Input Impedance Characterization of a Power Factor Corrected Rectifier for Harmonic Power Flow Studies

The presence of power electronic loads can significantly impact the damping of harmonic propagation on an electric power system. This is of relevance in harmonic analysis when considering power quality issues from nonlinear loads such as arc furnaces and when calculating signal attenuation in power line communications (PLC). On account of recent European Union (EU) regulations, existing passive rectifiers are increasingly replaced with power factor corrected (PFC) rectifiers. Simulation results have suggested that the input impedance of these devices is not only affected by their circuit topology but also the design of the control system. Due to the potential for resonances at frequencies above 10 kHz, sufficient models are necessary to perform accurate harmonic power flow studies. This paper presents experimental results of power factor corrected rectifiers and provides a lumped circuit model for use in harmonic analysis up to 100kHz. The experimental results were performed in a laboratory using a commercially available PFC power supply unit supplying controllable electronic loads. The lumped circuit model can be applied in existing power system analysis software to perform harmonic studies.