IEEE STD 80 2000
$25.35
IEEE Guide for Safety in AC Substation Grounding
Published By | Publication Date | Number of Pages |
IEEE | 2000 | 200 |
PDF Catalog
PDF Pages | PDF Title |
---|---|
1 | Title page Title page |
3 | Introduction Introduction Participants Participants |
5 | CONTENTS CONTENTS |
9 | 1. Overview 1. Overview 1.1 Scope 1.1 Scope 1.2 Purpose 1.2 Purpose |
10 | 1.3 Relation to other standards 1.3 Relation to other standards 2. References 2. References |
11 | 3. Definitions 3. Definitions |
16 | 4. Safety in grounding 4. Safety in grounding 4.1 Basic problem 4.1 Basic problem 4.2 Conditions of danger 4.2 Conditions of danger |
19 | 5. Range of tolerable current 5. Range of tolerable current 5.1 Effect of frequency 5.1 Effect of frequency 5.2 Effect of magnitude and duration 5.2 Effect of magnitude and duration |
20 | 5.3 Importance of high-speed fault clearing 5.3 Importance of high-speed fault clearing |
21 | 6. Tolerable body current limit 6. Tolerable body current limit 6.1 Duration formula 6.1 Duration formula 6.2 Alternative assumptions 6.2 Alternative assumptions |
22 | 6.3 Comparison of Dalziel’s equations and Biegelmeier’s curve 6.3 Comparison of Dalziel’s equations and Biegelmeier’s curve |
23 | 6.4 Note on reclosing 6.4 Note on reclosing |
24 | 7. Accidental ground circuit 7. Accidental ground circuit 7.1 Resistance of the human body 7.1 Resistance of the human body 7.2 Current paths through the body 7.2 Current paths through the body |
25 | 7.3 Accidental circuit equivalents 7.3 Accidental circuit equivalents |
28 | 7.4 Effect of a thin layer of surface material 7.4 Effect of a thin layer of surface material |
31 | 8. Criteria of tolerable voltage 8. Criteria of tolerable voltage 8.1 Definitions 8.1 Definitions |
34 | 8.2 Typical shock situations 8.2 Typical shock situations |
35 | 8.3 Step and touch voltage criteria 8.3 Step and touch voltage criteria |
36 | 8.4 Typical shock situations for gas-insulated substations 8.4 Typical shock situations for gas-insulated substations |
37 | 8.5 Effect of sustained ground currents 8.5 Effect of sustained ground currents 9. Principal design considerations 9. Principal design considerations 9.1 Definitions 9.1 Definitions |
38 | 9.2 General concept 9.2 General concept |
39 | 9.3 Primary and auxiliary ground electrodes 9.3 Primary and auxiliary ground electrodes 9.4 Basic aspects of grid design 9.4 Basic aspects of grid design 9.5 Design in difficult conditions 9.5 Design in difficult conditions |
40 | 9.6 Connections to grid 9.6 Connections to grid |
41 | 10. Special considerations for GIS 10. Special considerations for GIS 10.1 Definitions 10.1 Definitions |
42 | 10.2 GIS characteristics 10.2 GIS characteristics 10.3 Enclosures and circulating currents 10.3 Enclosures and circulating currents |
43 | 10.4 Grounding of enclosures 10.4 Grounding of enclosures 10.5 Cooperation between GIS manufacturer and user 10.5 Cooperation between GIS manufacturer and user |
44 | 10.6 Other special aspects of GIS grounding 10.6 Other special aspects of GIS grounding |
45 | 10.7 Notes on grounding of GIS foundations 10.7 Notes on grounding of GIS foundations 10.8 Touch voltage criteria for GIS 10.8 Touch voltage criteria for GIS |
46 | 10.9 Recommendations 10.9 Recommendations |
47 | 11. Selection of conductors and connections 11. Selection of conductors and connections 11.1 Basic requirements 11.1 Basic requirements |
48 | 11.2 Choice of material for conductors and related corrosion problems 11.2 Choice of material for conductors and related corrosion problems 11.2.1 Copper 11.2.1 Copper 11.2.2 Copper-clad steel 11.2.2 Copper-clad steel 11.2.3 Aluminum 11.2.3 Aluminum 11.2.4 Steel 11.2.4 Steel 11.2.5 Other considerations 11.2.5 Other considerations |
49 | 11.3 Conductor sizing factors 11.3 Conductor sizing factors 11.3.1 Symmetrical currents 11.3.1 Symmetrical currents |
53 | 11.3.2 Asymmetrical currents 11.3.2 Asymmetrical currents |
56 | 11.3.3 Additional conductor sizing factors 11.3.3 Additional conductor sizing factors |
57 | 11.4 Selection of connections 11.4 Selection of connections 12. Soil characteristics 12. Soil characteristics 12.1 Soil as a grounding medium 12.1 Soil as a grounding medium 12.2 Effect of voltage gradient 12.2 Effect of voltage gradient |
58 | 12.3 Effect of current magnitude 12.3 Effect of current magnitude 12.4 Effect of moisture, temperature, and chemical content 12.4 Effect of moisture, temperature, and chemical content |
59 | 12.5 Use of surface material layer 12.5 Use of surface material layer 13. Soil structure and selection of soil model 13. Soil structure and selection of soil model 13.1 Investigation of soil structure 13.1 Investigation of soil structure |
60 | 13.2 Classification of soils and range of resistivity 13.2 Classification of soils and range of resistivity 13.3 Resistivity measurements 13.3 Resistivity measurements |
63 | 13.4 Interpretation of soil resistivity measurements 13.4 Interpretation of soil resistivity measurements |
64 | 13.4.1 Uniform soil assumption 13.4.1 Uniform soil assumption |
65 | 13.4.2 Nonuniform soil assumptions 13.4.2 Nonuniform soil assumptions |
72 | 14. Evaluation of ground resistance 14. Evaluation of ground resistance 14.1 Usual requirements 14.1 Usual requirements 14.2 Simplified calculations 14.2 Simplified calculations |
73 | 14.3 Schwarz’s equations 14.3 Schwarz’s equations |
76 | 14.4 Note on ground resistance of primary electrodes 14.4 Note on ground resistance of primary electrodes 14.5 Soil treatment to lower resistivity 14.5 Soil treatment to lower resistivity 14.6 Concrete-encased electrodes 14.6 Concrete-encased electrodes |
80 | 15. Determination of maximum grid current 15. Determination of maximum grid current 15.1 Definitions 15.1 Definitions |
81 | 15.2 Procedure 15.2 Procedure |
82 | 15.3 Types of ground faults 15.3 Types of ground faults |
84 | 15.4 Effect of substation ground resistance 15.4 Effect of substation ground resistance 15.5 Effect of fault resistance 15.5 Effect of fault resistance 15.6 Effect of overhead ground wires and neutral conductors 15.6 Effect of overhead ground wires and neutral conductors |
85 | 15.7 Effect of direct buried pipes and cables 15.7 Effect of direct buried pipes and cables 15.8 Worst fault type and location 15.8 Worst fault type and location |
86 | 15.9 Computation of current division 15.9 Computation of current division |
91 | 15.10 Effect of asymmetry 15.10 Effect of asymmetry |
93 | 15.11 Effect of future changes 15.11 Effect of future changes |
94 | 16. Design of grounding system 16. Design of grounding system 16.1 Design criteria 16.1 Design criteria |
95 | 16.2 Critical parameters 16.2 Critical parameters 16.2.1 Maximum grid current (IG) 16.2.1 Maximum grid current (IG) 16.2.2 Fault duration (tf) and shock duration (ts) 16.2.2 Fault duration (tf) and shock duration (ts) 16.2.3 Soil resistivity (r) 16.2.3 Soil resistivity (r) 16.2.4 Resistivity of surface layer (rs) 16.2.4 Resistivity of surface layer (rs) |
96 | 16.2.5 Grid geometry 16.2.5 Grid geometry 16.3 Index of design parameters 16.3 Index of design parameters 16.4 Design procedure 16.4 Design procedure |
99 | 16.5 Calculation of maximum step and mesh voltages 16.5 Calculation of maximum step and mesh voltages 16.5.1 Mesh voltage (Em) 16.5.1 Mesh voltage (Em) |
102 | 16.5.2 Step voltage (Es) 16.5.2 Step voltage (Es) |
103 | 16.6 Refinement of preliminary design 16.6 Refinement of preliminary design 16.7 Application of equations for Em and Es 16.7 Application of equations for Em and Es 16.8 Use of computer analysis in grid design 16.8 Use of computer analysis in grid design |
104 | 17. Special areas of concern 17. Special areas of concern 17.1 Service areas 17.1 Service areas 17.2 Switch shaft and operating handle grounding 17.2 Switch shaft and operating handle grounding |
107 | 17.3 Grounding of substation fence 17.3 Grounding of substation fence |
115 | 17.4 Results of voltage profiles for fence grounding 17.4 Results of voltage profiles for fence grounding |
116 | 17.5 Control cable sheath grounding 17.5 Control cable sheath grounding 17.6 GIS bus extensions 17.6 GIS bus extensions 17.7 Surge arrester grounding 17.7 Surge arrester grounding 17.8 Separate grounds 17.8 Separate grounds |
117 | 17.9 Transferred potentials 17.9 Transferred potentials 17.9.1 Communication circuits 17.9.1 Communication circuits 17.9.2 Rails 17.9.2 Rails |
118 | 17.9.3 Low-voltage neutral wires 17.9.3 Low-voltage neutral wires 17.9.4 Portable equipment and tools supplied from substation 17.9.4 Portable equipment and tools supplied from substation 17.9.5 Piping 17.9.5 Piping 17.9.6 Auxiliary buildings 17.9.6 Auxiliary buildings |
119 | 17.9.7 Fences 17.9.7 Fences |
120 | 18. Construction of a grounding system 18. Construction of a grounding system 18.1 Ground grid construction—trench method 18.1 Ground grid construction—trench method 18.2 Ground grid construction—conductor plowing method 18.2 Ground grid construction—conductor plowing method |
121 | 18.3 Installation of connections, pigtails, and ground rods 18.3 Installation of connections, pigtails, and ground rods 18.4 Construction sequence consideration for ground grid installation 18.4 Construction sequence consideration for ground grid installation 18.5 Safety considerations during subsequent excavations 18.5 Safety considerations during subsequent excavations 19. Field measurements of a constructed grounding system 19. Field measurements of a constructed grounding system 19.1 Measurements of grounding system impedance 19.1 Measurements of grounding system impedance |
122 | 19.1.1 Two-point method 19.1.1 Two-point method 19.1.2 Three-point method 19.1.2 Three-point method 19.1.3 Ratio method 19.1.3 Ratio method 19.1.4 Staged-fault tests 19.1.4 Staged-fault tests |
123 | 19.1.5 Fall-of-potential method 19.1.5 Fall-of-potential method |
124 | 19.2 Field survey of potential contours and touch and step voltages 19.2 Field survey of potential contours and touch and step voltages |
125 | 19.3 Assessment of field measurements for safe design 19.3 Assessment of field measurements for safe design 19.4 Ground grid integrity test 19.4 Ground grid integrity test |
126 | 19.5 Periodic checks of installed grounding system 19.5 Periodic checks of installed grounding system 20. Physical scale models 20. Physical scale models |
127 | Annex A—Bibliography Annex A—Bibliography |
137 | Annex B—Sample calculations Annex B—Sample calculations |
153 | Annex C—Graphical and approximate analysis of current division Annex C—Graphical and approximate analysis of current division |
172 | Annex D—Simplified step and mesh equations Annex D—Simplified step and mesh equations |
175 | Annex E—Equivalent uniform soil model for nonuniform soils Annex E—Equivalent uniform soil model for nonuniform soils |
178 | Annex F—Parametric analysis of grounding systems Annex F—Parametric analysis of grounding systems |
193 | Annex G—Grounding methods for high-voltage stations with grounded neutrals Annex G—Grounding methods for high-voltage stations with grounded neutrals |