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Home>Products>Journal and Reviews>I.RE.Mo.S.>Latest issue
International Review on Modelling and Simulations - April 2009 - Papers
International Review on Modelling and Simulations - Papers
by M. Serhat Keserlioglu, Ali Kircay Vol. 2. n. 2, pp. 124-128
Abstract - In this
paper, new current-mode first-order square-root-domain filters are
proposed. First-order lowpass (LP), highpass (HP), and allpass (AP) are
given in the square-root domain circuit topology. The design is based on
the state-space synthesis method with two subcircuit; square-root and
squarer/divider circuits. The natural frequency of the filters can be
electronically tuned by changing external current. Only MOS transistors
and grounded capacitor were used, and operated with single power supply
of 3V. PSPICE simulations are given to confirm the theoretical analysis.
Keywords: Current-mode circuits, Dynamic translinear circuits, Square-root-domain filters, State-space synthesis methods, First-order filters.
Vol. 2. n. 2, pp. 129-136
Abstract - PI controller is very common in the control of DVRs. However, one disadvantage of this conventional controller is its inability to improve the transient response of the system. To overcome this problem, an adaptive fuzzy logic PI controller is proposed. The controller is composed of fuzzy controller and PI controller. According to the error and error rate of the control system and fuzzy control rules, the fuzzy controller can online adjust the two parameters of the PI controller to get better transient response performance. The simulation results have proved that the proposed control method decreases the transient oscillations and greatly improve the transient and steady state response of the DVR compared to the conventional PI controller. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Transient response, PI, Adaptive fuzzy PI, Fuzzy controller, DVR, Voltage sags, Voltage swells.
Vol. 2. n. 2, pp. 137-143
Abstract - The Distributed Generators (DGs) which are operated as PV generators can be controlled in symmetrical and unsymmetrical three-phase voltage control mode. This paper presents an unbalanced three-phase backward/forward power flow solution which can handle PV nodes in both modes. The proposed algorithm is based on the power summation method and takes the power losses into account. Moreover, a mathematical formula is extracted for calculating the power losses considering the mutual coupling between three phases. Active and reactive powers are used as flow variables; therefore checking the limits of reactive power of the generator of PV node is performed in a simple and straightforward manner. The proposed algorithm for a single source distribution system is validated by testing on IEEE four-node test feeder. The results of applying proposed algorithm on a modified IEEE 34-node test feeder show the capability of the algorithm in handling PV nodes in both control modes. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Power Flow, Symmetrical Voltage Control Mode, Unsymmetrical Voltage Control Mode.
Vol. 2. n. 2, pp. 144-151
Abstract - This
paper proposes a residue factor method to find the optimal location of
the Static Var Compensator (SVC) device to damp out the inter-area mode
of oscillations. The residue method is base on the facts that it is the
product of the mode’s observability and controllability index of FACTS
controllers to the critical mode. The placements of SVC controllers have
been obtained for the base case and for the dynamic critical
contingences. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: SVC, Power system oscillations, Linear models, Eigenvalues, HSV, RHP zeros, Residues factors.
Vol. 2. n. 2, pp. 152-160
Abstract - In this paper, model of induction heater coil is presented and it is shown how to design a proper coil for induction melting. Also, effective parameters on coil design are indicated and it is shown how to consider them to improve coil design. Moreover, effects of these parameters are compared with each other. In the final section model of induction heater with voltage source inverter is presented and effective parameters on total efficiency of transmitting power to the load are investigated and experimental and theoretical results are compared in order to verify theory and equations indicated in the paper. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Induction heater, Coil design, Melting rate, Melting time, Efficiency, Voltage Source Inverter, Pulse frequency modulation.
Vol. 2. n. 2, pp. 161-171
Abstract - Depletion of fossil fuel reserves, climatic changes and fluctuation in oil prices have accelerated the development of alternative fuel vehicles amongst which hybrid electric vehicle (HEV) is recognized as the most commercially viable technology. Electric motor in an HEV allows optimum efficiency operation of the internal combustion engine to improve fuel economy and reduce vehicle emissions. This paper attempts to present an extensive bibliography on the key technologies for the design and control of hybrid vehicles, their drivetrain configurations, energy management systems and drivetrain components that result in wide-ranging vehicle performance and operation characteristics. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Battery Technology, Drivetrain Architecture, Energy Management System, Hybrid Electric Vehicle, Motor Drive.
Vol. 2. n. 2, pp. 172-177
Abstract - This study considers the influence of the magnetic core on impulse surge in the windings 110 kV transformer operating with grounded and ungrounded neutral. To reflect this effect, a combined equivalent scheme consisting of equivalent scheme of the magnetic core of transformer and the winding pattern, is proposed. We found that the effect of magnetic core on the surge in the HV (High Voltage) winding with grounded neutral don’t exceed 15% and in the LV (Low Voltage) winding reaches 40%. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Transformer, Magnetic core, Surge voltage, Modelling transformer.
Vol. 2. n. 2, pp. 178-183
Abstract - The main objectives of the work described in this paper to model and simulate the autonomous hybrid photovoltaic wind generator with battery storage (PV/WG). The more accurate and practical mathematic models for characterizing PV module, wind generator and battery storage are adopted, combining with hourly measured meteorological data and load data. The hourly wind speed, solar radiation and environmental temperature data for the typical day’s in the different seasons recorded at Algerian Meteorological Office of Bechar (South Western of Algeria (31. 38° north latitude, 2. 15° western longitude, and 0.20 albédo)) [1], have been analysed to investigate the potential of utilizing hybrid (PV/ WG) energy conversion systems used to feed with electrical energy a typical rural house at Bechar. The performance of hybrid systems consisting of different rated power wind generator, PV areas and storage battery are presented. The hourly average energy generated for the above hybrid system configuration has been compared with hourly load data of typical house. Simulation is performed in a Matlab software environment. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Hybrid, Wind Generator, Photovoltaic, Simulation, Modeling, Renewable Energy.
Vol. 2. n. 2, pp. 184-190
Abstract - Porcelain string insulators are widely used in high voltage transmission lines. Calculation of potential distribution is extensively performed to design and develop high voltage insulators. In this paper a three-dimensional (3-D) potential analysis software (Maxwell) is applied to calculate potential distribution of 230 kV porcelain suspension insulators. The effects of tower cross arm's length, number of units and corona ring parameters for I-string and II-string insulators on the potential distribution along the porcelain suspension insulators are investigated. The result can be served as a basic reference in the optimum design and proper use of line insulators in practice. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Porcelain Suspension insulators, Potential Distribution, Finite Element Method.
Vol. 2. n. 2, pp. 191-195
Abstract - In the past, medium voltage switchgear in distribution system has been protected by over-current and earth fault protection. Unfortunately, the speed problem on the traditional protection system implement makes it does not capable of protecting the system from arcing faults. Arcing faults have created severe damages to the switchgear. The issues of arcing damages have lead to the development of high speed arcing fault detector; combination of arc-flash light detection and high-speed overcurrent relay. However, one major weakness of existing arcing fault detector is that it tends to provide false tripping signal. Thus, when faults occur the unnecessary circuit breakers will trip to isolate the healthy circuit. This paper presents a proposed high selectivity design of arcing detector for a single busbar of metal enclosed medium voltage switchgear using Boolean algebra method and the design is simulated using MATLAB tool. As the result, the performance of the designed circuit breaker operation is compared with the expected circuit breaker operation. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords:Arc Protection, Single Busbar Switchgear.
Vol. 2. n. 2, pp. 196-200
Abstract - An
explicit finite difference (FD) numerical technique for solving
Laplace’s equation in spherical Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Spherical Coordinates, Shell capacitance, Finite difference, Laplace’s equation, Scale Factor.
by M. Ras lain, A. Chaabi Vol. 2. n. 2, pp. 201-204
Abstract - Much of
work show that the doping concentration in silicon varies according of
the penetration depth of dopants with different models. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Silicon, stress, piezoresistance coefficient, temperature coefficient, Temperature.
by S. Aidel, N. Boucenna, S. Belaidi Vol. 2. n. 2, pp. 205-208
Abstract - The main
objective of this paper is to describe one way of analysis of microwave
transistors, based on the transformation of the reflection coefficient
for an amplifier or a microwave oscillator. This improved method is
based on a selective optimization of the circuit. This way consist on
introducing a transformation invariant which allows to test the
appropriate transistor for a given frequency bandwidth. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Microwave oscillator, Optimization, Computer aided design, H.F transistor.
Vol. 2. n. 2, pp. 209-212
Abstract - This work presents a numerical simulation of neutral dynamics (N2) by negative corona discharge DC. The boundary element and FCT (Flux Corrected Transport) methods have been used to calculate temperature, pressure and speed. The simulation has been performed for anaxisymmetrical point-plane geometry with a hyperboloidal needle perpendicular to infinitely large conducting plate. The space and time distributions of the fundamental hydrodynamic quantities have been analysed. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Negative-corona discharge, FCT method, Numerical modelling, Transport equations.
by Triantafyllos Makarios, Hariton Xenidis, Asterios Liolios Vol. 2. n. 2, pp. 213-220
Abstract - A methodology for the evaluation of the seismic target-displacement of multistory reinforced concrete (r/c) frames in earthquake civil engineering is presented. As well known, such methodologies based on the pushover analysis and proposed in the literature are not fully documented yet. In the present paper, a methodology based on the optimum definition of equivalent non-linear single-degree-of-freedom (SDF) system and combining the static pushover procedure and the inelastic spectra analysis is first presented .Next, the methodology is applied to the actual case of an existed 3-span, two-storey r/c frame, designed by the old Hellenic Seismic Code (AK/1959). The proposed methodology comprises the following main steps: (a) Analyses of critical sections of all structural elements in order to calculate the bilinear diagram of moment-curvatures (M-c) and the diagram of moment-axial forces (M-N), (b) transformations of bilinear diagram M-c in bilinear diagram M-θ(moments-rotations) using a suitable length of each plastic hinge, (c) the gravity loads of the system are in action, (d) the static pushover analysis is performed using the force distribution of the 1st mode shape of the system, (e) Calculation of the bilinear diagram of the pushover curve of the system, (f) Calculation of the seismic target-displacement using the optimum equivalent non-linear SDF system with the inelastic response spectra, (g) Calculation of the seismic demand floor displacement of the system. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Seismic Structural Analysis, Pushover Procedure, Equivalent non-linear SDF system, Response Spectra.
by Feriel. Mekki, Meksaouine Mohamed, Mohamed. Guenfoud Vol. 2. n. 2, pp. 221-226
Abstract - This paper presents the results of theoretical study of the behaviour of anchors in a homogeneous soil (pulverulent medium).The originality of the theoretical study is in the determination of model based on the kinematics approach of the theory of the limit analysis; in the case of the criteria of Mohr Coulomb. The type of failure of the ground around the anchor, obtained by this approach, is close to the reality. Copyright © 2009 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Anchors, Geotechnical engineering, Kinematics approach, Limit analysis, Model.
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