Electric Distribution Systems: Planning and Utilization

ELECTRIC DISTRIBUTION SYSTEMS......Page 5
CONTENTS......Page 7
PREFACE......Page 19
ACKNOWLEDGMENTS......Page 23
PART I: FUNDAMENTAL CONCEPTS......Page 25
1.1.1 Power System Arrangements......Page 27
1.2 DUTIES OF DISTRIBUTION SYSTEM PLANNERS......Page 29
1.3.2 Planning Policy......Page 33
1.3.3 CM......Page 34
1.3.4 Reliability Planning Standards......Page 35
1.3.5 Categories of Customer Reliability Level......Page 36
1.4.2 Power Quality......Page 37
1.4.4 Investments......Page 38
1.4.5 Distribution Losses......Page 40
1.4.6 Amount of LOL......Page 41
1.5.2 Non - Network Solutions......Page 43
1.6.2 Distribution System Confi gurations......Page 45
1.6.2.1 MV Distribution Networks......Page 46
1.6.2.2 LV Distribution Networks......Page 49
2.1 INTRODUCTION......Page 57
2.3 FORECASTING METHODOLOGY......Page 59
2.3.2 Correlation Technique......Page 60
2.3.3 Method of Least Squares......Page 62
2.3.4 STLF Techniques......Page 65
2.3.4.1 Stochastic Time Series......Page 67
2.3.5 Medium - and Long - Term Load Forecasting Methods......Page 72
2.4.1.2 Second Aspect......Page 74
2.4.2.1 Spatial Resolution......Page 75
2.4.2.3 Type of Load......Page 76
2.4.3 Load, Coincidence, and Diversity Factors ( DFs )......Page 77
2.4.4.1 Sampling Methods......Page 80
2.5 END - USE MODELING......Page 81
2.6 SPATIAL LOAD FORECAST METHODS......Page 82
2.6.1 Trend Methods......Page 83
2.6.1.1 Polynomial Curve Fit......Page 84
2.6.1.2 Saturation Growth Curve (S - Curve)......Page 87
PART II: PROTECTION AND DISTRIBUTION SWITCHGEAR......Page 91
3.1 BASIC OBJECTIVES......Page 93
3.2.1 General Means......Page 94
3.2.2.1 Step and Touch Voltage Regulations......Page 99
3.2.2.2 The Human Factor......Page 101
3.2.2.3 Measuring and Controlling Earth Resistance......Page 104
3.2.2.4 Substation Earthing Mats......Page 107
3.2.2.5 Design of Substation Earthing Mats to Meet the Step and Touch Voltage Regulations......Page 109
3.2.2.6 Design of Substation Earthing Mats Using Computer Algorithms......Page 111
3.3.1 Unearthed Systems......Page 112
3.3.4 Definitions [36]......Page 113
3.3.5 Methods of System Neutral Earthing......Page 115
3.3.6 Creating Neutral Earthing......Page 117
3.4 MV EARTHING SYSTEMS......Page 119
3.4.1 Influence of MV Earthing Systems......Page 121
3.5.1 IT Earthing System......Page 123
3.5.3 TN Earthing System......Page 124
3.5.4.1 Public Distribution Systems......Page 126
3.5.4.2 Earthing Systems of Private LV Networks......Page 127
4.1 INTRODUCTION......Page 131
4.2 SHORT - CIRCUIT ANALYSIS......Page 133
4.2.1.1 Case 1......Page 134
4.2.1.2 Case 2......Page 138
4.2.2 Calculation of Short - Circuit Current......Page 141
4.2.2.1 Symmetrical Three - Phase Short Circuit......Page 143
4.2.2.2 Unsymmetrical Short Circuits......Page 157
4.2.2.3 Sequence - Impedance Networks......Page 161
4.2.2.4 Line - to - Earth Fault (L - E Fault)......Page 168
4.2.2.5 Line - to - Line Fault (L - L Fault)......Page 174
4.2.2.6 Double Line - to - Earth Fault (2L - E Fault)......Page 175
4.2.2.7 Calculation of Minimum Short - Circuit Current in LV Distributio Networks......Page 179
5.1 INTRODUCTION......Page 187
5.1.1 Protection System Concepts......Page 188
5.2.1 Electromagnetic Relays......Page 190
5.2.3 Digital Relays......Page 191
5.3 OVERCURRENT PROTECTION......Page 195
5.3.1 Overcurrent Relays......Page 196
5.3.2.1 Time - Based Coordination......Page 199
5.3.2.2 Current - Based Coordination......Page 200
5.3.2.3 Logic Coordination......Page 202
5.3.3 Earth - Fault Protection......Page 210
5.4.1 Reclosers......Page 212
5.4.1.1 Locations of Reclosers Installation......Page 214
5.4.1.2 Series Reclosers Coordination......Page 215
5.4.2 Sectionalizers......Page 217
5.4.3 Fuses......Page 219
5.4.4 Coordination of Reclosers, Sectionalizers, and Fuses......Page 223
5.5 DIRECTIONAL PROTECTION......Page 224
5.5.1 Directional Overcurrent Relays......Page 225
5.5.2 Directional Relays Operation......Page 226
5.6 DIFFERENTIAL PROTECTION......Page 229
5.6.1 Motor Differential Protection......Page 236
5.6.3 Transformer Differential Protection......Page 237
5.6.4 Differential Protection of Buses......Page 239
5.6.5 Differential Protection of Cables and Lines......Page 240
5.7 THERMAL PROTECTION......Page 242
5.8 OVERVOLTAGE PROTECTION......Page 245
5.8.1.1 Switching Overvoltages......Page 247
5.8.1.2 Power - Frequency Overvoltages......Page 250
5.8.1.3 Lightning Overvoltages......Page 251
5.8.2.1 Insulation Coordination......Page 253
5.8.2.2 Surge Arresters......Page 255
5.8.2.3 Primary and Secondary Protection of LV Network......Page 257
6.1 NEED FOR SWITCHGEAR......Page 261
6.2 SWITCHGEAR LAYOUT......Page 263
6.2.2 Types of Switchgear Installations......Page 264
6.2.2.2 Insulation - Enclosed Switchgear......Page 265
6.3.1 Dimensioning of Insulation......Page 266
6.3.3 Dimensioning of Bar Conductors for Mechanical Short - Circuit Strength......Page 267
6.3.5 Dimensioning for Thermal Short - Circuit Strength......Page 271
6.3.6 Dimensioning for Continuous Current Rating......Page 276
6.4 CIVIL CONSTRUCTION REQUIREMENTS......Page 277
6.4.1 Indoor Installations......Page 278
6.4.3 Transformer Installation......Page 279
6.4.4 Ventilation of Switchgear Installations......Page 280
6.5.1 Definitions......Page 284
6.5.3 LBSs......Page 285
6.5.4 Earthing Switches......Page 286
6.5.5 CBs......Page 287
6.5.5.1 Principles of Interruption......Page 290
6.6.1 Isolators......Page 291
6.6.4 Fuse Switch......Page 292
6.6.5.1 Description......Page 294
6.6.5.2 Fundamental Characteristics......Page 295
6.6.5.3 Selection Criteria......Page 296
6.8 SPECIFICATIONS AND IMPLEMENTATION OF EARTHING......Page 297
6.9 SAFETY AND SECURITY OF INSTALLATIONS......Page 298
6.10 ASSESSMENT OF SWITCHGEAR......Page 301
6.12 ARC FLASH HAZARDS......Page 303
6.12.3 Limits of Approach......Page 305
6.12.4 PPE Hazard Risk Categories......Page 307
6.12.5.1 IEEE Standard 1584 - 2002......Page 308
6.12.5.2 NFPA 70E - 2004......Page 311
6.12.5.3 Computer Software......Page 312
6.12.6 Selection of Calculation Method......Page 313
6.12.7.3 Reducing the Clearing Time......Page 314
6.12.7.4 Use of Arc Flash Detecting Relays......Page 315
PART III: POWER QUALITY......Page 317
7.1 OVERVIEW......Page 319
7.2 POWER QUALITY PROBLEMS......Page 320
7.2.1 Typical Power Quality Problems......Page 324
7.2.2 Case Studies......Page 326
7.3 COST OF POWER QUALITY......Page 327
7.3.2 QC......Page 328
7.3.3 Economic Profit......Page 329
7.3.4 A Case Study......Page 331
7.4 SOLUTIONS OF POWER QUALITY PROBLEMS......Page 333
7.4.1.1 SPDs......Page 334
7.4.1.2 BCKGs......Page 336
7.4.1.3 UPS......Page 337
7.4.1.5 ITR Operation......Page 339
7.5 SOLUTION CYCLE FOR POWER QUALITY PROBLEMS......Page 340
8.1.1 Voltage Drop......Page 343
8.1.2.1 Sources of Voltage Sag......Page 346
8.1.3 Flicker......Page 349
8.1.5.1 Impulse Transients......Page 350
8.2.1.2 Basic Theories (Case No. 1)......Page 352
8.2.1.4 Loss Reduction......Page 354
8.2.1.5 Illustrative Example......Page 355
8.2.1.6 Lateral Radial Feeder......Page 356
8.2.2 Adding New Lines......Page 359
8.2.3 Regulating the Voltage......Page 361
8.2.4 Applying Shunt Capacitors......Page 363
8.3.2 Magnitude of Voltage Sag......Page 369
8.3.3 Duration of Voltage Sag......Page 370
8.3.5 Illustrative Example......Page 371
8.4 ESTIMATION OF DISTRIBUTION LOSSES......Page 380
8.4.1 A Top - Down Approach......Page 381
9.1 BACKGROUND......Page 385
9.3 NEED FOR SHUNT COMPENSATION......Page 390
9.4 AN EXAMPLE......Page 394
9.5 HOW TO DETERMINE COMPENSATION......Page 395
10.1 WHAT ARE HARMONICS?......Page 405
10.2 SOURCES OF HARMONICS......Page 410
10.3 DISTURBANCES CAUSED BY HARMONICS......Page 419
10.3.1 Technical Problems......Page 421
10.4.2 rms Value......Page 423
10.4.4 Power and Harmonics......Page 424
10.5.2 THD......Page 425
10.5.3 Relation Between PF and THD......Page 426
10.6 STANDARDS AND RECOMMENDATIONS......Page 428
11.2.1 Supplying the Loads from Upstream......Page 431
11.2.3 Supplying the Loads from Different Sources......Page 432
11.3.3 Arrangement of System Earthing......Page 433
11.4.1 Passive Filters......Page 434
11.4.2 AFs......Page 435
11.4.3 Hybrid Filters......Page 436
11.6.1 General......Page 437
11.6.2 Need for Shunt Capacitors......Page 438
11.6.3 Effects of Harmonics on PF Capacitors......Page 439
11.6.4 PF Correction for a Pipe Welding Industry......Page 441
11.6.4.1 How the AF Works......Page 444
11.6.5 Crane Applications — Suez Canal Container Terminal ( SCCT )......Page 447
11.6.5.1 System Problems......Page 448
11.6.5.2 Solution......Page 452
11.6.6.3 System Description......Page 453
11.6.6.5 Point of Connection......Page 454
11.6.6.7 Protection......Page 455
11.6.6.8 Environmental Conditions......Page 456
PART IV: MANAGEMENT AND MONITORING......Page 457
12.1 OVERVIEW......Page 459
12.2 DSM......Page 461
12.3 NEEDS TO APPLY DSM......Page 462
12.4 MEANS OF DSM PROGRAMS......Page 463
12.5 INTERNATIONAL EXPERIENCE WITH DSM......Page 465
12.6 POTENTIAL FOR DSM APPLICATION......Page 466
12.6.2 Energy Consumption Savings......Page 467
12.7 THE DSM PLANNING PROCESS......Page 468
12.9 ENERGY EFFICIENCY......Page 473
12.12.1 Lighting......Page 474
12.12.2 Motors......Page 481
12.12.3 Heating......Page 484
12.12.4 Pumps......Page 486
12.12.4.1 Pump Characteristics......Page 487
12.12.4.2 Flow Rate Control......Page 489
12.12.4.3 An Illustrative Example......Page 491
13.1 INTRODUCTION......Page 493
13.2.2 Telemetry......Page 497
13.3.1 Instrumentation (First Component)......Page 498
13.3.3 Communication Networks (Third Component)......Page 499
13.4.1 Hardware......Page 502
13.4.2 Software......Page 504
13.5.1 Substation Automation......Page 509
13.5.3 Power Factor Correction System......Page 511
13.6.1 Smart Grid Overview......Page 514
13.6.2 Smart Grid Concept......Page 515
13.6.3 Driving Factors......Page 517
PART V: DISTRIBUTED GENERATION......Page 519
14.1 POWER SYSTEMS AND DISTRIBUTED GENERATION ( DG )......Page 521
14.2.1 Microturbines......Page 526
14.2.2 Wind Turbines......Page 529
14.2.3 Hydroelectric Pumped Storage Systems......Page 533
14.2.4 Photovoltaic ( PV ) Devices......Page 534
14.2.5 Asynchronous Generators......Page 538
14.2.6 Synchronous Generators......Page 540
14.3 CASE STUDY......Page 541
14.3.1 Distribution Generation Drivers......Page 543
14.3.2 Potential Benefits of DG on Increased Electric System Reliability......Page 544
14.3.2.1 Reliability Indices......Page 545
14.3.2.2 DG and Electric System Reliability......Page 548
14.3.3 Potential Benefits of DG in Reducing Peak Power Requirements......Page 550
14.3.3.1 Load Diversity and Congestion......Page 551
14.3.4 Potential Benefits of DG from Ancillary Services......Page 553
14.3.4.1 Potential Benefits of the Provision of Reactive Power or Volt - Ampere Reactive (Voltage Support)......Page 554
14.3.4.2 Simulated DG Reactive Power Effects......Page 556
14.3.4.3 Spinning Reserve, Supplemental Reserve, and Black Start......Page 557
14.3.5 Value of Power Quality Improvements......Page 558
14.3.6 Technical Specifications of DG and Utility Grid Interconnection......Page 559
14.3.7 Planning Process......Page 560
REFERENCES......Page 561
INDEX......Page 573