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Harmonics assessment and mitigation in a photovoltaic integrated network
摘要： This paper presents a comprehensive review of harmonics dominance in PV integrated network. The findings of the review conducted for different scenarios are further supported by the results of an experimental case study exploring the dominance of harmonics in a real time PV integrated microgridunder varying solar irradiance condition. It is concluded that the level of Total Harmonic Distortions (THD) in the power system network varies in different scenarios. Some of the important scenarios are: (i) percentage of PV penetration in distribution network with respect to the types of connected load, (ii) location of PV integration, (iii) effect of harmonic resonance in power network, and (iv) varying power output of PV inverters with varying solar irradiance. A harmonic management system is finally proposed to limit the excessive harmonics in the network under different network conditions. The proposed harmonic management can be used to maintain the THD level within the standard limit and ensures the quality of energy supply to the communities.
关键词： Solar irradiance,Harmonic resonance,Photovoltaic (PV),Total harmonic distortion (THD),Microgrid (MG)
更新于2025-09-16 10:30:52
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Description of short circuit current of outdoor photovoltaic modules by multiple regression analysis under various solar irradiance levels
摘要： Short-circuit current (ISC) values of test photovoltaic (PV) modules, i.e., multi-crystalline silicon, heterostructure-with-intrinsic-thin-layer, single-crystalline silicon back-contact, CuInSe2 (CIS), and CdTe modules, are descripted using multiple regression analysis based on environmental factors (solar irradiance, average photon energy (APE), and module temperature (Tmod)) under several solar irradiance levels. The APE is an index of the solar spectral irradiance distribution. PV module irradiance sensor is used to investigate simultaneous solar irradiance (PVMS), single-crystalline silicon PV module, (IrrTPVMS). It is disclosed that ISC is primarily determined by IrrTPVMS. Error between the estimated ISC and measured ISC of test PV modules is investigated. Consequently, precise ISC description (low error) is obtained when IrrTPVMS is utilized. The more precise description of the ISC for CIS and CdTe PV modules, having the bandgap (Eg) different from PVMS, is realized when adding APE environment factor even under low IrrTPVMS ((cid:1)0 kW/m2), accumulated on both sunny day and cloudy day suggesting the enhancement of investigation opportunity. This is because APE minimizes spectral mismatch error caused by Eg difference between PVMS and test PV module. Moreover, the precision of ISC description is further increased under enhanced IrrTPVMS of (cid:1)0.5 kW/m2 (on sunny day) due to stable solar irradiance.
关键词： Multiple regression analysis,Solar irradiance levels,PV module irradiance sensor,Short-circuit current
更新于2025-09-12 10:27:22
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[IEEE 2019 8th International Conference on Modeling Simulation and Applied Optimization (ICMSAO) - Manama, Bahrain (2019.4.15-2019.4.17)] 2019 8th International Conference on Modeling Simulation and Applied Optimization (ICMSAO) - Harmonic analysis of high penetration level of Photovoltaic generation in distribution network and solution studies
摘要： The high penetration level of Photovoltaic (PV) generation in distribution network reduces carbon emissions but also becomes problematic in terms of network management. Harmonic distortion is the main factor studied in this paper and a typical three-bus distribution network is built in MATLAB/Simulink to understand the harmonics problem. Results show that current harmonics are more vulnerable to fluctuate compared to voltage harmonics. Based on existing harmonic standards, total demand distortion of current (TDDi) is evaluated to estimate maximum PV penetration level at Point of Common Coupling (PCC), and the maximum acceptable TDDi at each bus differs according to specific loading and short-circuit levels. Meanwhile, total harmonic distortion of current (THDi) at inverter outputs represents inverter performance. Instead of assessing at standard test conditions (STC), the impact of irradiance variations is studied. Low irradiance results in an increased THDi of the inverter whilst doesn’t explicitly affect TDDi at PCC. A simple and low-cost solution is proposed to dynamically vary the settings of inverter’s filter elements against irradiance, and harmonic distortion at low irradiance of the inverter is successfully mitigated.
关键词： power system,total demand distortion,total harmonic distortion,irradiance,PV penetration level
更新于2025-09-12 10:27:22
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[IEEE 2019 International Conference on Vision Towards Emerging Trends in Communication and Networking (ViTECoN) - Vellore, India (2019.3.30-2019.3.31)] 2019 International Conference on Vision Towards Emerging Trends in Communication and Networking (ViTECoN) - Modeling and Analysis of Hybrid SIM with L-PPM and MSK over Double Generalized Gamma Distribution in Free Space Optical Communication System
摘要： In this paper, we use Double Generalized Gamma (GG) distribution in turbulence induced fading to model the communication channel under weak, moderate and strong turbulence condition. In order to further improve the performance of Free Space Optical (FSO) Communication system over Double GG distribution, we use Hybrid Subcarrier Intensity Modulation (SIM) with L-Pulse Position Modulation (L-PPM) and Minimum Shift Keying (MSK) and analyze its Bit Error Rate (BER) performance for average received irradiance between -12 dBm and 4 dBm. From the simulation results, we observe that BER decreases with decrease in average length of PPM symbol L under different turbulence conditions in FSO Communication system.
关键词： FSO Communication System,Subcarrier Intensity Modulation,Atmospheric Turbulence,Bit Error Rate,Average Irradiance
更新于2025-09-12 10:27:22
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Design of Curved Fresnel Lens with High Performance Creating Competitive Price Concentrator Photovoltaic
摘要： In this paper, the design of a curved Fresnel lens applying to the concentrator photovoltaic system is proposed by using the edge ray theorem, the Snell’s law, and the conservation of optical path length. The new structure of the curved Fresnel lens can improve significantly the uniformity of sunlight distribution over the solar cell while the concentration ratio can reach a high value of 900 times. The good uniform distribution can be obtained by using the novel idea. The novel idea is based on the uniform sunlight distribution of every groove of the lens so that the whole lens also distributes uniformly the sunlight beam over the receiver. The structure of the lens is built by two surfaces: input surface (or upper surface) as a part of spherical surface and output surface (or lower surface) that consists all grooves of the lens. Matlab program is used to design the input and the output surfaces of the lens. The input surface and the output surface are independent to each other in construction in Matlab. LighttoolsTM software is used to optimize the structure of the novel lens. Furthermore, LighttoolsTM is also used to perform a simulation to examine the efficiency of the lens in concentrator photovoltaic (CPV) system by using the light source with a wide spectrum of 380 – 1600 nm. The results show that the lens has an acceptance angle of 0.80 and good optical efficiency (>85%).
关键词： concentrator photovoltaic (CPV),Fresnel lens,solar energy,high concentration ratio,multi-junction solar cells,uniform irradiance distribution,CPV without secondary optical element (SOE)
更新于2025-09-12 10:27:22
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[IEEE 2019 International Conference on Smart Energy Systems and Technologies (SEST) - Porto, Portugal (2019.9.9-2019.9.11)] 2019 International Conference on Smart Energy Systems and Technologies (SEST) - Comparative Study of Sky Diffuse Irradiance Models Applied to Photovoltaic Systems
摘要： The increasing energy demand and the search for greener energy resources are expanding interests on photovoltaic systems. These systems need an accurate climatic and irradiation data in order to precisely estimate the energy yield of PV systems. However, most of the available irradiance data, are only for the horizontal plane. The precise estimation of the total irradiance incident on the surface of photovoltaic modules is one of the most important steps in the performance analysis of PV systems. In order to estimate the irradiance on a tilted surface from the irradiance data on the horizontal plane, there are many models available in the literature, they can be classi?ed in isotropic and anisotropic models. This study aims to access the performance of an isotropic and three anisotropic models, which are used by PV system simulation softwares, and the impact of each of them on the estimated energy generation. The results are compared with measured energy data collected at Politec?, Arac?ariguama in Brazil. Results showed that positioning the module at the correct tilted angle and facing north can optimise the global irradiance incident on the module’s surface. Hay & Davies model presented the lowest Mean Bias Error and Root Mean Squared Error while also showing a correlation coef?cient close to 1.
关键词： Sky diffuse models,Solar irradiance,Isotropic model,Anisotropic models,Photovoltaic systems
更新于2025-09-12 10:27:22
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Realtime monitoring on the HIT photovoltaic module characteristic parameters at STC, high and low irradiance conditions in Algeria
摘要： This paper deals with the study on 233 Wp HIT PV module characteristics that defines its performance and operation. The chosen HIT PV module is exposed to outdoor conditions at Saida City of Algeria. The module is tested in high irradiance and low irradiance situations that were recorded over a specific year. Based on the monitored data in these two situations, its performance characteristics were evaluated and compared with standard test condition parameters. From the results it is observed that, irradiance variation effects the HIT PV module characteristics. The variation in maximum power extracted, efficiency, and fill factor were observed. Apart from this weather parameters like ambient temperature, module temperature, wind speed, and relative humidity had also influenced the performance characteristics of HIT PV module.
关键词： fill factor,HIT PV module,PV monitoring,outdoor characteristics,Photovoltaics,PV efficiency,high, low and STC irradiance
更新于2025-09-12 10:27:22
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Improvement of irradiation uniformity by dynamic interference structures of laser array in inertial-confinement-fusion facilities
摘要： In order to improve the irradiation uniformity in inertial confinement fusion facilities, a novel scheme, smoothing by interference structures of laser array, is firstly proposed for improving the irradiation characteristics. In this approach, a pair of identical phase plates with either tilted, cylindrical, elliptical or spiral phase modulates two beamlets, and another pair of phase plates that are conjugate with the former reshapes another two beamlets. Between the beamlets with conjugate wavefront distributions, their central wavelengths are shifted but their polarization states are the same. Arising from the combined effect of the conjugate wavefront distributions and the wavelength differences among the beamlets, the dynamic interference structures are generated in the focal region and thus improve the irradiation uniformity of these beams. Simulation shows that, the superposed focal spot of the beamlets in the focal region is smoothed in transverse, radial or azimuthal direction due to the phase types of the plates, and the required time to achieve the best uniformity is much shorter than the smoothing by spectral dispersion scheme. Moreover, the phase plates can be integrated with the continuous phase plates or be placed in the beamline as pure phase plates in the high-power laser facilities.
关键词： Irradiance uniformity,Beam control,Inertial confinement fusion
更新于2025-09-12 10:27:22
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Optimal Cost of a Solar Photovoltaic System for a Remote House in Bihar
摘要： Energy plays a vital role for the growth of a country. Solar energy is the most important renewable energy resources that can play vital role in the replacement of fossil resources to generate clean energy. Due to technological developments in solar power technologies, solar energy can be used for cooling, heating, and daily electricity demand of the world and emerged as viable alternative to produce clean energy in future. The paper describes the technological development of PV model, its present status and future opportunities in the context of Bihar, India. The study was carried out in Bihar, global solar radiation data is required for the calculation and assessment of the working principles of PV system installed at remotely located house to provide adequate power backup. The case study has been based on the solar radiation data available in Bihar, India, the cost of a suitable PV model for a house has been computed based on the analysis of power requirement of a houses in a day.
关键词： Solar Energy,Solar Radiation,Solar Irradiance,Photovoltaic (PV) system
更新于2025-09-12 10:27:22
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Optimized x-ray sources for x-ray diffraction measurements at the Omega Laser Facility
摘要： The use of x-ray diffraction (XRD) measurements in laser-driven dynamic compression experiments at high-power laser facilities is becoming increasingly common. Diffraction allows one to probe in situ the transformations occurring at the atomic level at extreme conditions of pressure, temperature, and time scale. In these measurements, the x-ray source is generated by irradiation of a solid foil. Under certain laser drive conditions, quasimonochromatic He-α radiation is generated. Careful analysis of the x-ray source plasma spectra reveals that this radiation is not a single line emission and that monochromaticity is highly dependent on the laser irradiance. In this work, we analyze how the spectra emitted by laser-irradiated copper, germanium, and iron foils at the Omega Laser vary depending on different laser drive conditions and discuss the implications for XRD experiments.
关键词： laser irradiance,x-ray diffraction,Omega Laser Facility,quasimonochromatic He-α radiation,laser-driven dynamic compression
更新于2025-09-12 10:27:22