基于电流极性分布的光伏直流送出线快速保护方法  

PHOTOVOLTAIC DC TRANSMISSION LINE FAST PROTECTION METHOD BASED ON CURRENT POLARITY DISTRIBUTION

作　　者：马健 刘源 张鑫宇 南东亮 董雪涛 赵启 Ma Jian;Liu Yuan;Zhang Xinyu;Nan Dongliang;Dong Xuetao;Zhao Qi(Electric Power Research Institute of State Grid Xinjiang Electric Power Co.,Ltd.,Urumqi 830011,China;Xinjiang Key Laboratory of Whole Process Simulation for Power System,Urumqi 830011,China;State Grid Chongqing Tongnan Power Supply Company,Chongqing 402660,China;School of Electrical Engineering,Xinjiang University,Urumqi 830017,China)

机构地区：[1]国网新疆电力有限公司电力科学研究院,乌鲁木齐830011 [2]新疆电力系统全过程仿真重点实验室,乌鲁木齐830011 [3]国网重庆市电力公司潼南供电分公司,重庆402660 [4]新疆大学电气工程学院,乌鲁木齐830017

出　　处：《太阳能学报》2023年第4期439-447,共9页Acta Energiae Solaris Sinica

基　　金：国网新疆电力有限公司科技项目(5230DK20004U)。

摘　　要：为保障大型光伏电站通过直流升压汇集接入系统的方式安全稳定运行,保护装置需对直流送出线的极间短路故障准确判别。通过分析光伏直流送出线的故障特征,提出一种基于线路两端故障电流极性变化特点的快速保护方法。该方法利用二维映射原理,将线路两端换流器闭锁前的极性特征分布在二维坐标系中,并以概率描述的形式构造保护判据,从而避免极间短路故障存在极性穿越过程时依据瞬时值引起的误判。通过PSIM仿真平台搭建1 MW/±30 kV光伏直流升压外送仿真模型进行验证,结果表明,该方法可快速准确判别故障区段,且具有耐受较高过渡电阻、分布电容、噪声干扰及通信时延的能力。In order to ensure the safe and stable operation of large-scale photovoltaic power stations through DC boost convergence access system,the protection device needs to accurately distinguish the short-circuit fault between the DC transmission lines.By analyzing the fault characteristics of the photovoltaic DC transmission line,a fast protection scheme based on the characteristics of the polarity change of the fault current at both ends of the line is proposed.The method uses the principle of two-dimensional mapping to distribute the polarity characteristics of the converters at both ends of the line before being blocked in the two-dimensional coordinate system,and construct the protection criterion in the form of probability description,so as to avoid the misjudgment caused by the instantaneous value when there is a polarity ride-through process in the short circuit fault between the poles.The 1 MW/± 30 kV photovoltaic DC boost output simulation model is built through the PSIM simulation platform for verification.The results show that this method can quickly and accurately identify the fault section,and has the ability to withstand higher transition resistance,distributed capacitance,noise interference and communication delay.

关 键 词：光伏发电:直流输电 DC-DC变换器 故障区段 二维映射 

分 类 号：TM773[电气工程—电力系统及自动化]