PRINCIPLES OF CONSTRUCTION AND APPLICATION OF MICROWAVE SYSTEMS FOR WIRELESS ENERGY TRANSMISSION OF GROUND AND SPACE BASING

Andrei Gomozov, Vladimir Shokalo, Dmitry Gretskikh, Shamil Fadel Alvan Al-Samarai
Kharkiv National University of Radioelectroniks
andgom@rambler.ru

Abstract: The results of the investigations, carried out in Kharkiv National University of Radio Electronics, into the principles of construction of modern microwave systems for wireless energy transmission (WET) on the basis of a multipositional system of radiators (MSR) with focusing of single-stage discrete V-shaped multifrequency signals and a circular polarization rectenna, are presented.
Two versions of such systems are considered: one system is intended for power supply of ground-based remote regions, the second system is intended for energy supply of low-orbit small-size (LS) space vehicles (SV).
Кey words: wireless energy transmission, rectenna, multipositional system of radiators, electromagnetic radiation focusing, remote object, low-orbit space vehicle.

Кількість посилань 6

IMPROVING THE EFFICIENCY OF ELECTRONIC MONITORING SYSTEMS AT POTENTIALLY HAZARDOUS OBJECTS BASED ON OPTIMIZATION OF GROUP SENSORS

Borys Pospelov1, Roman Shevchenko1, Andriy Balan2
1National University of Civil Protection in Ukraine,
2Representative Office of Leica Geosystems AG

Abstract: A method for improving the efficiency of electronic monitoring systems based on the usage of group sensors for detecting critical conditions at potentially hazardous objects has been described. The problem of determining the optimal Bayesian majority rule of detection for group sensors has been solved. It has been shown that for group sensors the threshold and the majority rule of detection must be optimized jointly. The task of joint optimization of the threshold and the majority rule has been solved. The estimation of an expected gain as a result of using an optimized group sensor, that shows its high detecting efficiency, has been carried out.
Key words: electronic monitoring system of potentially hazardous objects, group sensor, critical state of an object, critical state detection indicator.

Кількість посилань 3

CURRENT DIFFERENTIAL RELAY WITH FAULT LOCATION AND SYNCHRONISATION OF MEASUREMENTS FUNCTIONS

Eugeniusz Rosolowski1, Jan Izykowski1, Murari Mohan Saha2
1Wroclaw University of Technology, Institute of Electrical Power Engineering, Wroclaw, Poland,
2ABB AB, Västerås, Sweden
eugeniusz.rosolowski@pwr.wroc.pl

Abstract: This paper considers a fault location and an analytical synchronisation of two-end measurements functions as embedded into a current differential protective relay. As a result of that, incomplete two-end measurements, i.e. a three-phase current measured at both line ends, while a three-phase voltage only from one end are considered as the input signals. The fault location and synchronisation formulae are derived with considering a distributed-parameter model of a transposed overhead line. The performed ATP-EMTP based evaluation has proved the validity of the presented algorithms and their high accuracy.
Key words: overhead power line, current differential relay, fault location, two-end measurement, analytic synchronisation, ATP-EMTP software.

Кількість посилань 7

MODELING OF DYNAMICAL REGIMES OF TWO-MOTOR ELECTRICAL DRIVES WITH DUE REGARD FOR ELASTICITY AND GAPS OF MECHANICAL TRANSDUCERS

Jumber Dochviri, Oleg Khachapuridze
Department of Electrical Engineering of Georgian Technical University
Jumber_Dochviri@yahoo.com

Abstract: In the paper a mathematical model of two-motor electrical drive with one speed controller and two thyristor converters, by taking into account elasticity's and gaps of mechanical transducers, has been constructed. By using state-space methods, the transfer functions of the object have been determined. Some recommendations for tuning of the regulators have been suggested. Dynamical characteristics that are near to the optimal ones have been obtained by applying MATLAB.
Key words: dynamics, two-motor electrical drive, modeling.

Кількість посилань 6

SERVICE-ORIENTED RESOURCE PLANNING FOR MULTISERVICE IP NETWORKS

Mykhailo Klymash, Orest Lavriv, Bohdan Buhil
Lviv Polytechnic National University
lavriv@polynet.lviv.ua

Abstract: This work proposes the analysis of service quality parameters for packet networks. The algorithm of packet processing has been developed. Research into delay and jitter for the proposed processing method has been carried out.
Key words: self-similar traffic, traffic distribution system, simulation.

Кількість посилань 5

A TWO-DIMENSIONAL MODEL OF AN ELECTROMAGNETIC ACCELERATOR

Orest Hamola, Marta Hamola
Lviv Polytechnic National University
oresthamola@polynet.lviv.ua

Abstract: The mathematical model of an accelerator’s magnetic field, which takes into account its symmetry, the nonlinearity of an armature characteristic B(H), and eddy currents, has been investigated. The model has been developed on the basis of the finite elements method. The armature that moves under the applied Ampere’s force has been represented as a movable distribution of magnetic permeance.
Key words: coil, eddy currents, electromagnetic accelerator, ferromagnetic core (armature).

Кількість посилань 7

COMPUTATION OF POSITIVE STABLE REALIZATIONS FOR DISCRETE-TIME LINEAR SYSTEMS

Tadeusz Kaczorek
Faculty of Electrical Engineering, Bialystok University of Technology, Poland
kaczorek@isep.pw.edu.pl

Abstract: Sufficient conditions for the existence of positive stable realizations for given proper transfer matrices are established. Two methods are proposed for determination of the positive stable realizations for given proper transfer matrices. The effectives of the proposed procedures is demonstrated on numerical examples.
Key words: computation, initial condition, observability, positive, discrete-time, linear, system

Кількість посилань 16

SYMMETRY OF DIFFERENTIAL EQUATIONS OF ELECTROMAGNETIC FIELD IN IMMOVABLE MEDIUM

Vasyl Tchaban
Lviv Polytechnic National University
vtchaban@polynet.lviv.ua

Abstract: In the paper it is shown that differential equations describing an electromagnetic field in solid immovable media based on the vectors of intensities of electric or magnetic fields in most cases practically coincide with those based on the vector-potential of the electromagnetic field. This special feature essentially simplifies practical analysis, beginning with the determination of border conditions. The expressions for static and differential parameters of the medim are given.
Key words: differential equations, vectors and vector-potential of electromagnetic field, non-linearity, anisotropy, static and differential parameters, symmetry.

Кількість посилань 17

INVESTIGATION OF THE INFLUENCE OF CAPACITOR IN THE EXCITATION WINDING CIRCUIT OF A SYNCHRONOUS MOTOR ON ITS STARTING TORQUE

Vasyl Malyar, Iryna Dobushovska
Lviv Polytechnic National University
svmalyar@polynet.lviv.ua, i.dobushovska@gmail.com

Abstract: The problem of mathematical modelling the asynchronous modes of synchronous motors with a capacitor in the excitation winding circuit is discussed. A technique for studying the effect of capacitance value on the starting torque of the motor has been proposed. The task has been solved as a boundary value problem for a non-linear system of power balance equations, in which the magnetic flux linkage is calculated on the basis of the magnetic field computation using the magnetic circuit theory.
Key words: synchronous motor, starting torque, capacitor, boundary value problem.

Кількість посилань 7

CONTROL OF CHARGE OF SUPERCAPACITOR’S BATTERY AS DEVICE WITH DIFFUSION PROPERTIES

Victor Busher
Odesa National Polytechnic University

Abstract. There has been analyzed the charge processes in a battery of series-connected supercapacitors and developed the fractional differential-aperiodic regulator for a model of fractionally-integrated section for SIMULINK with high accuracy and fast performance at the fixed calculation step. The proposed model is an improved version of the supercapacitor that takes into consideration the diffusive processes and parameters’ variation on change of the current polarity.
Key words: control, supercapacitor’s battery.

Кількість посилань 5

SCANNING TELEVISION OPTICAL MICROSCOPE FOR BIOLOGICAL MICROOBJECTS RESEARCH

Volodymyr Shkliarskyi, Ivan Prudyus, Anatoliy Pedan
Lviv Polytechnic Notional University
shkliarskyi@polynet.lviv.ua

Abstract: Ways of developing a scanning television microscope, which can be used for the investigation of biological microobjects, have been analyzed. The capabilities of the microscope are extended due to a raster formation in the television mode and little-frame mode. Ways of changing the raster size while maintaining the microobject image resolution have been proposed.
Key words: Scanning microscope, electron beam tube, microobject.

Кількість посилань 10

CREATING ELECTRONIC DEVICE MACROMODELS BY QUADRATIC AND CHEBYSHEV APPROXIMATION

Yaroslav Matviychuk1, Peter Malachivsky2, Roman Hasko1
1Lviv Polytechnic National University,
2Leading researcher, Centre for Mathematical Modeling IAPMM National Academy of Sciences of Ukraine
matv@ua.fm, psmal@cmm.lviv.ua, r.hasko@gmail.com

Abstract: In the article the problem of mathematical macromodeling of electronic devices has been considered. The results of macromodeling by the least squares approximation and the Chebyshev approximation for frequency detectors, multivibrators, and oscillators have been shown. The efficiency of the method of least squares in reproducing the original signal macromodels of nonlinear electronic devices has been proved.
Key words: mathematical macromodeling, electronic devices, least squares and Chebyshev approximation.

Кількість посилань 5