Empirical Mode Decomposition Assisted Fault Localization for UPFC Compensated System

In this work, traveling wave aided fault localization scheme (FLS) for UPFC compensated system using empirical mode decomposition (EMD) method is proposed. In this scheme, the instantaneous voltages measured at both ends of the transmission line is transformed to modal signals using Clark's transformation. The modal voltage signals (mode $\alpha)$ is then decomposed using EMD and the first intrinsic mode function (IMF1) of the signal is extracted. The arrival time of waves (ATWs) are estimated from the first sharp peak (negative or positive) of IMF1 after the inception of fault. The estimated ATWs are then used to localize the fault. For simulation, a 500 kV transmission system with 100 MVA UPFC is modeled in MATLAB. To validate the effective performance of FLS, different case studies of diverse fault and operating conditions are considered. Further, a comparative assessment of proposed FLS with reported techniques is presented to illustrate its satisfactory performance.