| Summary: | For the asymmetric six-phase motor fed by a two-level six-phase voltage source inverter (VSI), when the modulation index is less than 0.5774, the motor operates in the linear region, and the harmonics in the Z<sub>1</sub> − Z<sub>2</sub> subspace can be suppressed to zero. When the modulation index is beyond 0.5774 and less than 0.6221, the motor operates in overmodulation regions, and the harmonics in the Z<sub>1</sub> − Z<sub>2</sub> subspace cannot be suppressed to zero. To minimize the harmonics in the Z<sub>1</sub> − Z<sub>2</sub> subspace for these regions, a harmonic suppression strategy, namely, harmonic suppression overmodulation strategy (HSOS), is proposed in this paper. The lower-order harmonics of the Z<sub>1</sub> − Z<sub>2</sub> subspace, namely, the 5th, 7th, 17th and 19th, are considered. Compared with the traditional four-vector overmodulation strategy (TFOS), the content of the 5th harmonic is reduced by about 20%, and the total harmonic distortion (<i>THD</i><sub><i>Z</i><sub>1</sub><i>Z</i><sub>2</sub></sub>) of these four kinds of harmonics is reduced by about 21% in the proposed HSOS. Finally, the simulation and experiment are carried out to verify the effectiveness of the proposed strategy.
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