ELEKTRYKA - Issue 3/2015 (235) - Politechnika Śląska, Wydział Elektryczny

ELEKTRYKA - Issue 3/2015 (235)

ELEKTRYKAYear LXI (2015)

QuarterlyIssue 3 (235)

Scientific Committee

CONTENTS

Foreword

Roman NIESTRÓJ, Tadeusz BIAŁOŃ, Marian PASKO: Analysis of selected dynamic properties of adaptive proportional observer of induction motor state variables
Andrzej SIKORA, Barbara KULESZ, Romuald GRZENIK: Twenty-four or twelve pulse AC/DC voltage transformation circuits
Tomasz TRAWIŃSKI, Marcin SZCZYGIEŁ, Wojciech KOŁTON, Grzegorz KŁAPYTA, Marek HOJEŃSKI, Jan MORAŃSKI, Krzysztof OZDOBA: Analysis of electrical energy consumption in chosen company in the context of the modern methods of reactive power compensation
Piotr ZIENTEK: Bearing current path in cutting drums of heading machines
Bogusław BUTRYŁO, Agnieszka CHOROSZUCHO: Numerical modeling of electromagnetic fields in large scale building structures using implicit difference scheme
Dariusz LAMBER, Paweł SOWA: Real-time management of work in LN distribution network
Janusz KURPAS, Paweł SOWA: Long-term management of network assets in distribution system operator
Wojciech BARWINEK, Arkadiusz DOMORACKI: Microprocessor system location of objects GPS/GSM
Piotr ŚWISZCZ: Deterministic models of the electric arc in selected loads in the time domain

Roman NIESTRÓJ, Tadeusz BIAŁOŃ, Marian PASKO

Instytut Elektrotechniki i Informatyki, Politechnika Śląska w Gliwicach

ANALYSIS OF SELECTED DYNAMIC PROPERTIES OF ADAPTIVE PROPORTIONAL OBSERVER OF INDUCTION MOTOR STATE VARIABLES

Summary. This paper summarizes selected results of several years of research on estimators of induction motor state variables, the example of adaptive proportional observer is discussed in detail. The analysis of selected dynamic properties includes stability analysis carried out using Lyapunov's first method for linear approximation of observer equations, transformed to the coordinate system rotating at synchronous speed and analysis of the frequency characteristics, obtained on the basis of the transfer function of the observer. The elements of observer gain matrix are given as analytical functions of parameters of the induction motor model, parameters of assumed pole placement rules and the motor speed.

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Andrzej SIKORA, Barbara KULESZ, Romuald GRZENIK

Instytut Elektrotechniki i Informatyki, Politechnika Śląska w Gliwicach

TWENTY-FOUR OR TWELVE PULSE AC/DC VOLTAGE TRANSFORMATION CIRCUITS

Summary. Different electric circuits use dc voltage created by transforming ac sinusoidal voltage supplied by the power grid. These are low- and high-power circuits, with power ranging from single watts to megawatts. The question arises what transforming system should be selected as the most efficient from technical and economical point of view. The authors have focused of 12- and 24-pulse systems utilizing multi-winding rectifier transformers. Effectivess of energy transformation has been discussed depending on the supply voltage variant. Authors have indicated that the 12- pulse system is in their opinion most advantageous.

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Tomasz TRAWIŃSKI, Marcin SZCZYGIEŁ, Wojciech KOŁTON, Grzegorz KŁAPYTA

Katedra Mechatroniki, Wydział Elektryczny, Politechnika Śląska w Gliwicach

Marek HOJEŃSKI, Jan MORAŃSKI, Krzysztof OZDOBA

Twens Sp. z o.o., Chorzów, Polska

ANALYSIS OF ELECTRICAL ENERGY CONSUMPTION IN CHOSEN COMPANY IN THE CONTEXT OF THE MODERN METHODS OF REACTIVE POWER COMPENSATION

Summary. The paper presents results of electrical energy consumption measurements (with analysis of active power, reactive power and power factor) taken by Twens in the one selected company. The results of measurements allowed for analysis of reactive power compensation level and led to the idea of modern electronic device able to compensate reactive power independently in each phase. The idea and the mathematical model of such compensator is presented as well as its simulation results.

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Piotr ZIENTEK

Instytut Elektrotechniki i Informatyki, Politechnika Śląska w Gliwicach

BEARING CURRENT PATH IN CUTTING DRUMS OF HEADING MACHINES

Summary. Reasons for generation of bearing currents in motors supplied directly from the network are presented in the paper. Waveforms of shaft voltage and bearing current are shown in Fig.1. Examples of bearing races' damages and cooperating rolling bearing elements are presented. The paper describes the methods for elimination of bearing currents in cutting drums of heading machine. The conclusions are presented in chapter 4.

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Bogusław BUTRYŁO, Agnieszka CHOROSZUCHO

Katedra Elektrotechniki Teoretycznej i Metrologii, Politechnika Białostocka

NUMERICAL MODELING OF ELECTROMAGNETIC FIELDS IN LARGE SCALE BUILDING STRUCTURES USING IMPLICIT DIFFERENCE SCHEME

Summary. The paper presents the developed algorithm of the finite-difference frequency-domain method (FDFD). The proposed concept and realization allows for detailed analysis of the phenomena related to the propagation of electromagnetic waves in the range of frequency used by wireless communication systems in building structures. The developed algorithm also takes into account the lossiness of building materials. The algorithm is suitable for large-scale computation systems by taking into account h-adaptation technique of the differential mesh. Using the example of model with complex structure the correctness of the developed algorithm was proved by verifying calculation results with those obtained by FDTD and FEM methods.

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Dariusz LAMBER

TAURON Dystrybucja S.A

Paweł SOWA

Instytut Elektroenergetyki i Sterowania Układów, Politechnika Śląska w Gliwicach

REAL-TIME MANAGEMENT OF WORK IN LN DISTRIBUTION NETWORK

Summary. Description of the system aiding the decisions of dispatchers responsible for managing operation of distribution network nN is presented in the paper. The basic assumption of the proposed system was integration of GIS-type system with real-time system SCADA nN. This was aimed at ensuring the current updating of topological data in both systems and maintaining one database containing information on network assets. The idea of designing SCADA nN system included the assumption of adopting a common way of describing the power grid, in accordance with procedure published in standard IEC61970-301:2003 and defined as CIM model. Description of the power grid according to the CIM standard made it possible to integrate different class systems and to implement dedicated functionalities used in real-time management of distribution network nN operation. The current paper presents selected and in authors' opinion the most important functions of the system, which make it possible to manage distribution network nN effectively, which ensure reliability and continuity of supply to the customers and which guarantee high standard of maintenance.

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Janusz KURPAS

TAURON Dystrybucja S.A

Paweł SOWA

Instytut Elektroenergetyki i Sterowania Układów, Politechnika Śląska w Gliwicach

LONG-TERM MANAGEMENT OF NETWORK ASSETS IN DISTRIBUTION SYSTEM OPERATOR

Summary. This paper gives an overview of issues related to management of network assets. It focuses on the particular features of the network assets: the infrastructure exhibits some characteristic attributes, which determine the approach to asset management strategy. It explains the relations between process engineering and selection of appropriate strategy of asset maintenance. It also points to the necessity of multi-criteria analysis aimed at determining the optimum asset management strategy over a full lifetime cycle.

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Wojciech BARWINEK

Instytut Metrologii, Elektroniki i Automatyki, Politechnika Śląska w Gliwicach

Arkadiusz DOMORACKI

Katedra Energoelektroniki, Napędu Elektrycznego i Robotyki, Politechnika Śląska w Gliwicach

MICROPROCESSOR SYSTEM LOCATION OF OBJECTS GPS/GSM

Summary. The article discusses issues related to utilization of GPS and GSM systems in the device called a locator. It also presents authors' own proposal of device construction, experimental studies to verify its operation and to compare designed locator GPS/GSM with competitive solutions available on the market at present.

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Piotr ŚWISZCZ

Instytut Elektrotechniki i Informatyki, Politechnika Śląska w Gliwicach

DETERMINISTIC MODELS OF THE ELECTRIC ARC IN SELECTED LOADS IN THE TIME DOMAIN

Summary. Different models of the electric arc and an analytical method of determining solution in close form for the arc voltage have been proposed in this article. This analysis has been conducted in the time domain. Deterministic approach has been used and results have been compared with measurements.

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