IEC TS 63042-202:2021

UHV AC transmission systems - Part 202: UHV AC transmission line design

IEC TS 63042-202:2021(E) provides common rules for the design of overhead transmission lines with the highest voltages of AC transmission systems exceeding 800 kV, so as to provide safety and proper functioning for the intended use.
This technical specification aims to give the main principles for the design of UHV AC overhead transmission lines, mainly including selection of clearance, insulation coordination and insulator strings design, bundle-conductor selection, earth wire/optical ground wires selection, tower and foundation design, environmental consideration. The design criteria apply to new construction, reconstruction and expansion of UHV AC overhead transmission line.

General Information

• Status: Published
• Publication Date: 12-Oct-2021
• ICS: 29.240.20 - Power transmission and distribution lines
• Technical Committee: TC 122 - UHV AC transmission systems
• Drafting Committee: WG 2 - TC 122/WG 2
• Current Stage: PPUB - Publication issued
• Start Date: 09-Nov-2021
• Completion Date: 13-Oct-2021

Standards Content (Sample)

IEC TS 63042-202 ®
Edition 1.0 2021-10
TECHNICAL
SPECIFICATION
colour
inside
UHV AC transmission systems –
Part 202: UHV AC Transmission line design
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IEC TS 63042-202 ®
Edition 1.0 2021-10
TECHNICAL
SPECIFICATION
colour
inside
UHV AC transmission systems –
Part 202: UHV AC Transmission line design

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.20 ISBN 978-2-8322-1035-7

– 2 – IEC TS 63042-202:2021 © IEC 2021
CONTENTS
FOREWORD . 10
1 Scope . 12
2 Normative references . 12
3 Terms and definitions . 13
4 Symbols and abbreviations . 13
5 UHV AC transmission line requirements . 14
5.1 General requirements . 14
5.2 Reliability requirements. 14
5.3 Electrical requirements . 14
5.4 Security requirements . 14
5.5 Safety requirements . 14
5.6 Environmental impact. 14
5.7 Economy . 14
6 Selection of clearance . 15
6.1 General . 15
6.2 Air gap, tower clearances (strike distance) . 15
6.2.1 Power frequency voltage . 15
6.2.2 Switching overvoltage . 15
6.2.3 Lightning overvoltage . 15
6.3 Phase to phase spacing (Horizontal, Vertical) . 16
6.4 Ground clearances – Statutory requirements, electric and magnetic field
limits . 16
6.5 Conductor-earth wire spacing, shielding angle – Lightning performance
criteria . 16
7 Insulation coordination, insulator and insulator string design . 17
7.1 General . 17
7.2 Insulation requirements – electrical design considerations . 17
7.3 Insulating materials, type of insulators . 17
7.4 Insulator string configurations for disc type insulators . 18
7.5 Mechanical design criteria of insulator strings and associated hardware
fittings . 19
8 Bundle-conductor selection . 19
8.1 General . 19
8.2 Conductor types . 19
8.3 Bundle conductor configurations . 20
8.3.1 Number of sub-conductors . 20
8.3.2 Bundle spacing . 20
8.4 Conductor bundle selection process . 20
8.4.1 Cross-section of conductor . 20
8.4.2 Conductor ampacity . 20
8.4.3 Requirements for electromagnetic environment . 21
8.4.4 Capital cost and loss evaluation . 21
8.5 Mechanical strength . 21
8.6 Conductor accessories . 22
8.6.1 General requirements for fittings . 22
8.6.2 Type and design features of link fittings, vibration dampers, spacers . 22
9 Earth wire/OPGW selection . 23

9.1 General . 23
9.2 Type of earth wire/OPGW . 23
9.3 Design Criteria/Requirements Specific to UHV Lines. 23
9.4 Induced voltages on earth wire . 23
10 Tower and foundation design . 24
10.1 General . 24
10.2 Tower classification . 24
10.2.1 General . 24
10.2.2 Conductor configuration . 24
10.2.3 Constructional features . 29
10.2.4 Line deviation angle . 29
10.2.5 Tower extensions . 30
10.2.6 Specific requirements . 30
10.3 Tower design . 30
10.3.1 General . 30
10.3.2 Selection of tower geometry based on electrical clearances . 30
10.3.3 Calculation of loads on tower . 31
10.3.4 Analysis using software . 31
10.3.5 Full scale tower testing . 32
10.3.6 Tower design methodology . 32
10.4 Foundation design . 33
10.4.1 General . 33
10.4.2 Open cast type foundations . 34
10.4.3 Raft type foundations . 34
10.4.4 Deep foundations (Pile/Well/Pier/Steel Anchor type) . 35
11 Environmental considerations . 35
11.1 General . 35
11.2 Electric field . 35
11.2.1 General . 35
11.2.2 Reference level of electric field . 35
11.2.3 Prediction of electric field . 36
11.2.4 Mitigation measures of electric field . 36
11.3 Magnetic field . 36
11.3.1 General . 36
11.3.2 Reference level of magnetic field . 36
11.3.3 Prediction of magnetic field . 36
11.3.4 Mitigation measures of magnetic field . 37
11.4 Corona noise (audible noise with corona discharge) . 37
11.4.1 General . 37
11.4.2 Characteristics of corona noise . 37
11.4.3 Reference level of corona noise . 37
11.4.4 Prediction of corona noise . 38
11.4.5 Mitigation measures of corona noise . 38
11.5 Radio interference with corona discharge . 38
11.5.1 General . 38
11.5.2 Characteristics of radio interference . 38
11.5.3 Reference level of radio interference . 39
11.5.4 Prediction of radio interference . 39
11.5.5 Mitigation measures of radio interference . 39

– 4 – IEC TS 63042-202:2021 © IEC 2021
11.6 Wind noise . 39
Annex A (informative) Experimental results and c
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