Electrical Power and Controls

by Skvarenina, Timothy L.; Dewitt, William E.

• ISBN13: 9780130801821
• ISBN10: 0130801828
• Edition: 1st
• Format: Paperback
• Copyright: 2000-05-24
• Publisher: Pearson College Div

Summary

For one-semester, sophomore-level, courses in Electrical Power and/or Controls, or Machines and/or Transformers in an EET program.Broad in scope, yet deep in content, this text offers unique, single-volume coverage of machines, transformers, controls, and electrical power distribution. The focus throughout is on topics that engineers and technologists today and in the future will encounter in the workplace e.g., the principles of operation and application of motors, motor controls, power quality, power electronics, motor circuit design, programmable logic controllers, etc. The text includes much more material than could be covered in a single semester allowing a great deal of flexibility in course design.

Table of Contents

Fundamentals of Energy and The Power System	1	(26)
Introduction	1	(1)
Objectives	1	(1)
Gravitational Force	1	(1)
Energy	2	(6)
Thermodynamic Considerations	8	(1)
Power	8	(1)
Torque	9	(1)
The Power System	10	(6)
The National Power Grid	16	(2)
Changing Times for the Electric Utilities	18	(5)
Summary	23	(1)
Questions	24	(1)
Problems	24	(2)
Single- and Three-Phase Power	26	(16)
Introduction	26	(1)
Objectives	26	(1)
DC Circuits	26	(1)
Single-Phase AC Circuits	27	(4)
Three-Phase AC Circuits	31	(4)
Power Factor Correction	35	(4)
Summary	39	(1)
Questions	39	(1)
Problems	40	(2)
Power Quality Considerations	42	(35)
Introduction	42	(1)
Objectives	42	(1)
Disturbances	43	(8)
What Are Harmonics?	51	(7)
Why Worry About Harmonic Currents?	58	(11)
Notching	69	(1)
IEEE Standard 519	70	(1)
Troubleshooting Power Quality Problems	71	(3)
Summary	74	(1)
Questions	75	(1)
Problems	76	(1)
Magnetic Materials and Circuits	77	(16)
Introduction	77	(1)
Objectives	78	(1)
Magnetic Fields	78	(6)
Properties of Magnetic Materials	84	(2)
Electrical Circuit Analogy	86	(2)
Hysteresis	88	(1)
Magnetic Core Losses	89	(2)
Summary	91	(1)
Problems	91	(2)
Transformers	93	(43)
Introduction	93	(1)
Objectives	93	(1)
Transformer Nameplate Data	93	(1)
Transformer Construction	94	(5)
Ideal Transformer Operation	99	(3)
Exciting Current	102	(4)
Transformer Equivalent Circuits	106	(5)
Determining Circuit Parameters	111	(3)
Transformer Efficiency	114	(1)
Transformer Frequency Response	115	(2)
Voltage Regulation	117	(3)
K-Factor-Rated Transformers	120	(1)
Autotransformers	121	(2)
Instrument Transformers	123	(2)
Three-Phase Transformers	125	(6)
Summary	131	(2)
Questions	133	(1)
Problems	134	(2)
Introduction to Motors and Generators	136	(30)
Objectives	137	(1)
Five Electromagnetic Principles	137	(5)
A Simple AC Machine	142	(4)
A Practical AC Synchronous Machine	146	(8)
A Simple DC Machine	154	(3)
A Practical DC Machine	157	(3)
Efficiency and Losses	160	(2)
Heating, Cooling, and Lifetime of Machines	162	(2)
Summary	164	(1)
Questions	165	(1)
Problems	165	(1)
Three-Phase Induction Motors	166	(47)
Introduction	166	(1)
Objectives	166	(1)
Construction Features	167	(3)
Nameplate Data	170	(4)
Principles of Operation	174	(3)
Induction Motor Equivalent Circuit	177	(5)
Torque--Speed Characteristic	182	(3)
Determination of Equivalent Circuit Parameters	185	(1)
Induction Motor Performance	186	(2)
NEMA Motor Designs	188	(6)
Induction Motor Efficiency	194	(2)
Energy-Efficient Motor	196	(5)
Types of Load Torques	201	(1)
Motor Application Information	202	(5)
Wiring Connections for Induction Motors	207	(1)
Starting Considerations for Induction Motor	208	(2)
Summary	210	(1)
Questions	211	(1)
Problems	211	(2)
Single-Phase Motors	213	(11)
Introduction	213	(1)
Objectives	213	(1)
Principles of Operation of a Single-Phase Motor	213	(3)
Types of Single-Phase Motors	216	(7)
Troubleshooting	223	(1)
Questions	223	(1)
Problems	223	(1)
Power Electronics	224	(35)
Introduction	224	(1)
Objectives	224	(1)
Power Electronic Switching Devices	225	(7)
Adjustable-Speed Drives	232	(1)
Adjustable-Speed Induction Motor Drives	233	(9)
Motor Performance Under Variable-Frequency Operation	242	(4)
Operation of an Adjustable-Speed Drive (ASD)	246	(3)
Selecting a Motor for Variable-Frequency Operation	249	(1)
Brushless DC and Stepper Motors	250	(7)
Summary	257	(1)
Questions	258	(1)
Problems	258	(1)
The Synchronous Machine	259	(45)
Introduction	259	(1)
Objectives	259	(1)
Synchronous Machine Construction	260	(4)
Principles of Operation	264	(3)
Steady-State Equivalent Circuit for a Round-Rotor Synchronous Machine	267	(4)
Performance and Analysis of Synchronous Generators	271	(19)
Synchronous Motor	290	(7)
Power Factor Improvement with a Synchronous Machine	297	(1)
Efficiency and Losses in the Synchronous Machine	298	(2)
Summary	300	(1)
Questions	301	(1)
Problems	301	(3)
DC Machines	304	(44)
Introduction	304	(1)
Objectives	304	(1)
Construction and Operating Principles of the DC Machine	305	(12)
DC Generators	317	(12)
DC Motors	329	(11)
Losses and Efficiency	340	(4)
Summary	344	(2)
Questions	346	(1)
Problems	346	(2)
Control Devices and Circuits	348	(26)
Introduction	348	(1)
Objectives	348	(1)
Relays, Contactors, and Motor Starters	348	(8)
Pilot Devices	356	(3)
Control Methods and Ladder Diagrams	359	(6)
Reduced-Voltage AC Motor Starters	365	(3)
Reversible Starters	368	(1)
Starting DC Motor	369	(3)
Troubleshooting	372	(1)
Questions	372	(1)
Problems	373	(1)
Building Electrical Systems	374	(20)
Introduction	374	(1)
Objectives	374	(1)
Building Design	374	(2)
Electrical Conductors	376	(2)
The National Electrical Code (NEC)	378	(2)
Voltage Drop	380	(1)
Motor Circuits	381	(4)
Motor Circuit Design	385	(3)
Residential Electrical Systems	388	(3)
Summary	391	(1)
Questions	392	(1)
Problems	392	(2)
Programmable Logic Controllers (PLCs)	394	(43)
Introduction	394	(1)
Objectives	394	(1)
PLC Overview	395	(5)
Arithmetic Conversions	400	(3)
PLC Components	403	(9)
PLC Programming	412	(18)
Communications	430	(4)
Summary	434	(1)
Questions	434	(1)
Problems	435	(2)
Appendix A: NEC Tables	437	(12)
Appendix B: List of Symbols	449	(6)
Index	455