Analysis of dead-time effect for three-phase three-wire SPWM inverter

LIN Zhao， MA Hao， YIN Yi-di， WANG Xiao-rui
（Department of Electronic Engineering， Zhejiang University， Hangzhou 310027， China）

Abstract： Aiming at the dead-time effect caused by the dead time，such as the influence on fundamental wave of the output voltage and low harmonic content，a mathematical model was established. The relationship was analyzed between the dead-time effect and dead time，modulation coefficient，switching frequency and power factor angle on different conditions detailedly. The simulation was carried out in Matlab，and the experiment was proceeded in a 3 kW three-phase three-wire inverter. The theoretical analysis shows that dead time can reduce the output voltage fundamental amplitude and increase the low harmonic content. Theoretical curves coincide with fitting curves of simulation，experimental data basically，which verifies the correctness of the mathematical model and it has certain reference significance for the design of SPWM inverter.
Key words： three-phase three-wire； SPWM inverter； dead-time effect