Introduction.......................................................................................................... 27 Definitions............................................................................................................ 27 Basic design considerations ................................................................................. 27 Planning guide for the supply and distribution system........................................ 31 Power system modernization and evaluation studies/programs .......................... 56 References............................................................................................................ 58 Bibliography ........................................................................................................ 59
Chapter 3 Voltage considerations........................................................................................................... 61 3.1 3.2 3.3 3.4
General................................................................................................................. 61 Voltage control in electric power systems ........................................................... 66 Voltage selection.................................................................................................. 78 Voltage ratings for low-voltage utilization equipment ........................................ 81
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3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13
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Effect of voltage variations on low-voltage and medium-voltage utilization equipment ........................................................................................... 82 Voltage drop considerations in locating the low-voltage secondary distribution system power source......................................................................... 86 Improvement of voltage conditions ..................................................................... 87 Phase-voltage unbalance in three-phase systems................................................. 89 Voltage sags and flicker....................................................................................... 91 Harmonics ............................................................................................................ 95 Calculation of voltage drops ................................................................................ 96 References.......................................................................................................... 107 Bibliography ...................................................................................................... 108
Introduction........................................................................................................ 109 Sources of fault current...................................................................................... 109 Fundamentals of short-circuit current calculations............................................ 112 Restraints of simplified calculations.................................................................. 115 Detailed procedure ............................................................................................. 124 Example of short-circuit current calculation for a power system with several voltage levels ......................................................................................... 138 4.7 Example of short-circuit current calculation for a low-voltage system (under 1000 V)................................................................................................... 158 4.8 Calculation of short-circuit currents for dc systems .......................................... 170 4.9 References.......................................................................................................... 170 4.10 Bibliography ...................................................................................................... 171 Annex 4A Typical impedance data for short-circuit studies.......................................................... 173 Chapter 5 Application and coordination of protective devices ............................................................ 185 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10
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Purpose............................................................................................................... 185 Analysis of system behavior and protection needs ............................................ 187 Protective devices and their applications........................................................... 192 Performance limitations ..................................................................................... 222 Principles of protective relay application [38], [40], [50] ................................. 223 Protection requirements ..................................................................................... 238 Use and interpretation of time-current coordination curves .............................. 250 Specific examplesÑapplying the fundamentals................................................ 260 Acceptance testing (commissioning), maintenance, and field testing ............... 281 Bibliography ...................................................................................................... 304
Introduction........................................................................................................ 363 System grounding .............................................................................................. 363 Equipment grounding......................................................................................... 370 Static and lightning protection grounding.......................................................... 375 Connection to earth ............................................................................................ 379 Ground resistance measurement ........................................................................ 383 References.......................................................................................................... 389 Bibliography ...................................................................................................... 389
Chapter 8 Power factor and related considerations .............................................................................. 393 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 8.10 8.11 8.12 8.13 8.14 8.15 8.16 8.17
General scope..................................................................................................... 393 Current and power flow fundamentals............................................................... 394 Benefits of power-factor improvement.............................................................. 397 Typical plant power factor ................................................................................. 402 Instruments and measurements for power-factor studies................................... 404 Techniques to improve the power factor ........................................................... 405 Calculation methods for improving power factor.............................................. 410 Location of reactive power supply..................................................................... 411 Capacitors with induction motors ...................................................................... 412 Capacitor standards and operating characteristics ............................................. 422 Controls for switched capacitors........................................................................ 425 Transients and capacitor switching.................................................................... 427 Protection of capacitors and capacitor banks..................................................... 435 Resonance and harmonics.................................................................................. 437 Inspection and field testing of power capacitors................................................ 438 References.......................................................................................................... 440 Bibliography ...................................................................................................... 442
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Chapter 9 Harmonics in power systems ............................................................................................... 443 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.8 9.9 9.10 9.11 9.12
Introduction........................................................................................................ 443 Importance of understanding effects of harmonics............................................ 443 History of harmonic problems and solutions ..................................................... 444 Definition and sources of harmonic currents and voltages................................ 445 Characteristics of harmonics.............................................................................. 447 Static power converter theory ............................................................................ 449 System response characteristics......................................................................... 455 Effects of harmonics .......................................................................................... 458 Harmonic analysis.............................................................................................. 466 Mitigation techniques......................................................................................... 467 Industry standards .............................................................................................. 471 Bibliography ...................................................................................................... 473
Chapter 10 Power switching, transformation, and motor control apparatus .......................................... 475 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8
Introduction........................................................................................................ 475 Switching apparatus for power circuits.............................................................. 478 Switchgear.......................................................................................................... 492 Transformers ...................................................................................................... 503 Unit substations.................................................................................................. 519 Motor control equipment ................................................................................... 521 Adjustable speed drives ..................................................................................... 529 Bibliography ...................................................................................................... 532
Chapter 16 Cost estimating of industrial power systems ....................................................................... 703 16.1 16.2 16.3 16.4 16.5 16.6 16.7 16.8 16.9 16.10
Introduction........................................................................................................ 703 Information required .......................................................................................... 703 Factors to be considered..................................................................................... 704 Preparing the cost estimate ................................................................................ 704 Classes of estimates ........................................................................................... 704 Equipment and material costs ............................................................................ 705 installation costs................................................................................................. 705 Other costs ......................................................................................................... 706 Example ............................................................................................................. 706 Bibliography ...................................................................................................... 707
Annex 16A Selected sources for cost-estimating information......................................................... 719 Annex A Power system device function numbers............................................................................... 721 INDEX .................................................................................................................................. 729