基于注意力机制的光伏系统故障电弧检测与定位研究  

Research on Arc Fault Detection and Location in Photovoltaic Systems Based on Attention Mechanism

作　　者：杨淇 孟羽 陈思磊 武涵聪 杨晓华 李兴文[1] YANG Qi;MENG Yu;CHEN Silei;WU Hancong;YANG Xiaohua;LI Xingwen(State Key Laboratory of Electrical Insulation and Power Equipment(Xi’an Jiaotong University),Xi’an 710049,Shaanxi Province,China;School of Electrical Engineering,Xi’an University of Technology,Xi’an 710048,Shaanxi Province,China;Electric Power Research Institute,Yunnan Power Grid Co.,Ltd.,Kunming 650051,Yunnan Province,China)

机构地区：[1]电工材料电气绝缘全国重点实验室(西安交通大学),陕西省西安市710049 [2]西安理工大学电气工程学院,陕西省西安市710048 [3]云南电网有限责任公司电力科学研究院,云南省昆明市650051

出　　处：《中国电机工程学报》2024年第19期7840-7851,I0030,共13页PROCEEDINGS OF THE CHINESE SOCIETY FOR ELECTRICAL ENGINEERING

基　　金：国家自然科学基金项目(52107168);陕西省科技计划项目(2022TD-59);中国南方电网云南电网有限责任公司科技项目(YNKJXM20222147)。

摘　　要：由于绝缘损坏等原因产生的串联故障电弧严重威胁着光伏系统的安全稳定运行。同时,光伏系统中阻抗网络会影响检测故障电弧的能力,降低时频检测方法的可靠性。针对阻抗网络带来了故障电弧检测与定位困难的问题,文中搭建含光伏阻抗网络模块的直流故障电弧实验平台,开展不同电流等级、不同负载、不同线路模拟长度的故障电弧实验。通过傅里叶变换频谱和小波变换分析电流信号,构建幅值比、提升比指标,定量评估光伏阻抗网络前后的故障电弧特征差异,分析光伏阻抗网络对故障电弧特征的弱化影响,并对小波重构信号做三点对称差分能量算子处理,使100 k Hz内各频段特征得到增强,有效改善了故障电弧检测。根据特征随线路增长而衰减的规律,提出基于长短期记忆网络和注意力机制的故障电弧检测与定位算法,实现了0~80 m的串联故障电弧定位,最大误差不超过4 m。研究可为光伏系统故障电弧检测模块的设计提供一定理论和方法基础。The series arc fault caused by insulation damage and other reasons may threaten the stable operation of photovoltaic systems seriously.Meanwhile,the ability of arc fault detection may be affected by the impedance network in photovoltaic systems,and the reliability of time-frequency detection methods is reduced.To address the challenge of detecting and locating arc fault caused by impedance networks,this paper establishes a DC arc fault experimental platform with photovoltaic impedance network module.The arc fault experiments with different current levels,loads,and simulated lengths of lines are conducted.The current signal is analyzed through fast Fourier transform(FFT)spectrum and wavelet transform.The amplitude ratio and lift ratio indicators are constructed to evaluate the difference of arc fault feature before and after the photovoltaic impedance network.The weakening effect of photovoltaic impedance network on arc fault feature is analyzed.The three-point symmetric differential energy operator(DEO3S)is applied to the wavelet reconstruction signal to enhance the feature of each frequency band within 100 kHz that the arc fault detection is effectively improved.The arc fault detection and location algorithm based on Long Short-term Memory network with Attention mechanism is proposed according to the law of attenuation of feature with the line grows.The location of series arc fault within 0~80 m is achieved with a maximum error of no more than 4m.It may provide crucial theoretical and technical references for developing arc fault detection modules in photovoltaic systems.

关 键 词：光伏系统 故障电弧 三点对称差分能量算子 注意力机制 故障定位 

分 类 号：TM501[电气工程—电器]