Double-delta sourced winding for dual winding induction machine

The harmonic distortions of motor currents can be mitigated by the application of the double-delta sourced winding (DDSW), which implements multi-level operation with two-level converters. In practice, dual winding induction machine (DWIM) has been considered for this application due to its inherent compatibility to DDSW. The modeling of DWIM is discussed for the vector control, and a decoupling control method of each winding to the other is proposed to improve the dynamic response of the current regulation. The torque control is also discussed for the case where one of the converters is dropped out. The effectiveness of the proposed methods is assessed with experimental results. It has been confirmed that the total harmonic distortion of the converter currents was decreased by 67.7 % when DDSW was applied to an 11 kW DWIM. In addition, the bandwidth of the current regulation could be increased by 113.7 % thanks to the proposed decoupling control method.