电力系统保护与控制2026，Vol.54Issue(2)：1-12,12.DOI:10.19783/j.cnki.pspc.250231
基于U-I象空间分布的CT饱和识别及畸变电流重构方法
CT saturation identification and distorted current reconstruction method based on U-I image spatial distribution
摘要
Abstract
Current transformers(CTs)are core components of various differential protection,but they are prone to saturation under complex fault current characteristics and significantly increased current amplitudes.First,voltage information provided by potential transformers(PTs)at measurement points is integrated,and a voltage-current coupling relationship is established to plot trajectory curves in a two-dimensional image space,with current on the horizontal axis and voltage on the vertical axis.This approach mitigates the interference of single-signal distortion caused by CT saturation on state identification.Based on the deviation of the degree of trajectory from a standard ellipse,saturation states are identified and the severity of saturation is graded.Finally,sampling points within the linear transmission interval are selected,and an improved ellipse-fitting algorithm is applied to integrate the image space and reconstruct the distortion current.A 220 kV transmission line model with new energy integration is constructed on the PSCAD/EMTDC platform.Simulation results show that the proposed method can efficiently and accurately identify CT saturation and reconstruct secondary distorted currents under different types and severities of CT saturation.关键词
电流互感器/饱和识别/线性传变/椭圆拟合算法/电流重构Key words
current transformer/saturation recognition/linear transmission/ellipse-fitting algorithm/current reconstruction引用本文复制引用
李振兴,张星宇,朱益,翁汉琍,李振华,周吉安..基于U-I象空间分布的CT饱和识别及畸变电流重构方法[J].电力系统保护与控制,2026,54(2):1-12,12.基金项目
This work is supported by the National Natural Science Foundation of China(No.52077120). 国家自然科学基金项目资助(52077120) （No.52077120）
