High speed adaptive auto reclosing of 765 kV transmission lines

This paper proposes a new adaptive auto reclosing scheme for extra high voltage transmission lines. The performance of an auto reclosing scheme depends not only on power system behavior and transmission lines characteristic but also secondary arc current. In this paper at first, an appropriate model of arc in extra high voltage transmission overhead line is investigated and after that, using symmetrical components a novel criterion based on apparent power is presented in order to detect the exact time of arc extinguishing. In fact this criterion has the ability to distinguish between transient faults and permanent faults by detecting the exact time of arc extinguishing. Also, a generalized scheme is presented in order to have high speed auto reclosing in 765 kV transmission lines. This method is very simple and only uses two filters, so it needs to low hardware requirements. Therefore, application of this method is highly recommended in extra high voltage transmission lines. The simulation studies of this paper are performed by PSCAD/EMTDC software and the results show satisfactory performance of the proposed method.