A Novel Compensation Strategy to Asymmetric Dead time Based on Three Level Inverter

In this paper, space vector modulation (SVPWM) is used as the switching modulation strategy of three level diode midpoint clamp inverter. The influence of power switch tube, diode tube voltage drop, conduction delay on dead zone compensation and the calculation method of dead zone time are introduced in detail. The asymmetry of the dead time compensation on the vector action time in the unit switching period is studied. Based on the dead zone compensation time calculation method in this paper, the dead zone compensation of asymmetric vector action time is proposed in a switching period according to the current direction of the AC side. The experimental results show that the modulation method in this paper can effectively reduce the THD value of the system and avoid the phenomenon of asymmetric compensation time of dead time in each switching cycle.