PQBlog

VCB Current Chopping Evaluation

Published by Electrotek Concepts, Inc., PQSoft Case Study: VCB Current Chopping Evaluation, Document ID: PQS1207, Date: June 1, 2012. Abstract: This case study presents a customer vacuum circuit breaker (VCB) current chopping transient overvoltage evaluation. A high-frequency transient model was created to simulate vacuum circuit breaker opening and closing and the resulting transient overvoltages and arresterContinue reading “VCB Current Chopping Evaluation”

Electric Shock Hazard Limitation in Water During Lightning Strike

Published by Jarosław WIATER, Białystok University of Technology Abstract: Swimming during a thunderstorm is one of the most dangerous things that can be done. Lightning regularly strikes water, and since water conducts electricity, a nearby lightning strike could kill or injure human being. This paper will present simulation results of scalar potential distribution in waterContinue reading “Electric Shock Hazard Limitation in Water During Lightning Strike”

Utility Capacitor Switching Trips Electronic Voltage Regulator

Published by Electrotek Concepts, Inc., PQSoft Case Study: Utility Capacitor Switching Trips Electronic Voltage Regulator, Document ID: PQS0301, Date: January 10, 2003. Abstract: The application of utility capacitor banks has long been accepted as a necessary step in the efficient design of utility power systems. Also, capacitor switching is generally considered a normal operation for aContinue reading “Utility Capacitor Switching Trips Electronic Voltage Regulator”

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”

Utility Capacitor Switching Fails VAX Disk Drive

Published by Electrotek Concepts, Inc., PQSoft Case Study: Utility Capacitor Switching Fails VAX Disk Drive, Document ID: PQS0408, Date: September 30, 2004. Abstract: The application of utility capacitor banks has long been accepted as a necessary step in the efficient design of utility power systems. Also, capacitor switching is generally considered a normal operation for aContinue reading “Utility Capacitor Switching Fails VAX Disk Drive”

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”

Utility Capacitor Switching Causes Nuisance Tripping of ASD

Published by Electrotek Concepts, Inc., PQSoft Case Study: Utility Capacitor Switching Causes Nuisance Tripping of ASD, Document ID: PQS0319, Date: July 18, 2003. Abstract: The application of utility capacitor banks has long been accepted as a necessary step in the efficient design of utility power systems. Also, capacitor switching is generally considered a normal operation forContinue reading “Utility Capacitor Switching Causes Nuisance Tripping of ASD”

Disturbances in Industrial Power Networks

Published by Marek KAŁUSKI, Marek MICHALAK, Mirosław PIETRANIK, Karolina SKRZYPEK, Monika SZAFRAŃSKA, National Institute of Telecommunications Abstract. The paper presents some preliminary results of the in-situ measurements of disturbances that were observed in mine underground power network. The purpose of the measurements was to identify potential interfering signals that may occur in such and similarContinue reading “Disturbances in Industrial Power Networks”

Transient Voltages at an Industrial Facility Capacitor Switching

Published by Electrotek Concepts, Inc., PQSoft Case Study: Transient Voltages at an Industrial Facility Capacitor Switching, Document ID: PQS0505, Date: June 30, 2005. Abstract: This case study describes concerns for capacitor switching transients within customer facilities. Magnification of transients initiated at higher voltage capacitors and tripping of sensitive variable frequency drive (VFD) loads are evaluated inContinue reading “Transient Voltages at an Industrial Facility Capacitor Switching”