Wavelet packet transform applied to a series-compensated line: A novel scheme for fault identification

For series-compensated transmission lines (SCTLs), identification of the fault section with respect to the compensator as well as fault phase selection are important issues. In this paper, first, the various methods applied for SCTLs are classified and discussed according to specified performance indices selected by the operator. Further, an investigation of solutions to their drawbacks is presented. Second, a novel scheme based on the application of wavelet packet transform (WPT) is proposed for an SCTL. A db10 wavelet packet is used for decomposing the faulted phase current waveform to obtain the energy coefficients. Third, the ATP/EMTP package is used to test and validate the proposed scheme, in which several fault scenarios with different fault locations, inception angles, fault resistances, noise, and variation in voltage and source impedance are examined to show its robustness. The effectiveness of the proposed scheme is demonstrated compared to other methods in the literature.