Effect of parasitic capacitance of power device on output voltage deviation during switching dead-time in voltage-fed PWM inverter

The PWM inverter, which is operated at a high carrier frequency, is influenced by the switching dead-time. In this paper, the effect of the parasitic capacitance of the power device on the voltage deviation during switching dead-time is investigated and a numerical method to analyze the output voltage deviation in consideration of the parasitic capacitance of the power device is proposed. Furthermore, this method is applied to a permanent-magnet AC servo motor drive system and the voltage deviation and the phase current waveforms are calculated. Finally, the calculated results are compared with the experimental results in order to confirm the validity of the analysis.