基于信号同步注入的多源配网阻抗测量防孤岛保护方法  

Anti-islanding Protection Method for Multi-source Distribution Network Impedance Measurement Based on Signal Synchronization Injection

作　　者：徐化博 陈羽[1] 徐丙垠[1] 王全 孙伶雁 孙中玉 王鹏玮 XU Huabo;CHEN Yu;XU Bingyin;WANG Quan;SUN Lingyan;SUN Zhongyu;WANG Pengwei(College of Electrical and Electronic Engineering,Shandong University of Technology,Zibo 255049,Shandong Province,China;State Grid Shandong Electric Power Company Jinan Power Supply Company Substation Maintenance Center,Jinan 250001,Shandong Province,China;School of Electrical Engineering,Shandong University,Jinan 250061,Shandong Province,China)

机构地区：[1]山东理工大学电气与电子工程学院,山东省淄博市255049 [2]国网山东省电力公司济南供电公司变电检修中心,山东省济南市250001 [3]山东大学电气工程学院,山东省济南市250061

出　　处：《中国电机工程学报》2024年第22期8834-8845,I0012,共13页PROCEEDINGS OF THE CHINESE SOCIETY FOR ELECTRICAL ENGINEERING

基　　金：国家自然科学基金项目(52077221)。

摘　　要：分布式电源(distributed generator,DG)并网运行需配备防孤岛保护,以避免电网停电产生非计划孤岛。阻抗测量法相比于过/欠压(over/under-voltage, OUV)和过/欠频(over/under-frequency,OUF)等被动式防孤岛保护,具有检测盲区小,不易误动等优势。但现有信号注入策略及孤岛保护判据无法应对多DG系统中信号干扰引起的保护失效问题。为此提出利用外部同步信号实现检测信号同步注入的阻抗测量方法。在分析孤岛前后DG测量阻抗特征的基础上,确定基于阻抗角的孤岛保护方案,并依据对线路参数,电网谐波及注入信号频率的分析,提出保护判据。最后,结合DG控制策略给出保护的信号注入及检测方法。基于RTDS的仿真验证表明,该文方法可有效辨识电网扰动及孤岛运行状态,并且避免了OUV、OUF的拒动及误动问题。Grid-connected distributed generators(DG)need to be equipped with anti-islanding protection to avoid unplanned islanding due to power grid blackouts.The impedance measurement method has the advantages of low non-detection zone and less prone to maloperation compared with passive anti-islanding protection such as over/under voltage and over/under frequency.However,in multi-DG systems,the existing signal injection strategy and islanding identification criteria cannot cope with the protection failure caused by signal interference between DGs.To this end,an impedance measurement method is proposed,which utilizes external synchronous signals to synchronize the injection of detection signals by each DG.Based on the analysis of the impedance measurement characteristics of the DGs before and after islanding,an impedance angle-based islanding identification scheme is determined and the identification criteria are proposed based on the analysis of line parameters,harmonics,and detection signal frequencies.Finally,the signal injection and the corresponding islanding identification method are presented in conjunction with the DG control strategy.Simulation verification based on RTDS shows that the method can effectively identify the grid disturbance and islanding state,and avoid the refusal and false action problems of over/under voltage and over/under frequency anti-islanding protection.

关 键 词：配电网 防孤岛保护 同步信号注入 阻抗角判据 卫星授时 

分 类 号：TM464[电气工程—电器]