A three-port multilevel inverter with two DC ports and an AC port using Flying Capacitor Multilevel (FCML) design based on Gallium Nitride (GaN) switches is proposed in this paper. Recently, FCML inverter has shown a superior ability for power conversion with high power density, improved Total Harmonic Distortion (THD), and efficiency. The presented three-port multilevel inverter fits various applications such as battery and photovoltaic (PV) grid integration and standalone AC load. The proposed inverter is experimentally verified by building a 3-kW prototype using GaN switches which include two 4-level FCML converter paths, each share the same bus capacitor (C bus ), which links them together. One FCML path is 1 kW that incorporates an unfolder for the DC-to-AC conversion and has achieved a peak efficiency of 98.2% with AC voltage and current THDs of 1.26% and 1.23%, respectively. While the second FCML converter path is 2 kW used for the DC-to-DC conversion and has achieved a 99.43% peak efficiency.
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Cascaded H-Bridge MLI based Grid Connected Cell Level Battery Energy Storage System
This paper proposes a combination of cell-level energy processing and a Cascaded H-Bridge Multilevel Inverter (CHBMLI) for medium voltage, grid connected, battery energy storage systems. One isolated converter (Dual Active Bridge DC-DC Converter) manages each cell in the Battery Module, and the combination of Battery module and converter modules are cascaded to get the multi-level ac output voltage. The operating principle and control design of cell level isolated converter with double frequency ripple power, and the control strategy of the CHBMLI are presented. The performance of the battery cell level CHBMLI system with a 9-level inverter at small scale power level is validated through the simulations in MATLAB ® /SIMULINK ® software. The configuration holds promise for improving the performance and reliability of the battery modules at the cell level while also providing cell level galvanic isolation and high ac voltage.
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- NSF-PAR ID:
- 10156044
- Date Published:
- Journal Name:
- 2020 First International Conference on Power, Control and Computing Technologies (ICPC2T)
- Page Range / eLocation ID:
- 359 to 362
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/icpc2t48082.2020.9071430
