Research Outputs

Now showing 1 - 2 of 2
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Publication

Design and Implementation of a Modular Multilevel Series-Parallel Converter for Second-Life Battery Energy Storage Systems

2024, Concha, Esteban, Dr. Lizana-Fuentes, Ricardo, Rivera, Sebastian, Alcaide, Abraham

Battery Energy Storage Systems (BESS) offer scalable energy storage solutions, especially valuable for remote, off-grid applications. However, traditional battery packs with fixed series-parallel configurations lack reconfigurability and are limited by the weakest cell, hindering their application for second-life batteries. The Modular Multilevel Series-Parallel Converter (MMSPC) addresses these limitations by enabling dynamic reconfiguration, optimizing cell balancing, and enhancing energy control. This paper experimentally evaluates a single-phase BESS based on the MMSPC with an output power equivalent to 2 kW and two battery units (155V), demonstrating stable output and reduced internal losses across varied battery parameters.

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Operation of a hybrid energy storage system based on a cascaded multi-output multilevel converter with a carrier-based modulation scheme

2023, Dr. Lizana-Fuentes, Ricardo, Figueroa, Fidel, Goetz, Stefan, Rivera, Sebastian

Hybrid Energy Storage Systems (HESSs) have gathered considerable interest due to their potential to achieve high energy and power density by integrating different storage technologies, such as batteries and capacitors, to name a few. Among the various topologies explored for HESSs, the multi-output multilevel converter stands out as a promising option, offering decoupled operation of the AC ports while maintaining an internal balance among the diverse storage units. In this paper, the operation and restrictions of a HESS based on a multi-output multilevel converter with a carrier-based modulation scheme are presented. The study provides compelling evidence of the correct operation of the proposed modulation scheme and highlights its advantages, including simplicity and stability.