The research on a novel islanding detection method

In order to solve the islanding detection problem in distributed generation systems,by analyzing the ratio of some related power quantity before and after the islanding,a new islanding detection algorithm is proposed based on summarizing the shortcoming of traditional islanding detection methods. The value of Δ f ΔPLis regarded as detection index,and the islanding identification is realized by comparing the evaluated value with the given threshold value.Taking the impacts of local load change of grid on islanding detection into account,simulation study is made to validate the proposed method.The experimental results show that the proposed method is simple and feasible, can detect the islanding fast and accurately and does not affect power quality.