Harmonic source identification in distribution system using estimation of signal parameters via rotational invariance technique-total harmonic power method

Abstract

With proliferation of power electronics devices in the distribution system, harmonic distortion has become one of the major power quality (PQ) problems. In evolving the liberalized electricity market, it becomes necessary to develop suitable methods to allocate the responsibilities for the harmonic distortion to improve the PQ. This paper presents a new technique for harmonic source identification, which is based on total harmonic power (THP) method using estimation of signal parameters via rotational invariance technique (ESPRIT). Traditionally, harmonic powers for THP method is computed using Fourier transform, which inherits serious drawbacks of the discrete and fast Fourier transform, namely, inaccuracy owing to poor spectral resolution, spectral leakage, and so forth. Simulation results have been presented for different distribution system configurations and conditions, which confirms the improved capabilities of the proposed method in harmonic source identification.