Development of adaptive autoreclosure algorithm in transmission lines

Autoreclosure provides a means of improving power transmitting ability and system stability. The conventional reclosure adopts the fixed dead time interval strategy, that is, the reclosure is activated after a time delay to restore the system to normal as quickly as possible without regard to the system conditions; however, these simple techniques cannot give the optimal operating performance. For this reason, various adaptive reclosure algorithms have been proposed until now. The variable dead time control algorithm is able to ascertain the secondary arc extinction time and distinguish a permanent fault from a transient fault using the voltage waveform. The optimal reclosing instant is the time when the transient energy of the post-reclosing system is minimum; a transient stability is maintained when reclosure is carried out at the optimal reclosing time. This paper presents an adaptive autoreclosure algorithm including the variable dead time and optimal reclosure. The reclosure algorithm performs the operations that are attuned to the power system conditions. The proposed adaptive reclosure algorithm is verified and tested using ATP/EMTP MODELS, and the simulation results show that the system oscillations are reduced by employing the proposed adaptive reclosure algorithm.