An Accurate Technique for Discrimination between Transient and Permanent Faults in Transmission Networks

This paper presents an assessment study for adaptive single-pole automatic reclosure (ASPAR) schemes to select correctly the best scheme at responsible indices. Suggested solutions for the drawbacks that were noticed with the previous methods are investigated. In addition, this paper presents a proposed technique for ASPAR on transmission lines using wavelet packet transform(WPT). The ASPAR aims to discriminate between the faults' natures and to detect the instant of arc extinguished. The proposed technique uses an adaptive threshold level, and therefore, no adjustment is needed for various transmission systems. The proposed technique is examined at different fault scenarios that involve different fault locations, inception angles, and representation to secondary arc characteristics with various arc models. In addition, the behavior of ASPAR is well studied under power swing situation. The effects of shunt reactor compensators on the proposed technique are checked. The proposed scheme is tested for different network configurations, single and double circuits, to realize the robustness and the capability of the proposed scheme. The ATP/EMTP package is developed to emulate different fault signals to validate the proposed scheme. The proposed adaptive threshold scheme discriminates correctly between permanent and transient faults, thereby enhancing power system stability for compensated and uncompensated networks.