改进型主动式频率偏移孤岛检测算法分析 analysis of improved afd for island detection.pdfVIP

第 50 卷 总第 567 期 电测与仪表 Vol.50 No.567 2013 年 第 3 期 Electrical Measurement Instrumentation Mar. 2013 * 改进型主动式频率偏移孤岛检测算法分析 何军，赵钢 （天津理工大学 天津市复杂控制理论与应用重点实验室，天津300384 ） 摘要：针对目前常规主动式频率偏移法在户用型并网逆变器的孤岛检测中存在检测盲区的情况，本文提出一种 改进算法。 改进后的算法从正反两面施加频率的扰动，以消除负载对单一频率扰动方向的平衡作用。 给出了系 统的MATLAB/Simulink仿真模型，结果表明：改进型算法能够及时判断出施加频率的扰动方向，从而在2s 内检测 出孤岛。 关键词：AFD ；孤岛检测；检测盲区；单相并网；改进型AFD 中图分类号：TM615 文献标识码：A 文章编号：1001-1390（2013 ）03-0041-04 Analysis of Improved AFD for Island Detection HE Jun, ZHAO Gang （Tianjin University of Technology, Tianjin Key Laboratory of Control Theory Applications in Complicated Systems, Tianjin 300384, China ） Abstract: According to the fact that the existing conventional AFD spots none-detection zone through the island detection of household grid -connected inverter, a new improved AFD method is provided in this paper. Being different from conventional AFD, the new method can eliminate the counterbalance for the load on the influence of single frequency disturbance by way of putting frequency disturbance on positive and negative sides. Then a system simulation model based on the MATLAB/Simulink comes into being. It turns out to be that the improved AFD method can immediately estimate the direction of perturbation of applied frequency, and detects it in 2 seconds. Key words: AFD, island detection, none-detection zone, single-phase grid-connected, improved AFD 0 引 言 随着越来越多的光伏发电系统并入电网，对电网 的安全可靠运行提出了更高的要求。当电力系统的一 部分（包含负载和正在运行的分布式发电设备）脱离 了公共电网后单独对负载进行供电就形成了孤岛效 [1] 应 ，孤岛效应的出现必须及时得到抑制，否则会造成