Dead time compensation for three-level flying capacitor inverter with phase shift PWM

Multilevel inverter can obtain low distortion output voltage and current wave. However, dead time causes an output voltage error in the phase of inverter. Dead time error causes nonlinearity of output voltage and phase currents ripples with 5th and 7th order ripples of fundamental frequency. Current ripple decreases motor control performance. This paper presents dead time compensation for three-level flying capacitor inverter which is operated by phase shift pulse width modulation. This method is focused on the fact that power switching devices, which cause voltage error by dead time, depend on current polarities. The algorithm is simple, and the dead time is inserted at the instant of turning-on and turning-off of switching devices so as not to affect output voltage. The simulation result shows that high order harmonics which caused by dead time effect are eliminated using this method.