# Investigation of Failures during Commissioning and Operation in Photovoltaic Power Systems
###### Abstract  
Considering global warming and environmental problems, the importance of renewable energy sources is increasing day by day. In particular, the effects of wind and solar power, which are variable renewable power sources, on the power system necessitate their evaluation in terms of the reliability of the power system. Photovoltaic panels, which enable the conversion of solar power into electrical power with semiconductors, have started to take an important place in global energy investments today. Photovoltaic power plants increase the demand for this energy source with continuous energy conversion depending on sunshine duration and radiation intensity. Among the renewable energy sources, the most easily utilized energy source, regardless of geographical conditions, is the sun. To prevent the energy production of PV power plants from being interrupted, it is necessary to address and analyze all kinds of faults that will affect power production in order to increase the reliability of the system. Academic studies in this field are generally grouped under two topics: classification of faults or modeling of electrical faults. Based on this, in this study, the problems that occur during the installation and operation of photovoltaic systems are classified, and the relevant faults are modeled and simulated in MATLAB Simulink version 23.2 (R2023b). Thus, a scientific approach to the problems of photovoltaic power plant operating conditions has been gained, which will be the basis for academic studies. commissioning; failure; fault classification; open circuit; photovoltaic; short circuit; MATLAB Simulink 20242083144208314420831442083144208314420831442083144208314208314420831420831442083  
Any effect that reduces the output voltage of a PV power plant can be called a fault [4]. Depending on how long a problem lasts, it might be classified as either temporary or permanent. The most widely used heads for categorizing electrical failures in PV power plants were investigated by [PERSON] et al. in [4]. The alternating current (AC) side and direct current (DC) side faults are the two primary categories under which the faults were addressed in their study. In [5], [PERSON] et al. categorized the faults encountered in PV power plants into three sections, including AC and DC faults as well as faults encountered during the data-gathering stage for the control system. PV power plant electrical faults, specifically earth, phase-to-phase, and PV arc faults, were analyzed in the upper headings and categorized into subgroups based on the causes of the faults within each heading in [6]. PV panel electrical failures were modeled using MATLAB/Simulink software by [PERSON] et al. in [7]. Compared with previous studies, [PERSON] et al. 's [8] approach to problems in PV power plants is distinct and comprehensive. Defects were divided into three categories: physical, electrical, and environmental. A comprehensive collection of electrical issues was created by classifying them into categories such as PV string failures and inverter faults. Subsequently, [PERSON]'s model was used to analyze the fault classification technique developed for the PV plant using the MATLAB/Simulink application [5]. In [PERSON] et al. 's study [9], machine learning techniques were used in PV power plants to identify problems. In a study by [PERSON] et al. [10], using a simulation tool, a model was made for a typical PV power plant, and the model's response to lightning strikes was investigated. [PERSON] et al. [11] reported that while photovoltaic power plants have a low failure rate, the popular \"Install and Forget\" approach to them is incorrect. Photovoltaic power plants are susceptible to a variety of failure modes. The categorization of failures based on their types and the modeling of their potential consequences are crucial for application convenience and as a resource for academic works in the future.