IEC TR 63502:2024

Guidelines for parameters measurement of HVDC transmission line

IEC TR 63502:2024, which is a Technical Report, gives information relevant to the on-site HVDC transmission line parameter measurement. HVDC transmission line can be overhead lines, land or submarine cables, or hybrid lines with overhead line section(s) and cable section(s) (or any combination of these). This document introduces measurement specification, including measurement conditions, safety precautions, measurement instrument, measurement methods, etc., in order to measure the parameters of HVDC overhead transmission line and cable with a DC voltage level above 100 kV.
This document is also relevant to line parameter measurement of earth electrode lines in HVDC power transmission systems.

General Information

• Status: Published
• Publication Date: 09-Dec-2024
• ICS: 29.240.20 - Power transmission and distribution lines
• Technical Committee: TC 115 - High Voltage Direct Current (HVDC) transmission for DC voltages above 100 kV
• Current Stage: PPUB - Publication issued
• Start Date: 03-Jan-2025
• Completion Date: 10-Dec-2024

Standards Content (Sample)

IEC TR 63502 ®
Edition 1.0 2024-12
TECHNICAL
REPORT
colour
inside
Guidelines for parameters measurement of HVDC transmission line

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IEC TR 63502 ®
Edition 1.0 2024-12
TECHNICAL
REPORT
colour
inside
Guidelines for parameters measurement of HVDC transmission line

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.20  ISBN 978-2-8327-0070-9

– 2 – IEC TR 63502:2024 © IEC 2024
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 General . 9
4.1 Background. 9
4.2 Measurement items . 10
4.3 Measurement conditions . 10
4.4 Safety precautions . 10
4.5 Measurement instruments . 10
5 Induced voltage and induced current measurement . 11
5.1 General . 11
5.2 Induced voltage measurement . 11
5.3 Induced current measurement . 12
6 Insulation resistance measurement . 12
7 Polarity verification . 13
7.1 Polarity verification method using megohmmeter . 13
7.2 Polarity verification method using a battery . 14
8 Measurement of DC resistance . 14
9 Measurement of frequency characteristics of HVDC transmission line . 16
9.1 General . 16
9.2 Differential mode measurement . 17
9.2.1 Measuring the differential mode short-circuit impedance . 17
9.2.2 Measuring the differential mode open-circuit impedance . 17
9.2.3 Calculating the frequency characteristics of differential mode
parameters . 17
9.3 Common mode measurement . 18
9.3.1 Measuring the common mode short-circuit impedance . 18
9.3.2 Measuring the common mode open-circuit impedance . 18
9.3.3 Calculating the frequency characteristics at common mode parameters . 19
9.4 Calculating the coupling parameters of pole line I and pole line II . 20
10 Measurement of coupling parameters of two bipolar HVDC transmission lines . 20
10.1 Measuring frequency characteristics at differential mode measurement . 20
10.2 Measuring frequency characteristics at common mode measurement. 21
10.3 Calculating the mutual coupling parameters . 22
11 Measurement of frequency characteristics of HVDC transmission line with
dedicated metallic return line . 22
12 Measurement of frequency characteristics of HVDC cable . 24
13 Measurement of earth electrode line parameter . 24
Annex A (informative) Anti-interference measures . 26
Annex B (informative) Method for locating faults of transmission line . 27
B.1 Overview. 27
B.2 Location of earthing faults . 27
B.3 Location of open-circuit faults . 28

B.4 Location of bipolar short-circuit faults . 28
B.5 Location of multiple faults . 29
Annex C (informative) Principle of measuring distributed parameters . 30
C.1 Distributed parameter circuit of the transmission line . 30
C.2 Definitions. 30
C.3 Telegraph equations . 30
C.4 Calculation of distributed parameters . 31
Annex D (informative) Case of measurement of transmission line parameters . 33
D.1 Base data . 33
D.2 Calculating process . 34
D.2.1 General . 34
D.2.2 Calculation of characteristic impedance and transmission constant . 34
D.2.3 Calculation of per unit length value of impedance and admittance . 34
D.2.4 Calculation of parameter in unit length . 35
D.3 Calculation of parameter in unit length under each selected frequency . 35
D.4 Curve fitting . 36
D.4.1 General . 36
D.4.2 R-f curve under the bipolar parallel measuring mode. 36
D.4.3 L-f curve under the bipolar parallel measuring mode . 36
Bibliography . 38

Figure 1 – Induced voltage test with the ending terminal open-circuited . 11
Figure 2 – Induced voltage test with the ending terminal short-circuited . 12
Figure 3 –Induced current test . 12
Figure 4 – Insulation resistance test of pole line I . 13
Figure 5 – Polarity verification of pole line I . 13
Figure 6 – Polarity verification for pole I using battery . 14
Figure 7 – Measurement of DC resistance . 15
Figure 8 – Measurement of DC resistance with dedicated metallic return . 15
Figure 9 – Measurement of differential mode short-circuit impedance . 17
Figure 10 – Measurement of differential mode open-circuit impedance . 17
Figure 11 – Measurement of common mode short-circuit impedance. 19
Figure 12 – Measurement of common mode open-circuit impedance . 19
Figure 13 – Measurement of differential mode short circuit impedance for two bipolar
transmission lines . 21
Figure 14 – Measurement of differential mode open circuit impedance for two bipolar
transmission lines . 21
Figure 15 – Measurement of common mode short circuit impedance for two bipolar
transmission line . 22
Figure 16 – Measurement of common mode open circuit impedance for two bipolar
transmission line . 22
Figure 17 – Measurement of differential mode short-circuit impedance with metallic
return line . 23
Figure 18 – Measurement of differential mode open-circuit impedance with metallic
return line . 23
Figure 19 – Measurement of common mode short-circuit impedance with metallic
return line . 23

– 4 – IEC TR 63502:2024 © IEC 2024
Figure 20 – Measurement of common mode open-circuit impedance with metallic
return line . 24
Figure 21 – Measurement of common mode short-circuit impedance of HVDC cable . 24
Figure 22 – Measurement of common mode open-circuit impedance of HVDC cable . 24
Figure 23 – Equivalent circuit of earth electrode line . 25
Figure A.1 – Anti-interference measures . 26
Figure B.1 – Location of earthing faults . 27
Figure B.2 – Location of open-circuit faults . 28
Figure B.3 – Location of bipolar short circuit faults . 28
Figure C.1 – Distributed parameter circuit of the transmission line .
...