电压协同的多源配电网阻抗角测量防孤岛保护方法  

Anti-islanding protection method for impedance angle measurement of multi-source distribution network based on voltage coordination

作　　者：高宜凡 陈益哲 甘锴 王超 徐化博 GAO Yifan;CHEN Yizhe;GAN Kai;WANG Chao;XU Huabo(Zhaoqing Power Supply Bureau of Guangdong Power Grid Co.,Ltd.,Zhaoqing 526060,China;Shandong Kehui Electric Automation Co.,Ltd.,Zibo 255087,China)

机构地区：[1]广东电网有限责任公司肇庆供电局,广东肇庆526060 [2]山东科汇电力自动化股份有限公司,山东淄博255087

出　　处：《供用电》2024年第9期78-89,共12页Distribution & Utilization

基　　金：中国南方电网有限责任公司科技项目(031200KK52222025(GDKJXM20222218))。

摘　　要：随着配电网中分布式电源(distributed generator,DG)渗透率的提高,电网停电引起的非计划孤岛问题日益严峻。阻抗测量防孤岛保护方法因检测盲区小、不易误动、电能质量影响小等优势,日益受到人们的关注,但多源配电网中DG数量变化及注入信号相互干扰会导致保护失效。为此,提出基于电压协同注入的阻抗角测量防孤岛保护。首先,设计了基于阻抗角测量的孤岛辨识判据,避免了DG运行数量变化的影响。然后,结合DG控制策略,设计了一种信号注入及阻抗角测量方法。所提方法使得各DG在检测到电压变化时同步注入0.04 s的孤岛检测信号,避免了信号干扰问题,降低了对电能质量的影响。最后,基于实时仿真软件平台RTDS进行仿真验证,证明所提方法可以准确辨识电网扰动及孤岛,有效避免了现有保护存在的拒动及误动问题。With the increase of the access ratio of distributed generator(DG)in the distribution network,the problem of unplanned island caused by power outage is becoming more and more serious.Anti-islanding protection based on impedance measurement has gained increasing attention due to the advantages of low non-detection zone,less susceptibility to false activation,and less impact on power quality.However,variations in the number of DGs and mutual interference of islanding detection signals in multi-source distribution networks can lead to impedance measurements against protection failure Therefore,impedance angle measurement based on voltage synergistic injection is proposed to prevent islanding protection.Firstly,an islanding identification criterion based on impedance angle is designed to avoid the influence of DG running number change on protection.Then combined with the DG control strategy,the signal injection and impedance angle detection methods are designed.The proposed method makes each DG synchronously inject 0.04s islanding detection signal when detecting voltage changes,which avoids the mutual interference of the detection signals and reduces the impact on power quality.Finally,the simulation experiments based on RTDS show that the proposed method can accurately identify the power grid disturbance and island operation state,and effectively avoid the problems of the protection rejection and the false activation.

关 键 词：分布式电源 多源配电网 电压同步 防孤岛保护 阻抗角测量 

分 类 号：TM72[电气工程—电力系统及自动化]