{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T06:24:46Z","timestamp":1770963886545,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T00:00:00Z","timestamp":1770422400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013367","name":"Universidad Tecnol\u00f3gica de Pereira","doi-asserted-by":"publisher","award":["6-23-5"],"award-info":[{"award-number":["6-23-5"]}],"id":[{"id":"10.13039\/501100013367","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013367","name":"Universidad Tecnol\u00f3gica de Pereira","doi-asserted-by":"publisher","award":["6-25-5"],"award-info":[{"award-number":["6-25-5"]}],"id":[{"id":"10.13039\/501100013367","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>The Four-Leg Three-Phase Voltage Source Inverter (4LVSI) is a versatile solution for integrating renewable energy sources (RESs) into distribution networks, as it compensates unbalanced voltages and currents while providing a path for zero-sequence components. Accurate current control is essential to ensure power quality and reliable operation under these conditions. Conventional controllers such as proportional\u2013integral, resonant, or feedback-linearization methods achieve acceptable tracking under static dc-link conditions, but their performance degrades when dc-link voltage dynamics arise due to renewable-source fluctuations. This paper proposes a data-driven model reference neural control (MRNC) strategy for a four-leg inverter connected to RESs, explicitly accounting for dc-link voltage variations. The proposed controller reformulates the classical Model Reference Adaptive Control (MRAC) as a lightweight single-layer neural network whose adaptive weights are updated online using the Recursive Least Squares (RLS) algorithm. In this framework, the dc-link variations are not modeled explicitly but are implicitly learned through the data-driven adaptation process, as their influence is captured in the neural network regressors formed from real-time input\u2013output measurements. This allows the controller to continuously identify the inverter dynamics and compensate the effect of dc-link fluctuations without requiring additional observers or prior modeling. The proposed approach is validated through detailed time-domain simulations and real-time Hardware-in-the-Loop (HIL) experiments implemented at a 10 kHz switching frequency. The results indicated that the RLS-based MRNC controller achieved the lowest steady-state current error, reducing it by approximately 1.85% and 1% compared to the Proportional-Resonant (PR) and One-Step-Ahead (OSAC) controllers, respectively. Moreover, under dc-link voltage variations, the proposed controller significantly reduced the current overshoot, achieving decreases of 5.9 A and 6.36 A relative to the PR controller.<\/jats:p>","DOI":"10.3390\/info17020171","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T08:15:54Z","timestamp":1770624954000},"page":"171","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Data-Driven Model Reference Neural Control for Four-Leg Inverters Under DC-Link Voltage Variations"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0084-2721","authenticated-orcid":false,"given":"Ana J.","family":"Mar\u00edn-Hurtado","sequence":"first","affiliation":[{"name":"Research Group in Power Electronics, Electrical Engineering Department, Universidad Tecnol\u00f3gica de Pereira, Pereira 660003, Colombia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0061-4278","authenticated-orcid":false,"given":"Andr\u00e9s","family":"Escobar-Mej\u00eda","sequence":"additional","affiliation":[{"name":"Research Group in Power Electronics, Electrical Engineering Department, Universidad Tecnol\u00f3gica de Pereira, Pereira 660003, Colombia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6228-2731","authenticated-orcid":false,"given":"Eduardo","family":"Giraldo","sequence":"additional","affiliation":[{"name":"Research Group in Automatic Control, Electrical Engineering Department, Universidad Tecnol\u00f3gica de Pereira, Pereira 660003, Colombia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1109\/TIA.2016.2613074","article-title":"Enhanced frequency response strategy for a PMSG-based wind energy conversion system using ultracapacitor in remote area power supply systems","volume":"53","author":"Tan","year":"2017","journal-title":"IEEE Trans. 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