To overcome the non-detection zones of traditional active frequency drift，a novel method of active islanding detection is proposed，called the active low-frequency drift method.The islanding detection principle of the method is discussed，and the relationship between parameters and the power factor and harmonic current is analyzed in detail，as is the impact of quality factor of the local load on detection effect.The judgment rule of islanding detection in this method is summarized.Simulation and experimental results have proved the effectiveness of the proposed method.