Cosine Similarity Based Line Protection for Large-Scale Wind Farms
Liming Zheng, Ke Jia, Tianshu Bi, Yu Fang, Zhe Yang
Abstract
In this article, power converters are used in the integrated wind farms and can change the fault characteristics of the power system. The conventional pilot protection suffers from low sensitivity, or even the risk of maloperation. In order to address these problems, the fault features of the transient current of various power sources are analyzed and a novel pilot protection based on cosine similarity is proposed. To validate the proposed protection, the real time digital simulator hardware-in-loop tests are carried out to verify the proposed method. In addition, a field short-circuit test is conducted in a real wind farm to examine the performances of the proposed protection. The results demonstrate that the proposed method can be potential option for industrial applications.