基于虚拟阻抗和锁相环的孤岛检测技术  

An islanding detection based on virtual impedance and phase-locked loop

作　　者：顾一丰 邱稳斌 李艳君[3] 项基[2] GU Yifeng;QIU Wenbin;LI Yanjun;XIANG Ji(State Grid Zhejiang Shaoxing Shangyu Power Supply Company,Shaoxing 312300,China;College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China;School of Information and Electrical Engineering,Zhejiang University City College,Hangzhou 310015,China)

机构地区：[1]国网浙江绍兴上虞区供电公司,浙江绍兴312300 [2]浙江大学电气工程学院,浙江杭州310027 [3]浙江大学城市学院信息与电气工程学院,浙江杭州310015

出　　处：《电力系统保护与控制》2018年第21期78-85,共8页Power System Protection and Control

基　　金：国家重点研发计划项目资助(2018YFB0904800);国家自然科学基金项目资助(61573314);国网浙江省电力公司科技项目资助(5211SX16000J)~~

摘　　要：针对被动孤岛检测存在较大检测盲区,而传统的主动检测法会对电网电能质量造成影响,提出了一种结合锁相环和虚拟阻抗的孤岛检测方法。该方法通过锁相环的输出跟随本地负载谐振频率变化的特性,来对孤岛进行检测。正常并网时,锁相环的输出会稳定在线路频率上;而处于孤岛时,锁相环的输出则会跳变到本地负载的谐振频率处。同时,引入了虚拟阻抗技术对此方法进行了完善,应对频率出现匹配的情况。通过Matlab仿真和RT-LAB半实物仿真平台进行了实验验证,验证了理论推导的正确性及所提孤岛检测方法的有效性。There is a large None Detection Zone(NDZ)for passive islanding detection,and the traditional active detection method will affect the power quality of the power grid.In this paper,a method of islanding detection based on Phase-Locked Loop(PLL)and virtual impedance is proposed.The method uses the output of the PLL to follow the resonant frequency of the local load to detect the islanded condition.When the grid is connected properly,the output of the PLL will stabilize at the line frequency.When it is on the islanded condition,the output of the PLL will jump to the resonant frequency of the local load.At the same time,the technology of the virtual impedance is used to help the method to deal with the frequency matching situation.Both the Matlab simulation and the RT-LAB hardware-in-loop simulation are used to verify the correctness of theoretical derivation and the effectiveness of the proposed island detection method.

关 键 词：分布式系统 锁相环 孤岛 虚拟阻抗 谐振频率 

分 类 号：TM732[电气工程—电力系统及自动化]