IEC TR 63127:2019

IEC TR 63127 ®
Edition 1.1 2024-04
CONSOLIDATED VERSION
TECHNICAL
REPORT
colour
inside
Guideline for the system design of HVDC converter stations with line-
commutated converters
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IEC TR 63127 ®
Edition 1.1 2024-04
CONSOLIDATED VERSION
TECHNICAL
REPORT
colour
inside
Guideline for the system design of HVDC converter stations with line-
commutated converters
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.01; 29.240.10 ISBN 978-2-8322-8767-5
REDLINE VERSION – 2 – IEC TR 63127:2019+AMD1:2024 CSV
 IEC 2024
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 9
4 Symbols . 10
4.1 Letter symbols for variables . 10
4.2 Subscripts . 11
5 Overview of HVDC system design . 11
5.1 General . 11
5.2 Formulation of system design . 13
5.2.1 HVDC system ratings . 13
5.2.2 HVDC system configuration . 13
5.2.3 Reactive power compensation and control . 13
5.2.4 AC/DC interaction and control. 13
5.2.5 Insulation coordination . 14
5.2.6 AC/DC harmonic filtering . 14
5.2.7 Environmental considerations . 14
5.3 System studies and simulations . 14
6 Determination of design conditions and requirements . 16
6.1 Environmental conditions and requirements . 16
6.2 DC transmission line (cable) and earth electrode . 17
6.2.1 Parameters of DC overhead transmission line . 17
6.2.2 Parameters of DC cable . 18
6.2.3 Parameters of electrode line and ground electrode . 18
6.3 AC system conditions. 18
6.3.1 Operating scenarios of AC/DC system . 18
6.3.2 AC system modelling . 18
6.3.3 Relevant AC system protection . 19
6.3.4 Reactive power supply and absorption . 19
6.3.5 Short-circuit current or capacity . 20
6.3.6 AC bus voltage . 21
6.3.7 AC system frequency . 21
6.3.8 Pre-existing harmonic and negative sequence voltage . 22
6.4 Requirements for HVDC systems arising from AC/DC interaction . 22
6.5 AC system equivalents . 23
6.5.1 General . 23
6.5.2 Equivalent for AC/DC system dynamic or transient simulation . 23
6.5.3 Impedance equivalent for AC filter design . 24
6.5.4 System equivalent for low order harmonic resonance study . 26
7 Main circuit design . 26
7.1 Ratings . 26
7.1.1 Rated power . 26
7.1.2 Rated voltage . 27
7.1.3 Rated current . 28
7.2 Configurations . 28

 IEC 2024
7.2.1 Pole and return path . 28
7.2.2 Converter topology . 29
7.2.3 DC switchyard configuration . 30
7.2.4 Reactive power equipment . 38
7.3 Determination of main circuit parameters . 38
7.3.1 General . 38
7.3.2 Control strategy . 39
7.3.3 Tolerances and errors . 40
7.3.4 Determination of converter transformer impedance . 40
7.3.5 Relative inductive voltage drop (d ) and relative resistive voltage drop
xN
(d ) . 40
rN
7.3.6 Ideal no-load DC voltage . 41
7.3.7 DC voltage and DC current . 41
7.3.8 Rated capacity of converter transformer . 42
7.3.9 Converter transformer taps . 43
7.3.10 Inductance of smoothing reactor . 44
8 Insulation coordination. 44
9 Filter design . 45
9.1 General . 45
9.2 AC filter design . 45
9.3 DC filter design . 45
9.4 Power line carrier (PLC) filters . 46
9.5 Radio frequency interference (RFI) . 46
10 Reactive power compensation and control . 47
10.1 General . 47
10.2 Reactive power consumption . 47
10.2.1 Reactive power consumption calculation . 47
10.2.2 Maximum reactive power consumption . 48
10.2.3 Minimum reactive power consumption . 48
10.3 Determination of reactive power equipment capacity . 48
10.3.1 General . 48
10.3.2 Capacity of reactive power supply equipment . 48
10.3.3 Capacity of reactive power absorption equipment . 48
10.3.4 Sizing of reactive power sub-bank . 49
10.3.5 Sizing of reactive power bank . 49
10.4 Reactive power control . 49
10.4.1 General . 49
10.4.2 Reactive power exchange control/voltage control . 50
10.4.3 Voltage limitation . 50
10.5 Temporary overvoltage control . 51
11 Basic parameters of main equipment . 51
11.1 General . 51
11.2 Converter valves . 51
11.2.1 General . 51
11.2.2 Valve hall environment . 51
11.2.3 Current rating . 52
11.2.4 Voltage rating . 52
11.2.5 Losses of converter valves . 53
11.2.6 Testing requirements . 53

REDLINE VERSION – 4 – IEC TR 63127:2019+AMD1:2024 CSV
 IEC 2024
11.3 Converter transformers . 53
11.3.1 General . 53
11.3.2 Current rating .
...