Understandable Electric Circuits: Key Concepts

Cover......Page 1
Acknowledgments......Page 6
About the author......Page 16
R.1.1 SI units and circuit quantities......Page 22
R.1.2 Metric prefixes (SI prefixes)......Page 23
R.1.3 Metric conversion......Page 24
R.1.4 The unit factor method......Page 25
R.2.1 Write in scientific notation......Page 27
R.3.1 Write in engineering notation......Page 29
Summary......Page 31
Self-test......Page 33
1.1.1 Why study electric circuits?......Page 36
1.1.2 Careers in electrical, electronic, and computer engineering......Page 37
1.1.3 Milestones of electric circuit theory......Page 38
1.2.1 Basic electric circuits......Page 39
1.2.2 Circuit schematics (diagrams) and symbols......Page 41
1.3.1 Current......Page 42
1.3.2 1-ampere current......Page 43
1.3.3 The direction of electric current......Page 44
1.4.1 Voltage/electromotive force......Page 45
1.4.2 Potential difference/voltage......Page 46
1.5.1 Resistance/resistor......Page 48
1.5.2 Factors affecting resistance......Page 49
1.5.3 Conductance......Page 52
1.5.4 Ohm's law......Page 53
1.5.5 I–V characteristics of Ohm's law......Page 55
1.6.1 Reference direction of current......Page 56
1.6.2 Reference polarity of voltage......Page 57
1.6.3 Mutually related reference polarity of current/voltage......Page 58
Summary......Page 59
Practice problems......Page 61
2.1.1 Work......Page 64
2.1.2 Energy......Page 65
2.1.4 Electric power......Page 67
2.1.5 The reference direction of power......Page 69
2.2.1 Closed-loop circuit......Page 71
2.2.2 Kirchhoff's voltage law (KVL) # 1......Page 72
2.2.3 Kirchhoff's voltage law (KVL) # 2......Page 73
2.2.4 Experimental circuit of KVL......Page 74
2.2.5 KVL extension......Page 75
2.3.1 Kirchhoff's current law (KCL) # 1......Page 76
2.3.2 Kirchhoff's current law (KCL) # 2......Page 77
2.3.3 Physical property of KCL......Page 79
2.3.4 Procedure to solve a complicated problem......Page 80
2.3.5 Supernode......Page 81
2.3.6 Some important circuit terminologies......Page 83
2.4.1 Ideal voltage source......Page 84
2.4.2 Real voltage source......Page 85
2.4.3 Ideal current source......Page 87
2.4.4 Real current source......Page 89
Summary......Page 90
Practice problems......Page 91
3 Series–parallel resistive circuits......Page 96
3.1.1 Series resistive circuits......Page 97
3.1.3 Series current and power......Page 98
3.1.4 An example of a series circuit......Page 99
3.1.5 Voltage divider rule (VDR)......Page 100
3.1.7 Voltage subscript notation......Page 102
3.2.1 Parallel resistive circuits......Page 103
3.2.2 Parallel voltage and current......Page 104
3.2.3 Parallel resistance and power......Page 105
3.2.4 An example of a parallel circuit......Page 106
3.2.5 Current divider rule (CDR)......Page 107
3.3.2 Analysis of the series–parallel circuits......Page 109
3.3.3 Currents and voltages of a series–parallel circuit......Page 111
3.4.1 Wye and delta configurations......Page 112
3.4.2 Tee (T) and pi (π) configurations......Page 113
3.4.3 Delta to wye conversion (Δ→Y)......Page 114
3.4.4 Wye to delta conversion (Y→Δ), RY, and RD......Page 115
3.4.5 An example of wye and delta conversion......Page 116
3.4.6 Using Δ →Y conversion to simplify bridge circuits......Page 117
3.4.7 Balanced bridge......Page 118
3.4.8 Measure unknown resistors using the balanced bridge......Page 119
Summary......Page 120
Practice problems......Page 122
4.1.1 Source equivalent conversion......Page 130
4.1.3 Source conversion examples......Page 132
4.1.4 Voltage sources in series......Page 134
4.1.5 Voltage sources in parallel......Page 135
4.1.7 Current sources in series......Page 136
4.2.1 Branch current analysis......Page 137
4.2.2 Procedure for applying the branch current analysis......Page 138
4.2.3 Branch current analysis examples......Page 139
4.3.1 Mesh current analysis......Page 142
4.3.3 Mesh current analysis examples......Page 143
4.4.1 Procedure for applying the node voltage analysis......Page 146
4.4.2 Node voltage analysis examples......Page 147
Summary......Page 151
Practice problems......Page 153
Introduction to the network theorems......Page 158
5.1.1 Steps to apply the superposition theorem......Page 159
5.1.2 Superposition examples......Page 160
5.2.2 Thevenin and Norton equivalent circuits......Page 164
5.2.3 Equivalent resistance and voltage/current......Page 165
5.2.4 Procedure for applying the Thevenin's and Norton's theorems......Page 166
5.2.5 Thevenin/Norton equivalent example......Page 167
5.2.6 Viewpoints of Thevenin's and Norton's equivalent circuits......Page 169
5.2.7 Norton's theorem examples......Page 174
5.3.1 Maximum power transfer theorem......Page 178
5.3.2 Applications of maximum power transfer......Page 179
5.3.3 Proof of maximum power transfer theorem......Page 180
5.4.1 Millman's theorem......Page 181
5.4.2 Millman's theorem example......Page 183
5.4.3 Substitution theorem......Page 184
5.4.4 Substitution theorem example......Page 185
Summary......Page 186
Practice problems......Page 188
6 Capacitors and inductors......Page 192
6.1.2 Capacitors......Page 193
6.1.3 Charging a capacitor......Page 194
6.1.5 Discharging a capacitor......Page 196
6.1.6 Capacitance......Page 197
6.1.7 Calculating capacitance......Page 198
6.1.8 Factors affecting capacitance......Page 199
6.1.10 Relationship between the v and i of a capacitor......Page 201
6.1.11 Ohm's law for a capacitor......Page 202
6.1.12 Energy stored by a capacitor......Page 203
6.2.1 Total or equivalent capacitance......Page 204
6.2.2 Capacitors in series......Page 206
6.2.3 Capacitors in parallel......Page 207
6.2.4 Physical properties of parallel Ceq......Page 208
6.2.5 Capacitors in series–parallel......Page 209
6.3.1 Electromagnetic induction......Page 210
6.3.2 Faraday's law......Page 211
6.3.3 Lenz's law......Page 212
6.3.5 Self-inductance......Page 213
6.3.6 Ohm's law for an inductor......Page 214
6.3.7 Factors affecting inductance......Page 215
6.3.8 Energy stored in an inductor......Page 216
6.3.9 Calculating the energy stored in an inductor......Page 217
6.3.10 Winding resistor of an inductor......Page 218
6.4.1 Series and parallel inductors......Page 219
6.4.2 Inductors in series–parallel......Page 221
Summary......Page 222
Practice problems......Page 223
7 Transient analysis of circuits......Page 226
7.1.2 Transient and steady state......Page 227
7.1.3 Step response......Page 228
7.1.4 Source-free and unit-step response......Page 229
7.1.5 The initial condition of the dynamic circuit......Page 230
7.2.1 The charging process of an RC circuit......Page 231
7.2.2 Quantity analysis of the RC charging process......Page 233
7.2.3 Charging equations for an RC circuit......Page 234
7.2.4 Example with RC circuit......Page 235
7.3.1 The discharging process of the RC circuit......Page 236
7.3.2 Quantity analysis of the RC discharging process......Page 237
7.3.3 RC time constant......Page 239
7.3.4 The RC time constant and charging/discharging......Page 240
7.3.5 Different time constants for charging/discharging......Page 241
7.3.6 Discharging process examples......Page 242
7.4.1 RL circuit......Page 243
7.4.2 Energy-storing process of the RL circuit......Page 244
7.4.3 Quantity analysis of the RL energy-storing process......Page 245
7.5.1 Energy-releasing process of an RL circuit......Page 247
7.5.2 Quantity analysis of the RL energy-releasing process......Page 248
7.5.3 RL time constant......Page 250
7.5.4 RL time constant and energy storing/releasing......Page 251
Summary......Page 252
Practice problems......Page 254
8.1.1 Magnetism......Page 258
8.1.3 Domain theory of magnetism......Page 260
8.2.1 Charging and electric field......Page 261
8.2.2 Electromagnetism......Page 263
8.3.1 Permeability and reluctance......Page 264
8.4.1 Magnetic field intensity......Page 267
8.4.2 Magnetic hysteresis......Page 268
Summary......Page 270
Practice problems......Page 274
9 Fundamentals of AC circuits......Page 276
9.1.2 DC waveforms......Page 277
9.1.3 AC waveforms......Page 278
9.1.4 Period and frequency......Page 279
9.1.6 The phase of a sine function......Page 281
9.1.7 An example of a sine voltage......Page 282
9.1.8 Phase difference of the sine function......Page 283
9.1.9 An example of phase difference......Page 285
9.2.1 Peak value and peak–peak value......Page 286
9.2.2 Average value......Page 287
9.2.3 Instantaneous value......Page 288
9.2.5 Quantitative analysis of RMS value......Page 289
9.2.6 RMS value of a periodical function......Page 290
9.3.1 Introduction to phasor notation......Page 291
9.3.2 Complex numbers review......Page 292
9.3.3 Phasor domain......Page 294
9.3.4 Phasor diagram......Page 295
9.3.5 Rotating factor......Page 296
9.3.6 Differentiation and integration of the phasor......Page 298
9.3.7 Examples of phasor domain......Page 299
9.4.1 Resistor's AC response......Page 300
9.4.2 Resistor's AC response in time domain......Page 301
9.4.3 Resistor's AC response in phasor domain......Page 302
9.4.4 Inductor's AC response......Page 303
9.4.5 The current and voltage in an inductive circuit......Page 304
9.4.6 Characteristics of an inductor......Page 305
9.4.7 Inductor's AC response in phasor domain......Page 306
9.4.8 Capacitor's AC response......Page 307
9.4.9 The current and voltage in a capacitive circuit......Page 308
9.4.11 Capacitor's AC response in phasor domain......Page 309
Summary......Page 311
Practice problems......Page 314
10 Methods of AC circuit analysis......Page 316
10.1.2 Admittance......Page 317
10.1.3 Characteristics of the impedance......Page 318
10.1.4 Impedance examples......Page 320
10.1.5 Characteristics of the admittance......Page 321
10.1.6 Admittance examples......Page 323
10.2.1 Equivalent impedance......Page 324
10.2.2 The phasor forms of KVL, KCL, VDR, and CDR......Page 325
10.2.3 Equivalent impedance examples......Page 326
10.3.1 Instantaneous power......Page 328
10.3.2 The waveform of instantaneous power......Page 329
10.3.3 Instantaneous power for a resistive component......Page 330
10.3.4 Instantaneous power for inductive/capacitive components......Page 331
10.3.6 Active power and φ......Page 332
10.3.7 Reactive power......Page 333
10.3.8 Apparent power......Page 335
10.3.9 Power triangle......Page 336
10.3.11 Power in AC circuits......Page 337
10.3.12 Power factor......Page 338
10.3.13 Power factor correction......Page 339
10.3.14 Total power......Page 340
10.3.15 Power factor examples......Page 341
10.4.1 Mesh current analysis......Page 345
10.4.2 Mesh current analysis example......Page 346
10.4.4 Node voltage analysis example......Page 347
10.4.5 Superposition theorem......Page 348
10.4.7 Thevenin's and Norton's theorems — an example......Page 350
Summary......Page 353
Practice problems......Page 356
11.1.1 Introduction to series resonance......Page 360
11.1.2 Frequency and impedance of series resonance......Page 361
11.1.3 Current and phasor diagram of series resonance......Page 362
11.1.4 Response curves of XL, XC, and Z versus f......Page 364
11.1.5 Phase response of series resonance......Page 365
11.1.6 Quality factor......Page 366
11.1.7 Voltage of series resonance......Page 367
11.2.1 The bandwidth of series resonance......Page 368
11.2.2 The selectivity of series resonance......Page 369
11.2.3 The quality factor and selectivity......Page 370
11.3.1 Introduction to parallel resonance......Page 373
11.3.2 Frequency and admittance of parallel resonance......Page 374
11.3.3 Current of parallel resonance......Page 375
11.3.4 Phasor diagram of parallel resonance......Page 376
11.3.6 Current of parallel resonance......Page 377
11.3.7 The bandwidth of parallel resonance......Page 378
11.4.1 Resonant admittance......Page 379
11.4.2 Resonant frequency......Page 380
11.4.3 Applications of the resonance......Page 381
Summary......Page 382
Practice problems......Page 384
12.1.1 Mutual inductance and self-inductance......Page 386
12.1.2 Factors affecting mutual inductance......Page 387
12.1.3 Coefficient of coupling......Page 388
12.2.1 Transformer......Page 389
12.2.2 Air-core transformer......Page 390
12.2.3 Iron-core transformer......Page 391
12.2.4 Ideal transformer......Page 392
12.2.5 Transformer parameters conversion......Page 394
12.3.1 Step-up transformer......Page 395
12.3.2 Step-down transformer......Page 396
12.3.3 Applications of step-up and step-down transformers......Page 397
12.3.4 Other types of transformers......Page 398
12.4.1 Maximum power transfer......Page 399
12.4.2 Impedance matching......Page 400
Summary......Page 401
Practice problems......Page 403
13.1.1 Introduction to dependent sources......Page 406
13.1.2 Types of dependent sources......Page 407
13.1.3 Circuits with dependent sources......Page 408
13.1.5 Examples of equivalent conversion......Page 409
13.2.1 KVL and KCL......Page 410
13.2.2 Node voltage analysis......Page 412
13.2.3 Mesh current analysis......Page 413
13.2.4 Superposition theorem......Page 414
13.2.5 Thevenin's theorem......Page 415
Practice problems......Page 416
14.1.1 Introduction to three-phase systems......Page 420
14.1.2 Two connection methods......Page 421
14.2.1 Wye-connected voltage sources......Page 422
14.2.2 Delta-connected sources......Page 424
14.3.1 Y–Y system......Page 426
14.3.2 Y–Δ system......Page 427
14.4.1 Power in balanced Y-or Δ-connected systems......Page 428
14.4.2 Three-phase power examples......Page 430
Summary......Page 431
Practice problems......Page 433
Appendix A Greek alphabets......Page 436
Appendix B Differentiation of the phasor......Page 438
Answers to selected odd-numbered problems......Page 440
Index......Page 446
Back Cover......Page 454