IEC TS 63042-102:2021

IEC TS 63042-102 ®
Edition 1.0 2021-08
TECHNICAL
SPECIFICATION
colour
inside
UHV AC transmission systems –
Part 102: General system design
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IEC TS 63042-102 ®
Edition 1.0 2021-08
TECHNICAL
SPECIFICATION
colour
inside
UHV AC transmission systems –
Part 102: General system design

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.01; 29.240.10 ISBN 978-2-8322-1012-7

– 2 – IEC TS 63042-102:2021 © IEC 2021
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 9
4 Objective and key issues of UHV AC transmission application . 9
4.1 Objective . 9
4.2 Key application issues . 10
5 Required studies on UHV AC system planning and design . 10
5.1 General . 10
5.2 Required studies . 11
5.3 Required analysis tools . 11
6 UHV AC system planning . 13
6.1 General . 13
6.1.1 Introductory remarks . 13
6.1.2 Transmission capacity considering routes and line types to use . 13
6.1.3 Reactive power management issues . 13
6.1.4 Environmental issues . 14
6.2 Scenario for system planning . 15
6.3 Scenario for network planning procedure . 15
6.3.1 Power transmission capacity . 15
6.3.2 System voltage . 16
6.3.3 Route selection . 16
6.3.4 Series compensation . 17
6.4 Required parameters . 17
6.5 Transmission network (topology) . 17
6.6 Reliability . 18
7 UHV AC system design. 19
7.1 General . 19
7.2 Reactive power management . 19
7.3 Reclosing schemes . 19
7.4 Delayed current zero phenomenon . 21
7.5 Protection and control system . 22
7.6 Insulation design (cost effectiveness) . 22
Annex A (informative) History of development of UHV AC transmission technologies . 24
A.1 General . 24
A.2 History of development in the USA . 24
A.3 History of development in former USSR and Russia . 24
A.4 History of development in Italy . 24
A.5 History of development in Japan . 25
A.6 History of development in China . 25
A.7 History of development in India . 25
Annex B (informative) Experiences relating to UHV AC transmission development. 26
B.1 Project development in Italy . 26
B.1.1 Background (including network development) . 26
B.1.2 Demand analysis and scenario of application. 26

B.1.3 Project overview . 26
B.1.4 UHV system planning . 27
B.1.5 UHV system design . 28
B.1.6 Laboratory and field tests . 29
B.2 Project development in China . 32
B.2.1 Background . 32
B.2.2 Project overview . 32
B.2.3 Changzhi-Nanyang-Jingmen UHV AC extension project . 33
B.2.4 Overvoltage mitigation and insulation coordination . 35
B.2.5 Insulation coordination . 36
B.2.6 Laboratory and field tests . 38
B.3 Project development in India . 40
B.3.1 Background (including network development) . 40
B.3.2 Demand analysis and scenario of application. 40
B.3.3 Project overview . 40
B.3.4 Development of 1 200 kV national test station in India . 41
B.3.5 POWERGRID's 1 200 kV transmission system . 42
B.3.6 UHV AC technology design – Insulation coordination . 43
B.3.7 Insulation design for substation . 44
B.4 Project development in Japan . 45
B.4.1 Background (including network development) . 45
B.4.2 Demand analysis and scenario of application. 46
B.4.3 Project overview . 46
B.4.4 UHV system planning . 47
B.4.5 UHV system design . 47
B.4.6 Laboratory and field tests . 50
Annex C (informative) Summary of system technologies specific to UHV AC
transmission systems . 53
C.1 Technologies used in China . 53
C.1.1 Transformer . 53
C.1.2 UHV shunt reactor and reactive compensation at tertiary side of
transformer . 54
C.1.3 Switchgear . 55
C.1.4 Series capacitor (SC) . 57
C.1.5 Gas-insulated transmission line (GIL) . 59
C.2 Technologies used in India . 60
C.2.1 UHV AC transformer . 60
C.2.2 Surge arrester . 61
C.2.3 Circuit-breakers . 62
C.2.4 Instrument transformers . 63
C.3 Technologies used in Japan . 64
C.3.1 Switch gear . 64
C.3.2 Surge arrester . 65
Bibliography . 67

Figure 1 – Analysis tool by time domain . 12
Figure 2 – Flowchart of reactive power compensation configuration . 14
Figure 3 – π equivalent circuit . 15
Figure 4 – Four-legged reactor . 20

– 4 – IEC TS 63042-102:2021 © IEC 2021
Figure 5 – One typical reclosing sequence of high speed earthing switches (HSESs) . 21
Figure 6 – Procedure for insulation design . 23
Figure B.1 – Demand situation in Italy. 26
Figure B.2 – UHV transmission lines in Italy as originally planned in '70 . 27
Figure B.3 – SPIRA system and SICRE system .
...