不同容量下并网模式交流微电网短路故障早期检测与区域定位  

Early Detection and Regional Location of Short Circuit Fault for Grid-connected AC Microgrid With Different Capacity

作　　者：郑昕[1] 甘鸿浩 ZHENG Xin;GAN Honghao(Engineering Research Center of Smart Distribution Grid Equipment(College of Electrical Engineering and Automation,Fuzhou University),Fuzhou 350108,Fujian Province,China)

机构地区：[1]智能配电网装备福建省高校工程研究中心(福州大学电气工程与自动化学院),福建省福州市350108

出　　处：《中国电机工程学报》2024年第11期4353-4366,I0014,共15页Proceedings of the CSEE

基　　金：国家自然科学基金项目(52277136);福建省工业引导性项目(2021H0014)。

摘　　要：随着分布式电源(distributed generation,DG)的容量变化,微电网原有的供电结构发生改变,使得潮流大小、方向和功率结构发生变化,对快速检测和定位微电网中的短路故障区域提出了挑战。在MATLAB/Simulink中搭建低压交流微电网模型;通过高尺度小波能量谱算法对微电网与大电网公共连接点(point of common coupling,PCC)处检测到的电流进行分解,提取适应不同容量情况的短路故障特征值,实现了不同容量下微电网短路故障的早期检测;利用小波能量谱特征结合基于正交最小二乘法(orthogonal least square,OLS)的径向基函数(radial basis function,RBF)神经网络算法提出一种适用于不同容量微电网的短路故障区域定位方法,并进行仿真验证;在此基础上设计并网模式微电网短路故障保护硬件系统,并进行实验验证。结果表明,所设计的保护系统能够快速、准确地同时实现并网模式下交流微电网短路故障的早期检测与区域定位。With the capacity change of distributed generation,the original power supply structure of microgrid has undergone modifications,altering the size,direction,and power flow configuration.This transformation poses a challenge in swiftly detecting and pinpointing the area of short-circuit faults within the microgrid..In this paper,a low-voltage AC microgrid model is built in MATLAB/Simulink.The current detected at the common connection point(PCC)between microgrid and large power grid is decomposed by high-scale wavelet energy spectrum algorithm,and the short-circuit fault eigenvalues suitable for different capacities are extracted,which realizes the early detection of short-circuit fault in microgrid under different capacities.By using wavelet energy spectrum characteristics and orthogonal least square(OLS)-radial basis function(RBF)neural network algorithm,a short-circuit fault location method suitable for microgrids with different capacities is proposed and verified by simulation.On this basis,the short-circuit fault protection hardware system of microgrid in grid connection mode is designed and verified by experiments.The results show that the designed protection system can quickly and accurately realize the early detection and regional location of short-circuit faults in grid-connected AC microgrid at the same time.

关 键 词：并网模式微电网 短路故障 小波能量谱 正交最小二乘法(OLS) 径向基函数(RBF) 早期检测 区域定位 

分 类 号：TM721.2[电气工程—电力系统及自动化] TM713