Abstract
The ac-ac dual active bridge (DAB) converter is an advanced bidirectional two-port grid interface converter that facilitates active and reactive power flow control between two grids without a dc-link capacitor. This article presents a novel modeling approach for the ac-ac DAB converter using the extended generalized average modeling (EGAM) technique. Unlike the conventional generalized average modeling (GAM) framework, the ac-ac DAB converter's dynamic state variables, including the leakage inductor current and ac grid side LC filters, exhibit grid and switching frequency components, making the standard GAM framework unsuitable for dynamic modeling involving two distinct excitation frequencies. Furthermore, the 2-D GAM (2D-GAM) framework, although capable of capturing the dynamics of two frequencies and their cross interactions, fails to handle product terms involving double fourier series (DFS) states resulting from the switching terms in the ac-ac DAB converter. To address these challenges, the EGAM technique is proposed, which involves transforming the DFS product terms in the time domain into the 2D-convolution of their discrete fourier images (DFI) in the frequency domain. As a consequence of this analysis, it is shown that in an ac-ac DAB converter, the power is transferred in the grid-switching sideband frequency components at the bridge level. The effectiveness of the EGAM modeling framework is demonstrated through extensive simulation and hardware experiments, and the results are compared with PLECS results, validating the accuracy and efficacy of the proposed approach.
Recommended Citation
K. J. Veeramraju and J. W. Kimball, "Dynamic Model Of AC-AC Dual Active Bridge Converter Using The Extended Generalized Average Modeling Framework," IEEE Transactions on Power Electronics, vol. 39, no. 3, pp. 3558 - 3567, Institute of Electrical and Electronics Engineers, Mar 2024.
The definitive version is available at https://doi.org/10.1109/TPEL.2023.3344378
Department(s)
Electrical and Computer Engineering
Keywords and Phrases
Dual active bridge (DAB) converter; dynamic phasor modeling; generalized averaged models; inverters; multifrequency averaging; power electronic converters; solid-state transformers (SST)
International Standard Serial Number (ISSN)
1941-0107; 0885-8993
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Institute of Electrical and Electronics Engineers, All rights reserved.
Publication Date
01 Mar 2024
Comments
U.S. Department of Energy, Grant None