IEC TR 60919-2:2008

Performance of high-voltage direct current (HVDC) systems with line-commutated converters - Part 2: Faults and switching

IEC/TR 60919-2:2008 provides guidance on the transient performance and fault protection requirements of high voltage direct current (HVDC) systems. It concerns the transient performance related to faults and switching for two-terminal HVDC systems utilizing 12-pulse converter units comprised of three-phase bridge (double way) connections but it does not cover multi-terminal HVDC transmission systems. However, certain aspects of parallel converters and parallel lines, if part of a two-terminal system, are discussed. The converters are assumed to use thyristor valves as the bridge arms, with gapless metal oxide arresters for insulation co-ordination and to have power flow capability in both directions. Diode valves are not considered in this report. This second edition cancels and replaces the first edition, published in 1991, and constitutes a technical revision. It includes the following main changes with respect to the previous edition: it concerns only line-commutated converters;isignificant changes have been made to the control system technology; some environmental constraints, for example audible noise limits, have been added; the capacitor coupled converters (CCC) and controlled series capacitor converters (CSCC) have been included.

Fonctionnement des systèmes à courant continu haute tension (CCHT) munis de convertisseurs commutés par le réseau - Partie 2: Défauts et manoeuvres

La CEI/TR 60919-2:2008 fournit des indications générales sur les performances de fonctionnement transitoire et sur les exigences de protection contre les défauts pour les systèmes à courant continu haute tension (CCHT). Il se rapporte au fonctionnement transitoire lié aux défauts et manoeuvres dans le cas des systèmes CCHT à deux extrémités, utilisant des convertisseurs à 12 impulsions comprenant des ponts de Graetz hexaphasés mais ne couvre pas les systèmes de transmission CCHT multiterminaux. Cependant, certains aspects liés à la mise en parallèle de convertisseurs et de lignes, s'ils relèvent d'un système à deux extrémités, seront également abordés. Les convertisseurs sont supposés utiliser des valves à thyristors dans les bras de pont, avec des parafoudres à oxyde métallique sans éclateur pour la coordination de l'isolement, et permettre le transport d'énergie dans les deux sens. Les valves à diode ne sont pas prises en considération dans le présent rapport. Cette deuxième édition annule et remplace la première édition, parue en 1991, et constitue une révision technique. Elle contient les changements fondamentaux suivants par rapport à l'édition précédente: elle ne concerne que les convertisseurs commutés par le réseau; des changements significatifs ont été effectués pour la technologie du système de contrôle; certaines limites environnementales ont été introduites, par exemple les niveaux de bruit audible maximaux; les convertisseurs connectés au travers de condensateurs (CCC) et les convertisseurs à condensateurs en série contrôles (CCSC) ont été ajoutés.

General Information

• Status: Published
• Publication Date: 26-Apr-2020
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• 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
• Current Stage: PPUB - Publication issued
• Start Date: 15-Dec-2008
• Completion Date: 05-Nov-2008

Relations

• Amended By: IEC TR 60919-2:2008/AMD2:2020 - Amendment 2 - Performance of high-voltage direct current (HVDC) systems with line-commutated converters - Part 2: Faults and switching
• Effective Date: 05-Sep-2023
• Amended By: IEC TR 60919-2:2008/AMD1:2015 - Amendment 1 - Performance of high-voltage direct current (HVDC) systems with line-commutated converters - Part 2: Faults and switching
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC TR 60919-2 ®
Edition 2.2 2020-04
CONSOLIDATED VERSION
TECHNICAL
REPORT
colour
inside
Performance of high-voltage direct current (HVDC) systems with line-
commutated converters –
Part 2: Faults and switching
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 [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
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
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IEC Customer Service Centre - webstore.iec.ch/csc entries have been collected from earlier publications of IEC
If you wish to give us your feedback on this publication or TC 37, 77, 86 and CISPR.

need further assistance, please contact the Customer Service

Centre: [e-mail].
IEC TR 60919-2 ®
Edition 2.2 2020-04
CONSOLIDATED VERSION
TECHNICAL
REPORT
colour
inside
Performance of high-voltage direct current (HVDC) systems with line-

commutated converters –
Part 2: Faults and switching
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.200; 29.240.99 ISBN 978-2-8322-8263-2

IEC TR 60919-2 ®
Edition 2.2 2020-04
CONSOLIDATED VERSION
REDLINE VERSION
colour
inside
Performance of high-voltage direct current (HVDC) systems with line-
commutated converters –
Part 2: Faults and switching
– 2 – IEC TR 60919-2:2008+AMD1:2015
+AMD2:2020 CSV  IEC 2020
CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references . 9
3 Outline of HVDC transient performance specifications . 9
3.1 Transient performance specifications . 9
3.2 General comment . 10
4 Switching transients without faults . 10
4.1 General . 10
4.2 Energization and de-energization of a.c. side equipment . 10
4.3 Load rejection . 12
4.4 Start-up and shut-down of converter units . 13
4.5 Operation of d.c. breakers and d.c. switches . 13
5 AC system faults . 16
5.1 General . 16
5.2 Fault categories . 16
5.3 Specification matters affecting transient performance . 16
5.3.1 Effective a.c. system impedance . 16
5.3.2 Power transfer during faults . 17
5.3.3 Recovery following fault clearing . 17
5.3.4 Reactive power consumption during fault and post-fault recovery
periods . 18
5.3.5 Load rejection due to a.c. faults . 18
5.3.6 Switching of reactive power equipment . 19
5.3.7 Effects of harmonic voltages and current during faults . 19
5.3.8 Shift in control modes of operation . 20
5.3.9 Power modulation on the HVDC system . 20
5.3.10 Emergency power reductions . 20
5.4 Specification impact on control strategy . 20
6 AC filters, reactive power equipment and a.c. bus faults . 22
6.1 General . 22
6.2 Transient overvoltages in filter banks . 22
6.3 Transient overcurrents in filter and capacitor banks . 23
6.4 Capacitor unbalance protection . 23
6.5 Examples of protection of filters and capacitor banks . 24
6.6 Shunt reactor protection . 25
6.7 AC bus protection . 25
7 Converter unit faults . 27
7.1 General . 27
7.2 Short circuits . 27
7.3 Failure of converter unit to perform its intended function . 29
7.3.1 General . 29
7.3.2 Rectifier operation . 29
7.3.3 Inverter operation . 29
7.4 Converter unit protection . 30
7.4.1 Converter differential protection . 30
7.4.2 Overcurrent protection . 30

+AMD2:2020 CSV  IEC 2020
7.4.3 AC overvoltage protection . 30
7.4.4 Protection against large delay angle operation . 30
7.4.5 Commutation failure protection . 30
7.4.6 Thyristor valve protections . 30
7.4.7 Transformer protection . 30
7.4.8 Transformer tap-changer unbalance protection . 31
7.4.9 AC connection earth fault protection . 31
7.5 Additional protection aspects of series connected converter units . 31
7.6 Additional protection aspects of parallel connected converter units . 31
8 DC reactor, d.c. filter and other d.c. equipment faults . 34
8.1 General . 34
8.2 Fault types . 34
8.3 Protection zones . 34
8.4 Neutral protection . 35
8.4.1 General . 35
8.4.2 Neutral fault detection . 35
8.4.3 Neutral bus fault isolation . 35
8.4.4 Bipolar neutral bus faults . 35
8.5 DC reactor protection . 36
8.6 DC harmonic filter protection . 36
8.6.1 General . 36
8.6.2 Filter bank fault protection . 36
8.6.3 DC filter capacitor unit protection. 37
8.7 DC harmonic protection . 37
8.8 DC overvoltage protection . 37
8.9 DC side switching protection . 37
9 DC line faults . 40
9.1 Overhead line faults . 40
9.2 Cable faults . 41
9.3 DC fault characteristics . 41
9.4 Functional d.c. fault detection requirements . 41
9.5 Protective sequence . 42
9.5.1 Overhead line faults . 42
9.5.2 Faults in cable systems . 42
9.5.3 Faults in an overhead line/cable system . 42
9.5.4 Faults in one of a system of parallel-connected cables . 42
9.5.5 Fault in a system of parallel overhead lines . 43
9.6 Fault protection schemes . 43
9.7 Open circuit on the d.c. side . 43
9.8 Power line cross protection . 44
10 Earth electrode line faults . 44
10.1 General . 44
10.2 Specific requirements – Earth electrode line . 44
10.3 Electrode line supervision . 45
11 Metallic return conductor faults . 45
11.1 Conductor for the return circuit . 45
11.2 Metallic return faults . 45
11.3 Fault detection – Metallic return .
...

IEC/TR 60919-2
Edition 2.0 2008-11
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
Performance of high-voltage direct current (HVDC) systems with line-
commutated converters –
Part 2: Faults and switching
Fonctionnement des systèmes à courant continu haute tension (CCHT) munis
de convertisseurs commutés par le réseau –
Partie 2: Défauts et manœuvres

IEC/TR 60919-2:2008
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.

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IEC/TR 60919-2
Edition 2.0 2008-11
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
Performance of high-voltage direct current (HVDC) systems with line-
commutated converters –
Part 2: Faults and switching
Fonctionnement des systèmes à courant continu haute tension (CCHT) munis
de convertisseurs commutés par le réseau –
Partie 2: Défauts et manœuvres

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XB
CODE PRIX
ICS 29.200; 29.240.99 ISBN 978-2-88910-331-7
– 2 – TR 60919-2 © IEC:2008
CONTENTS
FOREWORD.6
1 Scope.8
2 Normative references .9
3 Outline of HVDC transient performance specifications .9
3.1 Transient performance specifications .9
3.2 General comment .10
4 Switching transients without faults.10
4.1 General .10
4.2 Energization and de-energization of a.c. side equipment .10
4.3 Load rejection .12
4.4 Start-up and shut-down of converter units .13
4.5 Operation of d.c. breakers and d.c. switches .13
5 AC system faults .15
5.1 General .15
5.2 Fault categories .16
5.3 Specification matters affecting transient performance.16
5.3.1 Effective a.c. system impedance.16
5.3.2 Power transfer during faults.16
5.3.3 Recovery following fault clearing .17
5.3.4 Reactive power consumption during fault and post-fault recovery
periods .18
5.3.5 Load rejection due to a.c. faults.18
5.3.6 Switching of reactive power equipment .19
5.3.7 Effects of harmonic voltages and current during faults .19
5.3.8 Shift in control modes of operation .19
5.3.9 Power modulation on the HVDC system.20
5.3.10 Emergency power reductions.20
5.4 Specification impact on control strategy .20
6 AC filters, reactive power equipment and a.c. bus faults .21
6.1 General .21
6.2 Transient overvoltages in filter banks .21
6.3 Transient overcurrents in filter and capacitor banks.22
6.4 Capacitor unbalance protection .23
6.5 Examples of protection of filters and capacitor banks .23
6.6 Shunt reactor protection .24
6.7 AC bus protection.24
7 Converter unit faults .27
7.1 General .27
7.2 Short circuits .27
7.3 Failure of converter unit to perform its intended function .28
7.3.1 General .28
7.3.2 Rectifier operation .28
7.3.3 Inverter operation .29
7.4 Converter unit protection .29
7.4.1 Converter differential protection.29
7.4.2 Overcurrent protection.29

TR 60919-2 © IEC:2008 – 3 –
7.4.3 AC overvoltage protection .29
7.4.4 Protection against large delay angle operation .29
7.4.5 Commutation failure protection .30
7.4.6 Thyristor valve protections.30
7.4.7 Transformer protection .30
7.4.8 Transformer tap-changer unbalance protection.30
7.4.9 AC connection earth fault protection .30
7.5 Additional protection aspects of series connected converter units .30
7.6 Additional protection aspects of parallel connected converter units .31
8 DC reactor, d.c. filter and other d.c. equipment faults .33
8.1 General .33
8.2 Fault types .34
8.3 Protection zones .34
8.4 Neutral protection.34
8.4.1 General .34
8.4.2 Neutral fault detection .34
8.4.3 Neutral bus fault isolation .35
8.4.4 Bipolar neutral bus faults .35
8.5 DC reactor protection .35
8.6 DC harmonic filter protection .35
8.6.1 General .35
8.6.2 Filter bank fault protection .36
8.6.3 DC filter capacitor unit protection.36
8.7 DC harmonic protection.36
8.8 DC overvoltage protection .36
8.9 DC side switching protection .37
9 DC line faults.38
9.1 Overhead line faults .38
9.2 Cable faults .39
9.3 DC fault characteristics .39
9.4 Functional d.c. fault detection requirements .40
9.5 Protective sequence.40
9.5.1 Overhead line faults .40
9.5.2 Faults in cable systems .40
9.5.3 Faults in an overhead
...

IEC TR 60919-2 ®
Edition 2.1 2015-06
CONSOLIDATED VERSION
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
colour
inside
Performance of high-voltage direct current (HVDC) systems with line-
commutated converters –
Part 2: Faults and switching
Fonctionnement des systèmes à courant continu haute tension (CCHT) munis
de convertisseurs commutés par le réseau –
Partie 2: Défauts et manoeuvres

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.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

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3, rue de Varembé Fax: [phone]
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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.

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Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

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[e-mail].
IEC TR 60919-2 ®
Edition 2.1 2015-06
CONSOLIDATED VERSION
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
colour
inside
Performance of high-voltage direct current (HVDC) systems with line-

commutated converters –
Part 2: Faults and switching
Fonctionnement des systèmes à courant continu haute tension (CCHT) munis

de convertisseurs commutés par le réseau –

Partie 2: Défauts et manoeuvres

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.200; 29.240.99 ISBN 978-2-8322-2762-6

IEC TR 60919-2 ®
Edition 2.1 2015-06
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Performance of high-voltage direct current (HVDC) systems with line-
commutated converters –
Part 2: Faults and switching
Fonctionnement des systèmes à courant continu haute tension (CCHT) munis
de convertisseurs commutés par le réseau –
Partie 2: Défauts et manoeuvres

– 2 – IEC TR 60919-2:2008
+AMD1:2015 CSV  IEC 2015
CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references . 9
3 Outline of HVDC transient performance specifications . 9
3.1 Transient performance specifications . 9
3.2 General comment . 10
4 Switching transients without faults . 10
4.1 General . 10
4.2 Energization and de-energization of a.c. side equipment . 10
4.3 Load rejection . 12
4.4 Start-up and shut-down of converter units . 13
4.5 Operation of d.c. breakers and d.c. switches . 13
5 AC system faults . 15
5.1 General . 15
5.2 Fault categories . 16
5.3 Specification matters affecting transient performance . 16
5.3.1 Effective a.c. system impedance . 16
5.3.2 Power transfer during faults . 16
5.3.3 Recovery following fault clearing . 17
5.3.4 Reactive power consumption during fault and post-fault recovery
periods . 18
5.3.5 Load rejection due to a.c. faults . 18
5.3.6 Switching of reactive power equipment . 19
5.3.7 Effects of harmonic voltages and current during faults . 19
5.3.8 Shift in control modes of operation . 19
5.3.9 Power modulation on the HVDC system . 20
5.3.10 Emergency power reductions . 20
5.4 Specification impact on control strategy . 20
6 AC filters, reactive power equipment and a.c. bus faults . 22
6.1 General . 22
6.2 Transient overvoltages in filter banks . 22
6.3 Transient overcurrents in filter and capacitor banks . 23
6.4 Capacitor unbalance protection . 23
6.5 Examples of protection of filters and capacitor banks . 24
6.6 Shunt reactor protection . 25
6.7 AC bus protection . 25
7 Converter unit faults . 27
7.1 General . 27
7.2 Short circuits . 27
7.3 Failure of converter unit to perform its intended function . 29
7.3.1 General . 29
7.3.2 Rectifier operation . 29
7.3.3 Inverter operation . 29
7.4 Converter unit protection . 30
7.4.1 Converter differential protection . 30
7.4.2 Overcurrent protection . 30

+AMD1:2015 CSV  IEC 2015
7.4.3 AC overvoltage protection . 30
7.4.4 Protection against large delay angle operation . 30
7.4.5 Commutation failure protection . 30
7.4.6 Thyristor valve protections . 30
7.4.7 Transformer protection . 30
7.4.8 Transformer tap-changer unbalance protection . 31
7.4.9 AC connection earth fault protection . 31
7.5 Additional protection aspects of series connected converter units . 31
7.6 Additional protection aspects of parallel connected converter units . 31
8 DC reactor, d.c. filter and other d.c. equipment faults . 34
8.1 General . 34
8.2 Fault types . 34
8.3 Protection zones . 34
8.4 Neutral protection . 35
8.4.1 General . 35
8.4.2 Neutral fault detection . 35
8.4.3 Neutral bus fault isolation . 35
8.4.4 Bipolar neutral bus faults
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