Grounds for Grounding

GROUNDS FOR GROUNDING

Gain a comprehensive understanding of all aspects of grounding theory and application in this new, expanded edition

Grounding design and installation are crucial to ensure the safety and performance of any electrical or electronic system irrespective of size. Successful grounding design requires a thorough familiarity with theory combined with practical experience with real-world systems. Rarely taught in schools due to its complexity, identifying and implementing the appropriate solution to grounding problems is nevertheless a vital skill in the industrial world for any electrical engineer.

In Grounds for Grounding, readers will discover a complete and thorough approach to the topic that blends theory and practice to demonstrate that a few rules apply to many applications. The book provides basic concepts of Electromagnetic Compatibility (EMC) that act as the foundation for understanding grounding theory and its applications. Each avenue of grounding is covered in its own chapter, topics from safety aspects in facilities, lightning, and NEMP to printed circuit board, cable shields, and enclosure grounding, and more.

Grounds for Grounding readers will also find:

• Revised and updated information presented in every chapter
• New chapters on grounding for generators, uninterruptible power sources (UPSs)
• New appendices including a grounding design checklist, grounding documentation content, and grounding verification procedures

Grounds for Grounding is a useful reference for engineers in circuit design, equipment, and systems, as well as power engineers, platform, and facility designers.

Auteur

Elya B. Joffe is President of Elya Joffe - Electromagnetic Solutions, Ltd. He holds a B.ScEE from Ben Gurion University, Israel, and is a Registered Professional Engineer. Elya is an IEEE Life Senior Member, and Past President of the IEEE EMC and Product Safety Engineering Societies. Elya has received many awards from the IEEE and EMC Society, particularly the prestigious IEEE EMC Society 2002 Laurence G. Cumming Award for Outstanding Service and the 2006 IEEE RAB Larry K. Wilson Transnational Award. He is an iNARTE-certified EMC and ESD Control Engineer, and is a Member of IEEE-HKN and dB Society. Kai-Sang Lock, PhD, is a Professor of Engineering at the Singapore Institute of Technology. He has been a practicing Professional Engineer for over 20 years. He is a Fellow of the Academy of Engineering Singapore, a Fellow of the Institution of Engineering and Technology, UK, an Honorary Fellow of the Institution of Engineers, Singapore, as well as a Life Senior Member of IEEE. He was a President of the Institution of Engineers, Singapore, a past Board Member of the Professional Engineers Board, and a past Chairman of the Singapore Standards Council.

Texte du rabat

GROUNDS FOR GROUNDING Gain a comprehensive understanding of all aspects of grounding theory and application in this new, expanded edition Grounding design and installation are crucial to ensure the safety and performance of any electrical or electronic system irrespective of size. Successful grounding design requires a thorough familiarity with theory combined with practical experience with real-world systems. Rarely taught in schools due to its complexity, identifying and implementing the appropriate solution to grounding problems is nevertheless a vital skill in the industrial world for any electrical engineer. In Grounds for Grounding, readers will discover a complete and thorough approach to the topic that blends theory and practice to demonstrate that a few rules apply to many applications. The book provides basic concepts of Electromagnetic Compatibility (EMC) that act as the foundation for understanding grounding theory and its applications. Each avenue of grounding is covered in its own chapter, topics from safety aspects in facilities, lightning, and NEMP to printed circuit board, cable shields, and enclosure grounding, and more. Grounds for Grounding readers will also find: Revised and updated information presented in every chapter New chapters on grounding for generators, uninterruptible power sources (UPSs) * New appendices including a grounding design checklist, grounding documentation content, and grounding verification procedures Grounds for Grounding is a useful reference for engineers in circuit design, equipment, and systems, as well as power engineers, platform, and facility designers.

Contenu

Preface to the Second Edition ix

Preface to First Edition xi

About the Companion Website xiii

1 What is Density Functional Theory? 1

1.1 How to Approach This Book 1

1.2 Examples of DFT in Action 2

1.2.1 Ammonia Synthesis by Heterogeneous Catalysis 2

1.2.2 Embrittlement of Metals by Trace Impurities 3

1.2.3 Materials Properties for Modeling Planetary Formation 4

1.2.4 Screening Large Collections of Materials to Develop Photoanodes 5

1.3 The Schrödinger Equation 7

1.4 Density Functional Theory - From Wavefunctions to Electron Density 9

1.5 The Exchange-Correlation Functional 12

1.6 The Quantum Chemistry Tourist 13

1.6.1 Localized and Spatially Extended Functions 13

1.6.2 Wavefunction-Based Methods 15

1.6.3 The Hartree-Fock Method 15

1.6.4 Beyond Hartree-Fock 18

1.7 What Can DFT Not Do? 22

1.8 Density Functional Theory in Other Fields 23

1.9 How to Approach This Book (Revisited) 24

1.10 Which Code Should I Use? 25

Further Reading 26

References 27

2 DFT Calculations for Simple Solids 29

2.1 Periodic Structures, Supercells, and Lattice Parameters 29

2.2 Face-Centered Cubic Materials 31

2.3 Hexagonal Close-Packed Materials 32

2.4 Crystal Structure Prediction 35

2.5 Phase Transformations 35

Exercises 37

Further Reading 37

Appendix - Calculation Details 38

Reference 38

3 Nuts and Bolts of DFT Calculations 39

3.1 Reciprocal Space and k-Points 40

3.1.1 Plane Waves and the Brillouin Zone 40

3.1.2 Integrals in k-Space 42

3.1.3 Choosing k-Points in the Brillouin Zone 43

3.1.4 Metals - Special Cases in k-Space 47

3.1.5 Summary of k-Space 48

3.2 Energy Cutoffs 49

3.2.1 Pseudopotentials 50

3.3 Numerical Optimization 51

3.3.1 Optimization in One Dimension 52

3.3.2 Optimization in More Than One Dimension 54

3.3.3 What Do I Really Need to Know About Optimization? 57

3.4 DFT Total Energies - An Iterative Optimization Problem 58

3.5 Geometry Optimization 59

3.5.1 Internal Degrees of Freedom 59

3.5.2 Geometry Optimization with Constrained Atoms 61

3.5.3 Optimizing Supercell Volume and Shape 61

Exercises 62

Further Reading 63

Appendix - Calculation Details 64

References 64

4 Accuracy of DFT Calculations 65

4.1 How Accurate are DFT Calculations? 65

4.2 Choosing a Functional 69

4.3 Examples of Physical Accuracy 73

4.3.1 Benchmark Calculations for Molecular Systems - Energy and Geometry 74

4.3.2 Benchmark Calculations for Molecular Systems - Vibrational Frequencies 75

4.3.3 Crystal Structures and Cohesive Energies 75

4.3.4 Adsorption Energies and Bond Strengths 76

4.4 When Might DFT Fail? 77

Exercises 78

Further Reading 79

References 79

5 DFT Calculations for Surfaces of Solids 81

5.1 Why Surfaces are Important 81

5.2 Periodic Boundary Conditions and Slab Models 82

5.3 Choosing k-Points for Surface Calculations 85

5.4 Classification of Surfaces by Miller Indices 85

5.5 Surface Relaxation 88

5.6 Calculation of Surface Energies 91

5.7 Symmetric and Asymmetric Slab Models 92

5.8 Surface Reconstruction 93

5.9 Adsorbates on Surfaces 95

5.9.1 Accuracy of Adsorption Energies 98

5.10 Effects of Surface Coverage 99

5.11 DFT Calculations for Grain Boundaries 101

Exercises 102

Further Reading 103

Appendix - Calculation Details 104…