Tarbiat Modares University The Modares Journal of Electrical Engineering 2228-527X 12 2 2012 07 01 Application of S-transform for fault location in combined overhead line and cable distribution networks جایابی خطا در شبکه های توزیع شامل خطوط هوایی و کابل با استفاده ازتبدیل S 1 6 12774 EN Hamed Hasanvand Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran Soodabeh Soleymani Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran Behnam Feizifar . Istanbul Technical University (ITU), Turkey Bashir Bakhshideh Zad University of Mons, Belgium Journal Article This paper illustrates the application of S-transform and continuous wavelet transform (CWT) for fault location in combined overhead line and cable distribution networks. The high frequency transient signals originated by faults are analyzed using S-transform and CWT. The S-transform is found to be applicable in transient based fault location in distribution networks. This technique is an expansion of wavelet transform method and is based on a moving and scalable localizing Gaussian window. Taking into account this fact that the signal energy of faults has high amplitude around certain frequencies, the fault location can be identified considering the relationship between these frequencies and so-called path characteristic frequencies related to the fault traveling waves. The transient voltage signal energy is calculated using S-Transform and CWT. In order to demonstrate the effectiveness of the proposed method, the distribution networks with only overhead lines, as well as a combined system (consisting of the overhead lines and underground cables) have been studied. The IEEE 34-bus test distribution network is simulated in EMTP-RV software and the relevant S-transform and CWT analyses are carried out in MATLAB coding environment https://mjee.modares.ac.ir/article_12774_d0aae9539e4dd0bd618e5d2598f18707.pdf