Modeling and Prediction of Distribution System Voltage Distortion Caused by Nonlinear Residential Loads

Electric utilities have expressed concern over increased nonlinear loading of residential power distribution systems. The number and variety of power electronic products found in the typical home continues to grow rapidly, imposing a burden on local power companies to supply reliable, distortion-free service. In order to adequately prepare for the future, utilities must be able to predict the harmonic impact of new power electronic equipment and evaluate the ability of existing power systems to accommodate these nonlinear loads. This paper describes a modeling methodology that uses SPICE simulation software to predict the voltage distortion caused by nonlinear residential loads. Results of applying the methodology to a specific distribution system containing either of two different types of harmonic-rich loads, i.e., variable-speed air conditioners or electric vehicle battery chargers, are presented as well.