Power Quality in Power Systems and Electrical Machines, Second Edition ( TQL.com )

POWER QUALITY IN POWER SYSTEMS AND ELECTRICAL MACHINES This page intentionally left blank POWER QUALITY IN POWER SYSTEMS AND ELECTRICAL MACHINES Second Edition MOHAMMAD A.S MASOUM EWALD F FUCHS AMSTERDAM • BOSTON • HEIDELBERG • LONDON NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Academic Press is an imprint of Elsevier Academic Press is an imprint of Elsevier 125 London Wall, London, EC2Y 5AS, UK 525 B Street, Suite 1800, San Diego, CA 92101-4495, USA 225 Wyman Street, Waltham, MA 02451, USA The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, UK Copyright © 2015, 2008 Elsevier Inc All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein) Notices Knowledge and best practice in this field are constantly changing As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein For information on all Academic Press publications visit our website at http://store.elsevier.com/ ISBN: 978-0-12-800782-2 Printed in The United States of America 08 09 10 11 12 CONTENTS Preface Acknowledgments Introduction to Power Quality 1.1 Definition of power quality 1.2 Causes of disturbances in power systems 1.3 Classification of power quality issues 1.4 Formulations and measures used for power quality 1.5 Effects of poor power quality on power system devices 1.6 Standards and guidelines referring to power quality 1.7 Harmonic modeling philosophies 1.8 Power quality improvement techniques 1.9 Summary 1.10 Problems References Additional bibliography Harmonic Models of Transformers 2.1 Sinusoidal (linear) modeling of transformers 2.2 Harmonic losses in transformers 2.3 Derating of single-phase transformers 2.4 Nonlinear harmonic models of transformers 2.5 Ferroresonance of power transformers 2.6 Effects of solar-geomagnetic disturbances on power systems and transformers 2.7 Grounding 2.8 Measurement of derating of three-phase transformers 2.9 Summary 2.10 Problems References Additional bibliography Modeling and Analysis of Induction Machines 3.1 3.2 Complete sinusoidal equivalent circuit of a three-phase induction machine Magnetic fields of three-phase machines for the calculation of inductive machine parameters xi xiii 4 20 57 57 65 67 89 90 101 104 105 108 109 118 128 145 161 165 179 194 195 201 205 207 211 219 v vi Contents 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 Steady-state stability of a three-phase induction machine Spatial (space) harmonics of a three-phase induction machine Time harmonics of a three-phase induction machine Fundamental and harmonic torques of an induction machine Measurement results for three- and single-phase induction machines Inter- and subharmonic torques of three-phase induction machines Interaction of space and time harmonics of three-phase induction machines Conclusions concerning induction machine harmonics Voltage-stress winding failures of ac motors fed by variable-frequency, voltage- and current-source pwm inverters 3.12 Nonlinear harmonic models of three-phase induction machines 3.13 Static and dynamic rotor eccentricity of three-phase induction machines 3.14 Operation of three-phase machines within a single-phase power system 3.15 Classification of three-phase induction machines 3.16 Summary 3.17 Problems References Additional bibliography Modeling and Analysis of Synchronous Machines Sinusoidal state-space modeling of a synchronous machine in the time domain 4.2 Steady-state, transient, and subtransient operation 4.3 Harmonic modeling of a synchronous machine 4.4 Summary 4.5 Problems References Additional bibliography 225 229 233 236 242 260 268 272 272 293 297 297 298 300 300 308 312 313 4.1 Interaction of Harmonics with Capacitors 5.1 Application of capacitors to power-factor correction 5.2 Application of capacitors to reactive power compensation 5.3 Application of capacitors to harmonic filtering 5.4 Power quality problems associated with capacitors 5.5 Frequency and capacitance scanning 5.6 Harmonic constraints for capacitors 5.7 Equivalent circuits of capacitors 5.8 Summary 5.9 Problems References 317 322 384 411 411 424 427 429 431 443 444 448 470 473 478 482 483 487 Contents Lifetime Reduction of Transformers and Induction Machines 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 Rationale for relying on the worst-case conditions Elevated temperature rise due to voltage harmonics Weighted-harmonic factors Exponents of weighted-harmonic factors Additional losses or temperature rises versus weighted-harmonic factors Arrhenius plots Reaction rate equation Decrease of lifetime due to an additional temperature rise Reduction of lifetime of components with activation energy E ¼ 1.1 eV due to harmonics of the terminal voltage within residential or commercial utility systems 6.10 Possible limits for harmonic voltages 6.11 Probabilistic and time-varying nature of harmonics 6.12 The cost of harmonics 6.13 Temperature as a function of time 6.14 Various operating modes of rotating machines 6.15 Summary 6.16 Problems References Power System Modeling under Nonsinusoidal Operating Conditions 7.1 Overview of a modern power system 7.2 Power system matrices 7.3 Fundamental power flow 7.4 Newton-based harmonic power flow 7.5 Classification of harmonic power flow techniques 7.6 Summary 7.7 Problems References Impact of Poor Power Quality on Reliability, Relaying and Security 8.1 Reliability indices 8.2 Degradation of reliability and security due to poor power quality 8.3 Tools for detecting poor power quality 8.4 Tools for improving reliability and security 8.5 Load shedding and load management 8.6 Energy-storage methods 8.7 Matching the operation of intermittent renewable power plants with energy storage 8.8 Summary 8.9 Problems References Additional bibliography 489 492 492 493 508 510 512 512 514 515 517 524 525 525 528 561 562 569 573 575 578 594 623 659 671 671 679 681 684 687 720 739 755 755 756 757 758 771 778 vii viii Contents The Roles of Filters in Power Systems and Unified Power Quality Conditioners 9.1 Types of nonlinear loads 9.2 Classification of filters employed in power systems 9.3 Passive filters as used in power systems 9.4 Active filters 9.5 Hybrid power filters 9.6 Block diagram of active filters 9.7 Control of filters 9.8 Compensation devices at fundamental and harmonic frequencies 9.9 Unified power quality conditioner (UPQC) 9.10 The UPQC control system 9.11 UPQC control using the park (DQO) transformation 9.12 UPQC control based on the instantaneous real and imaginary power theory 9.13 Performance of the UPQC 9.14 Summary References 10 Optimal Placement and Sizing of Shunt Capacitor Banks in the Presence of Harmonics 10.1 10.2 10.3 10.4 Reactive power compensation Common types of distribution shunt capacitor banks Classification of capacitor allocation techniques for sinusoidal operating conditions Optimal placement and sizing of shunt capacitor banks in the presence of harmonics 10.5 Summary References 11 Power Quality Solutions for Renewable Energy Systems 11.1 11.2 11.3 11.4 11.5 11.6 11.7 11.8 11.9 11.10 11.11 Energy conservation and efficiency Photovoltaic and thermal solar (power) systems Horizontal – and vertical-axes wind power (WP) plants Complementary control of renewable plants with energy storage plants AC transmission lines versus DC lines Fast-charging stations for electric cars Off-shore renewable plants Metering Other renewable energy plants Production of automotive fuel from wind, water, and CO2 Water efficiency 779 782 785 786 810 813 818 820 842 848 854 855 859 872 882 885 887 890 893 897 921 957 957 961 964 975 990 1024 1055 1055 1056 1056 1057 1058 1058 Contents 11.12 Village with 2,600 inhabitants achieves energy independence 11.13 Summary 11.14 Problems References Appendix Appendix Appendix Appendix Index 1058 1060 1060 1078 1085 1091 1101 1103 1105 ix Index multiple faults, 167–168 service continuity, 166 static grounding, 178 system grounding, 166 ungrounded system, 166 Guidelines, 57–64 H Harmonic power flow (HPF), 623–658, 676–678 accuracy of decoupled HPF, 661–662, 669 algorithm, 627–631, 637–638 assembly of equations, 627–631 bus admittance matrix, 623–625 classification of HPF techniques, 624 classification of time harmonics, 625 correction bus vector, 656 current balance at fundamental frequency, 628 current balance at harmonic frequency, 629 decoupled HPF, 661–662 fast HPF, 662–664 fuzzy HPF, 664–665 harmonic (bus) admittance matrix, 623–625, 639 harmonic frequencies, 624 harmonic Jacobian entry formulae, 635–638 harmonic Jacobian matrix, 650, 677–679 harmonic power definitions, 623–625 linear bus, 627 mismatch vector, 631, 646 modeling of linear loads, 626 modeling of nonlinear loads, 625–626, 641 (see also Loads) modified fast decoupled HPF, 664 modular HPF, 667–669 negative sequence, 26 Newton–Raphson approach, 631–638 nonlinear bus, 625–627, 675 phase shift, 113–114 probabilistic HPF, 665–667 space, 27 spatial, 27 weak power system, 675 zero sequence, 26–27 Harmonics, 21–27 admittance matrix, 578–579 (see also Harmonic power flow) cancellation, 68 characteristic, 26 cost of harmonics, 525 current calculation, 69, 73–76 domain simulation, 65–66 even, 24, 232 even space harmonics, 270 factor, 30–31 flicker, 20, 876 form factor (FF), 30 frequency conversion, 400–401 frequency variations, 20, 706–707, 760 harmonic domain simulation, 66 harmonic factor (HF), 31 harmonic filter, 74–77 harmonic power, 109–117 interaction of space and time harmonics, 268–272 interharmonic, 25–26, 69 lowest order harmonic (LOH), 31 modeling harmonic sources, 65–67 negative sequence, 26–27 noninteger, 17, 270 noninteger space harmonics, 270 notching, 17 odd, 24 order, 24 positive sequence, 26–27 propagation, 5f, 170–171 resonance, 97, 101, 145–160, 189–190, 450–452, 893, 893 (see also Resonance) simulation techniques, 66–67 space, 27, 229–232 spatial, 27 subharmonic, 25, 96 THD, 31–32 (see also Total harmonic distortion) time, 27, 233–235 time-domain simulation, 65–66 time-varying nature of harmonics, 19, 27, 524 transients, 9–10 triplen, 24–25, 232 uncharacteristic, 26 unpredictable events, voltage calculation, 69, 73–76, 89–90 weighted-harmonic factors, 508–509 (see also Aging) zero sequence, 26–27 Heat flow, 554–555 conduction, 554–555 convection, 555–556 radiation, 555–556 Heuristic method, 900 High-voltage DC (HVDC) transmission, Hunting, 316 1109 1110 Index Hybrid MSS-LV algorithm, 929 I Imbalance, 872 Impedance, 579t Inductance, 579t Induction machine, 209–272 additional temperature rise due to harmonics, 510–511 (see also (Aging) aging, 491, 491, 491 (see also (Aging) asynchronous torques, 272 auxiliary winding, 247 classification, 298–300 control, 302, 564 conventional harmonic model, 294 critical speeds, 303–304 current-source-fed induction motor, 262–263, 305 double-squirrel cage circuit, 298, 300 doubly fed induction generator, 768f dynamic rotor eccentricity, 297 (E/f) control, 302, 564 equivalent circuit, 212, 213f flux distribution, 220f forward rotating fundamental mmf, 231 forward rotating harmonic mmf, 235f fractional horsepower, 245 fundamental slip, 213, 236–237 fundamental torque, 214, 236–242, 305 harmonic current, 308 harmonic (equivalent circuit) model, 236f harmonics in stator teeth and yokes, 248–250 harmonic slip, 237–241 harmonic torque, 236–242 harmonic voltage, 308 interaction of time and space harmonics, 269 interharmonic torque, 260–268, 305 iron-core loss resistance, 247 leakage flux loss, 294 linear (sinusoidal) model, 212f magnetic fields, 219–224 magnetizing impedance, 246 main-phase winding, 247 measured harmonic losses, 505 (see also Aging) measurements, 242–260 noninteger space harmonics, 270 nonlinear circuit parameters, 244–250 nonlinear harmonic models, 293–297 operation modes, 528–561 (see also Operating modes of rotating machines) overfrequency, 303 overvoltage, 217, 303 permanent-split-capacitor (PSC), 244 phasor diagram, 301 reduction of harmonic torque, 545–546, 564–565 reflected harmonic slip, 239–242 rotating magnetomotive (mmf) force, 270 rotor core loss, 294 rotor eccentricity, 297 rotor impedance, 245–246 search coil, 248–249, 248f single-phase, 242–260 sinusoidal equivalent circuit, 211–219 spatial (space) harmonics, 229–232 spectral-based harmonic model, 295–297, 296f stability, steady-state, 225–228, 300 starting current, 224f starting performance, 224f starting torque, 219 static rotor eccentricity, 297 stator impedance, 245 stator teeth, 248–250 stator yoke (backiron), 248–250 subharmonic torque, 260–268, 305 synchronous torques, 271–272 temperature-rise calculation, 556–560 three-phase, 213–214 three-phase machine operated on single-phase system, 297–298 time harmonics, 233–235 torque, three-phase, 225 turns ratio, 247 underfrequency, 303 undervoltage, 216, 302 unstable operation, 225 (V/f) control, 302, 564 voltage-source-fed induction motor, 260–262, 307 voltage stress, 305–307 weighted-harmonic factors, 493–507 (see also Aging) winding failures, 272–293 winding stress, 275–277, 307 winding switching, 228f Inductor, 195 Inverter Index current-controlled voltage-source inverter, 53f, 332f, 422f current-source inverters (CSI), 782–783 paralleling with power system, 350f phasor diagram of inverter, 332–333 pulse-width-modulated (PWM) inverters, 52–55, 191–192, 272–293, 373, 948, 984, 1102 six-step inverter, 45–46, 187–188 Islanding, 743–745 definition of problem, 745–746 intentional islanding, 743–751 solution approach, 746–751 IÁT product, 35 J Jacobian matrix, 603, 631–632, 675, 677–679 fundamental Jacobian matrix, 603 harmonic Jacobian matrix, 632, 677 K Kelvin, 514 K-factor, 119–121, 196–197 sensitivity, 123 L LabVIEW, 738–739 Lanchester-Betz equation, 771 Lifetime rated, 514 reduction, 492, 492–493, 493–507, 508–509, 510–511, 512, 512–513, 514–515, 515–517, 517–524, 524, 525, 525–527, 528–561, 561–562 (see also Aging) Lightning, 10, 10f, 170–171, 173–174 arrester operation, 173–174 insulator flashover, 170–171 PSpice solution, 171, 171f strike, 10, 10f surge, 307 Load flow, 594–623 (see also Power flow Loads, 578, 782–784 linear loads, 578 load point, 685f load sharing, 760–762 modeling linear loads at harmonic frequencies, 626 nonlinear loads, 578, 782–784 (see also Nonlinear loads) Local variation (LV), 927–928 Losses breakdown, 215f conventional approach (PLoss ¼ Pin – Pout), 185, 730 direct loss measurement, 185 harmonic, 108 indirect loss measurement, 115 maximum error analysis, 183 new approach (pcu¼i’2(v1–v’2) and pfe ¼ v1(i1–i’2)), 763–764 M Magnetic field strength, 692 calculation, 111f, 161 Magnetic force calculation, 178 Magnetics, 112–114 major loop, 112, 112f minor loop, 112, 112f Manufacturing regulations, 6–7 Mathematica solutions, 152, 275–277, 285, 707 MATLAB solutions, 152, 275–277, 285, 707 Maximum sensitivities selection (MSS), 924–927, 944 convergence, 927 MMS algorithm, 925–926 sensitivities functions, 924–925 Measurement, 19f, 21–23f, 25f, 179–194, 242–260, 496–498, 497f, 504f, 506f, 722–730 accuracy, 183–185 computer sampling, 248–250 current, 247–248 errors, 183, 184t flux density, 248–250 uncertainty, 201 voltage, 247–248 Motoring, 303–304 N National Electrical Code (NEC), 177 Newton–Raphson, 595–601 (see also Power flow Nonlinear loads, 782–784 current-source (current-fed or current-stiff) nonlinear loads, 782–783, 783f frequency spectrum of an unbalanced, three-wire three-phase nonlinear load, 824, 825f harmonic modeling of nonlinear loads, 625–626 modeling linear loads at harmonic frequencies, 578, 625–626, 782–783 (see also Loads) 1111 1112 Index Nonlinear loads (Continued) voltage-source (voltage-fed or voltage-stiff) nonlinear loads, 783, 783f Nonperiodic events, 687–688 NOx generation, 701 Nuclear electromagnetic pulse (NEMP), 8t O Operating modes of rotating machines, 528–561 intermittent, 530 short term, 528–529 steady-state, 528 steady-state with intermittent, 531 steady-state with short term, 530 Optocoupler, 180, 181f P Park (dq0) transformation, 320, 855–859 Partial differential equation, 567–569 Particle swarm algorithm, 912 Peak-power tracker, 756, 1072–1073 Permanent-magnet machine, 364–366, 369f cogging torque, 544–545 Permanent-magnet material, 370f coercivity, 369f neodymium–iron–boron (NdFeB), 370f residual flux density, 373–374 Permeability, 147 free-space, 162f, 198 recoil, 368, 371, 406–408 relative, 368 Phase-lock loop (PLL) circuit, 865–866 Phasor diagram, 329–333 piston compressor, 545–546 pole transformer, 195 Photovoltaic power plant, 706, 756 frequency control, 706–707 voltage control, 706–707 Point of common coupling (PCC), 63–64, 64t, 720–721, 1004f Polymer electrolyte membrane (PEM), 50 Positive-sequence voltage detector (PSVD), 867 Possible voltage spectra, 481t, 521t, 564t Power, 115, 434–436 active, 118, 434 apparent, 37 average, 434, 624 distortion, 36–38, 434–435 harmonic, 109–117 instantaneous, 822, 827–830, 865–871 reactive, 434 Power factor, 97 benefits of power-factor correction, 442–443 displacement power factor (DPF), 97, 100–101, 432–434, 483–486 power-factor correction, 431–443 total power factor (TPF), 434–436, 483–484 Power filters See Filters Power flow, 594–623 admittance (bus) matrix, 578–579, 595, 605, 671 algorithm, 600–601, 604–605 backward substitution, 589, 592–593 bus voltage vector, 596–599 distribution, 577–578 formation of table of factors, 590 forward substitution, 588, 592–593 fundamental power flow, 594–623 generation, 575–576 harmonic (see Harmonic power flow) interconnected (mesh) power systems, 594f inverse of a matrix, 616, 621 Jacobian entry formulas, 601–604 Jacobian matrix, 590–591, 610, 616 linear load, 578 load (PQ) bus, 596 matrix multiplication, 587 mismatch power, 600, 608 Newton–Raphson, 595–601 Newton–Raphson algorithm, 600–601, 604–605 nonlinear bus (see Harmonic power flow) nonlinear load, 578 nonsingular, 608f power system, 594–623 PQ bus, 596 PV bus, 596 radial power systems, 594f singularity, 585, 607 subtransmission, 577 swing bus, 596 table of factors, 590, 672–673 Taylor series expansion, 597–598 transformers, 577 transmission, 577 triangular factorization, 586–587 voltage control, 673 voltage controlled (PV) bus, 596 weak power system, 674 Power line communication, 689 Index Power quality, active-power filter, 17, 74–77 automatic disconnect, 755 backup power system, 754 batteries, 754, 1072–1073 causes, 4–7 CBEMA voltage-tolerance curve, 751–753, 766 classification, 7–20 common-mode noise, 69 custom-power devices, 846–847 custom-power devices with switching action, 431 DC offset, 15 definition, diesel-generator set, 754, 766 differential-mode noise, 69 direction of harmonic power flow, 720–721 electric noise, 17–18 emergency power system, 754, 767 energy-storage methods, 755–756 flicker, 20 fluctuation, 19–20 flywheels, 754 formulation, 20–56 frequency control, 760 frequency regulation, 754 fuel cells, 754, 767 guidelines, 57–64 high-voltage AC transmission lines, high-voltage DC transmission lines, hybrid-power filters, 813–818 hydro pumped-storage plant, 1006–1007 imbalance, 14 improvement techniques, 67–89 interharmonics, 17, 25–26, 32, 69–71, 688–689 interruption, 12 ITIC voltage-tolerance curve, 751–752, 766 lightning, 10f, 173–174 load sharing, 760–761 load shedding, 755 long-duration variation, 13–14 matching of renewable sources with energy storage, 756–757 MOSFET, 38, 42, 45 nonperiodic event, 687–688 notching, 17 overvoltage, 14, 893 passive-power filter, 799–802 peak-power tracker, 756, 1072–1073 photovoltaic (PV) power plant, 716, 756, 975–990, 1060–1062, 1067–1068 power-factor compensation, 975–976 power-frequency variation, 20 recommendations, 57–64 renewable energy systems, 964–1078 reverse-recovery current, 978, 980f ride-through capability, 751 ripple factor (RF), 30 sags, 12 SEMI F47 curve, 753, 766 short-duration variation, 11–12 single-time event, 687–688 spikes, standards, 57–64 standby power system, 754 subharmonics, 96 supercapacitors, 754 sustained interruption, 14 swells, 12 switching surges, tools for detecting poor power quality, 720–739 transients, 9–10 undervoltage, 14 unpredictable events, voltage control, 760–761 voltage fluctuation, 19–20 voltage imbalance, 14, 872 voltage pick-up, 759 voltage regulation, 751 waveform distortion, 14–18 wind power (WP) plants, 52–55 Power system, 417, 575–678 automatic disconnect, 755 frequency control, 419, 706–707 frequency regulation, 754 frequency variation, 760 intentional islanding, 743–745 interconnected, 743–745 intermittent power plants, 756–757 islanding operation, 418 load change, 417 load sharing, 719–720f, 760–762 load shedding, 755 reclosing, 344 redundant, 743–745 ride-through capability, 753 self-healing, 743–745 sequence components, 420 1113 1114 Index Power system (Continued) sequence matrices, 420 short-circuit, 420 short-circuit apparent power, 67–89 short-circuit current, 67–89 steady-state frequency variation, 417 voltage control, 706–707 voltage regulation, 751–753 voltage tolerance curve, 751–752 Power system capacity, 892 Programmable logic controller (PLC), 739–740, 842 Protection devices (PD), 685f Proximity effect, 111 PSpice solutions, 10f, 18f, 38–39, 42–43, 45–46, 50, 52–55, 171f, 174f, 435, 483 Pulse-width-modulated (PWM) inverter, 52–55 (see also Inverter Q Q-factor, 795 Quality See Power quality R Reactance, 579t Reactor, 198 interphase, 200 Real power capability (RPC), 118 Reclosing, 344 Rectifiers diode rectifier, 42 duty cycle/ratio δ, 483 firing angle α, 435 full-wave, 186 notching, 17 resonant, 189–190 silicon-controlled rectifiers (SCRs), 751, 782–783 six-step/pulse, 45–46, 187–188, 200 three-phase, 38–39, 42–43, 70f, 72t, 90–95, 91–92f, 94–95f, 186–190, 187f, 200f, 422f thyristor or SCR, 38–39, 39f twelve-pulse, 98–99 Reduction in apparent power rating (RAPR), 118 Reduction of harmonic torques, 545–546, 564–565 Relay, 688–689 frequency rate of change, 688 harmonics, 688–689 interharmonics, 17, 25–26, 32, 69–71, 72t, 688–689 operating time increase, 689f overcurrent, 688–689 set point, 688–689 underfrequency, 688 Reliability, relaying and security calculation of reliability indices, 686–687, 758 customer-oriented system indices, 684 degradation of reliability and security due to poor power quality, 687–719 demand side management, 749–751 economical evaluation of reliability, 684 error analysis, 722–730 fast interrupting switches (FIS), 740–741 fault-current limiters (FCL), 740–741, 765 harmonics and interharmonics affecting relays, 688–689 intentional islanding, 743–745 (see also Islanding) load-oriented system indices, 684 load-point reliability indices, 684 overcurrent relays, 688–689 power line communication, 689 programmable logic converter (PLC), 738–739 reliability indices, 684–687 supervisory control and data acquisition (SCADA), 738–739 tools for improving reliability/security, 739–755 uncertainty analysis, 738, 762–764 under-frequency relays, 688 Reluctance machine, 380f switched-reluctance machine, 379–380, 380f Renewable energy acceptance, 1027 acoustic noise, 976, 1005 AC transmission line, 1055 algebraic equations, 1030, 1037, 1077 ambient temperature, 1021 angular frequency, 1027, 1028f, 1029, 1031f, 1033, 1035–1037, 1048–1049, 1049–1050f, 1053–1054f, 1077–1078 annual energy yield, 971 apparent power, 1027, 1029, 1033, 1045 atomic-weight method, 1022 automobile, 1076 automotive fuel, 1058 avoided cost, 1062 axial moment of inertia, 1009, 1071–1072 base, 992–993 base apparent power, 1027, 1029, 1045 base impedance, 1045 Index base speed, 993f, 998 batteries, 976 battery cells, 1072 battery characteristic, 1073 battery storage, 1010–1013 Bavaria, 971, 1058–1059 biomass, 974 biomass power plant, 975 blade pitch angle, 1001–1002 block diagram, 985f, 1009f, 1010–1011, 1014f, 1015, 1026–1029, 1026f, 1029f, 1033, 1035, 1063f, 1067–1068, 1068f, 1073, 1077–1078, 1077f booster cooler, 1015, 1073 Britisch thermal unit (BTU), 1015–1019, 1074 bulb-type turbine, 1008 burst-current/voltage control, 972f, 1063–1064 capacitance, 989–990, 1011, 1055, 1072 capacity factor, 1006–1007, 1068–1070 Carnot efficiency, 1015–1016, 1018, 1018f, 1074 central power station, 1043–1044 charging time constant, 1029, 1033 chemical plant, 1022 circular array, 1023 coal, 973–974, 1025, 1043–1044, 1073 combined heating and electric power (CHP), 1058 combustor, 1015, 1017–1019, 1017f, 1074 comparator, 986t complementary, 1024–1055, 1078 complementary generation, 1078 compressed-air energy storage (CAES), 1015, 1073 compressed-air storage, 1013–1019, 1016f, 1073–1074, 1075f compressor, 1015–1017, 1017f, 1073–1074, 1075f connection charge, 1062 conservation of energy, 975 constant-speed wind power plants, 999 construction price, 1016, 1070, 1074 control of electronic gear, 991–999 control of frequency, 1026–1028 control of power flow based on storage plants, 1000 control of voltage, 1042–1044 convergence, 977t coolers, 1015, 1017, 1074 cooling, 966–967, 970–971, 970f, 973–974 cooling water, 1024, 1057 current-controlled voltage source inverter, 1011 custom power devices, 977–984, 989–990 cylindrical, 1070 DC-to-DC converter, 1060–1061, 1067–1068 DC transmission line, 964–965, 1049–1050 deep-cycle battery, 1062 delay, 973f, 1038, 1041f, 1049–1053f differential equations, 1027–1028, 1030, 1035, 1077 differential-mode electrical noise filter, 1066, 1067f diode, 972–973, 973f, 978, 998, 1011, 1068 displacement power factor, 987t, 1000, 1066 distillation, 1020 distributed energy sources, 1043–1044 distributed generation, 1024–1025 distributed power plants, 1025 distributed renewable sources, 1042 doubly fed induction generator (DFIG), 999, 1001–1002, 1006 droop characteristic, 1026f, 1029–1030, 1031f, 1048f, 1077–1078 duty cycle δ, 978t, 979f, 1012, 1065 dynamic system response, 1000 efficiency of appliances, 964, 972, 1061 electrical energy, 975, 1017, 1019, 1057 electric cars, 1020, 1055–1056, 1075–1076 electric trains, 1057 electrochemical capacitance, 1072 electrochemistry, 1021 electrolysis, 1019–1020, 1075–1076 electron, 990–999, 1060 electronic switching, 1060 elevation, 1006–1007, 1068–1070 Energieeinsparverordnung (EnEV), 966, 973–974 Energiewende, 973–974 energy coefficient, 969–970 Energy Conservation Act, 973–975 energy conservation in residences, 964–975 energy consumption, 964–971, 975, 1063 energy consumption in house, 966, 969, 1063 energy consumption in residence (kW/m2/a), 1063 energy density, 1019–1021, 1075–1076 energy independence, 1058–1059 energy production, 999 energy storage systems, 1005, 1054–1055 energy yield, 971, 1063 1115 1116 Index Renewable energy (Continued) energy yield as a function of latitude, 1063 environmental, 974, 1023, 1058 equivalent circuit, 994, 994t, 994f equivalent-gasoline gallons, 1020, 1076 errorsignals, 986t European effort to renewable energy, 975 European Union (EU) recommendations, 964–965 evaporation, 1006–1007, 1068–1070 extra-high voltage (EHV), 1043 fast charging stations, 1055–1056 feed-in tariff, 970f, 1056 figure of merit (FM), 1055 filter, 975, 981, 983–984, 984f, 1066, 1067f flexible AC transmission system (FACTs), 1043 floor cooling, 966–967 floor heating, 966–967, 973–974 flow battery, 976, 1005–1006, 1010 flywheel power plant, 1009, 1009f, 1070–1072, 1070f flywheel storage, 1008–1010, 1070–1072 focal point, 1022–1023, 1023f Fourier analysis, 977t, 1011, 1013 Francis turbine, 1008 frequency, 964, 986t, 989, 991, 995, 999, 1026–1030, 1026f, 1042, 1044–1053, 1049–1050f, 1053–1054f, 1077–1078 frequency and voltage control, 1026 frequency change, 1027, 1028f, 1029, 1031f, 1033, 1035–1037 frequency-dependent load, 1026f, 1027, 1029, 1029f, 1077f frequency deviations, 1026f frequency-independent load, 1026f, 1077f frequency leader, 976, 1025, 1030, 1032, 1034f, 1044, 1078 frequency perturbation, 1045 frequency variation, 1026, 1032, 1038, 1044–1053, 1050f, 1053f fuel cells, 1020–1022, 1075–1076 furling of blades, 999–1000 gallons, 1021–1023 gallons/year, 1021 gas turbine, 988, 1015–1019, 1017f, 1073–1074 gate, 978 gating signal, 986t, 1066 generation capability, 1025 geological formation, 1057 geomagnetic fields, 1057 geothermal, 974, 1057 geothermal potential, 1057f German approach to renewable energy, 964–971, 1013, 1043, 1046, 1056 German Renewable Energy Act, 973–974 Gorlov turbine, 1008 governor time constant, 1027, 1029, 1033, 1035–1037 GPS, 1000 green energy, 1043 grid-connected mode of operation, 964–965, 976, 989, 1001–1002, 1042, 1044–1053 groundwater, 973–974, 1057 groundwater heat pump, 1057 ground water temperature, 973–974 head of water, 1006, 1069 heart pacemakers, 972 heating, 964, 966–967, 970f, 972–974, 1054, 1059, 1075–1076 heat pumps, 970, 973–974, 1059 heat rate, 1015–1017, 1019 height restrictions, 1005 heliostats, 1023–1024 high-efficiency, single-family dwelling, 965f high tariff, 967f, 970f horizontal-axis wind power plant, 1005 hydrogen, 1020–1022, 1058, 1075–1076 hydrogen-density method, 1022 hydrogen generation, 1019–1021 hydrogen storage, 1019–1021 hydro plant, 975–976, 1005–1006, 1043 hydro pump, 971, 1006 hydro-storage plant, 1006–1007 induction heat, 972 induction machine, 992–994, 992f, 998 induction-type stove, 972, 1060, 1063–1064 insolation, 984–985, 988f, 1067, 1072f, 1073 instability, 1029–1030, 1032, 1047–1048, 1077–1078 insulated-gate bipolar transistor (IGBT), 989–990, 1011–1012 insulating material, 1054 integer harmonics, 1042, 1060 integrator, 1030 interconnected power system, 964, 975–976, 1024–1025, 1025f, 1029–1030, 1077–1078 interest payment, 1062 Index intermittent operation, 976–977, 1026f, 1030–1033, 1032f, 1043, 1059 intermittent power output, 1032, 1034f inverter circuit, 1011, 1066 investment cost, 1043 islanding detection, 1000 islanding operation, 1024–1025 isochronous operation, 1026f Kaplan turbine, 1008 Lanchester–Betz–Joukowsky limit, 1005 Laplace operator, 1045 large-step, 1047–1049, 1049–1050f lead-acid battery, 1072, 1072f light emitting diode (LED), 972, 1061 limestone, 1057 limits on stability, 1046 line-commutated switch, 980f lithium-ion battery, 1022 load change, 1027, 1029, 1033 load control, 1026–1028, 1077–1078 loading, 1000, 1015, 1073 long-distance travel, 1057 long-term storage plants, 971, 1005–1006, 1013, 1030–1041, 1034f, 1078 lower switches, 986t low tariff, 967f, 970 magnetic bearings, 1070 maintenance crane, 1023 mass, 1019–1020, 1026, 1026f, 1071, 1075–1076 Mathematica, 1027–1028, 1028t, 1030–1041, 1031t, 1034f, 1038t, 1045, 1060, 1077–1078 Matlab, 1027, 1030–1041, 1077 maximum efficiency, 1005, 1058 maximum power extraction, 1001–1002, 1005 maximum power point operation, 1060 maximum power point tracking (MPPT), 989–990, 1001–1002 mechanical degradation, 1054 mechanical gears, 990, 999 medium step, 1047–1048, 1051f micro-grid power system, 964, 976, 1030–1032, 1059 mirrors, 975–976, 1022–1023, 1023f mixed-flow turbine, 1008 modulation index, 984, 987t, 989–990, 1012–1013, 1066 molten salt, 1022–1024 molten salt storage, 1022–1024 MOSFET, 972–973, 973f, 977t, 989–990 National Center for Atmospheric Research (NCAR), 1043 National Renewable Energy Laboratory (NREL), 971, 1063 natural gas, 964–966, 988, 1015, 1018, 1032–1037, 1034f, 1073, 1078 neodymium, 1005 net metering, 1056, 1060, 1062 neutron, 1022 nickel-metal hydride battery, 1076 non-constant power output, 1047–1053 non-integer harmonics, 1042, 1065 nuclear, 964–965, 974, 1026, 1043 ocean-tide renewable energy, 1057 off-shore renewable plants, 1056 off-shore wind power plant, 964–965, 1001, 1056 operating mode, 1060–1063 operating points, 1072, 1072f operation of wind farms, 999–1001 outage, 1025, 1054 over-excited, 986–987t, 987f oxygen, 1019–1022, 1075–1076 pancake-type generator, 990 parameter, 986t, 994, 994t, 1021, 1036–1038, 1054–1055, 1059, 1078 passive house, 970 pay-back period, 1062 peak-power generation, 1007, 1007f, 1016, 1044–1045, 1070, 1070f, 1074 peak-power tracker, 1067–1068 peak (maximum)-power tracker, 1060–1061 peak rectifier, 972, 1060 Pelton wheel, 1008 permanent-magnet synchronous generator (PMSG), 990, 999, 1001–1002, 1002f, 1004f, 1005 perturbation, 1043, 1045 per unit (pu), 998, 1022, 1045–1046 phase-angle current/voltage control, 972, 973f, 975, 1064–1065 phasor-data concentrator (PDC), 1000 phasor measurement units (PMUs), 1000 photovoltaic (PV), 964–971, 970f, 975–990, 1060–1063, 1067–1068 photovoltaic (PV) power plants, 984–985, 988f, 1062, 1063f, 1067–1068 P–I characteristic, 756 plants, 964–965, 974, 990–1055, 1077–1078 1117 1118 Index Renewable energy (Continued) polymer electrolyte membrane (PEM), 1021–1022 power coefficient Cp(λ,β), 1001–1002 power density, 1001–1002, 1022 power-load balance, 1042 power plant for residence, 1060–1062 power–speed characteristic, 992f precipitation, 1006–1008, 1068–1070 primary energy consumption, 966 prime mover, 1026, 1026f, 1033 propeller turbine, 1008 proton, 1021 PSpice, 977–978, 977t, 980f, 984, 986t, 1011–1013, 1064–1066 pulse, 977t, 978, 986t pulse-width-modulated (PWM) inverters, 984, 986t, 998, 1066 pulse-width-modulated (PWM) rectifiers, 977–983, 977t, 1065 pumped-storage hydro-power plant, 1006–1007, 1007f, 1068–1070, 1070f pumping, 975, 1006–1007, 1016, 1068–1070, 1074 pure water, 1019–1020, 1076 PV array, 984–985, 1057, 1067–1068 PV penetration, 1026 PV plants, 964–966, 971, 975, 989–990, 999–1000, 1026f, 1032–1033, 1032f, 1035, 1038, 1043–1045, 1060, 1068 radial basis function neural network (RBFNN), 1001–1002 radial power system, 1025f rain-catch area, 1008 rare earth material, 1005 reactive drop, 1049–1050 reactive power, 984, 986–987t, 987f, 1042–1044 recharging, 1016, 1074 recovery of braking energy, 1057 reformer, 1022 rejection, 1027 reliability, 1024–1025, 1043 renewable plants, 756–757, 760–761, 847–848, 1015, 1066, 1077–1078 renewable sources, 964, 973–974, 977, 988–989, 1032–1037, 1042, 1044–1053, 1078 reservoir, 1006–1008, 1015, 1068–1070, 1074 reverse-recovery current, 974, 978, 980f, 989–990 rotating mass, 1026, 1026f safety considerations, 988–989, 998 San Luis Valley of Colorado, 984–985, 988f seasonal energy efficiency ratio (SEER), 970 self-commutated switch, 977f, 1011, 1014f series turns of the stator winding, 990, 992f, 997 shadowing, 988f, 999, 1068, 1069f short-distance travel, 1057 short-term storage, 976, 1005–1006, 1009–1012, 1032f, 1035–1037, 1044–1045, 1054f, 1078 short-term storage plants, 1030–1037, 1034f, 1048f simplified grid, 1044–1046 slopes, 1032–1033 small-step, 1047–1048, 1052–1053f smart grid power system, 1042, 1059 snubber, 997 solar array, 989, 1033, 1060–1061, 1063f, 1067–1068, 1069f, 1072–1073, 1072f solar concentrator array, 1022–1023, 1023f solar panels, 989, 1056, 1061, 1067–1068 solar power generation, 1022–1023 solar thermal power plant, 1024f solid electrolyte fuel cell (SOFC), 1058 sources of energy, 974 specific energy density, 1076 specific power density, 1022 speed–torque characteristic, 992–993, 993f spherical, 1070 spokes, 1009, 1071–1072 squirrel-cage induction generator, 998, 1005 stability analysis, 1038t stable, 1000, 1031f, 1043, 1054–1055 stable frequency control, 1026f, 1032, 1034f stand-alone configuration, 1061 stand-alone mode, 976 standard flow, 1021–1022 standard liters per minute (SLPM), 1076 starting characteristic, 992–993, 993f static synchronous compensator (STATCOM), 1003f steam turbine, 988, 1026, 1029 step-down DC converter, 1060–1061 step load, 1027, 1029–1030, 1033, 1036–1037, 1077 step-up DC converter, 1067–1068, 1073 Stirling engine, 1057 storage plants, 964–965, 1005–1007, 1010, 1025, 1030–1041, 1041f, 1044–1054, 1047–1048f super-capacitor (SC), 1003–1004f, 1005–1006, 1033 Index suppression, 983–984, 984f, 989–990 synchronized phasors, 1000 synchronous condenser, 801–802, 813 synchrophasors, 1000 tax rebate, 1062 thermal solar systems, 975–976 three-phase fault, 1004f three-phase rectifier, 977–978t, 977f, 1011, 1014f, 1065 thyristor, 972–973, 973f, 978, 980f, 989–990, 1064–1065 tie, 1029–1030, 1029f, 1048–1049, 1077–1078, 1077f tiered energy rates, 975 torque–speed characteristic, 991, 992f total power factor, 1000 transfer function, 1027, 1030 transformer ratio, 1013 transformer reactance, 1045 transient excursions, 1048–1049 transient operation, 1049–1054f transient response, 1027, 1030, 1038, 1041f, 1077 transmission line power, 1044, 1049–1050, 1049f, 1051–1054f transmission loss, 976 trash-power plant, 974 tri-generation, 974 turbo generator, 1026 under-excited, 987f underground air-storage reservoir, 1015, 1073 unfurling of blades, 999–1000 unstable, 1031f upper switches, 986t US power grid, 1024–1025 valve, 1027, 1029 valve charging time constant, 1029, 1033 variable-speed drive, 975, 991, 992f, 998–999, 1006 variable-speed wind power plant, 999, 1001–1002 variation, 984–985, 1003–1004f, 1032, 1038, 1044–1053, 1049–1050f, 1052–1054f, 1078 vertical-axis wind power plant, 1005 V–I characteristic, 1061 virtual net metering, 1056 visual pollution, 1000 voltage deviations, 1043 voltage-source inverter, 985f, 986t, 1011 (V.p)/f and (V/f.N) control, 991–999 (V.p)/f control, 991–999 water efficiency, 1058 water head, 1006, 1069 water turbine, 1006–1008, 1068–1070 wave-shaping inductor, 1011 weight, 990, 998, 1007, 1009, 1021–1022, 1070, 1076 Western, Eastern and Texan generation systems (ERCOT), 1024–1025 Wildpoldsried, 1058–1059, 1059f wind energy conversion system (WECS), 1001–1002 wind farm, 975–976, 999–1001 zener diode, 986t Resistance, 579t Resonance phenomenon, 97, 101, 145, 450, 893 definition, 145 ferroresonance, 145–160 (see also Ferroresonance phenomenon) parallel, 451, 485 resonant circuit, 96, 98–99, 145–160, 794f, 893 resonant current, 152–153 resonant rectifier, 189–190 series, 451, 453 solutions to resonance problems, 152–153, 469–470, 485 subsynchronous resonance, 25 Ripple factor, 30 Root-mean-squared (rms) value, 29–30 nonsinusoidal waveform, 21, 24, 28–29 sinusoidal waveform, S Sampling techniques channel, 1085 direct memory access (DMA), 1085 interpolation, 1085 parallel, 1085 Quick BASIC, 1085 series, 1085 throughput rate, 1085 Saturation, 112, 395–406 influence SCADA, 738–739 Scanning, 471 capacitance scanning, 471 frequency scanning, 471 Security, 889 (see also Reliability, relaying and security Shaft flux, 410 1119 1120 Index Shunt capacitor banks, 887–960 benefits of reactive power compensation, 890–892 common types of distribution, 893–897 constraints, 922–923 drawbacks of reactive power compensation, 893 objective function, 923–924 optimal placement, 921–957 reactive power compensation, 890–892 Simulated annealing, 905–906 Single-time event, 687–688 Skin effect, 110 Stability, 225–228, 300 Standards, 6, 57–64 EN 61000, 62t IEC, 59t, 61–62 IEC 61000, 1–104, 59t IEEE, 59t IEEE-519, 62–64, 81, 97 Storage plants, 420–421, 766 battery, 1072–1073 compressed-air, 1073–1074 diesel generator, 766 flywheel, 1009 fuel cell, 767 hydro (pumped-hydro), 1006–1007 supercapacitor, 420–421 superconducting coil (magnetic storage), 198 Superconductor, 198 coil, 198 Susceptance, 579t Switches, 740–741 fast-interrupting switch (FIS), 740–741 fault-current limiter (FCL), 741–742, 765 Synchronous machine, 313–428 (see also Operating modes of rotating machines abc reference system, 355, 399–400 amortisseur, 316 asymmetric load, 391 balanced three-phase short circuit, 355, 383f, 412–413 bearing currents, 410 breadth factor, 339 consumer reference frame, 330 cross coupling, 334f current densities, 381 current-source fed machine, 386–387 current spectrum, 390 cylindrical-rotor machine, 338–339 damper bar currents, 357 damper winding, 344 delta winding connection, 404–405 design guidelines, 381 displaced stator windings, 412 distribution factor, 339 dq0 reference system, 344 eccentricities of rotor (dynamic, static), 406–410 electrical equations, 318–320 equivalent circuit, 329f field winding current, 386–387 flux distribution, 327f forces during short circuit, 322–323 frequency conversion, 401 generator reference frame, 331 harmonic equivalent circuit, 385f, 396 imbalance, 395–406 line-to-line short circuit, 344, 413–414, 420 line-to neutral short circuit, 355, 413–414 magnetic field (for calculation of either L’d or X’d), 328 magnetic field (for calculation of either Ld or Xd), 325f magnetic field (for calculation of either Lq or Xq), 325f magnetic field (full-load), 326f magnetic field (no-load), 369f magnetic field (permanent-magnet machine), 327f magnetic field (steady-state short-circuit), 324f magnetic field (subtransient short-circuit), 383f magnetic saturation, 320–321 maximum flux densities, 381 Maxwell stress, 382 mechanical equations, 320 model applied to power flow, 384–385 motor reference frame, 330 negative-sequence reactance, 385 nonlinear load, 379, 392–394 non-salient pole machine, 333–335 operation modes, 386–387 out-of-phase synchronization, 344, 414 permanent-magnet machines, 364–366, 369f phasor diagram, 329–333 pitch factor, 339 positive-sequence reactance, 385 power quality, 404 reclosing, 344 reduction of harmonic torques, 399–400, 412–413 Index relation between induced and terminal voltages, 381 rotor winding, 340f round-rotor machine, 329–333, 411–412 salient-pole machine, 332–333, 344, 412 saturation, 395–406 shaft flux, 410 sinusoidal dq0 modeling, 322 sinusoidal state-space modelling, 317–322 stability, 330, 355 stacking factor, 381 starting performance, 414–415 stator winding, 339f steady-state operation/analysis, 322–383 subtransient operation, 322 subtransient reactance, 329f switching substations (SS), 323f synchronizing and damping torques, 355, 413–414 synchronous reactance, 338–339 terminals, 344–355 torque, 320, 413–415 transient operation, 322–383 transient reactance, 328–329 two displaced stator windings, 413f unbalanced load, 355 voltage ripple, 364–366 voltage-source fed machine, 387–388 voltage stress, 423–424 winding forces, 383f zero-sequence reactance, 385 T Tabu search algorithm, 912–913 Telephone form factor (TFF), 36 Telephone influence factor (TIF), 36 Temperature rise calculation, 554–556 Thermal network, 554–556 Torque, 213–214 fundamental, 214, 236–242 harmonic torque, 236–242, 545–546 reduction of harmonic torques, 545–546 starting, 219 torque pulsations, 544–545 transient, 329 Total demand distortion (TDD), 33 Total harmonic distortion (THD), 31–32 equation of THD, 31 sensitivity of THD, 932–933 suitability of THD, 946–947 Total interharmonic distortion (TIHD), 32 Total subharmonic distortion (TSHD), 33 Transformations, 856 abc transformation, 859, 863 αβ0 transformation, 859 αβ0 transformation (for sinusoidal system supplying a linear load), 861–862 αβ0 transformation (for sinusoidal system supplying a nonlinear load), 863–864 αβ0 transformation (for unbalanced system supplying a linear load), 863 dqo (Park) transformation, 856 Transformer, 577 additional temperature rise due to harmonics, 510–511 (see also Aging) aging, 562 (see also Aging) autotransformer, 164 dedicated transformer, 69–71 delta-delta, 180–181 delta-wye, 25, 90–91, 148f, 200 delta-wye grounded, 724 delta-wye ungrounded, 90–91, 182 delta-zigzag, 91–92, 198 derating, 74, 123, 179–194, 196–197 direct-loss measurement, 185, 198, 729–730 earth-surface potentials, 162–163 eddy-current losses, 112–114 equipment for tests, 185 ferroresonance, 145–160 (see also Ferroresonance phenomenon) FHL-factor, 121–123 flux distribution, 144f geomagnetic effects, 161–165 half-cycle saturation, 15f, 163 harmonic losses, 109–117 hysteresis losses, 112–114 iron-core loss, 185 K-factor, 196 loss measurement (direct method), 115–116 loss measurement (indirect method), 115 measurement errors of powers, 730 modeling (combined frequency- and timedomain), 108–109 modeling (equivalent circuit), 117f modeling (finite-difference, finite-element models), 142–144 modeling (frequency-domain model), 131–132, 134–135, 139–140 modeling (general harmonic model), 128–130 1121 1122 Index Transformer (Continued) modeling (harmonic-domain model), 128–144 modeling (nonlinear harmonic model), 128–144 modeling (sinusoidal linear model), 108–109 modeling (state-space formulation), 137–138 modeling (time-domain harmonic model), 130, 132 modeling (time-domain model), 130, 136–139 modeling (transient model), 136–139 new design, 699–702 pole transformer, 142f, 195 proximity effect, 111 real power capability (RPC), 119f reduction of apparent power rating (RAPR), 118f resonance, 98–99, 145–160, 189–190, 450 (see also Resonance phenomenon) saturation, 112, 153 sinusoidal model, 108–109 skin effect, 110 sun-spot cycles, 162 weighted-harmonic factors, 493–507 (see also Aging) wye-delta, 25, 90–91, 148f, 200f wye grounded-wye grounded, 737 wye-wye grounded, 737 wye-wye ungrounded, 180–181, 181f Transmission, 577, 699–702 audible noise, 700–701 subtransmission, 577 transmission line, 699–702 visual impact, 700 U Unbalanced, 14, 91–94, 94f, 297, 872 Uncertainty, 201, 762–765 Unified power quality conditioner (UPQC), 842–843, 848–854 compensation devices, 843–844 control (dqo), 855–859 control (instantaneous power), 859–871 control of DC voltage, 859 control of series converter, 856–858 control of shunt converter, 858–859 control system, 854–855 conventional compensation devices, 844 DC capacitor, 859 functions of UPQC, 849 left-shunt UPQC, 848 operation, 850–854 operation (unbalanced and distorted system voltage and load current), 863–864 operation (unbalanced system voltages and load current), 852–854 pattern of reference signals, 855 performance, 872–881 performance (compensation of flicker), 880 performance (compensation of voltage harmonics), 876 performance (compensation of voltage imbalance), 876 performance (current compensation), 874 performance (damping of harmonic oscillations), 876 performance (dynamic performance), 874 phase-lock-loop (PLL), 865 positive-sequence voltage detector (PSVD), 867 right-shunt UPQC, 848–849 series converter, 870–871 shunt converter, 867 structure, 849–850 Uninterruptible power supplies (UPS), V Variable-frequency converter (VFC), 272–273 Variable-frequency drive (VFD), 273, 275 Variable-speed drive, 50 Variable-speed generator, 226–228 Voltage regulation, 751 V.T product, 35 W Waveform compensation, 822 (see also Filters Waveform distortion, 14–18 Weighted-harmonic factor, 493–507 Weighting function, 561, 932–933 Winding field, 355f rotor, 340f stator, 339f two displaced stator, 413f winding stress, 275–277, 305–307, 423 winding switching, 228f Wind-power plant, 23f, 52–55, 302, 373, 767–768 direct-drive permanent-magnet generator, 364–366 doubly excited induction generator, 767–768 frequency control, 707, 761–762 low-speed generator, 368–369 voltage control, 706–707 Index Wind turbine, 771 torque, 226–228 Wye transformer configurations wye-delta, 25, 90–91, 91f, 148f, 725f, 729f, 770 wye grounded-wye grounded, 728f wye-wye grounded, 727f wye-wye ungrounded, 180–182, 181f Y X Z X-ray generation, 706 Zigzag transformer connection, 91–95, 198 Y transformer configurations Y-△, 25, 90–91, 91f, 148f, 725f, 729f, 770 Y grounded-Y grounded, 728f Y-Y grounded, 727f Y-Y ungrounded, 180–182, 181f 1123 .. .POWER QUALITY IN POWER SYSTEMS AND ELECTRICAL MACHINES This page intentionally left blank POWER QUALITY IN POWER SYSTEMS AND ELECTRICAL MACHINES Second Edition MOHAMMAD A.S... generators (e.g., wind and solar generating plants) Power Quality in Power Systems and Electrical Machines This chapter introduces the subject of electric power quality After a brief definition of power. .. events into three categories (Table 1. 2): sustained interruption, undervoltage, and overvoltage 13 14 Power Quality in Power Systems and Electrical Machines Sustained Interruption Sustained (or