Harmonic Analysis of Grid Connected Power Electronic Systems in Low Voltage Distribution Networks

The aim of this paper is to analyze the power quality of a low-voltage distribution or a stand-alone network with different grid connected power converter topologies. Passive harmonic mitigation techniques are still attractive solutions in power converters. However, these solutions give different harmonic performances at a system level, where a large numbers of converter units are connected in parallel at a point of common coupling. This is due to harmonic cancellation within parallel converter at the system level, which depends on many different factors. Therefore, in this paper, the harmonic performance of a small grid system has been analyzed with respect to different grid and power electronic parameters. This paper also elaborates the importance of phase angle values of current harmonics in order to analyze the power quality of a grid. Harmonic performances of different three-phase power converter topologies have been compared individually. The analysis at the system level has been further extended by including single-phase converters in parallel with the three-phase power converters. A comprehensive modeling and simulation have been carried out in SABER and MATLAB/Simulink to verify the proposed analysis.