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This paper proposes a generalized Gallium Nitride (GaN) based modular multiport multilevel flying capacitor architecture. In other words, the attractive flying capacitor multilevel (FCML) design and the full-bridge unfolding circuit are employed to develop a multiport multilevel converter architecture that fits various applications. Each module can be designed to contain any combination of AC and DC ports connected through DC-to-DC and DC-to-AC power conversion paths. These conversion paths are FCML topologies that can be designed with any number of levels; the DC-to-AC paths incorporate the full-bridge unfolding circuit. Two example prototypes with open-loop control, three-port and four-port, have verified this generalized architecture. A single module 3 kW three-port four-level prototype with two DC ports and an AC port has achieved a compact size of 11.6 in 3 (4.8 in ×4.3 in × 0.56 in) and a high power density of 258.6 W/in 3 . The three ports are connected through DC-to-AC and DC-to-DC paths that have achieved peak efficiencies of 98.2% and 99.43%, respectively. The total harmonic distortion (THD) of the AC port's voltage and current are 1.26% and 1.23%, respectively. It operates at a high switching frequency of 120 kHz because of the GaN switches and has an actual frequency (inductor's ripple frequency) of 360 kHz thanks to the frequency multiplication effect of the FCML. The four-port prototype contains three DC ports and an AC port and achieved similar high figures of merit. These experimental results of the two prototypes of high efficiency, power density, and compact size are presented in this article and highlight this architecture's promising potential. The choice of the number of modules, ports, and levels depends on the application and its specification; therefore, this proposed generalized structure may serve as a reference design approach for various applications of interest.
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De-Embedding for Coupled Three-Port Devices
De-embedding techniques have been introduced to evaluate the real electrical performances of a device under test (DUT), e.g., the traditional thru-reflect-line and short-open-load-thru standards, where the transfer matrix (T-matrix) and its inverse form are adopted in the mathematical process. A DUT may have three coupled ports in the fields of radio frequency and electromagnetic compatibility. The symmetry in the corresponding S-matrix breaks down, because the numbers of incident and reflected ports are not equal. Thus, it leads to a nonsquare T-matrix by definition. Given that the inverse expression of a nonsquare matrix does not exist, the conventional de-embedding methods are inapplicable for a coupled three-port network. In this article, a de-embedding algorithm, which is feasible for coupled three-port devices, is proposed and verified through the measurement. The proposed de-embedding technique may also be applied on devices with more than three ports.
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- Award ID(s):
- 1916535
- PAR ID:
- 10695010
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Signal and Power Integrity
- Volume:
- 4
- ISSN:
- 2768-1866
- Page Range / eLocation ID:
- 185 to 190
- Subject(s) / Keyword(s):
- Scattering parameters Fixtures Printed circuits Three-dimensional printing Solid modeling Electromagnetic compatibility Performance evaluation Integrated circuit modeling Coupled Device Number Of Incidents Electrical Performance Transfer Matrix Electromagnetic Compatibility Inverse Form Measurement Instruments Printed Circuit Board Even Number Heat Sink Future Publications Permanent Magnet Synchronous Motor Braking System Two-port Network Three-phase Motor Multiple Ports AC bus bar coupling de-embedding S-parameter test fixture three-phase motor transfer-matrix (T-matrix)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1109/TSIPI.2025.3608692
