IEC TR 62543:2011/AMD2:2017

Amendment 2 - High-voltage direct current (HVDC) power transmission using voltage sourced converters (VSC)

General Information

• Status: Published
• Publication Date: 22-May-2017
• ICS: 29.200 - Rectifiers. Convertors. Stabilized power supply
• ICS: 29.240.99 - Other equipment related to power transmission and distribution networks
• Technical Committee: SC 22F - Power electronics for electrical transmission and distribution systems
• Drafting Committee: MT 23 - TC 22/SC 22F/MT 23
• Current Stage: DELPUB - Deleted Publication
• Start Date: 30-Mar-2022
• Completion Date: 26-Oct-2025

Relations

• Amends: IEC TR 62543:2011 - High-voltage direct current (HVDC) power transmission using voltage sourced converters (VSC)
• Effective Date: 05-Sep-2023
• Revised: IEC TR 62543:2022 - High-voltage direct current (HVDC) power transmission using voltage sourced converters (VSC)
• Effective Date: 05-Sep-2023

Overview

IEC TR 62543:2011/AMD2:2017 (Amendment 2) provides targeted updates to the IEC technical report on high-voltage direct current (HVDC) power transmission using voltage sourced converters (VSC). This amendment clarifies terminology, updates references, revises figures and topological descriptions, and supplements guidance on modulation, harmonics and converter losses to better support system designers, manufacturers and test laboratories.

Key Topics

• Normative references updated: IEC 60633 is superseded by IEC 62747 for VSC terminology; new references include IEC 62501 (VSC valve electrical testing) and the IEC 62751 series (VSC valve power losses).
• Terms & definitions: The amendment re-directs basic VSC terminology to IEC 62747 and testing terminology to IEC 62501 and modifies the Terms section accordingly.
• Revised figures and topologies: Major component diagrams for VSC substations and common VSC transmission configurations (monopole, bipole, parallel converters) are replaced to reflect current practice.
• Converter design and components: Updates address MMC (modular multilevel converter) submodules, valve reactor placement and optional functions, interface transformer considerations, and the requirement for balancing control of submodule capacitors.
• Control and protection: Notes added on MMC balancing control and valve reactor locations; converter operating tests are retitled and clarified.
• Modulation and harmonics: Annex B has been replaced with detailed discussion of 2-level modulation strategies (carrier wave PWM and selective harmonic elimination). Harmonic interaction guidance points readers to the IEC 62001 series for network harmonic data and impedance considerations.
• Losses and testing: Converter power-loss guidance now references the IEC 62751 series instead of IEC 61803, with specific parts addressing general and MMC loss calculations.

Applications

This amendment has practical value for:

• HVDC system designers implementing VSC topologies (2-level, MMC) and planning converter layouts.
• Laboratories and manufacturers preparing electrical tests for VSC valves in line with IEC 62501.
• Grid planners and filter designers performing harmonic studies and specifying AC filters using guidance from IEC 62001.
• Control engineers designing MMC balancing algorithms to avoid capacitor voltage unbalance and ensure equipment ratings.
• Renewable integration projects, including wind farm collections, where the amendment clarifies replacement of "chopper circuit" references with "dynamic braking system" in supply scenarios.

Related Standards

• IEC 62747 - Terminology for VSC for HVDC systems
• IEC 62501 - VSC valve electrical testing
• IEC 62751 (all parts) - Power losses in VSC valves (general and MMC-specific)
• IEC 62001 (all parts) - Guidance on AC filter specification and network harmonic data

This amendment refines practical guidance without changing the base publication's core scope, ensuring clearer terminology, updated normative links and improved design, testing and harmonic guidance for VSC-based HVDC systems.

Standards Content (Sample)

IEC TR 62543 ®
Edition 1.0 2017-05
TECHNICAL
REPORT
colour
inside
AMENDMENT 2
High-voltage direct current (HVDC) power transmission using voltage sourced
converters (VSC)
IEC TR 62543:2013-07/AMD2:2017-05(en)

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Central Office Tel.: [phone]
3, rue de Varembé Fax: [phone]
CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing 20 000 terms and definitions in
Technical Specifications, Technical Reports and other English and French, with equivalent terms in 16 additional
documents. Available for PC, Mac OS, Android Tablets and languages. Also known as the International Electrotechnical
iPad. Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a 65 000 electrotechnical terminology entries in English and
variety of criteria (reference number, text, technical French extracted from the Terms and Definitions clause of
committee,…). It also gives information on projects, replaced IEC publications issued since 2002. Some entries have been
and withdrawn publications. collected from earlier publications of IEC TC 37, 77, 86 and

CISPR.
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Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: [e-mail].
IEC TR 62543 ®
Edition 1.0 2017-05
TECHNICAL
REPORT
colour
inside
AMENDMENT 2
High-voltage direct current (HVDC) power transmission using voltage sourced

converters (VSC)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.200; 29.240.99 ISBN 978-2-8322-4350-3

– 2 – IEC TR 62543:2011/AMD2:2017
 IEC 2017
FOREWORD
This amendment has been prepared by subcommittee 22F: Power electronics for electrical
transmission and distribution systems, of IEC technical committee 22: Power electronic
systems and equipment.
The text of this amendment is based on the following documents:
DTR Report on voting
22F/440/DTR 22F/450/RVDTR
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

A bilingual version of this publication may be issued at a later date.
_____________
2 Normative references
Replace the existing reference "IEC 60633, Terminology for high-voltage direct-current
(HVDC) transmission" by the following new reference: "IEC 62747, Terminology for voltage-
sourced converters (VSC) for high-voltage direct current (HVDC) systems".
Add the following new references:
IEC 62501, Voltage sourced converter (VSC) valves for high-voltage direct current (HVDC)
power transmission – Electrical testing
IEC 62751 (all parts), Power losses in voltage sourced converter (VSC) valves for high
voltage direct current (HVDC) systems

 IEC 2017
3 Terms and definitions
Replace the existing sentence by the following new sentence:
For the purposes of this document, the terms and definitions given in IEC 62747, IEC 62501
and the following apply.
3.1 General
Insert the following text just after the title of 3.1:
Basic terms and definitions for voltage sourced converters used for HVDC transmission are
given in IEC 62747. Terminology on electrical testing of VSC valves for HVDC transmission is
given in IEC 62501.
Delete the first paragraph of the note. Change the second paragraph of the note into normal
paragraph text.
Figure 1 – Major components that may be found in a VSC substation
Replace the existing figure and its footnotes modified by IEC TR 62543:2011/AMD1:2013 by
the following new figure and footnotes:
IEC
3)
1 circuit breaker 9 VSC unit
4)
2 pre-Insertion Resistor 10 VSC d.c. capacitor

1) 1)
3 line side harmonic filter 11 d.c. harmonic filter
6) 7)
4 line side high frequency filter 12 dynamic braking system
5)
5 interface transformer 13 neutral point grounding branch
1) 8)
6 converter side harmonic filter 14 d.c. reactor
2)
7 + 8 converter side high frequency filter 15 d.c. cable or overhead transmission line
2)
8 phase reactor
– 4 – IEC TR 62543:2011/AMD2:2017
 IEC 2017
1)
In some designs of VSC based on "controllable voltage source" valves, the harmonic filters may not be

required.
2)
In some designs of VSC, the phase reactor may fulfill part of the function of the converter-side high frequency
filter.
3)
In some VSC topologies, each valve of the VSC unit may include a "valve reactor", which may be built into the
valve or provided as a separate component.
4)
In some designs of VSC, the VSC d.c. capacitor may be partly or entirely distributed amongst the three phase
units of the VSC Unit, where it is referred to as the d.c. submodule capacitors.
5)
The philosophy and location of the neutral point grounding branch may be different depending on the design of
the VSC unit.
6)
In some designs of VSC, the interface transformer may fulfill part of the function of the line-side high frequency
filter.
7)
Optional.
8)
Optional, if phase reactors are located on the d.c. side of the converter.
3.3 Power semiconductor terms
Delete the existing sub-clause, modified by IEC TR 62543:2011/AMD1:2013, including its title.
3.4 VSC topologies
Delete the existing sub-clause, modified by IEC TR 62543:2011/AMD1:2013, including its title.
3.5 VSC transmission
Delete items 3.5.1 to 3.5.3, 3.5.5, 3.5.7 and 3.5.9 modified by
IEC TR 62543:2011/AMD1:2013.
3.6 Operating states
Delete the existing sub-clause, modified by IEC TR 62543:2011/AMD1:2013, including its title.
3.10 Insulation co-ordination terms
Delete the existing sub-clause, including its title.
4.1.2.1 General
Replace, in the last paragraph, the first sentence by the following new sentence:
The active and reactive power are related to the AC voltages U and U of the AC system
L conv
and converter respectively, the reactance X between these voltages and the phase angle δ
between them, according to the following:
U ×U × sinδ
L conv
P=
X
U × (U −U × cosδ
L L conv
Q=
X
Move the second and third sentences of the last paragraph on a new line to become a fourth
paragraph.
4.1.3 Operating principles of a VSC transmission scheme
Add, at the beginning of the first sentence of the last paragraph, the words "For example,".

 IEC 2017
4.1.4 Applications of VSC transmission
Add, at the beginning of the first sentence of the third bullet point of the subclause, the words
"In most cases,".
Figure 7 – VSC transmission with an asymmetrical monopole with metallic return
Replace the existing figure by the following new figure:
IEC
Figure 8 – VSC transmission with an asymmetrical monopole with earth return
Replace the existing figure by the following new figure:
IEC
Figure 9 – VSC transmission in bipolar configuration
Replace the existing figure by the following new figure:
IEC
Figure 10 – Parallel connection of two converter units
Replace the existing figure by the following new figure:

----------------------
...

IEC TR 62543 ®
Edition 1.0 2017-05
TECHNICAL
REPORT
colour
inside
AMENDMENT 2
High-voltage direct current (HVDC) power transmission using voltage sourced
converters (VSC)
IEC TR 62543:2013-07/AMD2:2017-05(en)

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form

or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or

your local IEC member National Committee for further information.

IEC Central Office Tel.: [phone]
3, rue de Varembé Fax: [phone]

CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing 20 000 terms and definitions in
Technical Specifications, Technical Reports and other English and French, with equivalent terms in 16 additional
documents. Available for PC, Mac OS, Android Tablets and languages. Also known as the International Electrotechnical
iPad. Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a 65 000 electrotechnical terminology entries in English and
variety of criteria (reference number, text, technical French extracted from the Terms and Definitions clause of
committee,…). It also gives information on projects, replaced IEC publications issued since 2002. Some entries have been
and withdrawn publications. collected from earlier publications of IEC TC 37, 77, 86 and

CISPR.
IEC Just Published - webstore.iec.ch/justpublished

Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: [e-mail].
IEC TR 62543 ®
Edition 1.0 2017-05
TECHNICAL
REPORT
colour
inside
AMENDMENT 2
High-voltage direct current (HVDC) power transmission using voltage sourced

converters (VSC)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.200; 29.240.99 ISBN 978-2-8322-4350-3

– 2 – IEC TR 62543:2011/AMD2:2017

 IEC 2017
FOREWORD
This amendment has been prepared by subcommittee 22F: Power electronics for electrical

transmission and distribution systems, of IEC technical committee 22: Power electronic

systems and equipment.
The text of this amendment is based on the following documents:

DTR Report on voting
22F/440/DTR 22F/450/RVDTR
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

A bilingual version of this publication may be issued at a later date.
_____________
2 Normative references
Replace the existing reference "IEC 60633, Terminology for high-voltage direct-current
(HVDC) transmission" by the following new reference: "IEC 62747, Terminology for voltage-
sourced converters (VSC) for high-voltage direct current (HVDC) systems".
Add the following new references:
IEC 62501, Voltage sourced converter (VSC) valves for high-voltage direct current (HVDC)
power transmission – Electrical testing
IEC 62751 (all parts), Power losses in voltage sourced converter (VSC) valves for high
voltage direct current (HVDC) systems

 IEC 2017
3 Terms and definitions
Replace the existing sentence by the following new sentence:

For the purposes of this document, the terms and definitions given in IEC 62747, IEC 62501

and the following apply.
3.1 General
Insert the following text just after the title of 3.1:

Basic terms and definitions for voltage sourced converters used for HVDC transmission are
given in IEC 62747. Terminology on electrical testing of VSC valves for HVDC transmission is
given in IEC 62501.
Delete the first paragraph of the note. Change the second paragraph of the note into normal
paragraph text.
Figure 1 – Major components that may be found in a VSC substation
Replace the existing figure and its footnotes modified by IEC TR 62543:2011/AMD1:2013 by
the following new figure and footnotes:

IEC
3)
1 circuit breaker 9 VSC unit
4)
2 pre-Insertion Resistor 10 VSC d.c. capacitor

1) 1)
3 line side harmonic filter 11 d.c. harmonic filter
6) 7)
4 line side high frequency filter 12 dynamic braking system
5)
5 interface transformer 13 neutral point grounding branch
1) 8)
6 converter side harmonic filter 14 d.c. reactor
2)
7 + 8 converter side high frequency filter 15 d.c. cable or overhead transmission line
2)
8 phase reactor
– 4 – IEC TR 62543:2011/AMD2:2017

 IEC 2017
1)
In some designs of VSC based on "controllable voltage source" valves, the harmonic filters may not be

required.
2)
In some designs of VSC, the phase reactor may fulfill part of the function of the converter-side high frequency

filter.
3)
In some VSC topologies, each valve of the VSC unit may include a "valve reactor", which may be built into the

valve or provided as a separate component.
4)
In some designs of VSC, the VSC d.c. capacitor may be partly or entirely distributed amongst the three phase
units of the VSC Unit, where it is referred to as the d.c. submodule capacitors.

5)
The philosophy and location of the neutral point grounding branch may be different depending on the design of
the VSC unit.
6)
In some designs of VSC, the interface transformer may fulfill part of the function of the line-side high frequency
filter.
7)
Optional.
8)
Optional, if phase reactors are located on the d.c. side of the converter.
3.3 Power semiconductor terms
Delete the existing sub-clause, modified by IEC TR 62543:2011/AMD1:2013, including its title.
3.4 VSC topologies
Delete the existing sub-clause, modified by IEC TR 62543:2011/AMD1:2013, including its title.
3.5 VSC transmission
Delete items 3.5.1 to 3.5.3, 3.5.5, 3.5.7 and 3.5.9 modified by
IEC TR 62543:2011/AMD1:2013.
3.6 Operating states
Delete the existing sub-clause, modified by IEC TR 62543:2011/AMD1:2013, including its title.
3.10 Insulation co-ordination terms
Delete the existing sub-clause, including its title.
4.1.2.1 General
Replace, in the last paragraph, the first sentence by the following new sentence:
The active and reactive power are related to the AC voltages U and U of the AC system
L conv
and converter respectively, the reactance X between these voltages and the phase angle δ

between them, according to the following:
U ×U × sinδ
L conv
P=
X
U × (U −U × cosδ
L L conv
Q=
X
Move the second and third sentences of the last paragraph on a new line to become a fourth
paragraph.
4.1.3 Operating principles of a VSC transmission scheme
Add, at the beginning of the first sentence of the last paragraph, the words "For example,".

 IEC 2017
4.1.4 Applications of VSC transmission

Add, at the beginning of the first sentence of the third bullet point of the subclause, the words

"In most cases,".
Figure 7 – VSC transmission with an asymmetrical monopole with metallic return

Replace the existing figure by the following new figure:

IEC
Figure 8 – VSC transmission with an asymmetrical monopole with earth return
Replace the existing figure by the following new figure:
IEC
Figure 9 – VSC transmission in bipolar configuration
Replace the existing figure by the following new figure:

IEC
Figure 10 – Parallel connection of two converter units
Replace the existing figure by the following new figure:

---
...