{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T17:53:10Z","timestamp":1777657990396,"version":"3.51.4"},"reference-count":27,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,18]],"date-time":"2021-04-18T00:00:00Z","timestamp":1618704000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SAICT-45-2017-POCI-01-0145-FEDER-029112\u2014539 PTDC\/EEI-EEE\/29112\/2017"],"award-info":[{"award-number":["SAICT-45-2017-POCI-01-0145-FEDER-029112\u2014539 PTDC\/EEI-EEE\/29112\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>Uninterruptible Power Supplies (UPS) have been demonstrated to be the key technology in feeding either single- and three-phase loads in a wide range of critical applications, such as high-tier datacenters and medical facilities. To increase the overall system power capacity and resilience, UPS systems are usually connected in parallel. When UPS systems are parallel connected, a circulating current can rise, inhibiting correct system operation. Moreover, having a controlled load power distribution is another fundamental requirement in paralleled UPS systems. However, strategies to ensure these two topics have not been explored to date for UPS systems with a load-side neutral connection. This paper proposes an innovative Finite Control Set Model Predictive Control (FCS-MPC) strategy that ensures circulating current elimination and controlled load power distribution for paralleled UPS systems that use an additional inverter leg for load neutral point connection. Additionally, a system topology based on two parallel-connected UPS systems that can simultaneously supply single- and three-phase critical loads is proposed. Experimental results show the effectiveness and robustness of the proposed control techniques even when different types of loads are connected to the UPS systems.<\/jats:p>","DOI":"10.3390\/en14082270","type":"journal-article","created":{"date-parts":[[2021,4,18]],"date-time":"2021-04-18T22:15:13Z","timestamp":1618784113000},"page":"2270","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Model Predictive Control for Paralleled Uninterruptible Power Supplies with an Additional Inverter Leg for Load-Side Neutral Connection"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9760-1261","authenticated-orcid":false,"given":"Tiago","family":"Oliveira","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2176-9658","authenticated-orcid":false,"given":"Lu\u00eds","family":"Caseiro","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7529-5670","authenticated-orcid":false,"given":"Andr\u00e9","family":"Mendes","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9651-8925","authenticated-orcid":false,"given":"S\u00e9rgio","family":"Cruz","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3771-2306","authenticated-orcid":false,"given":"Marina","family":"Perdig\u00e3o","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, University of Coimbra\u2014Pole 2, P-3030-290 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1875","DOI":"10.1109\/TIE.2009.2015750","article-title":"Model Predictive Control of an Inverter With Output LC Filter for UPS Applications","volume":"56","author":"Cortes","year":"2009","journal-title":"IEEE Trans. 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