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- 摘要
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- 实验方案
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Wideband Circularly Polarized Antenna Using Single-Arm Coupled Asymmetric Dipoles
摘要： Widespread deployment of large-scale photovoltaics (PVs) and energy storage systems (ESSs) in distribution networks necessitates the development of methods to assess their possible system impacts. One of the primary concerns related to the integration of these systems is short-circuit overcurrent protection problems. Present techniques use simulations of full and detailed distribution circuit models with a large number of scenarios to estimate the PV and ESS sizes a distribution feeder can accommodate without causing adverse impacts. As this process requires considerable time and effort, this paper develops a practical and simplified analytical approach to conservatively estimate a utility distribution feeder’s accommodation limits without causing protection problems. Sympathetic tripping and relay insensitivity problems are considered in this paper under both symmetrical and unsymmetrical fault conditions. Using the analysis presented, the factors influencing these protection problems are determined to provide insights into relay settings. The feeder accommodation limits obtained using the proposed analytical approach are compared with those obtained using simulations of an actual detailed distribution circuit model. The findings show that the proposed approach is accurate in estimating the feeder’s accommodation limits for integrating large-scale PV and ESS.
关键词： Photovoltaic systems,power distribution faults,energy storage systems,short-circuit currents
更新于2025-09-16 10:30:52
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[IEEE 2019 8th International Congress on Advanced Applied Informatics (IIAI-AAI) - Toyama, Japan (2019.7.7-2019.7.11)] 2019 8th International Congress on Advanced Applied Informatics (IIAI-AAI) - Study on Emission of Environmental Load in Photovoltaic Power Generation
摘要： Widespread deployment of large-scale photovoltaics (PVs) and energy storage systems (ESSs) in distribution networks necessitates the development of methods to assess their possible system impacts. One of the primary concerns related to the integration of these systems is short-circuit overcurrent protection problems. Present techniques use simulations of full and detailed distribution circuit models with a large number of scenarios to estimate the PV and ESS sizes a distribution feeder can accommodate without causing adverse impacts. As this process requires considerable time and effort, this paper develops a practical and simplified analytical approach to conservatively estimate a utility distribution feeder’s accommodation limits without causing protection problems. Sympathetic tripping and relay insensitivity problems are considered in this paper under both symmetrical and unsymmetrical fault conditions. Using the analysis presented, the factors influencing these protection problems are determined to provide insights into relay settings. The feeder accommodation limits obtained using the proposed analytical approach are compared with those obtained using simulations of an actual detailed distribution circuit model. The findings show that the proposed approach is accurate in estimating the feeder’s accommodation limits for integrating large-scale PV and ESS.
关键词： Photovoltaic systems,power distribution faults,energy storage systems,short-circuit currents
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE PES Innovative Smart Grid Technologies Conference - Latin America (ISGT Latin America) - Gramado, Brazil (2019.9.15-2019.9.18)] 2019 IEEE PES Innovative Smart Grid Technologies Conference - Latin America (ISGT Latin America) - Design of photovoltaic systems on virtual learning platform
摘要： This article presents the development of a virtual learning platform for the design of solar photovoltaic systems. The work carried out involves the inclusion of mathematical models of solar radiation, photovoltaic panels, regulators, batteries and inverters that are integrated to offer a virtual component operation that intervenes in a system for obtaining electrical energy from the solar source. The virtual environment was implemented using the possibilities offered by a graphic programming environment, to facilitate the learning of the design parameters of solar photovoltaic systems.
关键词： Mainel and meinel model,modeling of photovoltaic panels,Design of photovoltaic systems
更新于2025-09-16 10:30:52
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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) - Modular Architecture with Power Optimizers for Photovoltaic Systems
摘要： Solutions that increase ef?ciency in renewable energy are important for environmental sustainability. In this way, dealing with photovoltaic generation a new architecture constituted by power optimizer for photovoltaic systems emerges. Power optimizer is a DC/DC converter, allocated to each one or two photovoltaic modules, that tries to reduce losses in photovoltaic systems, increasing the photovoltaic power generation. Thus, this paper presents the architecture used in a photovoltaic system with power optimizer and a performance simulation for application in a residence and a photovoltaic plant. Thus, it is possible to measure the gain provided by power optimizer in simulated systems. As a result, the application of the photovoltaic system in residence provided better performance than the application in the photovoltaic plant, due to the greater frequency of shading in the photovoltaic modules. Therefore, power optimizer for photovoltaic systems is a solution that can be considered, mainly with the reduction of the cost of power electronics in the future.
关键词： power optimizer for photovoltaic systems,architecture,photovoltaic,Renewable energy,Modular Architecture
更新于2025-09-16 10:30:52
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Implementation of a modified circuit reconfiguration strategy in high concentration photovoltaic modules under partial shading conditions
摘要： A modified circuit reconfiguration (MCR) technique for high concentration photovoltaic (HCPV) modules under partial shading conditions (PSCs) is proposed. Although HCPV modules have high conversion efficiency, they are sensitive to changing environments, especially PSCs. In response, the MCR strategy exploits the reconfigurable wiring of HCPV modules to implement the dynamic circuit reconfiguration (DCR) technique. In doing so, the hardware switches and complex control algorithms of the conventional DCR are simplified to reduce cost. Moreover, an irradiation estimation method is proposed for string current equalization using existing switches and connections. Two circuit-model prototypes, one square and one rectangular, were simulated to evaluate the proposed MCR strategy. Evaluation results demonstrate that the average output-power and conversion-efficiency improvements of the square and rectangular modules were around 31.07% and 5.00%, and 32.79% and 5.23%, respectively, when compared with the original Series connection topology. In addition, after reconfiguration by MCR, the module’s GMPP power was improved and the number of LMPPs reduced, which simplified the P-V curves. Furthermore, reliability tests demonstrated that with a small reconfiguration processing time ratio (0.06–0.28%), the daily energy harvested from the rectangular module was improved around 15%. The proposed MCR strategy has the advantages of reducing the hardware/software costs and lowering circuit losses. Additionally, the MCR method can increase the output power and efficiency of an HCPV module with high dispersion ability. The proposed method and prototypes can also be extended to larger scale arrays or implemented with other PV systems.
关键词： High concentration photovoltaic systems (HCPV),Maximum power point tracking (MPPT),Dynamic circuit reconfiguration,Partial shading conditions (PSCs)
更新于2025-09-16 10:30:52
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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) - Photovoltaic Module Parametric Identification
摘要： Photovoltaic (PV) modules electrical behavior is described by using the Single Diode Model (SDM), which gives a good tradeoff between accuracy and complexity. This model gives a relation between the PV current and the PV voltage that is non linear and also implicit. Nevertheless, in literature it is shown that a useful expression of the PV current iPV as an explicit function of the PV voltage vPV is available by using the Lambert W-function. The five parameters {Iph, Is, η, Rs, Rsh}, that appear in the equations, are the photo induced current, the saturation current, the ideality factor, the series and the shunt resistances, respectively. The values of the five parameters are usually determined in Standard Test Conditions (STC) on the basis of PV module operating data taken from the data sheet. Many approaches to the PV SDM parametric identification in STC have been published in literature. Some of them use a number of points describing the current vs. voltage (I-V) curve, thus their input is not limited to the data available in the data sheet. Other authors investigate the use of an optimization algorithm for determining the set of the five parameters that minimizes the difference between the model and the current/voltage measured couples available. Usually the function to be minimized is the Root Mean Square Error (RMSE). The equation and the SDM parameters and the experimental data are often used for bounding the search space or to fix a suitable guess solution in order to improve the convergence rate of the algorithm and reduce its computational effort. Such approaches are more oriented to an off-line identification, because of the difficulty of running an optimization algorithm through an embedded system, with limited memory and processing resources. Instead, for the on-site applications, the approaches presented seem to be more suitable, because they use straightforward formulae relating experimental data to SDM parameters values, so that a limited computational effort is required. The price to pay is the higher RMSE, with respect to approaches based on the use of an optimization algorithm, which keeps limited to a reasonable value for the on-site uses. Unfortunately, in normal outdoor operation, parametric identification becomes more tricky, because the irradiance and temperature data are not always available. Indeed, the on-field measurement of irradiance and temperature is expensive and often impractical, especially when the PV array includes many modules. Nevertheless, the parametric identification of the PV module or string in outdoor conditions is very useful for diagnostic purposes. Thus, numerical approaches that can be even implemented by using cheap embedded systems are very interesting for on-field implementation. In this paper a possible approach to the on-field identification of the working parameters of a PV module is presented. The approach takes as input the I-V curve of the PV module acquired in a number of voltage samples. The identification results are related to I-V curves that are experimentally acquired at the PV plant of the Tampere University in Finland. Experimental measurements are analyzed by applying novel results and methodologies presented in the recent literature. Application of the proposed method to identify the increase of the series resistance Rs appearing in the SDM of the PV module is also envisaged.
关键词： diagnosis,parametric,photovoltaic systems,identification
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE PES Innovative Smart Grid Technologies Conference - Latin America (ISGT Latin America) - Gramado, Brazil (2019.9.15-2019.9.18)] 2019 IEEE PES Innovative Smart Grid Technologies Conference - Latin America (ISGT Latin America) - Method to trace the photovoltaic characteristic curves under partial shading conditions
摘要： The I-V curve is an important parameter, because it has the characteristics of PV panel. It shows compactly that happens in the module due external variations. In this article presents a method to trace the photovoltaic curves under partial shading conditions. Also, it mentions the effects of the bypass diode. Lastly, it makes comparisons between curves of shaded panels and panels with regular irradiance.
关键词： Photovoltaic systems,Lambert function,Newton-Raphson,PV partial shading
更新于2025-09-16 10:30:52
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Aerial Infrared Thermography: A Scalable Procedure for Photovoltaics Inspections Based on Efficiency and Flexibility
摘要： The objective of this contribution is to explore innovative ways to increase the efficiency of large scale photovoltaic systems (LSPVS) in the medium term through effective management of operating, monitoring and maintenance (OMM) costs based on aerial surveillance with small multi-rotor flight robot (s-MRFR). An effective solution of OMM cost assessment must capture the dynamic interaction between energy market developments, technological progress and investor tolerance to the risk posed by climate changes. The valuation method for OMM cost-risk analysis is based on generalized Wiener process with stochastic jumps. The interest is to increase the value of the investment by using innovative but efficient procedures of PV systems inspection based on aerial infrared thermography. The results are encouraging because the total costs of s-MRFR monitoring are very low compared to the benefits.
关键词： Photovoltaic systems,small multi-rotor flight robot,aerial infrared thermography,climate change impacts,cost analysis
更新于2025-09-16 10:30:52
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A novel Lyapunov stable higher order B-spline online adaptive control paradigm of photovoltaic systems
摘要： In this paper, research on the control of photovoltaic (PV) using a novel higher order B-spline online adaptive neuro-fuzzy paradigm considering high external uncertainties in weather and load demand is presented. We optimize the existing neuro-fuzzy technique by incorporating third order B-spline membership functions in its antecedent part, which we solve using an on-line learning gradient-decent back propagation method. We fit the system parameters online through adaptive fuzzy rules extracted from the maximum power point tracking (MPPT) error and its derivative. Unlike many existing neuro-fuzzy techniques, our method addresses the trapping in local minima. The proposed controller is demonstrated to be stable using Lyapunov stability analysis. The performance of our control philosophy is checked in terms of output power tracking, efficiency, and MPPT error. Finally, we validate via simulation the high robustness and the self-adaptation ability of the proposed method over other existing traditional and intelligent techniques.
关键词： B-spline membership functions,Photovoltaic systems,Maximum power point tracking,Adaptive neuro-fuzzy control,Lyapunov stability
更新于2025-09-16 10:30:52
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Assessment of Existing Photovoltaic System with Cooling and Cleaning System: Case Study at Al-Khobar City
摘要： There is no denial that renewable energy is considered to be the most cost-competitive source of clean power in many parts of the world. Saudi Arabia’s vision 2030 aims at achieving the best by using di?erent sources of renewable energy such as solar energy, wind energy, and others. The use of solar energy in particular for power generation will decrease the dependency on oil, and thus, decrease the greenhouse gasses. Solar panels e?ciency tends to decrease with the accumulation of dust on their surface. Thus, a cleaning process requires assigning and employing labor, which increases the cost of running as well as high cost of machinery. The current study focuses on assessing and designing a simple auto self-cleaning system in order to improve the e?ciency of the solar panel. The results showed that for the Al-Khobar region, Eastern Province, Kingdom of Saudi Arabia, the e?ciency of the solar panels after cleaning was increased from 6% to an average of 12% at nominal temperature of 27 C. In addition, the average power output was increased by 35% during the day time. In addition, the normal e?ciency of the solar panels before cooling was between 10% to 15% at 42 C and the e?ciency increased by 7%. Moreover, the output power was increased by 31% with maximum e?ciency of 32% at noon time. After cooling, the temperature of solar cells decreased to 20 C.
关键词： cooling,real case study,e?ciency,photovoltaic systems,renewable energy,cleaning
更新于2025-09-16 10:30:52