Intrinsic time decomposition based fault location scheme for unified power flow controller compensated transmission line

摘要

The transmission line fault location algorithms are affected in presence of FACTS device like unified power flow controller (UPFC) due to changed voltage and currents signals at the relaying point after occurrence of fault. Additionally, these algorithms involve high computation burden associated with signal processing techniques and are proven to be in-efficient during severe power system conditions. To eliminate the limitations stated above, a novel travelling wave aided intrinsic time-decomposition (ITD) based fault location algorithm is presented in this paper for estimation of fault location in UPFC employed transmission lines. ITD offers several advantages over other time-frequency-energy (TFE) analysis tools such as presenting precise temporal information and involving less computation burden. ITD decomposes a given signal into a sum of proper rotation components (PRCs) followed by a monotonic trend. The proposed ITD based fault location algorithm estimates the arrival times of travelling waves from first PRC of modal voltage signals of the terminals to which the transmission line is connected. From the estimated arrival times, the fault location is calculated. For simulation, a 100 MVA UPFC controlling the power flows in a 500 kV transmission system is used. Different cases of faults with diverse power system conditions are applied to examine the robustness and efficacy of ITD based fault location algorithm. Further, ITD base method is compared to existing methods available in literature and found to be a better performer in the context of fault localization.