Analytical approach of circulating currents mitigation effect using coupled inductor in the parallel three-phase boost converters

This paper analyzes characteristic of the three-phase coupled inductor connected to ac source to effectively mitigate the high-frequency circulating current generated in the parallel three-phase boost converters. The three-phase coupled inductor analysis presented in this paper uses the three-phase coupled inductor structure and voltage equations. Based on this analysis, the three-phase coupled inductor is added to the conventional averaged model. As a result, the novel averaged model which can reduce the low and high-frequency circulating current simultaneously is developed. Using the zero-sequence component of the novel averaged model, each total inductance to the circulating current of the three-phase coupled inductor and line inductor can be obtained. Simulation and experiment results verify the usefulness of three-phase coupled inductor in the parallel three-phase boost converters.