一种改进的正反馈主动移频孤岛检测方法

以主动移频法（Active Frequency-Drift,AFD）及基于正反馈的主动移频法（Active Frequency-Drift Positive Feedback,AFDPF）孤岛检测算法为研究基础,针对其检测盲区大、影响电能质量等缺点,提出了一种改进的正反馈主动移频检测方法。该方法通过检测频率偏差的大小,实时修改初始斩波因子和加速增益,缩短了检测时间,减小了检测盲区,降低了对电网电能质量的影响,同时,针对不同性质的负载,系统能对频率进行双向扰动,克服了单一方向扰动的缺点。仿真结果表明,该孤岛检测算法是可行的。

An improved active frequency-drift with positive feedback islanding detection method

Based on the islanding detection algorithm of active frequency shift method （AFD） and positive feedback active method, in terms of the disadvantages of its big non-detection zone and the influence to the power quality, an improved positive feedback active frequency drift detection method is proposed. The method can modify the initial chopper factor and the acceleration gain according to the size of the frequency deviation. It can shorten the testing time, reduce the non-detection zone and lower the impact on the power quality of the grid. At the same time ,for the different characteristics of the load, the system can disturb frequency from two directions, overcoming the shortcomings of single direction disturbance. The simulation results show that the islanding detection method is feasible.