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Due to the complexity of power systems combined with other factors such as increasing susceptibility of equipment, power quality (PQ) is apt to waver. With electricity in growing demand, low PQ is on the rise and becoming notoriously difficult to remedy. It is an issue that confronts professionals on a daily basis, but few have the required knowledge to diagnose and solve these problems.Handbook of Power Quality examines of the full panorama of PQ disturbances, with background theory and guidelines on measurement procedures and problem solving. It uses the perspectives of both power suppliers and electricity users, with contributions from experts in all aspects of PQ supplying a vital balance of scientific and practical information on the following:frequency variations;the characteristics of voltage, including dips, fluctuations and flicker;the continuity and reliability of electricity supply, its structure, appliances and equipment;the relationship of PQ with power systems, distributed generation, and the electricity market;the monitoring and cost of poor PQ;rational use of energy.An accompanying website hosts case studies for each chapter, demonstrating PQ practice; how problems are identified, analysed and resolved. The website also includes extensive appendices listing the current standards, mathematical formulas, and principles of electrical circuits that are critical for the optimization of solutions. This comprehensive handbook explains PQ methodology with a handson approach that makes it essential for all practising power systems engineers and researchers. It simultaneously acts as a reference for electrical engineers and technical managers who meet with power quality issues and would like to further their knowledge in this area.
Handbook of Power Quality Edited by Angelo Baggini University of Bergamo, Italy Handbook of Power Quality Handbook of Power Quality Edited by Angelo Baggini University of Bergamo, Italy Copyright © 2008 John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex PO19 8SQ, England Telephone +44 1243 779777 Email (for orders and customer service enquiries): cs-books@wiley.co.uk Visit our Home Page on www.wiley.com All Rights Reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except under the terms of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London W1T 4LP, UK, without the permission in writing of the Publisher. Requests to the Publisher should be addressed to the Permissions Department, John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex PO19 8SQ, England, or emailed to permreq@wiley.co.uk, or faxed to (+44) 1243 770620. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the Publisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought. Other Wiley Editorial Offices John Wiley & Sons Inc., 111 River Street, Hoboken, NJ 07030, USA Jossey-Bass, 989 Market Street, San Francisco, CA 94103-1741, USA Wiley-VCH Verlag GmbH, Boschstr. 12, D-69469 Weinheim, Germany John Wiley & Sons Australia Ltd, 42 McDougall Street, Milton, Queensland 4064, Australia John Wiley & Sons (Asia) Pte Ltd, 2 Clementi Loop #02-01, Jin Xing Distripark, Singapore 129809 John Wiley & Sons Canada Ltd, 6045 Freemont Blvd, Mississauga, ONT, L5R 4J3 Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Library of Congress Cataloging in Publication Data Handbook of power quality / Edited by Angelo B. Baggini. p. cm. Includes bibliographical references and index. ISBN 978-0-470-06561-7 (cloth) 1. Electric power transmission—Reliability. 2. Distributed resources (Electric utilities)—Reliability. I. Baggini, Angelo B. TK3001.H34 2008 621.31—dc22 2007050178 British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library ISBN: 978-0-470-06561-7 Typeset in 10/12pt Times by Integra Software Services Pvt. Ltd, Pondicherry, India Printed and bound in Great Britain by Antony Rowe Ltd, Chippenham, Wiltshire Contents List of Contributors xix Preface xxiii 1 Frequency Variations 1 Hermina Albert, Nicolae Golovanov, Aleksander Kot and Janusz Bro˙zek 1.1 Frequency Quality Indices 3 1.2 Frequency Measuring 4 1.3 Load–Frequency Characteristics 6 1.3.1 Influence of the Frequency Variation on the Actuation Motors 6 1.3.2 Capacitor Bank and Harmonic Filters 7 1.3.3 Transformers and Coils in the Power Network 7 1.4 Influence of Frequency on Users’ Equipment 8 1.4.1 Influence of Frequency Variations on Asynchronous Motors 8 1.4.2 Influence of Frequency Variations on Parallel-Connected Condensers and Coils 11 1.4.3 Influence of Frequency Variations on Series-Connected Condensers and Coils 12 1.5 Governing of Turbine Speed 12 1.6 Frequency Control in Power Systems 16 1.6.1 Composite Load 17 1.6.2 The Generation Characteristic 19 1.6.3 The System Properties and Control Basics 20 1.6.4 Frequency Control in an Islanding System and in Interconnected Systems 22 1.6.5 Frequency Control: Primary, Secondary and Tertiary 23 1.6.6 Technical and Organizational Aspects of Load–Frequency Control 28 Bibliography 29 ● vi CONTENTS 2 Continuity of Supply 31 Krish Gomatom and Tom Short 2.1 Distribution Reliability 31 2.1.1 Customer-Based Indices 32 2.1.2 Load-Based Indices 34 2.1.3 Variation in the Utility Indices 35 2.2 Quality of Supply 36 2.2.1 Customer Service 36 2.2.2 Continuity of Supply 37 2.2.3 Voltage Quality 37 2.3 Factors Affecting Reliability Performance 40 2.3.1 Reliability Indices Reporting 41 2.3.2 Differences Based on Type of Supply 42 2.4 Improving Reliability 44 2.4.1 Utility-Side Improvement Options 44 2.4.2 Custom Power Devices 46 2.5 Costs, Markets and Value for Reliability 49 2.5.1 Size of the End-User Load and Duration Affect Cost 49 2.5.2 Market for Reliability 50 2.5.3 Value of Reliability: a Macro View 51 2.5.4 Impact of Reliability Events on End-User Productivity 53 2.5.5 Mapping Reliability to End-User Facility Operating Hours 54 Bibliography 57 3 Voltage Control in Distribution Systems 59 Andrzej Kanicki 3.1 Description of the Phenomena 60 3.2 Disturbance Sources 61 3.3 Disturbance Effects 62 3.3.1 Load Models 62 3.3.2 Voltage Drop 63 3.3.3 Voltage Stability 64 3.4 Methods of Effect Elimination 68 3.4.1 Generator Excitation Control 68 3.4.2 Transformer Ratio Control 70 3.4.3 Voltage Control by Means of Reactive Power Flow Change 72 3.4.4 Voltage Control by Means of Network Impedance Change 74 3.4.5 Node Voltage Optimization 76 3.5 Standards 76 3.5.1 Voltage Standards in Grid Normal Operating Conditions 76 3.5.2 Voltage Standards in Grid Disturbed Operating Conditions 76 ● CONTENTS vii 3.5.3 Voltage Standards in Middle- and Low-Voltage Distribution Networks 77 Bibliography 77 4 Voltage Dips and Short Supply Interruptions 79 Zbigniew Hanzelka 4.1 Description of the Phenomena 79 4.2 Parameters 82 4.2.1 Voltage Dip Duration 82 4.2.2 Magnitude of a Voltage Dip 83 4.3 Sources 87 4.3.1 Sources of Voltage Dips 87 4.3.2 Sources of Short Supply Interruptions 89 4.4 Effects 89 4.4.1 IT Equipment and Control Systems 90 4.4.2 Contactors and Relays 92 4.4.3 Induction Motors 92 4.4.4 Synchronous Motors 93 4.4.5 Variable Speed Drives 93 4.4.6 High-Pressure Discharge Lamps 94 4.5 Mitigation 94 4.5.1 Reduction of the Number of Faults 95 4.5.2 Reduction of the Fault Clearance Time 95 4.5.3 Modification of the Supply System Configuration 96 4.5.4 Voltage Stabilizers 97 4.5.5 Improvement in Equipment Immunity 98 4.6 Measurement 100 4.6.1 Principles of Measurement 100 4.6.2 Statistical Methods of Analysis 112 4.6.3 Area of Vulnerability 114 4.7 Contract 114 4.7.1 Duration of Measurements 116 4.7.2 Reference Voltage Value 116 4.7.3 Location and Method of Connection of Measuring Instrument 117 4.7.4 Technical Specifications for Measuring Instrumentation 118 4.7.5 Threshold Values for Disturbance Detection 118 4.7.6 Techniques of Reporting the Measurement Results 119 4.7.7 Methods for Aggregation of Measurement Results 119 4.8 Standards 124 4.9 Alternative Voltage Dip Indices 126 4.9.1 Indices Based on the Voltage Change 126 4.9.2 Energy-Related Indices 127 4.9.3 Others 129 ● viii CONTENTS Acknowledgement 131 Bibliography 131 5 Voltage Fluctuations and Flicker 135 Araceli Hernández Bayo 5.1 Description of the Phenomenon 135 5.1.1 Voltage Changes, Voltage Fluctuations and Flicker 135 5.1.2 Physiology of Flicker Perception 137 5.2 Parameters 138 5.3 Measurement 139 5.3.1 The IEC Flickermeter 139 5.3.2 Use of the Flickermeter 146 5.3.3 Simplified Methods for P st Assessment 148 5.4 Sources 151 5.4.1 Industrial Loads 152 5.4.2 Electrical Appliances Supplied from LV Networks 155 5.4.3 Wind Turbine Generation Systems 155 5.5 Effects 156 5.6 Mitigation Strategies 156 5.6.1 Devices Based on Decreasing Reactive Power Variations 157 5.6.2 Methods Oriented to Increase the Short-Circuit Power 160 5.6.3 Other Solutions for Flicker Mitigation 161 Bibliography 161 6 Voltage and Current Unbalance 163 Irena Wasiak 6.1 Description of the Phenomena 163 6.2 Symmetrical Components of Currents and Voltages 165 6.3 Parameters 170 6.4 Measurements 171 6.5 Sources 173 6.6 Effects 174 6.6.1 Asynchronous Motors 174 6.6.2 Synchronous Generators 174 6.6.3 Converters 175 6.6.4 Other Loads 175 6.7 Mitigation 175 6.7.1 Principle of Balancing 176 6.7.2 Static Compensators 178 6.8 Standards 181 6.8.1 Limits 181 6.8.2 Principles of Assessment 183 Bibliography 184 [...]... reserves of active power and adequate power frequency control in order to keep frequency deviations within allowed limits All equipment (installations) in the European power network are projected to operate at a rated frequency of 50 Hz Actually, due to the fact that under normal operating conditions the frequency in the power system varies in terms of power variation and according to the response speed of. .. operation The increasing development of power electronics nowadays allows the use of frequency converters in industrial processes, which provides optimum frequency for various processes The requirement of power system interconnection determines the standardization of frequency Frequency monitoring of the public network and its conservation within required limits is the duty of the system operator, who is... Variable Tariffs 19.3 Impact on Power Quality 19.3.1 Emission of Harmonic Distortion by Fluorescent Lamps 19.3.2 Emission of Harmonic Distortion by VSDs 19.3.3 Immunity of Fluorescent Lamps 19.3.4 Immunity of VSDs Bibliography 594 594 594 595 595 595 596 598 598 598 601 603 603 605 Perceived Power Quality Maurizio Caciotta 607 20.1 20.2 20.3 20 Power Quality and Rational Use of Energy Pieter Vermeyen and... 12.4 12.5 12.6 Power Quality, Reliability and Availability General Aspects of Reliability Appliances Power System Protection Alternatives 12.3.1 Power Conditioners Emergency and Standby Power Systems 12.4.1 Engine-Driven Generators 12.4.2 Microturbine-Driven Generators 12.4.3 Uninterruptible Power Systems 12.4.4 Dynamic UPS 12.4.5 Static UPS 12.4.6 Hybrid Static/Dynamic UPS 12.4.7 D.C Power Supply Systems... Institute of Electrical Power Engineering 18/22 Stefanowskigo Str 90-924 Łod´ z Poland Antoni KLAJN Wroclaw University of Technology Institute of Electrical Power Engineering ul Wyb Wyspianskiego 27 50–370 Wroclaw Poland Aleksander KOT AGH-University of Science and Technology 30-059 Kraków Al Mickiewicza 30 Poland Jonathan MANSON JEL Consulting Limited 6 Staveley Road Chiswick London W4 3ES UK G xxi LIST OF. .. Being shared by all the points in the power network, it requires centralized control or at the zone power system levels The frequency control and maintenance within allowed limits requires the existence at the system operator level of important power reserves that can be called automatically to assure at any moment a balance of the set-point frequency value of power consumption and generation An ample... VARIATIONS One of the most important indices in the operation of alternating voltage systems is the supply voltage frequency, defined as the repetition frequency of the fundamental voltage curve, measured over a specific time interval In each power system, the operational moment of the frequency value depends on the extent to which the demand is met by the power sources Setting up a nominal power system... Disturbances on Static Converters Impact of Voltage Disturbances on Static Converters Voltage Sag Susceptibility Immunization Techniques 487 487 490 490 494 Basics 15.1.1 Characteristics of Inductances and Capacitances 15.1.2 Reactive Power 15.1.3 Wattless current 15.1.4 Reactive Power Compensator 15.2 Power Factor Correction 15.2.1 Control and Regulation of Reactive Power 15.2.2 Centrally and Dispersed... Savings Studies on Cost of Poor PQ Long Interruptions Short Interruptions Voltage Dips Harmonics Other Disturbances Profiles by Sector Cost Per Event of PQ Disturbances PQ Solutions Investment Analysis to Mitigate Costs of PQ 18.11.1 Investment Analysis 18.11.2 Capital Budgeting 18.11.3 Project Classifications 18.11.4 Cost of Capital 18.11.5 The Time Value of Money 18.11.6 Future Value of a Single Cash Flow... obtained every 10 s As power frequency may not be exactly 50 Hz within the 10 s time interval, the number of cycles may not be an integer number The fundamental frequency output is the ratio of the number of integral cycles counted FREQUENCY MEASURING G 5 Figure 1.3 Assessment of frequency quality in a power system during the 10 s time interval, divided by the cumulative duration of the integer cycles . Handbook of Power Quality Edited by Angelo Baggini University of Bergamo, Italy Handbook of Power Quality Handbook of Power Quality Edited by Angelo Baggini University of Bergamo,. Techniques 537 17.4 Power Quality in the Electricity Market 537 17.4.1 Power Quality Contracts 538 17.4.2 Power Quality Market 542 Bibliography 543 18 Cost of Poor Power Quality 545 Roman Targosz. in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Library of Congress Cataloging in Publication Data Handbook of power quality / Edited