{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T11:59:02Z","timestamp":1766491142913,"version":"3.48.0"},"reference-count":24,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,22]],"date-time":"2025-12-22T00:00:00Z","timestamp":1766361600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Electronics"],"abstract":"<jats:p>This paper presents a high-efficiency wireless power transfer (WPT) architecture employing a resonant inductive coupling to power smart sensor nodes in remote or sealed environments, where conventional power delivery is unfeasible. The system integrates a photovoltaic (PV) energy source with a step-down DC-DC converter based on the LM2596 buck regulator to adjust the voltage from the PV. The proposed conditioned power system supplies the entire electronic circuit consisting of a PWM modulator based on an NE555, which drives an IR2110 gate driver connected to a Class D power amplifier. The amplifier excites a pair of high-Q resonant coils designed for mid-range inductive coupling. On the receiver side, the inductively coupled AC signal is rectified and regulated through an AC-DC conversion stage to charge a secondary energy storage unit. The design eliminates the need for physical electrical connections, ensuring efficient, contactless energy transfer. The proposed system operates at a resonant frequency of 24.46 kHz and achieves up to 80% transmission efficiency at a distance of 113 mm. The receiver provides a regulated DC output between 4.80 V and 4.97 V, sufficient to power low-consumption smart sensors.<\/jats:p>","DOI":"10.3390\/electronics15010033","type":"journal-article","created":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T11:30:18Z","timestamp":1766489418000},"page":"33","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Design and Implementation of a Resonant Inductive Wireless Power Transfer System Powered by a Class D Amplifier for Smart Sensors in Inaccessible Environments"],"prefix":"10.3390","volume":"15","author":[{"given":"Anouar","family":"Chebbi","sequence":"first","affiliation":[{"name":"Electrical Department, LISIER, University of Tunis, 5Av. Taha Hussein, Montfleury, Tunis 1008, Tunisia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7511-9474","authenticated-orcid":false,"given":"Amira","family":"Haddouk","sequence":"additional","affiliation":[{"name":"Electrical Department, LISIER, University of Tunis, 5Av. Taha Hussein, Montfleury, Tunis 1008, Tunisia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6640-8955","authenticated-orcid":false,"given":"Vitor","family":"Monteiro","sequence":"additional","affiliation":[{"name":"Department of Industrial Electronics, ALGORITMI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9195-1239","authenticated-orcid":false,"given":"Jo\u00e3o L.","family":"Afonso","sequence":"additional","affiliation":[{"name":"Department of Industrial Electronics, ALGORITMI, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"given":"Hfaiedh","family":"Mechergui","sequence":"additional","affiliation":[{"name":"Electrical Department, LISIER, University of Tunis, 5Av. Taha Hussein, Montfleury, Tunis 1008, Tunisia"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Pahlavan, S., Shooshtari, M., and Jafarabadi Ashtiani, S. (2022). 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