DC bus voltage efficient sinusoidal multiple-phase generation with adapted saturation handling

The paper analyzes a variable common mode voltage injection technique for multi-phase sine wave pulse width modulation with improved computational efficiency compared to the Space-Vector Pulse Width Modulation (SVPWM) technique and fewer level switchings in the power inverter, which still achieves similar modulation and control performance in the case of two level voltage source inverters. Also, a simple saturation handling technique is proposed in order to limit the waveform distortions when used to drive an electric machine during high torque periods (e.g. during steep startup or disturbance rejection). The fewer level switchings in the power inverter lead to improved output power efficiency and decreased thermal dissipation, factors that represent essential constraints in the current automotive industry. The simulation results for the three-phase case are compared to Sinusoidal Pulse Width Modulation (SPWM) and SVPWM, taking into account the effective use of the DC bus voltage, the distortion in the generated voltage waveforms and the current feedback that is obtained.