{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,15]],"date-time":"2026-08-15T03:35:15Z","timestamp":1786764915397,"version":"3.56.0"},"reference-count":23,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,13]],"date-time":"2023-01-13T00:00:00Z","timestamp":1673568000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper describes the implementation of a parameter observer (PO) intended to estimate the capacitance and equivalent serial resistance of a capacitor (ESR). The implemented observer consists of a dynamic second-order discrete-time system. The input signal of the observer is the voltage at the terminals of the capacitor measured during its discharge across a variable resistance in two steps. The implemented observer can be used in quasi-online or offline mode. The theoretical and experimental supporting materials provide a comprehensive picture of the implementation and conditions of use of the PO. The experimental verification was carried out with a microcontroller with Cortex\u00ae-M7 core architecture. The sampling time of the PO was 20 \u03bcs, and the estimation of the parameters was obtained before the end of the discharge of the capacitor. In the cases described in the paper, this means approximately 25 ms. Due to the PO\u2019s capabilities (estimation speed, reduced computational complexity and precision)\u2014proved by the experiments carried out on three electrolytic capacitors of 100 \u03bcF, 220 \u03bcF and 440 \u03bcF\u2014the implementation is of interest for several applications, primarily in the field of power electronic applications.<\/jats:p>","DOI":"10.3390\/s23020948","type":"journal-article","created":{"date-parts":[[2023,1,16]],"date-time":"2023-01-16T05:30:07Z","timestamp":1673847007000},"page":"948","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Implementation of Parameter Observer for Capacitors"],"prefix":"10.3390","volume":"23","author":[{"given":"Corneliu","family":"B\u0103rbulescu","sequence":"first","affiliation":[{"name":"Department of Automation and Applied Informatics, Politehnica University Timi\u0219oara, Bulevardul Vasile P\u00e2rvan, nr. 2, 300223 Timi\u0219oara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dadiana-Valeria","family":"C\u0103iman","sequence":"additional","affiliation":[{"name":"Department of Automation and Applied Informatics, Politehnica University Timi\u0219oara, Bulevardul Vasile P\u00e2rvan, nr. 2, 300223 Timi\u0219oara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5701-9042","authenticated-orcid":false,"given":"Sorin","family":"Nanu","sequence":"additional","affiliation":[{"name":"Department of Automation and Applied Informatics, Politehnica University Timi\u0219oara, Bulevardul Vasile P\u00e2rvan, nr. 2, 300223 Timi\u0219oara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toma-Leonida","family":"Dragomir","sequence":"additional","affiliation":[{"name":"Department of Automation and Applied Informatics, Politehnica University Timi\u0219oara, Bulevardul Vasile P\u00e2rvan, nr. 2, 300223 Timi\u0219oara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6973","DOI":"10.1109\/TPEL.2018.2874997","article-title":"Advances on system identification techniques for DC\u2013DC switch mode power converter applications","volume":"34","author":"Armstrong","year":"2019","journal-title":"IEEE Trans. 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