A new type of adaptive reclosing merged with trajectory prediction for transmission lines

The reclosing moment for faulty transmission line greatly influences transient stability of power system. In allusion to the difficulty of online determination of the optimal reclosing moment, a method of online seizing on the reclosing moment, in which the trajectory prediction technology is merged with, is proposed. The core of the proposed method is to determine the dominant mode of oscillatory generation units by use of their trajectory prediction information of units' power angles and the units are divided into groups according to the dominant mode, thus the complex power system transient stability problem is turned into corresponding power angle stability analysis of one machine infinitive bus (OMIB) system, and the average stability margin of the first three swings of OMIB system mapping is chosen as the index to determine optimal reclosing moment. Because the amplitude of power angle in system mapping is inversely proportional to stability margin, so a practicable criterion is given as following: the minimum of the average power angle amplitudes of the first three swings of OMIB system mapping is the very condition satisfying the optimal reclosing moment. Finally, a complete design scheme for the proposed method is given.