Magnetization Dynamics Modeling in a Like Iron-Silicon Thin Film by the Micromagnetic Approach
Journal of Magnetics, Sep 29, 2023
Distribution Grid Protection
2019 Algerian Large Electrical Network Conference (CAGRE)
the protection devices constantly monitor the electrical state of the elements of a network and c... more the protection devices constantly monitor the electrical state of the elements of a network and cause them to be de-energized (for example the opening of a circuit-breaker), when these elements are the seat of an undesirable disturbance: short-circuit, lack of insulation, surge, etc. The choice of a protective device is not the result of isolated reflection, but one of the most important steps in the design of an electrical network.From the analysis of the behavior of the electrical equipment’s (motors, transformers, cables, etc.) On defects and the phenomena which result from it, one chooses the most adapted protection devices that are what one goes present in this article.
Neural networks and fuzzy logic approaches to predict mechanical properties of XLPE insulation cables under thermal aging
Neural Computing and Applications, 2016
The widespread use of cross-linked polyethylene (XLPE) as insulation in the manufacturing of medi... more The widespread use of cross-linked polyethylene (XLPE) as insulation in the manufacturing of medium- and high-voltage cables may be attributed to its outstanding mechanical and electrical properties. However, it is well known that degradation under service conditions is the major problem in the use of XLPE as cable insulation. Laboratory investigations of the insulations aging are time-consuming and cost-effective. To avoid such costs, we have developed two models which are based on artificial neural networks (ANNs) and fuzzy logic (FL) to predict the insulation properties under thermal aging. The proposed ANN is a supervised one based on radial basis function Gaussian and trained by random optimization method algorithm. The FL model is based on the use of fuzzy inference system. Both models are used to predict the mechanical properties of thermally aged XLPE. The obtained results are evaluated and compared to the experimental data in depth by using many statistical parameters. It is concluded that both models give practically the same prediction quality. In particular, they have ability to reproduce the nonlinear behavior of the insulation properties under thermal aging within acceptable error. Furthermore, our ANN and FL models can be used in the generalization phase where the prediction of the future state (not reached experimentally) of the insulation is made possible. Additionally, costs and time could be reduced.
汚染された絶縁体‐動的モデリングの新しい高電圧直流フラッシュオーバ【Powered by NICT】
IEEE Conference Proceedings, 2016
New HVDC flashover of polluted insulators -dynamic modeling
2016 IEEE International Conference on High Voltage Engineering and Application (ICHVE), 2016
This study presents the improved flashover dynamic model based on both, impedance criterion for t... more This study presents the improved flashover dynamic model based on both, impedance criterion for the discharge propagation and energy balance criterion for estimating the discharge displacement. One main contribution in this paper is that our model it's enabling to predict the instantaneous changes of the discharge characteristic such as leakage current, discharge temperature, arc resistance and also the temporal evolution of their analytics parameters (A, N). To demonstrate the efficiency of the developed model we applied it for flat plat insulators model which are polluted only with NaCl. Taking advantage of the designed model, we originate to take into account the majority of physical and thermal discharge properties such as analytics parameters (we elsewhere presented) and a particular solution of Elenbaas-Heller equation that has been proposed by Frank-Kamenetski and the temperature parameter. Of particular interest, the previous parameter (i.e., temperature) which is the most preponderant factor in our model has not been treated above in the literature for dynamic model. Finally, the obtained computer simulations are in good agreement with the experimental results.
Study by simulation of the electric field within dielectric environments
Proceedings of the 2004 IEEE International Conference on Solid Dielectrics, 2004. ICSD 2004.
ABSTRACT Our work consists to develop a computer code based on charge simulation method and to ap... more ABSTRACT Our work consists to develop a computer code based on charge simulation method and to apply it for the calculation of the electrostatic field in important and complex geometries containing several homogeneous mediums. In particular calculation of the field with axial symmetry, the analytical example is a geometry stem plan, the plan representing a heterogeneous ground of variable conductivity.
Simulation d’une Décharge Electrique Multi-Branches, sur une Surface Isolante Polluée Modélisant un Isolateur HT
Numerical Modeling a Conductor Metal Enclosure Covered With a Dielectric Layer Illuminated By an Electromagnetic Wave
Modeling of DC-DC converters based on Fibonacci-Horner theorem
3rd International Conference on Systems and Control, 2013
ABSTRACT This paper deals with DC-DC converters modeling and behavior description. Our main purpo... more ABSTRACT This paper deals with DC-DC converters modeling and behavior description. Our main purpose is to describe accurately the DC-DC converters behavior based on Fibonacci-Horner decomposition theorem. The proposed model has the same performances as the detailed model with less computing time/data size and without neither simplifying hypothesis nor validity conditions. The obtained model is validated through simulation using Buck and Boost converters and by the mean of comparative study between the proposed modeling approach and those proposed in literature based on Cayley-Hamilton and spectral decomposition theorems.
A. Hamzaoui, Nonlinear phenomena control in DC-DC converters using dynamical ramp
HAL (Le Centre pour la Communication Scientifique Directe), 2010
Simulation and Experimental Investigation of Nonlinear Phenomena in Boost Converter
HAL (Le Centre pour la Communication Scientifique Directe), 2013
Determination of are re-ignition conditions on polluted insulating surfaces
The paper comprises an experimental investigation into the influence of AC conditions, in order t... more The paper comprises an experimental investigation into the influence of AC conditions, in order to maintain an arc burning on a dielectric surface. The present work proposes a regression model which is based on re-ignition conditions as an important factor in determining the flashover criterion of a polluted insulator under AC voltage. The measuring method and results of the re-ignition
International Journal of Power Electronics and Drive Systems, Sep 1, 2015
This paper presents the practical analysis of Boost converter operating in continuous conduction ... more This paper presents the practical analysis of Boost converter operating in continuous conduction mode under current control. We start by theconverter modeling, then experimental results will be exposed where we propose an experimental circuit, to study the influence of the variation of different circuit parameters such as reference current, input voltage and load. We also analyze the control technique performances. The experimental results are given and interpreted in each case.
Combined effects of electrostatic and electromagnetic interferences of high voltage overhead power lines on aerial metallic pipeline
Facta universitatis - series: Electronics and Energetics
The main purpose of this paper is to model and analyze the electrostatic and electromagnetic inte... more The main purpose of this paper is to model and analyze the electrostatic and electromagnetic interferences between a HV overhead power line and an aerial metallic pipeline situated parallel at a close distance. The modelling of these interferences is typically done for safety reasons, to ensure that the induced voltage does not pose any risk to the operating and maintenance personnel and to the integrity of the pipeline. The adopted methodologies respectively for electrostatic and electromagnetic interferences are based on the charge and current simulation methods combined with the Teaching learning based optimization (TLBO) algorithm. The Friedman test analysis indicate that teaching learning based optimization (TLBO) algorithm can be used for parameters optimization, it showed better results. In the case where the induced currents and voltages values exceed the limit authorized values by the international CIGRE standard, mitigation measures become necessary. The simulation results...
The effect of temperature and the mutual influence between two cavities of on the appearance of partial discharges in gaseous cavities contained in the insulator of high voltage
2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena
ABSTRACT Our work treat the effect of the temperature on the appearance of partial discharges in ... more ABSTRACT Our work treat the effect of the temperature on the appearance of partial discharges in high voltage cables. We modelize the heterogeneous insulator of the cable using finite difference method. The numerical treatment is carried out in bidimensional due to the observed symmetry in the cavities. We simulate regions of weak concentration to an insulator containing one cavity, this is justified by the absence of interactions between cavities. The regions of great concentrations are simulated to an insulator, which contain two cavities in mutual interactions. Once the two cavities are in contact, we speak then of a complex defect called "bi-vacuole". The physical proprieties two simulate are the electrical field and the temperature. We present the results of computation obtained by an established program, this result show that the partial discharge is occurred in cavities of small diameters in regions either near the core or the wrapping. The mutual interaction between cavities contributes much the apparition of the partial discharges.
Optical analysis of an electric discharge evolution on an insulating polluted surface materializing a polluted insulator
2009 International Conference on Electrical and Electronics Engineering - ELECO 2009, 2009
We observed the extension of a discharge on an electrolyte surface either with an electronic came... more We observed the extension of a discharge on an electrolyte surface either with an electronic camera or by using an original set-up permitting simultaneous measurements of optical and electrical parameters on the same flashover. The corresponding results are presented here. They show two zones of different luminosity, the development of which are very different. Zone 1, the darker of the two, is nearer the ground electrode, whereas the zone 2, the brighter one, is behind it starting from the HV electrode and has a better defined outline. At the onset of the flashover in its first phase, the zone 1 spreads faster than the zone 2. Later, in a shorter second phase, the zone 2 develops more quickly and progressively overruns the zone 1. Thereafter, suddenly the flashover is completed. We comment these results and suggest an explanation.
Contournement �lectrique sous tension alternative d�un canal rempli d��lectrolyte
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