Substation Transformer Switching and Dynamic Overvoltages

Published by Electrotek Concepts, Inc., PQSoft Case Study: Substation Transformer Switching and Dynamic Overvoltages, Document ID: PQS1204, Date: January 26, 2012. Abstract: This case study presents the results for a wind plant substation transformer energizing and dynamic overvoltage evaluation. Transformer inrush currents contain harmonic components that may create dynamic overvoltages if a substation transformer is energizedContinue reading “Substation Transformer Switching and Dynamic Overvoltages”

Influence of HV LC Filter on Lightning Overvoltages in Gas-Insulated Switchgear Substations

Published by Marcin SZEWCZYK, Tomasz KUCZEK, Mariusz STOSUR, Wojciech PIASECKI, Marek FLORKOWSKI, Marek FULCZYK, ABB Corporate Research Center in Krakow, Poland Abstract. In the present paper simulations of the propagation of lightning overvoltages in a typical HV GIS substation are presented. The influence of HV LC filter on maximum overvoltages peak values was analyzed. Additionally,Continue reading “Influence of HV LC Filter on Lightning Overvoltages in Gas-Insulated Switchgear Substations”

Lightning Transient Overvoltage Evaluation

Published by Electrotek Concepts, Inc., PQSoft Case Study: Lightning Transient Overvoltage Evaluation, Document ID: PQS1205, Date: January 26, 2012. Abstract: This case study presents a wind plant substation lightning transient overvoltage evaluation. A high-frequency transient model was created to simulate the lightning transients and resulting overvoltages and arrester energy duties. A high-frequency model was required toContinue reading “Lightning Transient Overvoltage Evaluation”

Voltage Harmonics Transfer through Medium Voltage Instrument Transformers

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”

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”