低频电源注入式主动孤岛检测方案  

Active Islanding Detection Scheme Based on Low-frequency Power Supply Injection

作　　者：李瑞生[1] 郭宝甫[1] 曾正[2] 

机构地区：[1]许继集团有限公司,河南省许昌市461000 [2]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市400044

出　　处：《电力系统自动化》2017年第5期114-120,共7页Automation of Electric Power Systems

基　　金：国家高技术研究发展计划(863计划)资助项目(2015AA050104);国家电网公司科技项目(SGHADK00PJJS1500060)~~

摘　　要：用户侧并网的分布式电源发生孤岛运行的可能性较大,从用电安全和电能质量考虑,必须快速、准确地检测出孤岛。提出一种外加20Hz低频电源注入式主动孤岛检测方案,把相当于零序分量的20Hz分量注入380V系统,根据孤岛发生前后20Hz分量的变化特征识别孤岛。对方案的构成、检测原理、参数设计及对电能质量的影响进行详细描述和分析,并用MATLAB进行建模仿真,验证了分析结果的正确性。根据分析结果提出基于绝对值幅值比较原理的孤岛识别判据,并在分布式电源并网接口装置中进行了实现。最后,在某小型屋顶分布式光伏发电系统中进行了实验验证。The probability of islanding of grid-connected distributed generators is relatively large on the user side.Taking the user safety and power quality into account,the islanding mode should be detected quickly and accurately.An active islanding detection scheme based on 20 Hz low-frequency power supply injection is proposed.The 20 Hz component which is equivalent to zero sequence component is injected into the 380 Vsystem and islanding is identified by the change characteristics of the20 Hz component.The composition and detection principle of the proposed scheme,parameters selection and its influence on power quality are described and analyzed in detail.MATLAB is applied in the modeling and simulation,and correctness of the analysis is verified by simulation results.The identification criterion for the island mode based on comparison of the absolute value is proposed and realized in a grid-connected interface device.Finally,the scheme is experimentally verified in a small rooftop distributed photovoltaic generation project.

关 键 词：孤岛检测 低频电源 20Hz电压和电流 绝对值幅值比较 并网接口装置 

分 类 号：TM73[电气工程—电力系统及自动化]