相关分析原理求得归一化后的相关系数,设定整定值来判断励磁涌流。通过动模实验对变压器在空载合闸、相间短路、单相接地短路以及带故障空投4种运行状态下获得的数据进行分析,验证了所提方法的正确性和有效性。

Identification of transformer excitation inrush based on correlation analysis between two Fourier algorithms

As the excitation inrush is seriously distorted while the fault current is nearly sinusoid,a method is proposed to identify the excitation inrush current of transformer.Full-wave Fourier algorithm and half-wave Fourier algorithm are used to respectively calculate the imaginary part of fundamental differential current,and the normalized correlation coefficient between them is then deduced by correlation analysis,which is compared with a setting to identify the inrush current.Dynamic tests are carried out for...