Wavelet Transform Modulus Maxima-based Fault Location Method for Three-Terminal Transmission Line

This paper introduced a new wavelet transform modulus maxima-based fault distance method for three-terminal transmission lines. The presented method decouples the phase currents using Clark's transformation. Then, the modulus maxima of the wavelet transform (WTMM) signal is calculated for the identification of the arrival of traveling waves. The proposed method uses WTMM corresponding to an aerial and zero-mode component of traveling wave to identify the correct faulty line section. The next task of fault distance calculation is carried out using a single-ended traveling wave method. The proposed method requires the current data measured un/synchronized at all the terminals of transmission line. This method is applicable to ground faults only. The method remains valid even for faults which are very close to the terminal and junction point of three line-section. The authenticity of this scheme is evaluated by simulating different scenarios with the frequency-dependent line model of the three-terminal transmission line in a software EMTDC/PSCAD. The results indicate a good level of accuracy for the proposed fault location method.