Identify Resonant Frequencies in AC Distribution Networks – A Numerical Example Part II – The State Matrix Method☆

Abstract One of the most important issues regarding the operation of electrical distribution networks which is harmonic polluted is to avoid parallel resonance frequencies of relatively high harmonic currents, that are present in the network. For this is absolutely necessary to know the frequency response of the network or its harmonic impedance, more exactly, the frequencies which can produce parallel harmonic resonance. This article is the second part of the paper which presents two methods of calculating the parallel resonance frequencies corresponding to peaks (poles) harmonic impedance seen in the buses: harmonic nodal admittance matrix method (in the first part), respectively that state matrix method (in the second part). The results obtained by the two methods are compared and a qualitative and quantitative analysis is done.