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Modeling and Experimental Validation of a Low-Cost Radiation Sensor Based on the Photovoltaic Effect for Building Applications
摘要： The energy consumed to cool buildings is very elevated and solar gains represent a high percentage of these cooling loads. To minimize the thermal load it is necessary to control external shading systems. This control requires continuous measurement of solar radiation in different locations of the building. However, for such applications the use of conventional irradiance sensors increases the cost and reduces the profitability of the installation. This paper is focused on the development, modeling, and experimental validation of low cost irradiation sensors based on photovoltaic effect in order to reduce the costs of dynamic external shading devices and to improve the profitability of the system. With this proposal, firstly, small commercial photovoltaic cells have been adapted for use as an irradiation measurement device. Subsequently, quasi-stationary and continuous experimental measurements of these silicon cells, facing south and installed horizontally, have been carried out in Jaén (Spain) in 2009 and 2010. Finally, a nonlinear multiparameter function has been developed to evaluate the irradiance using the electric current generated by the cell, cell temperature, ambient temperature, and absolute humidity. A favorable agreement between the model predictions and experimental data has been observed with a coefficient of determination around 0.996 for all cells.
关键词： thermal drift,solar radiation,photovoltaic,building,solar cells,irradiance estimation
更新于2025-09-23 15:19:57
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Probabilistic Generation Model of Solar Irradiance for Grid Connected Photovoltaic Systems Using Weibull Distribution
摘要： Around the world, countries are integrating photovoltaic generating systems to the grid to support climate change initiatives. However, solar power generation is highly uncertain due to variations in solar irradiance level during different hours of the day. Inaccurate modelling of this variability can lead to non-optimal dispatch of system resources. Therefore, accurate characterization of solar irradiance patterns is essential for effective management of renewable energy resources in an electrical power grid. In this paper, the Weibull distribution based probabilistic model is presented for characterization of solar irradiance patterns. Firstly, Weibull distribution is utilized to model inter-temporal variations associated with reference solar irradiance data through moving window averaging technique, and then the proposed model is used for irradiance pattern generation. To achieve continuity of discrete Weibull distribution parameters calculated at different steps of moving window, Generalized Regression Neural Network (GRNN) is employed. Goodness of Fit (GOF) techniques are used to calculate the error between mean and standard deviation of generated and reference patterns. The comparison of GOF results with the literature shows that the proposed model has improved performance. The presented model can be used for power system planning studies where the uncertainty of different resources such as generation, load, network, etc., needs to be considered for their better management.
关键词： solar power generation,irradiance patterns,Weibull distribution
更新于2025-09-23 15:19:57
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Switched Capacitor-Coupled Inductor DCa??DC Converter for Grid-Connected PV System using LFCSO-Based Adaptive Neuro-Fuzzy Inference System
摘要： In this paper, the Levy °ight-based chicken swarm optimization (LFCSO) is proposed to follow the highest power of grid-joined photovoltaic (PV) framework. To analyze the grid-associated PV framework, the characteristics of current, power, voltage, and irradiance are determined. Because of the low yield voltage of the source PV, a big advance up converter with big productivity is required when the source PV is associated with the matrix power. A tale great advance up converter dependent on the exchanged capacitor and inductor is illustrated in this paper. The LFCSO algorithm with the adaptive neuro-fuzzy inference system is used to generate the control pulses of the transformer-coupled inductor DC–DC converter-less switched capacitor. While using the switched capacitor-coupled inductor, the voltage addition is expanded in the DC–DC converter and the power of PV is maximized. Here, the normal CSO algorithm is updated with the help of Levy °ight functions to generate optimal results. To get the accurate optimal results, the output of the proposed LFCSO algorithm is given as the input of the ANFIS technique. After that, the optimal results are generated and they provide the pulses for the system. The working guideline is analyzed and the voltage addition is derived with the utilization of the proposed technique. From that point forward, it predicts the exact maximum power of the converter according to its inputs. Under the variety of solar irradiance and partial shading conditions (PSCs), the PV system is tested and its characteristics are analyzed in di?erent time instants. The proposed LFCSO with ANFIS method is actualized in Simulink/MATLABstage, and the tracking executing is examined with a traditional method such as genetic algorithm (GA), perturb and observe (P&O) technique–neuro-fuzzy controller (NFC) and fuzzy logic controller (FLC) technique.
关键词： irradiance,Levy °ight-based chicken swarm optimization algorithm,partial shading conditions,transformer-less switched capacitor-coupled inductor DC–DC converter voltage,current,power,grid-connected PV,GA-NFC and FLC methods
更新于2025-09-23 15:19:57
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Simulation and experimental validation of fast adaptive particle swarm optimization strategy for photovoltaic global peak tracker under dynamic partial shading
摘要： The P–V characteristics of PV array has one peak under uniformly distributed irradiances. Whereas, there are many peaks in the P–V curve when the irradiance is not uniformly distributed over the PV array which is called “partial shading conditions (PSCs)”. Due to its robustness in tracking the global peak (GP) of many applications, metaheuristic techniques are used as maximum power point tracker (MPPT) for the PV system under PSCs. Particle swarm optimization (PSO) has been used in this paper for this purpose. Three problems associated with the PSO have been solved in this paper using a novel fast adaptive PSO (APSO) strategy. The problem of long convergence time has been solved by updating starting values of the duty ratio of the DC-DC boost converter to be at the anticipated places of peaks. This modification reduces the convergence time and avoids the premature convergence. The problem of stored GP in the memory will prevent the PSO from capturing the current GP in case of it is lower than the stored one. This problem is solved in this paper by updating the memorized GP with the current maximum power when it is not changed for two successive iterations. The third problem of sudden change in PSCs is solved by using the updated values of duty ratio at anticipated peaks as initial values for particles. To the best of the authors’ knowledge, these problems have not been discussed or solved before in the literature. A comparison to the state-of-the-art random initialization PSO strategy shows the superiority of the proposed APSO technique in terms of tracking speed and dynamic GP tracking. The results obtained from the simulation of this strategy proved its superiority in always tracking the GP under dynamic PSCs change.
关键词： Partial shading conditions,Photovoltaic,Dynamic irradiance change,Maximum power point tracker,Global peak,Adaptive particle swarm optimization
更新于2025-09-23 15:19:57
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A Novel Method for Optimizing Power Efficiency of a Solar Photovoltaic Device
摘要： Most recently, photovoltaic energy has made an incredible technological advancement for the forthcoming decades towards mitigating the ever-increasing energy demand worldwide through generating electric power. Present paper proposes a novel solar photovoltaic (SPV) device model that achieves optimal power efficiency from simulation and graphical performance analysis of SPV device characteristics. First of all, power as well as current performances is compared for varying irradiance and temperatures circumstances. Then, output current characteristics of the SPV device for the proposed as well as existing model with variable temperatures is plotted. Later, power versus voltage performances of a SPV device for the proposed model with varying irradiance and temperature criterions is compared. Finally, power–voltage characteristics are plotted graphically for the existing as well as proposed SPV device model that achieves significant amount of output power for the proposed model than the existing model and optimal power efficiency is obtained for the novel SPV device model.
关键词： Power–voltage,Irradiance,Solar photovoltaic (SPV),Optimal power efficiency (OPE),Photovoltaic (PV)
更新于2025-09-23 15:19:57
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[IEEE 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Sydney, Australia (2018.11.21-2018.11.23)] 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Analysis of the effects of multiple reflection paths on high speed VLC system performance
摘要： In the recent past, research in visible light communication (VLC) has gained a lot interest due to its distinct characteristics in supporting high-speed data transmission and illumination simultaneously. To implement a reliable VLC system, few parameters have to be considered for communication channels such as distance between transmitter and receiver, data rate, line of sight (LOS) and non-line of sight (NLOS) communication paths, signal power and delay of the channel. In this paper, we designed and simulated a LOS and NLOS multipath VLC model using single and multiple LEDs. Basic on-off keying (OOK) modulation scheme and available conventional LED configuration have been considered to analyze the effects of field of view (FOV) and the reflection of the light signal on received power level. Moreover, BER and quality of transmission were measured for single and multipath transmissions considering distance, incident and irradiance angles.
关键词： BER,LED refraction,Visible Light Communication,multi-channel,FOV,irradiance and incident angle
更新于2025-09-19 17:15:36
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Broadband dependence of atmospheric transmissions in the UV and total solar radiation
摘要： Atmospheric broadband transmissions of clouds, aerosols, and ozone in the erythemally weighted ultraviolet (EUV, 290–320 nm), total (spectrally integrated) ultraviolet (TUV, 290–363 nm), and total global solar (GS, 305–2800 nm) spectral regions were analysed with ground-based measurements in Seoul, Korea (37.57°N, 128.98°E) from March 2004 to February 2013. The annual average total transmission expressed as a fraction of the clear-sky irradiance was 77.6% in the EUV, 73.6% in the TUV, and 72.0% in the GS spectral regions. The corresponding values for cloud transmission were 78.4%, 73.9%, and 71.7%. In overcast cloudy conditions, atmospheric transmission was reduced by 45.9%, 50.2%, and 56.6% in the three spectral regions, respectively, indicating the dominant effect of clouds. Aerosol and ozone transmissions had almost the same annual average. Annual average atmospheric transmission effectively decreases with increasing wavelength from EUV to GS regions. However, we found that there was a difference in wavelength dependence of atmospheric transmission for monthly averages, which seems related to the monthly variation of total column ozone (TCO), aerosol, and cloud amount. It is also found that there is a critical value of TCO (TCO =370 DU) for the wavelength dependence of transmission. Higher ozone amount than this turnaround value can cause an increase in transmission from the EUV to GS regions. The monthly wavelength-dependent effects may be attributable more to the different climatological characteristics of the TCO rather than aerosols and clouds.
关键词： modification factor,Brewer spectrophotometer,ultraviolet,surface solar irradiance,transmission
更新于2025-09-19 17:15:36
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Significant decrease of photovoltaic power production by aerosols. The case of Santiago de Chile
摘要： Santiago de Chile frequently suffers from atmospheric pollution that contributes to the decrease of solar irradiance on the surface, leading to losses in the energy output of photovoltaic systems. In this study, a simple model is used to estimate the effect of aerosols on the solar irradiance over the city throughout the year, using as input AERONET sunphotometer data and other in-situ measurements. The results show reductions of 3.5% and 14.1% for global horizontal and direct normal irradiance respectively and an increase of 35.4% for diffuse horizontal irradiance between the actual condition in Santiago and a hypothetical atmosphere free of aerosols. These effects translate approximately to an annual difference in the energy output of -7.2% and -8.7% for monocrystalline and amorphous silicon PV technologies respectively, and an annual difference of -16.4% for a CPV technology, showing that aerosols can have a significant effect on the photovoltaic energy production.
关键词： Solar irradiance,AERONET,Chile,Air pollution,Santiago,Aerosols,Photovoltaics
更新于2025-09-19 17:13:59
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Number of maximum power points in photovoltaic arrays during partial shading events by clouds
摘要： This article presents a study of the number of maximum power points (MPPs) of photovoltaic (PV) module arrays during partial shading events by clouds. Around 9000 shadow edges were identified in measured irradiance data, and the electrical characteristics of 250 to 500 PV module arrays with different configurations were studied during the irradiance changes. It was found that most of the partial shading events caused by clouds do not cause multiple MPPs for PV arrays, even for a moment. The number of MPPs was found to decrease with the increasing number of parallel-connected PV strings, but to increase strongly with the increasing length of the strings. According to the results, the use of a total-cross-tied electrical PV array configuration leads to worse system performance compared to a simple series-parallel configuration during partial shading events. Dark shadows with sharp edges moving parallel to the PV strings caused the largest MPP numbers, up to 20. The results show that energy losses due to operation at a local MPP instead of the global one during partial shading events by clouds have only a minor effect on the total energy production of PV arrays.
关键词： Maximum power point,Photovoltaic Array,Partial shading,Irradiance change,Photovoltaic power generation
更新于2025-09-19 17:13:59
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Novel Open-Circuit Photovoltaic Bypass Diode Fault Detection Algorithm
摘要： In this article, a novel photovoltaic (PV) bypass diode fault detection algorithm is presented. The algorithm consists of three main steps. First, the threshold voltage of the current–voltage (I–V) curve is obtained using different failure bypass diode scenarios. Second, the theoretical prediction for the faulty regions of bypass diodes is calculated using the analysis of voltage drop in the I–V curve as well as the voltage at maximum power point. Finally, the actual I–V curve under any environmental condition is measured and compared with theoretical predictions. The proposed algorithm has been experimentally evaluated using a PV string that comprises three series-connected PV modules, and subtotal of nine bypass diodes. Various experiments have been conducted under diverse bypass diodes failure conditions. The achieved detection accuracy is always greater than 99.39% and 99.74% under slow and fast solar irradiance transition, respectively.
关键词： current–voltage (I–V) curve,Bypass diodes,power loss,fault detection,photovoltaics (PV),solar irradiance
更新于2025-09-19 17:13:59