Open AccessThree‐phase battery storage system with transformerless cascaded multilevel inverter for distribution grid applications
Author(s) -
Busarello Tiago Davi Curi,
Mortezaei Ali,
Bubshait Abdullah S.,
Simões Marcelo Godoy
Publication year - 2017
Publication title -
iet renewable power generation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.005
H-Index - 76
ISSN - 1752-1424
DOI - 10.1049/iet-rpg.2016.0629
Subject(s) - transformer , converters , energy storage , inverter , electronic engineering , electrical engineering , grid connection , grid , voltage , computer science , engineering , power (physics) , physics , geometry , quantum mechanics , mathematics
A distributed generator (DG) based on renewable energy is a promising technology for the future of the electrical sector. DGs may benefit utility companies and customers in a variety of perspectives. However, DGs suffer from intermittent behaviour. Storage systems appear as an attractive solution to support the continuous operation of DGs. The technology within the storage also plays an important role, since DGs and storage are connected in medium‐voltage grids. The use of batteries and the DC/AC converter in its conventional structure presents drawbacks in such grids. In this context, this study presents a three‐phase transformerless battery storage system (BSS) based on a cascaded H‐bridge inverter applied to a medium‐voltage grid. The BSS is composed of eight equal series connected H‐bridge converters, without bulk transformers, for connection to a distribution grid. Each converter contains 75, 12V/600Ah lead‐acid batteries. The converters are controlled through pulse‐width modulation at 600Hz. The BSS is able to keep working even with a failure of one of its converters. Reactive energy compensation not compensated by an existent passive filter is also performed. A case study with simulated and experimental results obtained through a hardware‐in‐the‐loop system is presented showing the efficacy of the proposed BSS.