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- 摘要
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Multivariate feature extraction based supervised machine learning for fault detection and diagnosis in photovoltaic systems
摘要: Fault detection and diagnosis (FDD) in the photovoltaic (PV) array has become a challenge due to the magnitudes of the faults, the presence of maximum power point trackers, non-linear PV characteristics, and the dependence on isolation efficiency. Thus, the aim of this paper is to develop an improved FDD technique of PV systems faults. The common FDD technique generally has two main steps: feature extraction and selection, and fault classification. Multivariate feature extraction and selection is very important for multivariate statistical systems monitoring. It can reduce the dimension of modeling data and improve the monitoring accuracy. Therefore, in the proposed FDD approach, the principal component analysis (PCA) technique is used for extracting and selecting the most relevant multivariate features and the supervised machine learning (SML) classifiers are applied for faults diagnosis. The FDD performance is established via different metrics using data extracted from different operating conditions of the grid-connected photovoltaic (GCPV) system. The obtained results confirm the feasibility and effectiveness of the proposed approaches for fault detection and diagnosis.
关键词: fault classification,fault diagnosis,photovoltaic (PV) systems,feature extraction,Supervised machine learning (SML),principal component analysis (PCA)
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 3rd Advanced Information Management, Communicates, Electronic and Automation Control Conference (IMCEC) - Chongqing, China (2019.10.11-2019.10.13)] 2019 IEEE 3rd Advanced Information Management, Communicates, Electronic and Automation Control Conference (IMCEC) - Capacity Configuration Method of Hybrid Energy Storage System for Stand-Alone Photovoltaic Generation System
摘要: To enhance photovoltaic (PV) utilization of stand-alone PV generation system, a hybrid energy storage system (HESS) capacity configuration method with unit energy storage capacity cost (UC)and capacity redundancy ratio (CRR) as the evaluation indexes is proposed, which is considering different types of load. First, the HESS power difference between the load demand power and the PV output power is obtained by the method, which is allocated by the low-pass filtering algorithm. According to the characteristics of power type and energy type energy storage device, the low frequency component is borne by the energy-type energy storage device, and the high-frequency component is borne by the power-type energy storage device, taking HESS charging and discharging efficiency,SOC upper and lower limits and capacity attenuation as the constraints. Then, based on the whole life cycle cost, analyzing the different effects of different PV power generation energy and load types on the indexes. Finally, the feasibility and effectiveness of this method are analyzed by 3 actual examples.
关键词: capacity configuration,hybrid energy storage system (HESS),Stand-Alone photovoltaic (PV) System,whole-life-cycle cost
更新于2025-09-19 17:13:59
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Copper-Plating Metallization With Alternative Seed Layers for c-Si Solar Cells Embedding Carrier-Selective Passivating Contacts
摘要: In this article, we develop in parallel two fabrication methods for copper (Cu) electroplated contacts suitable for either silicon nitride or transparent conductive oxide antire?ective coatings. We employ alternative seed layers, such as evaporated Ag or Ti, and optimize the Ti–Cu or Ag–Cu contacts with respect to uniformity of plating and aspect ratio of the ?nal plated grid. Moreover, we test plating/deplating sequence instead of a direct current plating or the SiO2 layer approach to solve undesired plating outside the designed contact openings. The main objective of this paper is to explore the physical limit of this contact formation technology keeping the process compatible with industrial needs. In addition, we employ the optimized Cu-plating contacts in three different front/back-contacted crystalline silicon solar cells archi- tectures: 1) silicon heterojunction solar cell with hydrogenated nanocrystalline silicon oxide as doped layers, 2) thin SiO2/doped poly-Si-poly-Si solar cell, and 3) hybrid solar cell endowed with rear thin SiO2/poly-Si contact and front heterojunction contact. To investigate the metallization quality, we compare fabricated devices to reference ones obtained with standard front metallization (Ag screen printing and Al evaporation). We observe a relatively small drop in VOC by 5 to 10 mV by using Cu-plating front grid, whereas ?ll factor was improved for solar cells with Cu-plated front contact if compared with evaporated Al.
关键词: Photovoltaic (PV),Si PV device fabrication,photovoltaic cells,PV process control
更新于2025-09-16 10:30:52
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[IEEE 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA) - Xi'an, China (2019.6.19-2019.6.21)] 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA) - Analysis and Design of a Novel Transformer-less-Inverter in Grid-Connected Photovoltaic System
摘要: The continuous urge for improvement in our standard of living has increased the consumption of electrical energy by leaps and bounds. This hike in energy consumption, draining of fossil fuels and degrading global environment has led to invention of green power generation systems. Thus, the global demand for renewable resources has led to flourishing of photovoltaic (PV) market. The enabling technology in the PV systems is the inverter, which could be either: 1) with transformer isolated or 2) without transformer non-isolated (transformer-less inverter). Recently, single phase transformer- less voltage source inverters (VSI) have been extensively used for distributed photovoltaic grid tied systems. The objective of this paper is to review a few notable topologies and propose a new topology for transformer-less photovoltaic inverter. The analysis and design of the proposed topology is verified by simulating it on PSIM. Furthermore, the simulation results are validated by testing a proof-of-concept laboratory hardware prototype rated at 250 W.
关键词: Photovoltaic (PV) systems,transformer-less,single phase inverter
更新于2025-09-16 10:30:52
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Power recovery and equalization in partially shaded photovoltaic strings by an efficient switched capacitor converter
摘要: Partial shading is the major complication encountered by the Photovoltaic strings while delivering maximum power to the load. This scenario consequently diminishes the functionality of the modules causing mismatch, hotspot, power loss and multiple peaks formation in the characteristics curves of the strings. Also, formation of multiple peaks affects the performance of the maximum power point trackers due to false tracking resulting in severe power loss. In this paper, a switched-capacitor converter for power recovery and equalization in the strings during shading is proposed. The parallel-ladder architecture of the converter maintains voltage ratios by transferring power between the shaded and unshaded modules of the strings. The converter enables the string to generate maximum power by ensuring single peak in the characteristics curves during shading. The performance of the string with the proposed converter is compared to conventional strings using characteristics curves, and various performance parameters. The systems are tested in MATLAB/Simulink and experimental setup under various static and dynamic partial shading conditions. Also, the conduction losses encountered by the converter during power balancing in the strings are analysed and expressed mathematically. The results clearly indicate that the proposed converter can be easily implemented in the strings to recover the power losses and avoid multiple peaks formation in the characteristics curves during partial shading with efficiency greater than 99%.
关键词: Maximum power point,Photovoltaic (PV) strings,Partial shading,Differential power processing (DPP),Switched-capacitor (SC) converter
更新于2025-09-16 10:30:52
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Performance Analysis of Submerged Polycrystalline Photovoltaic Cell in Varying Water Conditions
摘要: Exploring the underwater solar energy by solar photovoltaic (PV) cells leads to a huge advantage by utilizing the humongous space of water covered by the earth’s surface. Even though the amount of solar radiation decreases with the depth of the water, water provides sustainable cooling and cleaning for solar PV cells underwater. There are many challenges and constraints to develop solar PV cells underwater because they are mostly calibrated and amenable to space, dryland, terrestrial, etc., and the solar spectrum is prone to get narrower with the depth of the water. The implementation of solar PV cells underwater is pliable in various commercial and defense applications, such as sensors, water monitoring systems, autonomous vehicles, underwater gliders, etc. In this article, first, a mathematical model has been developed for the solar cell spectrum to incorporate the changes in the solar irradiance with the depth of the water. Furthermore, an experimental setup was designed and implemented to mimic an underwater environment. The performance of the polycrystalline encapsulated solar cell was studied based on the different types of water and the depth of the solar cell underwater. This article manifests that there is a sufficient amount of underwater solar power that can be utilized using PV cells to operate various devices and systems.
关键词: polydimethylsiloxane (PDMS),Photovoltaic (PV) cells,underwater solar power,polycrystalline solar cell,solar spectrum,water salinity,solar irradiance
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Chengdu, China (2019.5.21-2019.5.24)] 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Review on modeling of photovoltaic power generation systems
摘要: In recent years, photovoltaic (PV) power generation has developed rapidly at China and abroad. PV power generation is on the trend from auxiliary power supply to main power supply even leading power supply. Due to the fluctuation and intermittent characteristics of PV power generation, and zero inertia, the integration of large-scale grid-connected PV power generation may have a negative impact on the stability of the power system. Modeling grid-connected PV power generation systems is the key factor to investigate the influence between it and other parts of power system. Modeling of PV is also a hot issue that has been studied continuously for many years around the world. GE, WECC, CIGRE, CEPRI and so on have attached great importance to this issue and have published many research results. The existing research at China and abroad is reviewed in this paper, the existing problems are analyzed, and suggestions for future research are given.
关键词: power plant,model validation,photovoltaic (PV) power generation,power unit,modeling
更新于2025-09-16 10:30:52
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Simulation-Based Exergy Analysis of Large Circular Economy Systems: Zinc Production Coupled to CdTe Photovoltaic Module Life Cycle
摘要: The second law of thermodynamics (2LT) helps to quantify the limits as well as the resource efficiency of the circular economy (CE) in the transformation of resources, which include materials, energy, or water, into products and residues, some of which will be irreversibly lost. Furthermore, material and energy losses will also occur, as well as the residues and emissions that are generated have an environmental impact. Identifying the limits of circularity of large-scale CE systems, i.e., flowsheets, is necessary to understand the viability of the CE. With this deeper understanding, the full social, environmental, and economic sustainability can be explored. Exergy dissipation, a measure of resource consumption, material recoveries, and environmental impact indicators together provide a quantitative basis for designing a resource-efficient CE system. Unique and very large simulation models, linking up to 223 detailed modeled unit operations, over 860 flows and 30 elements, and all associated compounds, apply this thermoeconomic (exergy-based) methodology showing (i) the resource efficiency limits, in terms of material losses and exergy dissipation of the CdTe photovoltaic (PV) module CE system (i.e., from ore to metal production, PV module production, and end-of-life recycling of the original metal into the system again) and (ii) the analysis of the zinc processing subsystem of the CdTe PV system, for which the material recovery, resource consumption, and environmental impacts of different processing routes were evaluated, and the most resource-efficient alternative to minimize the residue production during zinc production was selected. This study also quantifies the key role that metallurgy plays in enabling sustainability. Therefore, it highlights the criticality of the metallurgical infrastructure to the CE, above and beyond simply focusing on the criticality of the elements.
关键词: Thermoeconomics,Geometallurgy,Process simulation,Jarosite,Circular economy,Sustainability,Digital twin,Exergy,CdTe photovoltaic (PV) modules
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE PES Innovative Smart Grid Technologies Europe (ISGT-Europe) - Bucharest, Romania (2019.9.29-2019.10.2)] 2019 IEEE PES Innovative Smart Grid Technologies Europe (ISGT-Europe) - Multi-layer Reactive Power Control of Solar Photovoltaic Systems in MV Distribution Network
摘要: The growing penetration of photovoltaic (PV) systems in distribution networks causes various power quality issues e.g. voltage rise, network losses. To deal with the overvoltage, inverter-based reactive power contribution is one of the most commonly proposed approaches. However, using standard strategies with fixed droop parameters limits the control effectiveness. Moreover, much reactive power absorbed by PVs around noon might increase the network loss, overload the substation consequently, especially in the network with long distribution feeders. In this paper, a combined centralized and local control method is proposed with the suggestion of multi-layer structure. Droop parameters of local control are updated every 15 min by centralized control to minimize reactive power flow through substation while keeping voltages in permitted levels. By avoiding overloading substation, more PV generation can be added to the feeder.
关键词: Reactive power control,droop control,particle swarm optimization,voltage control,photovoltaic (PV) systems
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific) - Seogwipo-si, Korea (South) (2019.5.8-2019.5.10)] 2019 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific) - Dynamic Simulation of a Large Power System with High-Capacity Photovoltaic Systems Able to Control Reactive Power
摘要: Relatively small-capacity distributed or clustered photovoltaic (PV) systems change dynamic behaviors of the feeder despite their small capacity. Moreover, modern distributed generation (DG) inverters can control reactive power (i.e., Volt/Var control and management). To connect higher capacity PV systems (i.e., above 50 percent of the total feeder rating) able to control reactive power, various steady-state, transient behaviors, and short-circuit currents affected by the PV systems should be examined in an actual power grid. Thus, the objective of this study is to examine feeder dynamics affected by such a high-capacity PV system able to control reactive power. For this purpose, this study initially models an actual large power grid with thousands of nodes in DIgSILENT, adds high-capacity PV systems (i.e., 50 percent of the feeder rating) with a Volt/Var droop controller to the grid, and generates switching events (i.e.., the circuit breaker on/off) and faults. The Volt/Var control of a high-capacity PV system could mitigate an increase in overvoltage and affect the post-fault voltage because of controlling reactive power. The case study results can be used for the smooth integration of high-capacity DG systems to the grid.
关键词: Volt/Var control,feeder dynamics,DIgSILENT,reactive power control,photovoltaic (PV),fault
更新于2025-09-16 10:30:52