A Bidirectional Buck-boost Converter Using 1.3kV Series-Stacked GaN E-HEMT Modules for Electric Vehicle Charging Application

In this paper, an all-Gallium Nitride (GaN) bidirectional buck-boost converter using series stacked GaN Enhancement High Electron Mobility Transistor (E-HEMT) modules for Electric Vehicle (EV) charging application is proposed. A Series Switch Driver (SSD) is proposed for controlling series-connected GaN HEMTs. In this circuit, a single gate driver supply is used. The function of the proposed gate driver is to provide the required gate charge for the devices and ensure turn-on and off synchronization between the devices. A mathematical model is derived for the series-stacked GaN HEMTs (GaN module) along with the designed gate driver. In this model, the parasitic inductors are also considered and the switching loss is calculated. Simulation and experimental results of the proposed converter validate the theoretical analysis.