Using an Evolutionary Algorithm for Harmonic Load Modeling by Norton and Thevenin Equivalents

Abstract

The Norton equivalent model for harmonic load modeling is used widely. The parameters of the model are usually calculated analytically. These calculations are based on measured or simulated voltage/current waveforms. In this case, harmonic analysis is needed to obtain the harmonic spectra. After this step, model parameter values are calculated for each harmonic separately. Relative phase shifts of all measured harmonic voltages and currents are most important for correct calculation of Norton model parameters. Different estimations in the power network are used to determine the phase shifts. The use of an evolutionary algorithm to determine the voltage and current harmonic phase shifts is researched in the paper. The proper optimization problem is defined and an evolutionary algorithm is used to solve the problem. The verification of the method will be done by comparing simulated waveforms obtained by a computer program.