主动移频法在光伏并网逆变器并联运行下的孤岛检测机理研究

孤岛检测是光伏并网逆变器所必备的功能。在各种孤岛检测技术中，主动移频法及改进后的带正反馈主动移频法被广泛采用。该类方法通过对逆变器输出电流的频率进行扰动来实现孤岛检测。目前针对该类方法的研究主要集中在单台逆变器。该文采用相位原理和基于负载品质因数与谐振频率坐标系的盲区空间理论，对多机并联工作方式下主动移频法及带正反馈的主动移频法之间的相互影响及孤岛检测有效性进行深入理论分析，揭示了多机并联下孤岛检测可靠性与工作条件的关系，仿真与实验验证了理论分析的正确性。

Islanding Detection Evaluation for Active Frequency Drifting Methods in Multiple Photovoltaic Grid-connected Converters

Islanding detection is a mandatory function for grid-connected photovoltaic (PV) converters. The active frequency drift method and the active frequency drift with positive feedback method are popular among all the islanding detection techniques. These strategies introduce perturbations in the frequency of the converter’s output current. The recent research has been mainly focusing on the islanding detection strategies for an individual converter. This paper is dedicated to investigating the interference and effectiveness of these two methods in multiple PV grid-connected converters. Simulation and experimental results are presented to validate the effectiveness of the theoretical analysis.