A Real-Time Synchronized Harmonic Phasor Measurements-Based Fault Location Method for Transmission Lines

Abstract

In this paper, a real-time synchronized harmonic phasor measurements-based fault location (RT-SHPM-FL) method for transmission lines is proposed. At transmission line protection center (TPC), the synchronized harmonic phasor measurements are obtained from all phasor measurement units (PMU) deployed in a power system. At each bus, the PMU estimates time-tagged 100 and 150 Hz phasors of 3-ɸ current signals in addition to fundamental phasor (50 Hz). The proposed RT-SHPM-FL method detects and locates a fault using the magnitude of 100 and 150 Hz phasors of 3-ɸ currents and equivalent harmonic phasors (EHPs), respectively. These EHPs are calculated from the magnitude of time-tagged 50, 100 and 150 Hz three-phase current phasors. For estimating the fault distance, the RT-SHPM-FL method has employed support vector regression (SVR), because of its mimicking nature, generalization and robustness. The functioning of the proposed fault location method has been validated in real-time on a scaled-down laboratory model of 400 kV extra high voltage (EHV) transmission line of 400 km long. The experimental results and discussions show that the proposed method locates transmission line faults accurately. Further, a comparative study of the proposed fault location method using SVR and adaptive neuro-fuzzy inference system has revealed that the former one is more reliable in fault location than the latter one since the error is within ± 1%.