Zero-Sequence Current Suppression Strategy for Open Winding PMSG Fed by Semicontrolled Converter

The open winding permanent magnet synchronous generator (PMSG) fed by semicontrolled converter takes the advantages of lower expense, simplified driving circuit, and reliable control realization. With a single dc supply, the implementation of open winding configuration in practical application could be much convenient. However, the common dc bus supplied configuration provides a zero-sequence current circuit unavoidably. In order to reduce the harmonic distortion, a zero-sequence current suppression scheme is proposed. The space vector pulse width modulation (SVPWM) technique is adopted to modulate the desired voltage reference in the three-dimensional (3-D) coordinate system by distributing duty cycles for active and zero vectors. With a comprehensive investigation on the semicontrolled configuration, the achievable modulation region for αβ0 voltage vector reference is analyzed. Finally, the zero-sequence current suppression method with 3-D-SVPWM technique is implemented in a 1 kW open winding PMSG experimental system.