Dead Time Reverse Conduction Investigation in GaN-Based Inverter for Motor Drives

The paper deals with the reverse conduction during the dead time of low-voltage GaN FETs in inverters for motor control applications. The current variation caused by the sinusoidal modulation in an AC motor drive leads to a different dead time losses mechanism when compared to the DC-DC converter application, which is worth investigating. The reverse conduction is correlated with both current variation and GaN technology in inverter legs applications. Furthermore, the GaN FET device’s reverse conduction is compared to equivalent low-voltage MOSFET devices, considering the different static and dynamic characteristics. This work aims to provide inverter designers with an investigation and a guideline on the dead time selection and its limits in an inverter leg for motor control with the last generation of GaN FET devices.