Now showing items 4-19 of 19

    • Detecting the Liquid core in Continuous Casting Slabs by Load Torque Estimation in Unbending Zone 

      Bivol, Ion; Roşu, Emil; Ceangă, Emil ("Dunarea de Jos" University of Galati, 2002)
      The development in continuous casting process has been strongly dominated by the demands of quality improvement and reduced costs for steel products in recent years. To achieve these goals consideration has been given ...
    • A Diferent Approach in the Parameters' Identification of a Jfet Using Genetic Algorithms 

      Belea, Radu; Beldiman, Liviu ("Dunarea de Jos" University of Galati, 2002)
      The genetic algorithms are developing in three directions: the genetic algorithms theory, the genetic algorithms programming and the study of the problems that can be solved with genetic algorithms. In this paper it is ...
    • Energetic Macroscopic Representation Applied to an Electrical Urban Transport System 

      Popa, Ioan Şerban; Popescu, Mihai Octavian; Popescu, Claudia ("Dunarea de Jos" University of Galati, 2002)
      An energetic description of the electric transport urban system ASTRAIK 415T is proposed according to a specific formalism. This is used to simulate the trolleybus system, equipped with a chopper and a direct current ...
    • Energetic Optimal Control of Adjustable Drive Systems 

      Roşu, Emil; Găiceanu, Marian; Bivol, Ion; Călueanu, Dumitru ("Dunareade Jos" University of Galati, 2002)
      In the paper is developed a new control strategy for the adjustable speed drives. The strategy consists in the energetic optimal control of the dynamic regimes as starting, stopping and reversing. The main developed ...
    • Imperfect Data in Database Context. How are they Stored in Extended Relational Databases? 

      Tudorie, Cornelia ("Dunarea de Jos" University of Galati, 2002)
      Building a more accurate reality model requires taking into account imperfect information present in our knowledge and language. This paper presents several aspects of data imperfection in the database context and the ...
    • Influence of High Performance Voltage Converters Supply Upon the Induction Motors Behaviour 

      Alexandru, Decebal; Enache, Monica-Adela; Marinas, Paul ("Dunarea de Jos" University of Galati, 2002)
      The induction motors supply by converters leads to a distorted regime accompanied by some parasite torques and some supplementary losses. These aspects are emphasized further on because their quantitative determinations ...
    • Modeling, Identification and simulation of a Lighting Control System 

      De Keyser, Robin; Ionescu, Clara Mihaela ("Dunarea de Jos" University of Galati, 2002)
      This paper presents the results of the first phase in the design of a control system for closed-loop regulation of the light amount in office-building rooms. This project is a joint development of Ghent University and ...
    • New Power Optimization Posssibilities 

      Bitoleanu, Alexandru; Popescu, Mihaela ("Dunarea de Jos" University of Galati, 2002)
      In this paper there are given a few mathematical relations for the power analysis in un-sinusoidal regime. If the voltage is sinusoidal and the current is unsinusoidal, the apparent power will be ascertained by the active ...
    • Numerical Treatment of some Complex Dynamic Processes of Saturated Induction Machine 

      Câmpeanu, Aurel; Ionescu, Augustin-Iulian; Câmpeanu, Toma ("Dunarea de Jos" University of Galati, 2002)
      Three variants for the mathematical models of the saturated induction machine (the exact one, the classical one and the simplified one) are used for the analysis of the reversal process combined with one short mechanical ...
    • On the Snubber Influence to the Switching and Conduction Losses in a Converter Using Switched Capacitor 

      Judele, Stelian; Solea, Răzvan; Dugan, Viorel ("Dunarea de Jos" University of Galati, 2002)
      The paper deals to design and to compute the snubber parameters influence on the switching and conduction losses of the transistors (IGBT) used as bidirectional switches in a converter with switched capacitor. The converter ...
    • Optimal Control Structure for Variable Speed wind Power System 

      Cutululis, Nicolaos Antonio; Munteanu, Iulian; Ceangă, Emil; Culea, Mihai ("Dunarea de Jos" University of Galati, 2002)
      This paper presents an optimal control structure for variable speed, fixed pitch wind turbine. The control objective results from the optimization criterion that includes two contradictory demands: maximization of the ...
    • Real Time wind Turbine Simulator Based on Frequency Controlled Servomotor 

      Cutululis, Nicolaos Antonio; Ciobotaru, Mihai; Ceangă, Emil; Roşu, Mina Emil ("Dunarea de Jos" University of Galati, 2002)
      This paper is a contribution to the development of a real time wind turbine simulator. The simulator is designed to generate wind power on its shaft, and provide the static and dynamic characteristics of a given turbine. ...
    • Simple Approach for Induction Motor Control Using Reconfigurable Hardware 

      Imecs, Maria; Incze I., Ioan; Szabó, Csaba ("Dunarea de Jos" University of Galati, 2002)
      The paper deals with rotor-field-oriented vector control structures for the induction motor drives fed by the so-called tandem frequency converter. It is composed of two different types of DC-link converters connected ...
    • A Simulation Platform to Model, Optimize and Design Wind Turbines, the Matlab / Simulink Toolbox 

      Iov, Florin; Blaabjerg, Frede; Hansen, Anca Daniela ("Dunarea de Jos" University of Galati, 2002)
      In the last years Matlab / Simulink® has become the most used software for modeling and simulation of dynamic systems. Wind energy conversion systems are for example such systems, containing subsystems with different ...
    • Some Considerations Regarding the Efficiency of the Electromechanical Motion 

      Bivol, Ion; Munteanu, Traian; Lupea, Ionel; Destobbeleer, Eric ("Dunarea de Jos" University of Galati, 2002)
      Control techniques for servo drive which run at variable speed for prolonged time is developed on the base of minimum energy dissipation in a feed-forward structure. The optimal control laws are determinate using the ...
    • Speed and Rotor Flux Estimation in Speed Sensorless Control of Induction Motor 

      Pană, Teodor; Rusu, Călin ("Dunarea de Jos" University of Galati, 2002)
      The paper compares the performances of several adaptive rotor flux and speed estimation methods used in speed sensorless vector control of induction motor. First, a short review of Luenberger, Gopinath, MRAS, Torque Error ...