Abstract: The dead time effect for three phase SPWM inverter will result in voltage distortions, zero current clamping effect, motor speed pulsation, and other bad consequences. By analyzing dead time effect, both theoretical derivation and simulation analysis are carried for the impact of dead time on fundamental wave and harmonics of the output voltage, and the relationship diagrams of the output voltage variation, power factor angle and modulation are obtained. Further, two novel compensation strategies, compensation with reference wave and logic circuits, are proposed in this work. Finally, the experiment is carried on a three phase SPWM inverter, which shows that these two proposed strategies can effectively reduce low harmonics and zero current clamping effect and improve system performance.