基于电流相位的多端口光伏直流汇集系统故障区段辨识方法  

Fault Zone Identification Method for Multi-port Photovoltaic DC Collection System Based on Current Phase

作　　者：和敬涵[1] 陈想 李猛 杜晓通 闫诗琪 HE Jinghan;CHEN Xiang;LI Meng;DU Xiaotong;YAN Shiqi(School of Electrical Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学电气工程学院,北京100044

出　　处：《高电压技术》2025年第2期520-529,共10页High Voltage Engineering

基　　金：国家自然科学基金(U23B6007)。

摘　　要：多端口光伏直流升压汇集并网系统分支多、线路短,故障发展快、电流峰值高,故障区段的快速可靠辨识困难。为实现系统的快速故障隔离与恢复,提出了一种基于高频电流相对相位的极间故障区段辨识方法。首先,构建不同区段故障后的暂态等效网络,并利用换流器出口等效并联电容与限流电感的串联谐振条件简化等效网络,得到高频电流间的相关性特征。然后,将相关性定量为相位差分布表征,并利用汇集支路与送出线间特定频段电流的相位差分布差异构建故障区段辨识判据,辨识结果采用逻辑量形式输出。最后,通过仿真对所提方法的有效性进行了验证。仿真结果表明:该方法最快能在故障后2 ms内可靠选线,有较强的抗噪性和耐过渡电阻、分布电容能力,方法简单实用,具有一定的工程应用价值。A multi-port PV DC boost collection grid-connected system has many branches,short lines,fast fault devel-opment and high current peak,and it is difficult to identify the fault section quickly and reliably.In order to realize rapid fault isolation and recovery of the system,an inter-electrode fault segment identification method based on the relative phase of high frequency current is proposed.Firstly,the transient equivalent network is constructed after faults in different segments,the equivalent parallel capacitor and current limiting inductor are used to simplify the equivalent network,and the correlation characteristics between high frequency currents are obtained.Then,the correlation is quantified as phase difference distribution,and the fault section identification criterion is constructed based on the phase difference distribu-tion between the collector branch and the sending line.The identification result is output in the form of logical quantity.Finally,the simulation results show that the method can be adopted to reliably select the line within 2ms after the fault at the earliest,and has strong resistance to noise,transition resistance,and distributed capacitance.The method is simple and practical,and has a certain engineering application value.

关 键 词：直流并网 相关性 相对相位 故障分析 大型光伏电站 故障区段辨识 

分 类 号：TM615[电气工程—电力系统及自动化]