Interleaving impact on harmonic current in DC and AC passive components of paralleled three-phase voltage-source converters

This paper presents a complete analysis studying the impact of interleaving on harmonic current in DC passive components for paralleled three-phase voltage-source converters (VSCs). The analysis performed considers the effects of modulation index, displacement angle, and the interleaving angle. The results show that the harmonic current in DC capacitor depends strongly on displacement angle, and to minimize the harmonic current interleaving angle should vary from pi/2 to pi as the displacement angle varies from zero (unity power factor) to pi/2 (zero power factor). The modulation index can also affect the impact much. Because of the limit of the pages, the impact of interleaving on harmonic current in AC boost inductor is only shown in principle. All the analysis is based on an example system containing two VSCs. However the proposed analysis method in frequency domain is easily expandable for multiple paralleled VSCs. Experimental results have verified the analysis results.