Improved SVPWM Strategy and Its Hybrid Technique to Reduce PWM Sideband Harmonics

In this paper, the sideband harmonic suppression and PWM noise reduction of PMSM are studied. Random zero vector duration SVPWM (RZVD-SVPWM) is proposed. RZVD-SVPWM has an obvious harmonic suppression effect on even times of switching frequency and it is easy to implement. However, its effect on harmonic suppression of twice the switching frequency needs to be strengthened to adapt to scenes with low noise requirements. Hybrid random zero vector duration SVPWM (HRZVD-SVPWM) is proposed to further improve the suppression effect of harmonics with twice the switching frequency. The simulation results show that RZVD-SVPWM and HRZVD-SVPWM have better suppression effect on sideband harmonics than conventional SVPWM. Among them, HRZVD-SVPWM is more complex to implement, but it has better effect on noise reduction.