Published by Jarosław ŁUSZCZ, Politechnika Gdańska, Wydział Elektrotechniki I Automatyki Abstract. Voltage transformers are widely used in power quality monitoring systems in medium and high voltage grids. This paper presents accuracy problems related to voltage harmonics transfer through instrument transformers. A simplified lumped-parameters wideband circuit model of the voltage transformer is proposed and verified byContinue reading “Voltage Harmonics Transfer through Medium Voltage Instrument Transformers”
Tag Archives: Voltage Sags/Surges
Hazardous Step Voltage Nearby Pole Exited by High Voltage Surge
Published by Jarosław WIATER, Politechnika Białostocka, Wydział Elektryczny, Katedra Telekomunikacji i Aparatury Elektronicznej Abstract. This paper presents a ground potential rise (GPR) and voltage difference measurement results. Measurements were made for a model of a pole installed in homogeneous ground. The test stand was built in high voltage lab. It allows safe high voltage testingContinue reading “Hazardous Step Voltage Nearby Pole Exited by High Voltage Surge”
Harmonic Current Impact on Transient Overvoltages during Filter Switching-Off
Published by Yuriy VARETSKY1, Roman PAVLYSHYN2, Michał GAJDZICA1,AGH University of Science and Technology (1), Lviv Polytechnic National University(2) Abstract. This paper focuses on the features of power filter switching-off in industrial power supply systems. The filter switching-off behavior under a large amount of a harmonic current component has been analyzed. The effect of harmonic currentContinue reading “Harmonic Current Impact on Transient Overvoltages during Filter Switching-Off”
An Analysis of the Inverter Overvoltage Generated by the Motor
Published by Algirdas BASKYS1, 2, Vytautas BLEIZGYS1, 2, Tadas LIPINSKIS1, 2Center for Physical Sciences and Technology (1), Vilnius Gediminas Technical University (2) Abstract. The overvoltage in the inverter that supplies the AC induction motor, which during the deceleration operates as a generator delivering current back into the inverter DC bus, has been investigated. The investigationContinue reading “An Analysis of the Inverter Overvoltage Generated by the Motor”
Lightning Currents in Low-Voltage Power Systems
Published by Andrzej SOWA, Bialystok University of Technology, Faculty of Electrical Engineering Abstract: Correctness estimation of lightning protection solutions require definition of lightning current distribution in conductive installations entering the structure during direct strike to lightning protection system of this structure. It concerns particularly this part of lightning current, which flows in electric installation. InformationContinue reading “Lightning Currents in Low-Voltage Power Systems”
Step Voltage Nearby Tree for Surge Current Excitation
Published by Jarosław WIATER, Białystok University of Technology Abstract. Step voltage situation arise when it is possible for a person to make simultaneous contact with a part of an electrical system which is not live under normal conditions but has become live due to the passage of current for example lightning strike one. The purposeContinue reading “Step Voltage Nearby Tree for Surge Current Excitation”
Measurement Characteristics of Voltage in Practice and Possibilities for Improvement of Voltage
Published by Alena OTCENASOVA, Juraj ALTUS, Petr HECKO, Marek ROCH,Slovakia, University of Zilina, Faculty of Electrical Engineering, Department of Power Electrical Systems Abstract. Worsened quality of supplied as well as demanded electricity causes in reality a large financial loss. The main quality parameters monitored today are voltage dips and interruptions. In this context there areContinue reading “Measurement Characteristics of Voltage in Practice and Possibilities for Improvement of Voltage”
Impact of Protective Relays on Voltage Sag Index
Published by Xinke GAO1,2 , Yapeng LIU3 , Congying WANG4,School of Electronic, Information and Electrical Engineering, Shanghai Jiao Tong University (1),Institute of Information Technology Luoyang Normal College (2),Power Supply of Qingdao Company, Shandong Electric Power Corporation (3),School of foreign language, Shanghai Jiao Tong University (4) Abstract. This paper provides the probability-assessment analysis on the characteristicContinue reading “Impact of Protective Relays on Voltage Sag Index”
Feeder Lightning Transients
Published by Electrotek Concepts, Inc., PQSoft Case Study: Feeder Lightning Transients, Document ID: PQS1101, Date: March 15, 2011. Abstract: Lightning strokes to exposed utility transmission or distribution circuits can inject a significant amount of energy into the power system in a very short time, causing deviations in voltages and currents which persist until the excess energyContinue reading “Feeder Lightning Transients”
Practical Case Study: Measurement of Power Quality Problems Caused by Common New Loads
Published by M.Sc Marko Pikkarainen, M.Sc Pekka Nevalainen, Dr. Pertti Pakonen, Prof. Pekka Verho, Tampere University of Technology, marko.pikkarainen@tut.fi ABSTRACT Two matters have strongly affected use of energy in Finland during recent years. The one is the greenhouse effect and the other is the energy price which has risen. These points have brought to theContinue reading “Practical Case Study: Measurement of Power Quality Problems Caused by Common New Loads”
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