Feasibility of quasi-square-wave zero-voltage-switching bi-directional dc/dc converters with gan hemts

There are trade-offs for each power converter design which are mainly dictated by the switching component and passive component ratings. Recent power electronic devices such as Gallium Nitride (GaN) transistors can improve the application range of power converter topologies with lower conduction and switching losses. These new capabilities brought by the GaN High Electron Mobility Transistors (HEMTs) inevitably changes the feasible operation ranges of power converters. This paper investigates the feasibility of Buck and Boost based bi-directional DC/DC converter which utilizes Quasi-Square-Wave (QSW) Zero Voltage Switching (ZVS) on GaN HEMTs. The proposed converter applies a high-switching frequency at high output power to maximize the power density at the cost of high current ripple with high frequency of operation which requires a design strategy for the passive components. An inductor design methodology is performed to operate at 28 APP with a switching frequency of 450 kHz. In order to minimize the high ripple current stress on the output capacitors an interleaving is performed. Finally, the proposed bi-directional converter is operated at 5.4 kW with 5.24 kW/L or 85.9 W/in3 volumetric power density with air-forced cooling. The converter performance is verified for buck and boost modes and full load efficiencies are recorded as 97.7% and 98.7%, respectively.


Characterization of gan transistors and developmentof bi-directional dc/dc converter with half-bridgehaving short circuit protection for parallel switches
Karakaya, Furkan; Keysan, Ozan; Department of Electrical and Electronics Engineering (2020-9)
Wide band-gap semiconductors are superior to Si-based semiconductors with their increased electron mobility and breakdown strength which leads to small package sizes, low parasitics, and increased switching frequency capability. Efficient and dense power converter could be obtained with wide band-gap devices especially GaN transistors. This thesis investigates the GaN HEMTs in terms of their characterization and pplication. The gate charge and output capacitance of GaN HEMTs are characterized by designed ex...
Baştüzel Çakmak, Özlem; Durgun, Ahmet Cemal; Department of Electrical and Electronics Engineering (2022-2-9)
Radio frequency (RF) power amplifiers (PAs) are the most crucial part for the development of high performance front-end RF and microwave systems. Power transistor is the key component of a power amplifier, which should be accurately modeled to provide good correlation between simulation and measurement results. Bare die transistor needs to be packaged, before attaching on printed circuit boards (PCBs) to provide protection, easy fabrication and prevent mechanical issues. In recent years, Gallium Nitride (Ga...
Active clamped ZVS forward converter with soft-switched synchronous rectifier for maximum efficiency operation
Acik, A; Cadirci, I (1998-05-22)
An active-clamped, zero-voltage switched forward converter equipped with a soft-switched synchronous rectifier is designed and implemented for some low output voltage applications where maximized efficiency is of utmost importance. The converter efficiency is maximized due to soft-switching of the main, active clamp and the synchronous rectifier MOSFET switches. Experimental results are presented for a converter with a de input voltage of 48V, an output voltage of 5V and a de electronic load up to 10A. The ...
Design and implementation of an unregulated DC DC transformer DCX module using LLC resonant converter
Alemdar, Şahin; Keysan, Ozan (2016-08-20)
Traditional high-power centralized front-end DC/DC converter can be replaced with an array of paralleled standardized DC/DC transformer (DCX) modules when load current sharing is accomplished between individual modules. In this study, an LLC resonant converter is proposed as an unregulated DCX module, which has current sharing capability. Current sharing feature is implemented by using the droop current sharing method. A methodical design process is presented for the selection of the resonant tank component...
Investigation of parallel-connected GaN E-HEMT VSI-based servo drives
Yürük, Hüseyin; Keysan, Ozan; Department of Electrical and Electronics Engineering (2022-1-19)
Nonlinearities in voltage source inverters (VSIs) are thought to be the primary cause of output voltage distortions which cause low-order harmonics in the output current. These nonlinearities also considerably degrades control performance and system stability for low-speed applications with low-inductance motors, particularly when the system operates in the low-torque area. The impact of the nonlinearities on the phase current and current control of a silicon (Si) metal-oxide-semiconductor field-effect tran...
Citation Formats
F. Karakaya and O. Keysan, “Feasibility of quasi-square-wave zero-voltage-switching bi-directional dc/dc converters with gan hemts,” Energies, pp. 0–0, 2021, Accessed: 00, 2021. [Online]. Available: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85106956915&origin=inward.