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- IoT based data acquisition system
- Grid tie solar PV system
- IoT
- Losses in Solar PV plant
- Raspberry Pi
- optimum active power
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- photovoltaic system
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- Electrical Engineering and Automation
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Nonlinear Fiber Optics || Optical solitons
摘要： A fascinating manifestation of the fiber nonlinearity occurs through optical solitons, formed as a result of the interplay between the dispersive and nonlinear effects. The word soliton refers to special kinds of wave packets that can propagate undistorted over long distances. Solitons have been discovered in many branches of physics. This chapter focuses on pulse propagation inside optical fibers in the regime in which both the group-velocity dispersion (GVD) and self-phase modulation (SPM) are equally important and must be considered simultaneously. It is organized as follows. Section 5.1 considers the phenomenon of modulation instability and shows that propagation of a continuous-wave (CW) beam inside optical fibers is inherently unstable and may convert the CW beam into pulse train under appropriate conditions. The inverse-scattering method is discussed in Section 5.2 together with the soliton solutions. The properties of the fundamental and higher-order solitons are also discussed in this section. Section 5.3 is devoted to other kinds of solitons, with emphasis on dark solitons. Section 5.4 considers the effects of external perturbations on solitons. Perturbations discussed include fiber losses, amplification of solitons, and noise introduced by optical amplifiers. Higher-order nonlinear effects such as self-steepening and intrapulse Raman scattering are the focus of Sections 5.5 and 5.6.
关键词： modulation instability,optical amplifiers,dark solitons,intrapulse Raman scattering,inverse-scattering method,self-steepening,group-velocity dispersion,fiber nonlinearity,self-phase modulation,fiber losses,optical solitons
更新于2025-09-12 10:27:22
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[IEEE 2019 International Conference on Clean Electrical Power (ICCEP) - Otranto, Italy (2019.7.2-2019.7.4)] 2019 International Conference on Clean Electrical Power (ICCEP) - Comparative Analysis of Partial Shading Power Losses in Photovoltaic Topologies
摘要： The productivity of photovoltaic (PV) system is highly affected by the environmental conditions. The impact of partial shading conditions (PSC) on PV systems with various topologies is not necessarily the same. It is essential to demonstrate the role of PV topology in alleviating partial shading power losses. This paper presents a thorough comparative analysis of power losses incurred under partial shading conditions over different reported PV topologies. Power losses are analyzed for equally-rated PV systems subject to the same environmental conditions to highlight the privilege of some topologies over others. Power losses analysis is carried out based on the level of maximum power point tracking (MPPT).
关键词： partial shading conditions (PSC),power losses,photovoltaic (PV) system,maximum power point tracking (MPPT),PV topologies
更新于2025-09-12 10:27:22
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Small energy loss and high open circuit voltage in conventional structure polymer solar cells with the mixture thin films of polyethylenimine ethoxylated and TiOX as the electron extraction layer and Ag as the cathode
摘要： One of the challenges facing the fabrication of high-performance conventional structure polymer solar cells (PSCs) is the development of new interface materials that have better air stability and charge carrier collection and transport ability. In this study, the mixture thin films of polyethylenimine ethoxylated (PEIE) and TiOX are developed as the electron extraction layer (EEL) and Ag as the cathode for the application in PSCs, replacing the Ca/Al composite cathode. Ultraviolet photoelectron spectroscopy (UPS) and space-charge-limited current (SCLC) measurements demonstrate that PEIE:TiOX/Ag shows appropriate energy levels, substantially reduced barrier potential, weakened charge carrier recombination and enhanced electron mobility. As a result, the PEIE:TiOX-based PSCs demonstrate not only an enhanced power conversion efficiency (PCE) of 10.94% but also the photovoltaic performance insensitive to the storage time, yielding an aged PCE that is 92% of the fresh PCE. This result can be further explained by the dependence of the charge carrier mobility on storage time. Our work suggests exploiting the PEIE:TiOX/Ag composite thin films as the composite cathode replacing Ca/Al thin films for successfully enhancing the photovoltaic performance and improving the stability of PSCs.
关键词： Energy losses,Barrier potential,Charge carrier recombination
更新于2025-09-12 10:27:22
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AIP Conference Proceedings [AIP Publishing 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Fes, Morocco (25–27 March 2019)] 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Characterization of absorption losses in rear side n-type polycrystalline silicon passivating contacts
摘要： Passivating contacts consisting of polycrystalline silicon (poly-Si) and thin silicon-oxide (SiOx) layers facilitate a significant reduction of recombination losses in silicon solar cells. Nevertheless, these gains come with short circuit current density (Jsc) losses due to parasitic absorption by the poly-Si. Even if the passivating contacts are employed at the rear side only, absorption, particularly due to free carriers (FCA) in the heavily doped poly-Si, may still lead to significant Jsc losses. In this work, these losses are characterized as a function of the poly-Si thickness (tpoly) by the analysis of front reflectance spectra in the infrared (IR). For this study, two sets of samples with different n-type full-area poly-Si passivating contacts at the rear are compared to references with a phosphorus(P)-diffused back surface field (BSF) instead. For the two sets, Jsc losses with respect to the references (ΔJsc) are 0.10 mA/cm2 and 0.42 mA/cm2 per 100 nm thick poly-Si, respectively. The difference between the two values is studied by Hall measurements and interpreted to be due to the over three times as high free carrier concentration (ND,act) in the poly-Si layers of the second set of samples as the first set. On the other hand, lifetime measurements showed an excellent passivation yielding an implied open circuit voltage (iVoc) up to 736 mV only for the samples with the more heavily doped poly-Si, whereas iVoc of 683 mV was measured for the first set, which indicates a trade-off between absorption losses and passivation quality.
关键词： infrared reflectance,passivating contacts,solar cells,absorption losses,polycrystalline silicon
更新于2025-09-12 10:27:22
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Perovskite/c-Si Monolithic Tandem Solar Cells Under Real Solar Spectra: Improving Energy Yield by Oblique Incident Optimization
摘要： Many research groups have noticed the performance of rapidly-developed perovskite/silicon monolithic tandem solar cells (TSCs) under real situation, but they overlook the short-current density mismatch of two sub-cells at different times in a day and the spectrum variation at different latitudes. Here we have systematically analyzed the efficiency losses and proposed optimization scheme by combination of experiment and simulation relying on reliable experimental data in a year. We have verified the simulated absorptance spectra varying with incident angle θ to substitute the external quantum efficiency spectra, which makes the optimization at oblique incidence possible. More importantly, we have further calculated and expanded the optimized current losses and energy output enhancement in perovskite/silicon monolithic TSCs to all latitudes. This work can be served as a practical guidance for the design of perovskite/silicon monolithic TSCs with the best annual energy output at different latitudes in the world.
关键词： Perovskite/silicon monolithic tandem solar cells,real solar spectra,efficiency losses,oblique incident optimization,energy yield
更新于2025-09-12 10:27:22
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Visualizing and Suppressing Nonradiative Losses in High Open-Circuit Voltage n-i-p-Type CsPbI <sub/>3</sub> Perovskite Solar Cells
摘要： Since their first demonstration in PV devices in 2009, organic-inorganic hybrid metal halide perovskites have attracted tremendous attention because of their potential applications in solution-processed photovoltaics (PV). Many research efforts, such as composition engineering and interface engineering, have been dedicated to enhancing the power conversion efficiency (PCE) of perovskite-based solar cells (PSCs) to a high level of over 24%. However, operational stability issues remain a major challenge for organic-inorganic hybrid perovskites on the way towards commercialization. Alternatively, all-inorganic perovskites (CsPbX3, X = Cl, Br, I), have received increasing interest because they are theoretically stable up to their melting points (>300 °C). Especially, CsPbI3 in the cubic phase stands out because of the lowest bandgap (of ~1.75 eV) among the all-inorganic lead-based perovskites. Compared to all other all-inorganic lead-based perovskite halide semiconductors materials which have bandgaps higher than 1.90 eV, the 1.75 eV bandgap CsPbI3 is able to absorb slightly more light in the visible region and nominally is an excellent candidate for the front cell in tandem architectures with silicon as the back cell.
关键词： open-circuit voltage,CsPbI3,perovskite solar cells,interface engineering,non-radiative losses,bulk passivation
更新于2025-09-12 10:27:22
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Turning losses into gain in nonlinear optics
摘要： Modulational instabilities in nonlinear optics are the fundamental processes that cause the transition from uniform states to structures in extended systems. Quite counterintuitively, such processes can be enhanced rather than inhibited when spectrally asymmetric losses are introduced into the system.
关键词： gain through losses,modulational instabilities,nonlinear optics,spectrally asymmetric losses
更新于2025-09-11 14:15:04
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Efficient Organic Solar Cells with a High Open‐Circuit Voltage of 1.34 V
摘要： One of the most important challenges that hinders the power conversion efficiencies (PCEs) of organic solar cells (OSCs) is the modest open-circuit voltages (VOC) due to large energy losses. The large driving force during for charge generation and the non-radiative recombination are the main causes of energy losses. To maximize the VOC of OSCs, herein, we modulate the end-groups and design a non-fullerene acceptor ITCCM-O, which shows a bandgap of 2.0 eV. By blending a polymer donor named J52, the device demonstrates a PCE of 5.5% with an outstanding VOC of 1.34 V, which is the highest value for single-junction OSCs over 5% PCEs. The high VOC is benefited from 1) the negligible driving force for charge transfer, and 2) the suppressed non-radiative recombination loss, as low as 0.22 V.
关键词： energy losses,high voltage,non-fullerene acceptors
更新于2025-09-11 14:15:04
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[IEEE 2019 International Conference on System Science and Engineering (ICSSE) - Dong Hoi, Vietnam (2019.7.20-2019.7.21)] 2019 International Conference on System Science and Engineering (ICSSE) - A Method to Estimate the Yield of Photovoltaic Power Plant Solely in MATLAB/Simulink
摘要： The Yield of photovoltaic power plant grid-connected depends upon seasonable variation of solar radiation, system loss, soiling loss, and loss of inverter. This paper presents a method to estimate the yield of photovoltaic power plant solely in MATLAB/Simulink. The yield of photovoltaic power plant grid-connected has been developed based on the photovoltaic model, loss model. In this case, the 1MW solar power plant connected in the grid in three locations in Vietnam have been simulated with the weather season variable and compared with PVGIS software. From the result, the total yield of photovoltaic power plant connected into the grid is range 1180.16 to 1247.42 MWh/Year with the losses system is 28% including losses of system and irradiance losses. Furthermore, the gap between this systems compared with PVGIS software is range -1.47 to 4.64 MWh/Month.
关键词： Yield model,Losses model,Photovoltaic model
更新于2025-09-11 14:15:04
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Study of Power Optimizers for grid-connected photovoltaic systems
摘要： The use of Photovoltaic (PV) energy is increasing and the high penetration of PV in the power grid creates several challenges. The main challenge consists in reducing power losses in conversion. The main losses are those caused by total and partial shading, mismatch losses, ohmic loss, and temperature. In this occasion, Power Optimizer for Photovoltaic Systems (POPS) have recently appeared, which aim at increasing the energy conversion of the PV system. Thus, this work presents the POPS and performs simulations with PV*SOL software verifying the gain provided under different conditions. As a result, in the best case, Optimization Performance (Op) reached 10.84% (SolarEdge) in Sete Lagoas-MG and 7.17% (Tigo) in Curitiba-PR. Therefore, POPS may be a solution for improving energy conversion of the PV system, mainly due to the ongoing reduction in the cost of power electronics.
关键词： POPS,photovoltaic systems,losses,Power optimizer
更新于2025-09-11 14:15:04