Navid Ghaffarzadeh - Electrical Engineering Department Iran University of Science and TechnologyTehran
Sadegh Jamali - Electrical Engineering DepartmentIran University of Science and TechnologyTehran

A novel and simple approach for adaptive single pole auto-reclosing is proposed in this paper. The algorithm consists of capturing the faulted phase voltage using 20kHz sampling rate, decomposing it by db8 wavelet packet to attain the coefficients of nodes 257, 259 to 262 and defining an Index, which is obtained from the sum of the coefficients energy of nodes 257, 259 to 262. Finally, by evaluating the value of the Index, the transient, permanent faults and the secondary arc extinction instant can be identified. The significant advantage of the proposed algorithm is that it does not need variant threshold level and therefore its performance is independent of fault location, line parameters and the system operating conditions. Moreover, it can be used in the transmission lines with reactor compensation. The proposed method has been successfully tested under a variety of fault conditions on a 500KV overhead line using PSCAD/EMTDC software. The test results validate the algorithm ability in distinguishing between transient and permanent faults and determining the instant of secondary arc extinction.

Adaptive auto-reclosure, Permanent fault, Secondary arc,Transient fault, Transmission line, Wavelet packet transform