Sustainable Development Goal "Goal 7: Affordable and Clean Energy" ile LEE- Fizik Mühendisliği Lisansüstü Programı'a göz atma
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ÖgeEffects of solar radiation and neutron, gamma material intereaction effects on the solar cells/modules/panels(Graduate School, 2021-12-17) Demirel Turna, İnal Begüm ; Er, Zuhal ; 509162103 ; Physics EngineeringThis thesis study covers the examination of the performance and degradation conditions of photovoltaic cells/modules/panels that convert solar radiation into electrical energy in case of exposure to solar radiation and nuclear factors (neutron and gamma irradiation) in laboratory and outdoor conditions. In this context, with the beginning of this thesis, first of all, the solar radiation for the province of Istanbul, where the performance and degradation experiments of photovoltaic devices will be carried out, was examined and presented to the literature. In these studies, statistical analysis methods were used to examine the accuracy of the models and the most suitable model was determined for the region to be studied. Afterwards, the working principles of the devices are examined and detailed on the basis of physical science in order to understand the effects of both natural conditions and nuclear effects that the photovoltaic cell/module/panels are exposed to on the device performance and to examine the decay structure. There is a manufacturer's datasheet detailing the electrical characteristics of most of the produced photovoltaic cells/modules/panels at standard test condition (STC; 25℃ and 1000W/m2) and/or nominal operating cell temperature (NOCT; 20℃ and 800W/m2). By using the electrical characteristic data in this datasheet, performance and degradation modeling of photovoltaic cells/modules/panels can be performed theoretically. On the other hand, in some cases, the aforementioned data document may contain incomplete data, and even the data document of the produced device cannot be found at all. In this case, it becomes difficult to examine the performance of the device and to make performance predictions under different environmental conditions. Performance modeling of photovoltaic cells/modules/panels, which is one of the main objectives of this thesis; It was carried out by using the Single Diode Model (SDM), which is frequently used in the literature, and the Double Diode Model (DDM), which is rarely used in the literature, both in the absence of a datasheet or in the absence of a datasheet. The aforementioned theoretical study was firstly carried out by producing sub-models containing interconnected block structures on the MATLAB/Simulink platform and as a result of the merging of the sub-models, with the representation of the photovoltaic device. In the system; with the definition of the ambient conditions, which are the input data, the electrical characteristic output data that the photovoltaic device will show under these ambient conditions has been examined. Simulink study was performed for both SDM and DDM. There are electrical characteristic parameters of the photovoltaic device, which are not available in the manufacturer's datasheet, but have an important place in the evaluation of photovoltaic device performance. These parameters are; photocurrent, ideality factor, saturation current and resistance values. For performance and degradation evaluations, these parameters should be derived in line with the available data. By available data is meant manufacturer data sheet and/or experimental data. In cases where the manufacturer's datasheet is available, with the new photovoltaic device model created on the Simulink platform, firstly the electrical characteristic parameters of the device are derived, and then the electrical data (current, voltage, power) produced by the photovoltaic device under the requested ambient conditions are turned into a program output for performance and degradation analysis. The slope method and/or the simplified open method were used in cases where the manufacturer's data sheet was missing. In this case, theoretical analyzes were carried out with the performance program created with a set of codes on MATLAB. These studies have been carried out for different photovoltaic type devices. Obtained results were compared with experimental data. Both the Simulink model and the MATLAB program result documents created with this doctoral thesis showed that; the theoretically produced performance result for the determined environmental conditions is more compatible with the experimental results carried out within the scope of this thesis in the Double Diode Model compared to the Single Diode Model. As mentioned above, the performance evaluation of photovoltaic cells/modules/panels was also carried out experimentally within the scope of this thesis. The performance of 10W Monocrystalline and 7W Polycrystalline Photovoltaic Modules available in Zuhal ER's Laboratory at ITU Faculty of Arts and Sciences, Fluke Ti90_9Hz Thermal Camera also available within Zuhal ER's Laboratory, and some of the experiments were carried out with the Seaward PV200 Solar PV Test Device and Solar Survey 200R, which were purchased with the project support of the ITU Scientific Research Projects Unit, which is affiliated with the doctoral thesis, with the project number 41722. Performance and degradation effects of environmental factors on photovoltaic modules, which is one of the main objectives of this doctoral thesis, were determined with these devices. The electrical characteristics of the photovoltaic modules with the PV200 Solar PV Test Device and the solar radiation, ambient temperature, photovoltaic module surface temperature were determined with the Solar Survey 200R. It has been seen that the open circuit voltage has increased over time due to the overheating caused by the deterioration of the modules. On the other hand, the surface temperature of the photovoltaic module and extremely hot regions, which are indicators of degradation, were observed and determined with the Fluke Ti90_9Hz Thermal Camera. Performance and degradation evaluations of photovoltaic devices within five years were determined by the laboratory facilities of Zuhal Er, as well as the maximum power determination and performance experiments carried out at the Turkish Standards Institute (TSE). As a result of the experiments carried out at TSE, it was observed that the maximum power values obtained from the modules decreased with the effect of environmental conditions. Experimental studies in addition to the above-mentioned modules, performance and degradation tests of a total of 20 modules, including 1.5W monocrystalline and polycrystalline photovoltaic modules, were carried out. As can be seen, the modules have very low power values compared to the modules mentioned above. The power measurement ranges of the Seaward PV200 Solar PV Test Device, which was purchased with the project support of ITU Scientific Research Projects Unit 41722, is between 5W and 15kW. Therefore, it could not be able to use in the electrical characteristic determination of 1.5W photovoltaic modules. In this case, measuring devices have been produced for the modules that are intended to be examined within the scope of the thesis. Arduino device, which is a microcontroller used in various projects and studies in recent years, has been used for the aforementioned purpose. On the other hand, sensors that determine current, voltage, ambient humidity and temperature are used. The communication protocol called SPI (Serial Peripheral Interface) between the sensors and the Arduino, in other words, the data connection standard starts the operation of the data current sensor and the data flow is provided. Thus, the measurement is started with the Arduino signal and the obtained data is transferred to the SD card; it is recorded via the same communication protocol between the Arduino and the SD card module. Thus, electrical data is collected and recorded for each photovoltaic module. The code is processed on the Arduino in order to determine the initialization of the created measuring device, the operating range, the data collection frequency and the way the data is recorded and listed. Data are performed every five minutes and during the time the solar radiated module. On the other hand, solar radiation data is collected in line with latitude and longitude information via an online platform. Both solar radiation data and module electricity data were recorded and analyzed on both MATLAB and Excel platforms. The obtained results showed that the modules could not perform a full current-voltage curve as expected because they did not receive radiation at all hours of the day. Mostly, data is collected between the maximum power point and the open circuit voltage. On the other hand, it has been observed that modules of the same structure produce similar results. During these studies, since the system was exposed to the external environment, deteriorations such as dulling of the modules and wear at the junction of the cells were observed. In addition to the determination of the effects of environmental factors on photovoltaic cells/modules/panels, neutron and gamma radiation effects are one of the other important objectives of this doctoral thesis. Neutron and gamma rays. Dr. It was held in Isparta, Süleyman Demirel University, Faculty of Arts and Sciences, with the support of İskender Akkurt. Modules that were not exposed to either solar radiation or neutron & gamma radiation before were exposed to gamma and neutron radiation in two sets. first set; two monocrystalline and 2 polycrystalline modules were exposed to gamma radiation for 30 days. second set; Two monocrystalline and 2 polycrystalline modules were exposed to neutron radiation for 15 days. Afterwards, electricity measurements were made under solar radiation like other modules. The results showed that the modules gave voltage values around the open circuit voltage. On the other hand, while fading occurred on the front surface of both sets of modules, deterioration occurred on the rear surface of the modules exposed only to neutron radiation.
ÖgeRadiation damage measurement of plastic scintillators with silicon photomultipliers using collision data in the CMS hadronic calorimeter experiment(Graduate School, 2023-05-05) Kömürcü, Yıldıray ; Çakır, M. Altan ; 509122120 ; Physics EngineeringIn high energy particle collisions, plastic scintillators are commonly used to detect secondary particles and measure their energy along with silicon photomultipliers to amplify the signal. These detectors deteriorate over time due to irradiation they are exposed to and lose their capacity to detect particles efficiently. In the Compact Muon Experiment (CMS) experiment at CERN, hadronic calorimeter is equipped with passive absorbers, plastics scintillators and silicon photomultipliers. In 2017 and 2018, in the data taking periods, in Large Hadron Collider (LHC) two proton beams traveling at opposite directions at energies 6.5TeV are collided and outgoing particles are detected at two detector locations (CMS and ATLAS) along the accelerating ring. In the CMS experiment, energy response obtained from plastic scintillators are monitored in hadronic endcap calorimeter throughout the year and signal drop is measured with collision data, a method also known as in-situ measurement. Energy response of the detector can be monitored with precision in cellular level in longitudinal and azimuthal directions. Signal drop is compared with the results obtained by alternative methods such as laser method. These results not only give insights about the life time of plastic scintillators and silicon photomultipliers but also show their response to dose and dose rate effects. They also provide prospects for future upgrades. The results are used to calibrate the energy values of the collision events for precision measurements and are an integral part of the experiment. We provide the full results of our analysis.