Accurate fault location algorithm for three-terminal lines without time synchronization considering unknown and different parameters of sections

摘要

The present study has introduced a new and precise fault location algorithm in three-terminal lines which, contrary to the existing algorithms, not only does not need synchronization of terminals data but also it does not require line parameters values. Moreover, parameters of the three sections are considered to be different from each other. In this technique, distributed parameters transmission line model in the time domain and data during fault are used. Of advantages of the proposed method are lack of need to categorize fault type, select faulty phase, lack of need for data regarding line parameters, and non-dependency on pre-fault conditions and network structure. Fault location is a two-phased process: the first one is concerned with detecting faulty part using faulty section index and the second one pertains to determining the exact fault distance. In the proposed algorithm, the faulty section and fault location are indirectly determined solving optimization problems, which are achieved by means of Teaching Learning-Based Optimization (TLBO). The proposed method has been tested under various conditions, yielding the results that reveal its high precision and lack of dependency on fault type, line parameters, synchronization angle, Thevenin impedance of external networks, fault resistance and fault incidence angle.