Harmonic Sequence Impedances: A Tool for the Three-Phase Frequency Scan Technique

Abstract

In this paper, the harmonic response of an electric system under imbalance conditions is established. Symmetrical harmonic components are proposed to give a new way of interpreting resonance occurrence in three-phase power systems. A three-phase harmonic bus impedance matrix (THBIM) for a simple distribution system is derived using analytical procedures. The development of frequency scans for the THBIM elements in both phase and sequence reference frames is carried out. Simulation results show the benefits of the harmonic sequence components for characterization of the harmonic resonance conditions in unbalanced distribution systems, and for characterizing the effectiveness of the mitigating techniques. This method offers a new way to conduct harmonic analysis and diagnosis in unbalanced power systems.

Effective apparent power definition based on sequence components for non-sinusoidal electric power quantities

“…Using the two matrices manipulations (11) and (12), the following relationship between phase and sequence rms voltages can be obtained such as shown in (13):…”

“…The unbalanced voltages and currents phasors abc at hth harmonic order is then transformed to new three phasors called balanced, first unbalanced and second unbalanced. This new method has been presented as a powerful tool for the diagnosis purposes and the resonance occurrence evaluation as well as for modern power theory in distorted and unbalanced power systems [10][11][12].…”

Effective electric power quantities and the sequence reference frame: A comparison study

“…Some previous author's works have focused on the Girgis method in which they analyzed the harmonic resonance phenomena and evaluated the quantities defined in the IEEE Standard 1459-2010 in the sequence reference frame [9,10].…”

A Simple Predictive Method of Critical Flicker Detection for Human Healthy Precaution

“…Furthermore, flicker detection has been carried out based on wavelet Fourier transform [9], atomic method [10], new modified S-transform algorithm [11], and Chirp-z transform [12].…”