基于无功扰动的分布式电源孤岛运行检测方法研究  

Research on Islanding Operation Detection Method for Distributed Generation Based on Reactive Power Disturbance

作　　者：于雷 宁骁 YU Lei;NING Xiao(DC Division,State Grid Hubei Electric Power Company,Yichang 443000,Hubei Province,China;Xiaogan Power Supply Company,State Grid Hubei Electric Power Company,Xiaogan 432099,Hubei Province,China)

机构地区：[1]国网湖北省电力有限公司直流公司,湖北宜昌443000 [2]国网湖北省电力有限公司孝感供电公司,湖北孝感432099

出　　处：《电力与能源》2024年第5期604-607,共4页Power & Energy

摘　　要：分布式电源在出现故障导致断路器分闸后,会从并网运行模式切换到孤岛运行模式,此时会失去大电网的频率支撑与电压支撑,对就地用电设备构成威胁。尽管存在多种分布式电源孤岛运行检测方法,但随着并网逆变器的数量逐渐增加,公共耦合点的电气参数变化显著,导致孤岛运行检测的准确率降低。为此,提出了一种向并网逆变器的功率外环主动注入具有规律波动的无功功率的方法。一旦分布式电源脱离电网进入孤岛运行状态,公共耦合点处的频率、幅值等参数会随着注入无功功率的变化而变化,从而可以快速识别出分布式电源的运行状态。仿真模型验证表明:该方法识别精度高、速度快。Distributed power generations may experience faults leading to breaker tripping and a switch from gridconnected to island operation,losing frequency and voltage support from the large grid,which can endanger local equipment.While many algorithms exist for detecting island operation,the increasing number of grid-connected inverters and significant changes in electrical parameters at common coupling points reduce detection accuracy.This paper proposes a method that actively injects reactive power into the power outer loop of grid-connected inverters,with the reactive power exhibiting regular fluctuations.If the distributed generation becomes islanded,changes in frequency and amplitude at the common coupling point will correspond to the injected reactive power,enabling rapid identification of the power operational state.Simulation results confirm that this algorithm offers high accuracy and fast detection speed.

关 键 词：孤岛运行 分布式电源 无功扰动 频率偏移 

分 类 号：TM73[电气工程—电力系统及自动化]