GaN-based isolated bi-directional DC-DC converter for high load current application

The Gallium Nitride High-Electron-Mobility Transistor (GaN HEMT) is very attractive as a power semiconductor device and hence gaining its usage in high power and efficient power electronic circuits. This paper presents a GaN HEMT based isolated bi-directional Dual Active Bridge (IBDC-DAB) DC-DC converter for the high load current. The proposed GaN HEMT-DAB converter is operated using the Single-Phase-Shift (SPS) control strategy. The 650 V rated GaN HEMT based DAB converter delivered a constant output current of approximately 29 A, which would be idealistic for EV charging applications. Along with this, a comparison is also presented with a 650 V rated Silicon MOSFET (Si-MOSFET) based DAB converter. The GaN HEMT-DAB and Si MOSFET-DAB converters were compared for output voltage, power levels and the efficiency by considering the 600 V input DC-link voltage with variable phase-shift angle. The GaN HEMT-DAB and Si-DAB converters were able to achieve a maximum power rating of around 13 kW and 11 kW respectively under the same operating conditions. The performance metrics of the Si-DAB and GaN HEMT-DAB are analyzed and simulation results through LTspice XVII software are presented for validation.