Performance Evaluation of Soft-and Hard-Switched Inverters Based on Monolithically-Integrated Bidirectional GaN Devices

• Applicant: Professor Dr.-Ing. Marco Liserre, Ph.D.
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 462668222

GaN-HEMTs with a monolithically bidirectional switch (MBS) integration achieve symmetric conduction and blocking voltage capability at a reduced on-state resistance/parasitic capacitance compared to their discrete-based counterparts. This four-pin device is constructed based on a lateral p-GaN chip design with a common-drain offering four-quadrant operation. This is an alternative to the conventional bidirectional semiconductors constructed based on discrete WBGs, achieving higher overall power density and efficiency of the power converter. The main utilization of bidirectional GaN is for Vienna/Swiss rectifier, Matrix/current source converters, and inverters with T-type-based configuration. Its contribution can also be extended to some emerging applications like controllable resonant tank in resonant converters and isolation switch in modular dc-dc converters, as investigated in the first phase of this project. The second phase of the project wants to explore the potential of the MBS-GaN devices in soft and hard switched inverters in comparison to non-monolithic integrated bidirectional GaN devices considering gate driver requirements, thermal management and short-circuit endurance. The project will target to develop inverter topologies specifically developed for MBS-GaN devices. The goal of this project is to show a clear improvement of the existing topologies with the utilization of MBS-GaN and a case-to-case analytical comparison with its discrete-based counterparts. The project contains three objectives with six work-packages and is defined for a three-year research program. Device level characterization and a formal methodology for gate driver design of hard and soft-switched inverters are developed in the first year. Utilization of MBS-GaN into inverter stage of the resonant dc-dc converters, variable-frequency resonant tank with the concept of electronic-embedded transformer, and the device potentiality in two-level or multilevel soft-switched ARCP-based inverters are investigated as the second objective. And finally, the incorporation of MBS-GaN into new multilevel converters aiming to evenly distribute the losses and to achieve better efficiency is the third objective of this project.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2312: Energy Efficient Power Electronics "GaNius"