基于特征频次谐波电压的孤岛检测方法  

ISLANDING DETECTION METHOD BASED ON CHARACTERISTIC FREQUENCY HARMONIC VOLTAGE

作　　者：高淑萍[1,2] 郭芳宾 宋国兵 李晓芳[1,2] 蔚坤 Gao Shuping;Guo Fangbin;Song Guobing;Li Xiaofang;Yu Kun(College of Electrical and Control Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;Xi’an Key Laboratory of Electrical Equipment Condition Monitoring and Power Supply Security,Xi’an 710054,China;School of Electric Engineering,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安科技大学电气与控制工程学院,西安710054 [2]西安市电气设备状态监测与供电安全重点实验室,西安710054 [3]西安交通大学电气工程学院,西安710049

出　　处：《太阳能学报》2025年第3期254-262,共9页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(51777166);国家自然科学基金国际合作与交流项目(52061635105);国家电网有限公司总部科技项目(52094020006U)。

摘　　要：当分布式电源与主电网失去连接时应切断对本地负荷的供电,为迅速可靠地检测到这种状态,保证系统安全稳定运行,以三相分布式电源并网逆变器的孤岛检测技术为研究对象,提出一种基于分布式发电(DG)侧和电网侧特征频次谐波电压的被动式孤岛检测新方法。首先,对公共连接点处两侧谐波责任进行划分,根据谐波责任划分结果选取两侧对公共连接点处谐波电压影响最大的特征频次谐波用于孤岛检测并给出整定判据。其次,对孤岛前后公共连接点处谐波电压比值的理论值进行推导,当孤岛前后两侧特征频次谐波电压参数的变化都超过整定阈值时则判断发生孤岛。最后,根据IEEE Std.1547.1孤岛检测标准对所提方法进行验证。仿真结果表明,该方法可快速、准确、有效地检测出孤岛。该方法采用双重判据可减少误判的可能性、提高孤岛检测的可靠性,与传统基于谐波域的被动式孤岛检测方法相比,该方法可避免检测频次谐波困难、阈值难以确定、受背景谐波影响的问题。When the distributed power supply is disconnected from the main grid,the power supply to the local load should be cut off.In order to quickly and reliably detect this state and ensure the safe and stable operation of the system,this paper focuses on the islanding detection technology for three-phase grid-connected inverters in distributed power systems and proposes a novel passive islanding detection method based on the characteristic frequency harmonic voltages at the distributed generation(DG)side and the power grid side.Firstly,the harmonic responsibility of both sides at the common connection point is divided.According to the result of harmonic responsibility division,the characteristic frequency harmonics that have the greatest influence on the harmonic voltage at the common connection point are selected for islanding detection,and the setting criterion is given.Secondly,the theoretical value of the harmonic voltage ratio at point of common coupling before and after the island is deduced.When the variation of characteristic frequency harmonic voltage parameters on both sides of the islanding exceeds the setting threshold,the islanding is judged to occur.Finally,the proposed method is verified according to IEEE Std.1547.1 islanding detection standard.The simulation results show that this method can detect occurrence of islanding operation quickly,accurately and effectively.This method uses double criteria to reduce the possibility of misjudgment and improve the reliability of islanding detection.Compared with traditional passive islanding detection methods based on harmonic domain,this method can avoid the problems of difficulty in detecting frequency harmonics,difficulty in determining the threshold and being affected by background harmonics.

关 键 词：可再生能源 分布式发电 阈值电压 孤岛检测 谐波责任 背景谐波 

分 类 号：TM712[电气工程—电力系统及自动化]