Search results for "Electrical & Electronic"
showing 10 items of 489 documents
Supercapacitor diagnosis using an Extended Kalman Filtering approach
2016
This paper deals with the model-based analysis of a Supercapacitor for diagnostic purposes. A two legs nonlinear physical model is assumed for the Supercapacitor and the corresponding second-order nonlinear state-space mathematical model is obtained. Then, an Extended Kalman Filter is tuned so that the estimated outputs reproduce the voltages at the equivalent capacitance terminals; they give information on the state of health of the supercapacitor but are not directly measurable. In particular, an optimization problem is firstly formulated, involving the experimental input-output data and those given by the Extended Kalman Filter.
Power management of a battery/supercapacitor system for E-mobility applications
2019
Hybrid Energy Storage Systems (HESS) have been very popular in recent years in different applications, from electric vehicles (EVs) to smart grids and renewable energies, due to the growing need to accumulate electricity. The concept of hybridization arises from the requirement of both high energy and specific power. The battery/supercapacitor (SC) system offers great advantages in a DC bus, giving the opportunity to provide high amounts of power to the loads. In this paper, a system composed of two bidirectional DC-DC converters, one connected to a battery pack and one to a stack of supercapacitors, is presented for a DC bus in electrical mobility (E-Mobility) applications. The proposed co…
Optimal Integration of Hybrid Supercapacitor and IPT system for a Free Catenary Tramway
2017
The aim of the presented paper is the study of an optimal integration of Supercapacitor based storage system and Inductive Power Transfer system for the free-catenary operation of a tramway. The paper starts from the definition of the Inductive Power transfer pad system and proposed an optimal integration strategy for the correct size of on-board supercapacitors and the inductive energy transfer.
Modelling, Simulation and Characterization of a Supercapacitor in Automotive Applications
2020
The energy storage is one of the most discussed topics among Electrical Vehicles (EVs) research. Currently, supercapacitors (SCs) are collecting even more attention due to their unique features such as high-power density, high life cycle and lack of maintenance. In this paper, a supercapacitor model suitable for the simulation in automotive applications is identified. The model parameters are estimated and used to simulate the behaviour of a commercial SCs bank in different operating conditions. The model is finally validated considering experimental results.
Application of Thermographic Techniques for the Detection of Failures on Photovoltaic Modules
2019
The paper focuses on thermography as a useful investigation tool for diagnosis, detection and prevention of failures of photovoltaic modules. The paper describes the faults detectable by thermographic investigations and how to conduct these investigantions. Then the results of some analyses conducted on a photovoltaic field are presented. The investigations made possible to identify faulty modules with hot spots by measuring localized superheat due to the presence of concentrated deposits on the exposed surface of the module and the superheating due to the presence of sand/dust deposits distributed on a significant portion of the module surface. The thermographic investigations can be used …
Study of the cutting process parameters that influence the surface quality machined by end milling of the aluminum alloy
2019
This research aims to carry out an elaborate experiment by witch resulting in relevant conclusions that have practical applicability in the aeronautical industry. The surface roughness measured transversely and longitudinally on the feed motion direction of the cutting tool constitutes the dedicated objective function on which the study was conducted in this case. The end milling was chosen of an aluminum alloy used explicitly in the aeronautical industry. The actual experiments were carried out in the only aeronautical industry in Romania carrying out these types of machining and were made according to the methodology with rigorous experimental planning of the research. The experimental pl…
Self-management of Information Systems
2016
The paper discusses self-management features that are intended to support the usage and maintenance processes in the information system life. Instead of a universal solutions that are evolved by many researchers in the autonomic computing field, this approach, called smart technologies, anticipates self-management features by including autonomic components into information systems directly. The approach is practically applied in several information systems, and the gained results show that the implementation of self-management features requires relatively modest resources. Thereby the approach is suitable even for smaller projects and companies.
Day-to-Day Variability and Year-to-Year Reproducibility of Accelerometer-Measured Free-Living Sit-to-Stand Transitions Volume and Intensity among Com…
2021
(1) Background: The purpose of this study was to evaluate the day-to-day variability and year-to-year reproducibility of an accelerometer-based algorithm for sit-to-stand (STS) transitions in a free-living environment among community-dwelling older adults. (2) Methods: Free-living thigh-worn accelerometry was recorded for three to seven days in 86 (women n = 55) community-dwelling older adults, on two occasions separated by one year, to evaluate the long-term consistency of free-living behavior. (3) Results: Year-to-year intraclass correlation coefficients (ICC) for the number of STS transitions were 0.79 (95% confidence interval, 0.70-0.86, p < 0.001), for mean angular velocity-0.81 (95% c…
Demand Response Service Certification and Customer Baseline Evaluation Using Blockchain Technology
2020
The use of Distributed Ledger Technologies such as Blockchain for certifying Demand Response services allows for the creation of a distributed system in which customers can communicate with the system operator to provide their flexibility, in a secure, transparent and traceable way. Blockchain technology also supports incentive mechanisms for users taking part in the service through the generation of utility tokens to recognize the user's contribution. This paper presents the experimental test of a novel methodology for Demand Response programs implementation by using the Blockchain technology. The latter is employed for defining a distributed Demand Response service and a new system for it…
An original control strategy of storage systems for the frequency stability of autonomous grids with renewable power generation
2021
This work examines the operation of the autonomous power system of a geographical island assuming the integration of significant generation shares from renewable energy sources and the installation of the required storage systems. The frequency stability of the system is investigated considering different operating conditions, in terms of load demand and renewable power generation. The main focus of the work is an original control strategy specifically designed for power converters interfacing storage units to the grid. The proposed strategy is based on an extended frequency droop control, which selects specific droop settings depending on the operating mode—charge or discharge—of the stora…