Container Harbour in Gothenburg

Published by Jonny Carlsson, Unipower AB, Case Study: Container Harbour in Gothenburg, Date: November 8th, 2010. http://www.unipower.se The most important problem was the sags that were caused by the container cranes. The cranes created a lot of high reactive power during the start of the lift procedure. The high currents caused high demand on the transformerContinue reading “Container Harbour in Gothenburg”

Harmonic Information Management System

Published by 1. Johan ADOLFSSON, Director, Unipower AB, ja@unipower.se, 2. Peter ANDERSSON, CEO, Unipower AB, psa@unipower.se, 3. Nilesh CHINTALWAR, GM, PCI Ltd, nilesh@prime-pci.in, 4. Shital SHAH, PCI Ltd, shitalshah@prime-pci.in INTRODUCTION In the vast majority of countries today there are regulations and standards implemented that specify the maximum level of harmonic content. Some countries implement theContinue reading “Harmonic Information Management System”

Transient Detection using Peak Detectors

Published by Jonny Carlsson, Unipower AB, http://www.unipower.se Background The main problem with transients in the electrical network is that a high voltage potential might break the isolation barrier in for example cables or other equipment in the electrical network. It may also harm semiconductors that are sensitive of high voltage. A transient voltage is byContinue reading “Transient Detection using Peak Detectors”

New Technology for PQ Measurements using Auto-Calibration on Capacitive Tap on Inductive Current Transformer

Published by Jonny CARLSSON – Unipower AB, David HOLMBERG – AB Vattenfall, Jan ÖSTLUND – ABB AB Abstract A method of real-time calibrating the voltage signal from the Capacitive Tap on an ABB Current Transformer using Unipowers ‘UP-2210R/ABB Capacitive tap Module’ has produced accurate results of unbalance, harmonics and transients with no limitation in bandwidth.Continue reading “New Technology for PQ Measurements using Auto-Calibration on Capacitive Tap on Inductive Current Transformer”

Power Quality Improvement in Distributed Generation System under varying Load Conditions using PWM and Hysteresis Controller

Published Vijayshree G1, Sumathi S2, RNSIT, Bangalore,Karnataka,India(1). RNSIT, Bangalore,Karnataka, India(2) Abstract – This paper proposes a power system network modeled using a microgrid, integrated with wind and solar photovoltaic (PV) resources, along with the battery energy storage system (BESS) connected to the three-phase grid feeding the linear and nonlinear load. The simulation is carried outContinue reading “Power Quality Improvement in Distributed Generation System under varying Load Conditions using PWM and Hysteresis Controller”

Upstream Frequency Disturbance

Published by Unipower AB, Metallgatan 4C, 44132 Alingsås, Sweden. Email: info@unipower.se We have received questions about disturbances in the grid. Do we have any examples? Here is an interesting example showing how disturbances spread through the network. A major frequency disturbance occured in Scandinavia on December 1, 2005. In this comparison we have compared measuring dataContinue reading “Upstream Frequency Disturbance”

Evaluating Direction of Harmonics – Power Harmonics

Published by Unipower AB, Metallgatan 4C, 44132 Alingsås, Sweden. Email: info@unipower.se One important issue is how to trace the source of harmonics. The example below shows harmonic filters connected until 11.00 and there is no voltage distortion as expected. After 11.00 the filters were disconnected due to a fault and voltage harmonics can be seen.Continue reading “Evaluating Direction of Harmonics – Power Harmonics”

Performance Comparison of Harmonic Filters in an Industrial Power System for Harmonic Distortion Reduction

Published by 1. Estifanos Dagnew Mitiku1, 2. Gebrie Teshome Aduye2, 3. S. Abdul Rahman3, 4. Mahilet Mentesinot Abuhay4, Electrical & Computer Engineering Department, Institute of Technology, University of Gondar, Ethiopia (1, 2, 3), Industrial Engineering Department, Institute of Technology, University of Gondar, Ethiopia (4) ORCID. 1. 0000-0002-6613-3979, 2. 0000-0003-1184-9184, 3. 0000-0003-0134-8028, 4. 0000-0001-7554-8562 Abstract: TheContinue reading “Performance Comparison of Harmonic Filters in an Industrial Power System for Harmonic Distortion Reduction”

Simplified Formula for the Load Losses of Active Power in Power Lines taking into Account Temperature

Published by Stanislav S. GIRSHIN, Oleg V. KROPOTIN, Vladislav M. TROTSENKO, Aleksandr O. SHEPELEV, Elena V. PETROVA, Vladimir N. GORYUNOV, Omsk State Technical University, Omsk, Russia Abstract. The use of a simplified formula for calculation of active power losses in transmission lines taking into account the temperature in the stationary thermal regime is considered. TheContinue reading “Simplified Formula for the Load Losses of Active Power in Power Lines taking into Account Temperature”

Power Flow and Stability Analyses of a UPQC System Integrated into a Distribution Network

Published by Rachid Dehini1, Ryma Berbaoui, Othmane Abdelkhalek, Electrical engineering Department, University of Tahri Mohamed. B.P 417 BECHAR (08000), Algeria. ORCID: 1 https://orcid.org/0000-0002-8769-218X Abstract. This paper deals with the active and reactive power flow analysis inside the unified power quality conditioner (UPQC) during several cases. The UPQC is a combination of shunt and series activeContinue reading “Power Flow and Stability Analyses of a UPQC System Integrated into a Distribution Network”