Power Factor Correction of Linear Loads Under Unbalanced Voltage Conditions

Power factor correction of linear loads supplied from balanced 3-phase sources has been studied in extensive detail over the past century. However, it is not uncommon for the voltage at the load terminals to become unbalanced due to a variety of different reasons. Unfortunately, the power factor correction algorithms that fail to take voltage unbalance into account are often rendered ineffective during unbalanced voltage conditions. Even though several studies have indeed focused on power factor correction during unbalanced voltage conditions (also often referred to as asymmetrical voltage conditions), their scope has been mainly limited to the discussion of fundamentals. Simulation results depicting the power factor correction of linear loads using a passive LC compensator during unbalanced voltage conditions are presented in this paper. The compensator's design is based on the Currents' Physical Components (CPC) Power Theory, while the simulations are performed in the Electromagnetic Transients Program (EMTP). A brief discussion of the fundamentals of the design of the compensator is presented as well.