IEC TS 61973:2012

High voltage direct current (HVDC) substation audible noise

IEC/TS 61973:2012(E) applies to the specification and evaluation of outdoor audible noise from high voltage direct current (HVDC) substations. It is intended to be primarily for the use of the utilities and consultants who are responsible for issuing technical specifications for new HVDC projects with and evaluating designs proposed by prospective contractors. It is primarily intended for HVDC projects with line-commutated converters. Part of this technical specification can also be used for the same purpose for HVDC projects using voltage sourced converters, and for flexible a.c. transmission systems (FACTS) devices such as static Var compensators (SVCs) and static synchronous compensators (STATCOMs).

General Information

• Status: Published
• Publication Date: 08-May-2019
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.240.10 - Substations. Surge arresters
• ICS: 29.240.99 - Other equipment related to power transmission and distribution networks
• Technical Committee: TC 115 - High Voltage Direct Current (HVDC) transmission for DC voltages above 100 kV
• Drafting Committee: JMT 1 - TC 115/JMT 1
• Current Stage: PPUB - Publication issued
• Start Date: 15-Jul-2012
• Completion Date: 05-Apr-2012

Relations

• Amended By: IEC TS 61973:2012/AMD1:2019 - Amendment 1 - High voltage direct current (HVDC) substation audible noise
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC/TS 61973 ®
Edition 1.0 2012-04
TECHNICAL
SPECIFICATION
colour
inside
High voltage direct current (HVDC) substation audible noise

IEC/TS 61973:2012(E)
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
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please contact the address below or your local IEC member National Committee for further information.

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International Standards for all electrical, electronic and related technologies.

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IEC/TS 61973 ®
Edition 1.0 2012-04
TECHNICAL
SPECIFICATION
colour
inside
High voltage direct current (HVDC) substation audible noise

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XC
ICS 29.240.10; 29.240.99 ISBN 978-2-8322-0077-3

– 2 – TS 61973 © IEC:2012(E)
CONTENTS
FOREWORD . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
3.1 Sound and noise terms . 10
3.2 Sound radiation terms . 14
3.3 Acoustic fields . 16
4 Environmental influences . 16
4.1 General . 16
4.2 Directivity of sound radiation . 16
4.3 Background noise . 17
4.4 Topography . 19
4.5 Meteorological conditions . 20
5 Noise level limits . 21
5.1 General . 21
5.2 Regulations . 22
5.2.1 Noise level limits . 22
5.2.2 Noise level measurement . 22
5.3 Land-use classifications . 22
5.4 Location of required performance limits . 23
5.4.1 General . 23
5.4.2 At the fence surrounding the HVDC substation or at the border of the
substation owner’s property . 23
5.4.3 At the given contour away from the HVDC substation (e.g. on a circle

perimeter or beyond a property border line) . 23
5.4.4 At the border of a nearby property . 23
5.5 Relationship of performance limits to time duration. 24
5.6 Typical noise performance limits . 24
5.6.1 General . 24
5.6.2 Specific A-weighted sound pressure levels . 24
5.6.3 Maximum allowable increase over background noise levels . 24
6 Sound emitting sources . 25
6.1 General . 25
6.2 Converter transformer . 25
6.2.1 Noise sources in a converter transformer . 25
6.2.2 Comparison with a.c. power transformers . 26
6.2.3 Special features of HVDC converter transformers . 26
6.2.4 Transformer winding noise. 27
6.3 Reactors . 28
6.3.1 Type and design of HVDC reactors . 28
6.3.2 Mechanism of sound generation . 28
6.3.3 AC filter reactors . 33
6.3.4 HVDC smoothing reactors . 34
6.3.5 Self-tuned filter reactors . 35
6.4 Capacitors . 36
6.4.1 Type and design of capacitors . 36

TS 61973 © IEC:2012(E) – 3 –
6.4.2 Mechanism of sound generation . 36
6.5 Cooling fans . 39
6.6 Other sound-emitting sources . 40
6.6.1 Switching devices . 40
6.6.2 Synchronous compensators . 41
6.6.3 Diesel generators . 41
6.6.4 Air conditioning plant . 41
6.6.5 Cooling circuit pumps . 41
6.6.6 Converter valves . 41
6.6.7 Air compressors . 42
6.6.8 Corona sources . 42
6.7 Typical sound power levels of sound emitting sources . 42
7 Sound reduction measures . 42
7.1 General . 42
7.2 Substation layout . 43
7.2.1 General . 43
7.2.2 Transformers and tanked reactors . 43
7.2.3 Air-cored reactors . 43
7.2.4 Capacitors . 44
7.2.5 Cooling fans . 44
7.2.6 Diesel generators . 44
7.2.7 Switching devices . 44
7.2.8 Air conditioning plant . 44
7.2.9 Corona sources . 44
7.2.10 Synchronous compensators . 44
7.3 Component design . 45
7.3.1 General . 45
7.3.2 Transformers and tanked reactors . 45
7.3.3 Air-cored reactors . 45
7.3.4 Capacitors . 45
7.3.5 Cooling fans . 46
7.3.6 Pumps and diesel generators . 46
7.3.7 Switching devices . 46
7.3.8 Air-conditioning plant . 46
7.3.9 High voltage connections . 46
7.4 Sound enclosures . 46
7.4.1 General . 46
7.4.2 Transformers and tanked-reactors . 46
7.4.3 Air-cored reactors . 47
7.4.4 Capacitors . 47
7.5 Retrofitable techniques . 48
7.5.1 Enclosures . 48
7.5.2 Damping . 48
7.5.3 Active noise and vibration mitigation . 48
8 Operating conditions . 48
8.1 General . 48
8.2 Normal operating conditions . 49
8.3 Exceptional operating conditions . 50
8.4 Operating conditions specified for verification. 51

– 4 – TS 61973 © IEC:2012(E)
9 Sound level prediction . 51
9.1 General . 51
9.2 Modelling of plant . 52
9.2.1 General . 52
9.2.2 Layout . 52
9.2.3 Source .
...

IEC TS 61973 ®
Edition 1.1 2019-05
CONSOLIDATED VERSION
TECHNICAL
SPECIFICATION
colour
inside
High voltage direct current (HVDC) substation audible noise
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
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.

need further assistance, please contact the Customer Service

Centre: [e-mail].
IEC TS 61973 ®
Edition 1.1 2019-05
CONSOLIDATED VERSION
TECHNICAL
SPECIFICATION
colour
inside
High voltage direct current (HVDC) substation audible noise

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.10; 29.240.99 ISBN 978-2-8322-6930-5

IEC TS 61973 ®
Edition 1.1 2019-05
CONSOLIDATED VERSION
REDLINE VERSION
colour
inside
High voltage direct current (HVDC) substation audible noise

– 2 – IEC TS 61973:2012+AMD1:2019 CSV
© IEC 2019
CONTENTS
FOREWORD . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
3.1 Sound and noise terms . 10
3.2 Sound radiation terms . 14
3.3 Acoustic fields . 16
4 Environmental influences . 16
4.1 General . 16
4.2 Directivity of sound radiation . 16
4.3 Background noise . 18
4.4 Topography . 20
4.5 Meteorological conditions . 20
5 Noise level limits . 22
5.1 General . 22
5.2 Regulations . 22
5.2.1 Noise level limits . 22
5.2.2 Noise level measurement . 23
5.3 Land-use classifications . 23
5.4 Location of required performance limits . 23
5.4.1 General . 23
5.4.2 At the fence surrounding the HVDC substation or at the border of the
substation owner’s property . 24
5.4.3 At the given contour away from the HVDC substation (e.g. on a circle
perimeter or beyond a property border line) . 24
5.4.4 At the border of a nearby property . 24
5.5 Relationship of performance limits to time duration. 24
5.6 Typical noise performance limits . 25
5.6.1 General . 25
5.6.2 Specific A-weighted sound pressure levels . 25
5.6.3 Maximum allowable increase over background noise levels . 25
6 Sound emitting sources . 25
6.1 General . 25
6.2 Converter transformer . 26
6.2.1 Noise sources in a converter transformer . 26
6.2.2 Comparison with a.c. power transformers . 26
6.2.3 Special features of HVDC converter transformers . 27
6.2.4 Transformer winding noise. 28
6.3 Reactors . 29
6.3.1 Type and design of HVDC reactors . 29
6.3.2 Mechanism of sound generation . 30
6.3.3 AC filter reactors . 34
6.3.4 HVDC smoothing reactors . 35
6.3.5 Self-tuned filter reactors . 36
6.4 Capacitors . 37
6.4.1 Type and design of capacitors . 37

© IEC 2019
6.4.2 Mechanism of sound generation . 37
6.5 Cooling fans . 40
6.6 Other sound-emitting sources . 41
6.6.1 Switching devices . 41
6.6.2 Synchronous compensators . 42
6.6.3 Diesel generators . 42
6.6.4 Air conditioning plant . 42
6.6.5 Cooling circuit pumps . 42
6.6.6 Converter valves . 42
6.6.7 Air compressors . 43
6.6.8 Corona sources . 43
6.7 Typical sound power levels of sound emitting sources . 43
7 Sound reduction measures . 43
7.1 General . 43
7.2 Substation layout . 44
7.2.1 General . 44
7.2.2 Transformers and tanked reactors . 44
7.2.3 Air-cored reactors . 45
7.2.4 Capacitors . 45
7.2.5 Cooling fans . 45
7.2.6 Diesel generators . 45
7.2.7 Switching devices . 45
7.2.8 Air conditioning plant . 45
7.2.9 Corona sources . 45
7.2.10 Synchronous compensators . 46
7.3 Component design . 46
7.3.1 General . 46
7.3.2 Transformers and tanked reactors . 46
7.3.3 Air-cored reactors . 46
7.3.4 Capacitors . 46
7.3.5 Cooling fans . 47
7.3.6 Pumps and diesel generators . 47
7.3.7 Switching devices . 47
7.3.8 Air-conditioning plant . 47
7.3.9 High voltage connections . 47
7.4 Sound enclosures . 47
7.4.1 General . 47
7.4.2 Transformers and tanked-reactors . 48
7.4.3 Air-cored reactors . 48
7.4.4 Capacitors . 48
7.5 Retrofitable techniques . 49
7.5.1 Enclosures . 49
7.5.2 Damping . 49
7.5.3 Active noise and vibration mitigation . 49
8 Operating conditions . 49
8.1 General . 49
8.2 Normal operating conditions . 51
8.3 Exceptional operating conditions . 51
8.4 Operating conditions specified for verification. 52

– 4 – IEC TS 61973:2012+AMD1:2019 CSV
© IEC 2019
9 Sound level prediction .
...