Search results for "Volt"
showing 10 items of 2187 documents
A Deep Learning Approach for Automated Fault Detection on Solar Modules Using Image Composites
2021
Aerial inspection of solar modules is becoming increasingly popular in automatizing operations and maintenance in large-scale photovoltaic power plants. Current practices are typically time-consuming as they make use of manual acquisitions and analysis of thousands of images to scan for faults and anomalies in the modules. In this paper, we explore and evaluate the use of computer vision and deep learning methods for automating the analysis of fault detection and classification in large scale photovoltaic module installations. We use convolutional neural networks to analyze thermal and visible color images acquired by cameras mounted on unmanned aerial vehicles. We generate composite images…
Comparative Analysis of Different Types of Micro-grid Architectures and Controls
2018
An innovative and smart micro-grid model is an essentialfor the integration of distributed energy resources into the electrical power distribution network. There are various types of micro-grid architectures that have been designed and implemented in the last few years. These micro-grid architectures have their key advantages and limitations. This paper has been prepared with the objective to identify and address, key challenges and solutions for integration of micro-grid into the distribution network. It reviewsdifferent micro-grid architectures and control strategies which can help to address various challenges i.e. voltage imbalance, power quality, demand side management, smooth islandin…
Evaluation of an Optical Energy Harvester for SHM Application
2019
Abstract In this paper a preliminary study on an array configuration of rectified optical nanoantennas for energy harvesting application is proposed. Currently, the major impediments for the use of the rectified optical nanoantenna known as rectenna are the relatively low conversion efficiency and low power transfer to the load, both of them caused mainly by the mismatch between the impedance of the rectifier (several kilo ohms) and that of the antenna (hundreds of ohm). For this reason, the design of the array represents a crucial point to obtain the maximum energy transfer from the rectenna to the load, represented as a typical DC/DC boost power converter, and modeled by an equivalent inp…
Autonomous Demand Side Management of Electric Vehicles in a Distribution Grid
2019
The electricity demand due to the increasing number of EVs presents new challenges for the operation of the electricity network, especially for the distribution grids. The existing grid infrastructure may not be sufficient to meet the new demands imposed by the integration of EVs. Thus, EV charging may possibly lead to reliability and stability issues, especially during the peak demand periods. Demand side management (DSM) is a potential and promising approach for mitigation of the resulting impacts. In this work, we developed an autonomous DSM strategy for optimal charging of EVs to minimize the charging cost and we conducted a simulation study to evaluate the impacts to the grid operation…
Drift Modeling of Electrically Controlled Nanoscale Metal–Oxide Gas Sensors
2008
Gas sensors with small dimensions offer the advantage of electrical sensitivity modulation. However, their actual use is hindered by drift effects that exceed those of usual metal-oxide sensors. We analyzed possible causes and found the best agreement of experimental data with the model of internal dopant fluctuations. The dopants are oxygen vacancies exhibiting high drift-diffusion coefficients under the impact of electrical fields. Thus, the width parameters of space charge regions, which again control the sensor current, are undergoing slow changes. Moreover, the dopant distributions cause internal electrical fields that yield drift even after voltage switch-off. This behavior has been p…
Effects of water dielectric saturation on the space–charge junction of a fixed-charge bipolar membrane
2000
Abstract The dielectric saturation at the space–charge junction of a fixed-charge bipolar membrane is studied using the theoretical approach by Booth for the water dielectric constant and the Poisson equation for the electrical double layer at the junction. The numerical solution gives the electric field and dielectric constant profiles through the junction as well as the junction thickness as a function of the voltage drop. The water dielectric constant decreases substantially for the large electric fields that may occur at the narrow bipolar junction.
Evaluation of the electrochemical anion recognition ofNO3−-imprinted poly(Azure A) inNO3−/Cl−mixed solutions by ac-electrogravimetry
2016
Abstract During the reversible electrochemical reactions of the intrinsically conducting polymer (ICP) films, ions are inserted in them to balance the inner charge site of the polymer. For this reason, doped ICP films with anions or cations can be good candidates for the electrochemical removal of contaminant ions from wastewater. In this work, a polymer of a phenothiazine derivative (poly(Azure A or PAA)) was electrosynthesized by cyclic voltammetry in aqueous solutions using nitrate ions as a structural template. After that, PAA film was repeatedly cycled in identical conditions in a monomer-free solution. The electrochemical anion recognition of the nitrate-imprinted poly(Azure A) ( N O …
Charging process in electron conducting polymers: dimerization model
2001
Abstract Theory of the charging and discharging process in electron-conducting polymer films at an electrode surface has been presented. It is based on the concept of two coexisting subsystems at the polymer matrix, ‘usual’ sites P which can exchange with the electrode by the electronic charge in a quasi-reversible manner, and sites D where intermolecular bonds between neighboring polymer molecules can be formed. The charging and discharging of the latter subsystem may be realized along different reaction pathways, e.g. via the bond formation after the generation of two cation radicals within such site D in the course of the anodic scan while the bond dissociation may take place via a parti…
Electrically conductive hydrogel composites made of polyaniline nanoparticles and poly(N-vinyl-2-pyrrolidone)
2006
Abstract A novel electrically conductive composite material, consisting of polyaniline (PANI) nanoparticles dispersed in a polyvinyl pyrrolidone (PVP) hydrogel, was prepared ‘in situ’ by water dispersion polymerisation (DP) of aniline using PVP as steric stabiliser, followed by γ-irradiation induced crosslinking of the PVP component. Conversion yield of aniline into PANI particles was determined via HPLC and gas chromatography, while structural confirmation of the synthesised polymer was sought by FTIR. Morphology and dimensions of PANI particles into the coloured, optically transparent hydrogel was determined by electronic microscopy; moreover, swelling behaviour of composite hydrogels in …
Third-Generation Solar Cells: Concept, Materials and Performance - An Overview
2019
The large scarcity of natural fuels in earth crust has triggered to search alternative energy reservoirs for the future generation of human life. Because of large abundancy, solar energy is considered as big hope for the future generation energy utilization for commercial as well as home applications. The scientific revolution achieved in synthesis and processing of semiconductor nanomaterials, organic conducting polymers have led into new dimension in fabrication of future-generation solar cells. Reduction in the dimension of semiconductor nanomaterials significantly influences on their structural and optical properties which is helpful for the excellent photon harvesting. Also, their larg…