Citation: Duer, S.; Wo´ zniak, M.; Ostrowski, A.; Pa´ s, J.; Duer, R.; Zajkowski, K.; Bernatowicz, D. Assessment of the Reliability of Wind Farm Device on the Basis of Modeling Its Operation Process. Energies 2023, 16, 142. https:// doi.org/10.3390/en16010142 Received: 30 October 2022 Accepted: 11 November 2022 Published: 23 December 2022 Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). energies Editorial Assessment of the Reliability of Wind Farm Device on the Basis of Modeling Its Operation Process Stanislaw Duer 1, * , Marek Wo´ zniak 2 , Arkadiusz Ostrowski 2 , Jacek Pa´ s 3 , Radoslaw Duer 1 , Konrad Zajkowski 1 and Dariusz Bernatowicz 4 1 Department of Energy, Faculty of Mechanical Engineering, Technical University of Koszalin, 15-17 Raclawicka St., 75-620 Koszalin, Poland 2 Doctoral School, Technical University of Koszalin, 2 Sniadeckich St., 75-620 Koszalin, Poland 3 Faculty of Electronic, Military University of Technology of Warsaw, 2 Urbanowicza St., 00-908 Warsaw, Poland 4 Faculty of Electronic and Informatics, Technical University of Koszalin, 2 Sniadeckich St., 75-620 Koszalin, Poland * Correspondence: stanislaw.duer@tu.koszalin.pl; Tel.: +48-943-478-262 Abstract: The evaluation and analysis of the procedures for determining the dependability of WF wind farm equipment employed in a few publications are this article’s main problems. The publica- tions chosen for review specifically mention investigations into the dependability of WF wind farm machinery. The following topics were the authors’ main areas of analysis: description and review of the techniques used to represent how technical items operate and the selection of the weight of the theoretical ideas of reliability that were used to gauge the dependability of the wind farm equipment under study. The authors of the studied works set out to address a number of significant problems pertaining to the modernization of the management of the WF equipment renewal process. The subjects of the studied works suggest that the established models of the technical object’s operational process are particularly significant in both the theory and practice of the reliability of technical objects. Using Kolmogorov–Chapman equations, models of the WFD operating process that are based on the idea of Markov processes are very helpful for simulation studies. Keywords: wind power plant; reliability; simulation testing; intelligent systems; servicing process; Markov processes; expert system 1. Introduction Complex technical infrastructure, such as wind farm equipment, when employed, loses its functional qualities throughout its operation, and its capacity to carry out the necessary functions (their intended tasks) declines. In the literature, the issue of defining usable capacity is referred to as a functional resource. The diminishing reliability of technical objects, including WF wind farm equipment, is likewise closely related to decreasing useful capacity. Age-related changes and the damaging impacts of internal (temperature, pressure, etc.) and external elements are the main causes of technical items’ decreasing reliability. As a result, the issue of making continuous and current measurements and assessments of the equipment reliability of wind farms arises. The organization of the renewal of the functional qualities of complicated technological equipment can be made based on knowledge of the existing the reliability of wind farm equipment. The issue is highly complex for technological instruments that continuously carry out their functions and without the option of being taken out of service; these instruments include wind farm equipment, electricity systems, medical systems, and others. The primary research goal stated in the studied articles is now to understand how reliable wind farm equipment is. The following publications [1–4] present the current level of reliability of in-service equipment of wind farms (WFs) and other sophisticated technical facilities, which is an ongoing research issue. Energies 2023, 16, 142. https://doi.org/10.3390/en16010142 https://www.mdpi.com/journal/energies