The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Bülent Oral - One of the best experts on this subject based on the ideXlab platform.
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Spectrum Measurement of Variable Irradiance Controlled LED-Based Solar Simulator
International Journal of Renewable Energy Research, 2020Co-Authors: Vedat Esen, Bülent Oral, şafak Saglam, Ozge Ceylan EsenAbstract:Efficiency of photovoltaic devices are based on testing all equipment and systems used to produce devices in a healthy way, from electrical and optical points of view. Considering that photovoltaic devices which enable the generation of electric energy from Solar energy as a renewable energy source are widely used Solar Simulators should be utilized to provide actual daylight spectrum distributions. The most considerable component of Solar Simulators in photovoltaic device research is the light sources they use. Due to their advantages over conventional light sources, such as compactness, low power consumption, and low cost, research and studies on Solar Simulators use LEDs took place as an their illumination source. In this study, it is aimed to produce a low-cost Class A Solar simulator with using six different type power LEDs, as specified in the IEC 60904-9 and ASTM E927-05 standards. At the end of the study with 24 power LEDs with six different wavelengths, the spectral match which is one of the three performance criteria of the Solar simulator was obtained as Class A.
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Solar irradiation fundamentals and Solar Simulators
2020Co-Authors: Vedat Esen, şafak Saglam, Bülent OralAbstract:This chapter is prepared for introduction to Solar radiation and Solar Simulators, which are widely used photovoltaic researches. In this study, the fundamentals of Solar radiation and the components of Solar radiation in the atmosphere are briefly expressed. Besides, Solar Simulators used in PV tests are emphasized, classification of Solar Simulators, international standards and light sources are explained in detail. Also, as a case study, it is designed LED-based Solar simulator.
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Light sources of Solar Simulators for photovoltaic devices: A review
Renewable and Sustainable Energy Reviews, 2017Co-Authors: Vedat Esen, Semran Saglam, Bülent OralAbstract:As Solar power usage is increasing nowadays, performance tests have become one of the most important topics in order to guarantee the security of photovoltaic tools. For photovoltaic panels to become efficient, there is need for health testing of all materials and technologies used in the production of the panels in electrical and optical aspects. Thus, when future energy standards are considered, it is imperative to use Solar Simulators that obtain near real sunlight spectrum values. The most important components of Solar Simulators used in photovoltaic panel tests are light sources. In this study, Solar Simulators were classified based on the light sources they use, and their history and technological development were investigated in line with the literature. Within the scope of this study, carbon arc lamps, sodium vapor lamps, argon arc lamps, quartz-tungsten halogen lamps, mercury xenon lamps, xenon arc, xenon flash lamps, metal halide lamps, LED and super continuum laser light sources were investigated. Additionally, to compare spectral deficiency among these light sources and Solar Simulators, multiple light sourced Solar Simulators were also covered under a separate title.
Dahe Gu - One of the best experts on this subject based on the ideXlab platform.
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concentric multilayer model of the arc in high intensity discharge lamps for Solar Simulators with experimental validation
Solar Energy, 2015Co-Authors: Xue Dong, Dahe Gu, Graham J Nathan, Peter J. AshmanAbstract:Abstract High flux Solar Simulators, comprising high-intensity-discharge lamps coupled with elliptical reflectors, have been widely employed to study concentrated Solar thermal energy systems in a controlled manner. However, little information is available of the influence of the assumptions about the properties of the arc on the accuracy of the prediction of the heat flux at the focal plane. This paper presents a concentric multilayer model of the arc that is developed to predict the spatial distribution of the heat flux at the focus. Measurements were performed of both the time-resolved and time-averaged spatial distribution of the discharge arc from a commercial metal halide lamp with a 23 mm spacing between the two electrodes. The efficacy of various alternative simplified approaches to model the arc using a commercial Monte Carlo ray-tracing code were assessed, which include models of cylinder, monopole sphere, dipole-sphere and three types of compounds of these three shapes. These predictions were validated with measurements using a CCD camera and a heat flux gauge, which shows that the predicted profiles from the three compound models agree with the experimental results to similar extent, with no difference in the predicted maximum heat flux and within a difference of 11% for the predicted half-width.
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Time-resolved spectra of Solar Simulators employing metal halide and xenon arc lamps
Solar Energy, 2015Co-Authors: Xue Dong, Peter J. Ashman, Zhiwei Sun, Graham J Nathan, Dahe GuAbstract:The time-resolved spectra of the irradiation emitted from Solar Simulators employing the two types of high-intensity discharge arc lamps that are commonly used in Solar Simulators, i.e. metal halide (here 6. kW) and xenon arc (here 5. kW) lamps, are reported. The lamp emission was recorded by a fast-response photodiode, which reveals that the amplitude of oscillating irradiation intensity from the metal halide lamp is approximately 60% of the peak intensity, while its oscillation frequency is twice of the frequency of the AC power supply, here 100. Hz. The irradiation of the xenon arc lamp is powered by a modulated DC supply to oscillate at 300. Hz, with an amplitude that is found to be only approximately 9% that of the peak intensity. An intensified CCD camera, which was coupled with a spectrometer operating in a range of 350-900. nm, was synchronized with the lamp to provide phase-resolved spectra. The irradiation from the xenon arc lamp was found to be spectrally stable with time; while that from the metal halide lamp varies significantly throughout oscillation cycle, especially at the shorter-wavelengths of below 550. nm. All spectra were calibrated to reveal that the time-averaged spectrum of the simulator with a metal halide lamp matches the Solar spectrum significantly better than does that from a xenon arc lamp. The reflecting surface of polished ellipsoidal reflector was found to reduce the intensity of selected frequency bands by up to 10%, while that from both the polished ellipsoidal reflector and conical concentrator was found to reduce the intensity in selected frequency bands by up to 20%.
Tabea Luka - One of the best experts on this subject based on the ideXlab platform.
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spectral characterization of Solar cells and modules using led based Solar Simulators
Solar Energy Materials and Solar Cells, 2019Co-Authors: Marko Turek, Kai Sporleder, Tabea LukaAbstract:Abstract The failure and loss analysis of Solar cells relies on the precise determination of their electrical performance parameters. Light emitting diodes (LEDs) used as light sources in Solar Simulators provide a number of advantages compared to conventional Xenon-based Solar Simulators. In this work, we present an approach to rapidly measure the quantum efficiency and the reflectivity that takes the spectral broadening of the LEDs fully into account. Our approach does not rely on any specific shape of the spectral peaks and can thus be applied to any type of quasi-monochromatic light source. The two proposed methods yield valuable additional information on the Solar cell performance and material properties that cannot be obtained by conventional Solar Simulators. Using LED Solar Simulators, they are completely in-line capable as they can be performed in less than one second.
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rapid testing of external quantum efficiency using led Solar Simulators
Energy Procedia, 2015Co-Authors: Tabea Luka, Stefan Eiternick, Marko TurekAbstract:Abstract A new generation of Solar Simulators is based on light emitting diode illumination sources. These measurement systems offer the opportunity to adjust the light spectrum as close as possible to the AM1.5G reference spectrum. Additionally, they provide the technical basis to combine power measurements with a spectral resolved analysis. Such an application is the determination of the quantum efficiency, which results in valuable additional cell information such as front and rear surface recombination, diffusion length, or emitter dead layer thickness. In this work, a fast method to determine the external quantum efficiency (EQE) of a Solar cell using a LED Solar simulator is presented. The measurement time of our LED-EQE approach could be reduced to less than half a second as no mechanical parts such as monochromators are involved. Due to the finite spectral band-width of the LEDs an adapted data analysis approach has been developed, which leads to results that show excellent agreement with standard EQE measurements.
Anon Namin - One of the best experts on this subject based on the ideXlab platform.
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determination of Solar cell electrical parameters and resistances using color and white led based Solar Simulators with high amplitude pulse input voltages
Renewable Energy, 2013Co-Authors: Anon Namin, C Jivacate, Dhirayut Chenvidhya, K Kirtikara, Jutturit ThongpronAbstract:Advances in LEDs allow construction of LED Solar Simulators for characterization of Solar cells at moderate costs. Four single-color LED Simulators and one multi-color LED Simulators are constructed. High irradiance is obtained by employing high pulsing voltages to LEDs. Using the Simulators electrical parameters and resistances of Solar cell are made. Applying correction methods recommended in the IEC 891 Standard, results from the red and blue LED Simulators and the Class AAA simulator are in good agreement.
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construction of tungsten halogen pulsed led and combined tungsten halogen led Solar Simulators for Solar cell characterization and electrical parameters determination
International Journal of Photoenergy, 2012Co-Authors: Anon Namin, C Jivacate, Dhirayut Chenvidhya, K Kirtikara, Jutturit ThongpronAbstract:- characterization of Solar cells is generally done under natural sunlight or Solar Simulators operating in either a continuous mode or a pulse mode. Simulators are classified on three features of irradiance, namely, spectral match with respect to air mass 1.5, spatial uniformity, and temporal stability. Commercial Solar Simulators use Xenon lamps and halogen lamps, whereas LED-based Solar Simulators are being developed. In this work, we build and test seven Simulators for Solar cell characterization, namely, one tungsten halogen simulator, four monochromatic (red, green, blue, and white) LED Simulators, one multicolor LED simulator, and one tungsten halogen-blue LED simulator. The seven Simulators provide testing at nonstandard test condition. High irradiance from Simulators is obtained by employing elevated supply voltage to tungsten halogen lamps and high pulsing voltages to LEDs. This new approach leads to higher irradiance not previously obtained from tungsten halogen lamps and LEDs. From - curves, electrical parameters of Solar cell are made and corrected based on methods recommended in the IEC 60891 Standards. Corrected values obtained from non-STC measurements are in good agreement with those obtained from Class AAA Solar simulator.
Jutturit Thongpron - One of the best experts on this subject based on the ideXlab platform.
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determination of Solar cell electrical parameters and resistances using color and white led based Solar Simulators with high amplitude pulse input voltages
Renewable Energy, 2013Co-Authors: Anon Namin, C Jivacate, Dhirayut Chenvidhya, K Kirtikara, Jutturit ThongpronAbstract:Advances in LEDs allow construction of LED Solar Simulators for characterization of Solar cells at moderate costs. Four single-color LED Simulators and one multi-color LED Simulators are constructed. High irradiance is obtained by employing high pulsing voltages to LEDs. Using the Simulators electrical parameters and resistances of Solar cell are made. Applying correction methods recommended in the IEC 891 Standard, results from the red and blue LED Simulators and the Class AAA simulator are in good agreement.
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construction of tungsten halogen pulsed led and combined tungsten halogen led Solar Simulators for Solar cell characterization and electrical parameters determination
International Journal of Photoenergy, 2012Co-Authors: Anon Namin, C Jivacate, Dhirayut Chenvidhya, K Kirtikara, Jutturit ThongpronAbstract:- characterization of Solar cells is generally done under natural sunlight or Solar Simulators operating in either a continuous mode or a pulse mode. Simulators are classified on three features of irradiance, namely, spectral match with respect to air mass 1.5, spatial uniformity, and temporal stability. Commercial Solar Simulators use Xenon lamps and halogen lamps, whereas LED-based Solar Simulators are being developed. In this work, we build and test seven Simulators for Solar cell characterization, namely, one tungsten halogen simulator, four monochromatic (red, green, blue, and white) LED Simulators, one multicolor LED simulator, and one tungsten halogen-blue LED simulator. The seven Simulators provide testing at nonstandard test condition. High irradiance from Simulators is obtained by employing elevated supply voltage to tungsten halogen lamps and high pulsing voltages to LEDs. This new approach leads to higher irradiance not previously obtained from tungsten halogen lamps and LEDs. From - curves, electrical parameters of Solar cell are made and corrected based on methods recommended in the IEC 60891 Standards. Corrected values obtained from non-STC measurements are in good agreement with those obtained from Class AAA Solar simulator.