Rotating electrical machines - Part 27-1: Off-line partial discharge measurements on the winding insulation

This part of IEC 60034 provides a common basis for: - measuring techniques and instruments; - the arrangement of test circuits; - normalization and testing procedures; - noise reduction; - the documentation of test results; - the interpretation of test results, with respect to partial discharge off-line measurements on the winding insulation of rotating electrical machines. The measurement methods described in this document are applicable to stator windings of machines with or without conductive slot coating and to the stator windings of machines made with form wound or random wound windings. In special cases like high voltage rotor field windings, this document is applicable as well. The measurement methods are applicable when testing with alternating sinusoidal voltages from 0,1 Hz up to 400 Hz. Interpretation guidelines are given in this document and are applicable only if all the following requirements are fulfilled: - Measurements performed with power frequency of 50 Hz or 60 Hz, or when testing with power supply within a frequency range of 45 Hz to 65 Hz. - Form wound windings and winding components such as bars and coils. - Winding with conductive slot coating. This is usually valid for machines with voltage rating of 6 kV and higher. For machines with random wound windings, form-wound windings without conductive slot coating, and testing at frequencies differing from power frequencies, the interpretation guidelines are not applicable. The testing procedures for off-line PD-measurements of this document can be used for assessing the uniform quality of manufacturing or/and the trending of these kind of windings as well as converter driven machine windings. NOTE Testing of low voltage machines with so called Type I insulation systems is defined in reference [10]1. Testing procedures for qualification of converter driven high voltage machines with so called Type II insulation systems are dealt with in IEC 60034-18-42 (in addition to the optional electric tests described therein).

Drehende elektrische Maschinen - Teil 27-1: Off-line Teilentladungsmessungen an Ständerwicklungsisolierungen drehender elektrischer Maschinen

Machines électriques tournantes - Partie 27-1: Mesurages à l’arrêt des décharges partielles effectués sur le système d'isolation des enroulements

La présente partie de l’IEC 60034 présente des modalités communes concernant: - les techniques et les appareils de mesure; - la mise en place des circuits d'essai; - les procédures de normalisation et d'essai; - la réduction du bruit; - la documentation des résultats des essais; - l'interprétation des résultats des essais; pour les besoins des mesurages à l’arrêt des décharges partielles dans les systèmes d'isolation des enroulements des machines électriques tournantes. Les méthodes de mesure décrites dans le présent document s’appliquent aux enroulements statoriques des machines avec ou sans revêtement d'encoches conducteur et aux enroulements statoriques des machines constitués avec des enroulements préformés ou des enroulements en vrac. Le présent document s’applique également dans des cas particuliers tels que des enroulements d’excitation rotorique haute tension. Les méthodes de mesure s’appliquent pour des essais effectués avec des tensions sinusoïdales alternatives comprises entre 0,1 Hz et 400 Hz. Le présent document fournit des lignes directrices d'interprétation qui s’appliquent uniquement si toutes les exigences suivantes sont satisfaites: - Mesurages effectués avec une fréquence industrielle de 50 Hz ou 60 Hz, ou lorsque les essais sont effectués avec une source d’alimentation comprise dans une plage de fréquences de 45 Hz à 65 Hz. - Enroulements préformés et composants d’enroulement tels que des barres et des bobines. - Enroulement avec un revêtement d'encoches conducteur. Ces exigences sont généralement valables pour les machines dont la tension assignée est supérieure ou égale à 6 kV. Les lignes directrices d'interprétation ne s’appliquent pas aux machines avec enroulements en vrac et enroulements préformés sans revêtement d'encoches conducteur. Elles ne s’appliquent pas non plus aux essais effectués à des fréquences différentes des fréquences industrielles. Les procédures d’essai applicables aux mesurages à l’arrêt des DP spécifiés dans le présent document peuvent être utilisées pour évaluer la qualité uniforme de fabrication et/ou l’évolution de ces types d’enroulements, ainsi que les enroulements de machines entraînées par convertisseur. NOTE L’essai des machines basse tension avec le système d’isolation appelé système de type 1 est défini à la référence [10]1. L’IEC 60034-18-42 traite des procédures d’essai de qualification des machines haute tension entraînées par convertisseur avec des systèmes d'isolation appelés systèmes de type II (outre les essais électriques facultatifs qui y sont décrits).

Električni rotacijski stroji - 27-1. del: Meritve delne praznitve izolacije statorskega navitja odklopljenih električnih rotacijskih strojev (IEC 60034-27-1:2017)

Ta del standarda IEC 60034 podaja skupno podlago za:
– merilne tehnike in instrumente;
– razporeditev preskusnih tokokrogov;
– postopke normalizacije in preskušanja;
– zmanjšanje hrupa;
– beleženje rezultatov preskusov;
– tolmačenje rezultatov preskusov
v povezavi z meritvami delne praznitve izolacije navitja odklopljenih električnih rotacijskih strojev.
Merilne metode, opisane v tem dokumentu, se uporabljajo za statorska navitja strojev s prevodno prevleko ali brez nje ter statorska navitja strojev, izdelanih iz predhodno oblikovanih ali naključnih navitij. Ta dokument se uporablja tudi v posebnih primerih, npr. za visokonapetostna rotorska navitja. Merilne metode se uporabljajo pri preskušanju z izmeničnimi sinusoidnimi napetostmi od 0,1 Hz do vključno 400 Hz.
V tem dokumentu so podane razlagalne smernice, ki se uporabljajo samo, če so izpolnjene naslednje zahteve:
– Meritve, izvedene z omrežno frekvenco 50 Hz ali 60 Hz, oziroma pri preskušanju z napajanjem v frekvenčnem območju med 45 Hz in 65 Hz.
– Predhodno oblikovana navitja in ovojne komponente, kot so palice in tuljave.
– Navitje s prevodno prevleko. To običajno velja za stroje z nazivno napetostjo, višjo od 6 kV.
Razlagalne smernice se ne uporabljajo za stroje z naključnimi navitji, stroje s predhodno oblikovanimi navitji brez prevodne prevleke in preskušanje pri frekvencah, ki se razlikujejo od omrežnih frekvenc. Preskusne postopke za meritve delne praznitve odklopljenih strojev v tem dokumentu je mogoče uporabljati za ocenjevanje enotne kakovosti proizvodnje in/ali določanje trendov teh vrst navitij ter navitij strojev, ki jih poganjajo pretvorniki.
OPOMBA: Preskušanje nizkonapetostnih strojev s t. i. izolacijskimi sistemi tipa I je opredeljeno v sklicu [10]1.
Preskusni postopki za vrednotenje visokonapetostnih strojev, ki jih poganjajo pretvorniki, s t. i. izolacijskimi sistemi tipa II so obravnavani v standardu IEC 60034-18-42 (skupaj z opisi izbirnih električnih preskusov).

General Information

Status
Published
Publication Date
28-Jun-2018
Technical Committee
Drafting Committee
Current Stage
6060 - Document made available
Due Date
30-Jul-2018

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SLOVENSKI STANDARD
SIST EN IEC 60034-27-1:2018
01-oktober-2018
Nadomešča:
SIST-TS CLC/TS 60034-27:2011

Električni rotacijski stroji - 27-1. del: Meritve delne praznitve izolacije statorskega

navitja odklopljenih električnih rotacijskih strojev (IEC 60034-27-1:2017)

Rotating electrical machines - Part 27-1: Off-line partial discharge measurements on the

stator winding insulation of rotating electrical machines (IEC 60034-27-1:2017)
Drehende elektrische Maschinen - Teil 27-1: Off-line Teilentladungsmessungen an

Ständerwicklungsisolierungen drehender elektrischer Maschinen (IEC 60034-27-1:2017)

Machines électriques tournantes - Partie 27-1: Mesures à l'arrêt des décharges partielles

effectuées sur le système d'isolation des enroulements statoriques des machines
électriques tournantes (IEC 60034-27-1:2017)
Ta slovenski standard je istoveten z: EN IEC 60034-27-1:2018
ICS:
29.160.01 Rotacijski stroji na splošno Rotating machinery in
general
SIST EN IEC 60034-27-1:2018 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN IEC 60034-27-1:2018
---------------------- Page: 2 ----------------------
SIST EN IEC 60034-27-1:2018
EUROPEAN STANDARD EN IEC 60034-27-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2018
ICS 29.160.01 Supersedes CLC/TS 60034-27:2011
English Version
Rotating electrical machines - Part 27-1: Off-line partial
discharge measurements on the stator winding insulation of
rotating electrical machines
(IEC 60034-27-1:2017)

Machines électriques tournantes - Partie 27-1: Mesures à Drehende elektrische Maschinen - Teil 27-1: Off-line

l'arrêt des décharges partielles effectuées sur le système Teilentladungsmessungen an Ständerwicklungsisolierungen

d'isolation des enroulements statoriques des machines drehender elektrischer Maschinen

électriques tournantes (IEC 60034-27-1:2017)
(IEC 60034-27-1:2017)

This European Standard was approved by CENELEC on 2018-01-17. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,

Switzerland, Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 60034-27-1:2018 E
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SIST EN IEC 60034-27-1:2018
EN IEC 60034-27-1:2018
European foreword

The text of document 2/1877/FDIS, future edition 1 of IEC 60034-27-1:2017, prepared by IEC/TC 2

"Rotating machinery" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC

as EN IEC 60034-27-1:2018.
The following dates are fixed:
(dop) 2018-12-29
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2021-06-29
standards conflicting with the
document have to be withdrawn
This document supersedes CEN/TS 60034-27:2011.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice

The text of the International Standard IEC 60034-27-1:2017 was approved by CENELEC as a

European Standard without any modification.

In the official version, for Bibliography, the following note has to be added for the standard indicated:

IEC 60034-18-41 NOTE Harmonized as EN 60034-18-41 (not modified).
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SIST EN IEC 60034-27-1:2018
EN IEC 60034-27-1:2018
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments)

applies.

NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:

www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60034-18-32 - Rotating electrical machines -- Part 18-32: EN 60034-18-32 -
Functional evaluation of insulation systems
- Test procedures for form-wound windings
- Evaluation of electrical endurance
IEC 60034-18-42 - Rotating electrical machines - Part 18-42: EN 60034-18-42 -
Partial discharge resistant electrical
insulation systems (Type II) used in
rotating electrical machines fed from
voltage converters - Qualification tests
IEC 60034-27-4 - Rotating electrical machines - Part 27-4: EN IEC 60034-27-4 -
Measurement of insulation resistance and
polarization index of winding insulation of
rotating electrical machines
IEC 60060-1 - High-voltage test techniques - Part 1: EN 60060-1 -
General definitions and test requirements
IEC 60060-2 - High-voltage test techniques - Part 2: EN 60060-2 -
Measuring systems
IEC 60270 2000 High-voltage test techniques - Partial EN 60270 2001
discharge measurements
+ A1 2015 + A1 2016
IEC/TS 60034-27-2 - Rotating electrical machines - Part 27-2: - -
On-line partial discharge measurements on
the stator winding insulation of rotating
electrical machines
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SIST EN IEC 60034-27-1:2018
---------------------- Page: 6 ----------------------
SIST EN IEC 60034-27-1:2018
IEC 60034-27-1
Edition 1.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Rotating electrical machines –
Part 27-1: Off-line partial discharge measurements on the winding insulation
Machines électriques tournantes –
Partie 27-1: Mesurages à l’arrêt des décharges partielles effectués sur le
système d'isolation des enroulements
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.160.01 ISBN 978-2-8322-5104-1

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN IEC 60034-27-1:2018
– 2 – IEC 60034-27-1:2017 © IEC 2017
CONTENTS

FOREWORD ........................................................................................................................... 5

INTRODUCTION ..................................................................................................................... 7

1 Scope .............................................................................................................................. 9

2 Normative references ...................................................................................................... 9

3 Terms and definitions .................................................................................................... 10

4 Nature of PD in rotating machines ................................................................................. 12

4.1 Basics of PD ......................................................................................................... 12

4.2 Types of PD in rotating machines .......................................................................... 13

4.2.1 General ......................................................................................................... 13

4.2.2 Internal discharges ........................................................................................ 13

4.2.3 Slot discharges .............................................................................................. 13

4.2.4 End-winding gap and surface discharges ....................................................... 14

4.2.5 Foreign conductive materials discharges ....................................................... 14

4.3 Pulse propagation in windings ............................................................................... 14

5 Measuring technologies and instrumentation ................................................................. 15

5.1 General ................................................................................................................. 15

5.2 Influence of frequency response of measuring system .......................................... 15

5.3 Effects of PD coupling units .................................................................................. 16

5.4 Effect of the measuring instrument ........................................................................ 17

6 Visualization of measurements ...................................................................................... 17

6.1 General ................................................................................................................. 17

6.2 Minimum scope of PD data presentation ............................................................... 17

6.3 Additional means of PD data representation.......................................................... 18

6.3.1 General ......................................................................................................... 18

6.3.2 Partial discharge pattern ................................................................................ 19

7 Test circuits ................................................................................................................... 19

7.1 General ................................................................................................................. 19

7.2 Individual winding components.............................................................................. 20

7.3 Complete windings ................................................................................................ 21

7.3.1 General ......................................................................................................... 21

7.3.2 Standard measurements (SX.X) ..................................................................... 22

7.3.3 Optional, extended measurements (EX.X) ..................................................... 23

7.3.4 Using integrated test equipment (IX.X) .......................................................... 24

8 Normalization of measurements ..................................................................................... 25

8.1 General ................................................................................................................. 25

8.2 Individual winding components.............................................................................. 26

8.3 Complete windings ................................................................................................ 26

9 Test procedures ............................................................................................................ 28

9.1 Acquiring PD measurements on windings and winding components ...................... 28

9.1.1 General ......................................................................................................... 28

9.1.2 Test equipment and safety requirements ....................................................... 28

9.1.3 Preparation of test objects ............................................................................. 28

9.1.4 Conditioning .................................................................................................. 29

9.1.5 Test voltages ................................................................................................. 29

9.1.6 PD test procedure .......................................................................................... 30

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SIST EN IEC 60034-27-1:2018
IEC 60034-27-1:2017 © IEC 2017 – 3 –

9.2 Identifying and locating the source of partial discharges ....................................... 32

10 Interpretation of test results ........................................................................................... 32

10.1 General ................................................................................................................. 32

10.2 Interpretation of PD magnitude, inception and extinction voltage........................... 33

10.2.1 Basic interpretation ........................................................................................ 33

10.2.2 Trend in PD in a machine over time ............................................................... 34

10.2.3 Comparisons between winding components or between windings .................. 34

10.3 PD pattern recognition .......................................................................................... 35

10.3.1 General ......................................................................................................... 35

10.3.2 Basic interpretation ........................................................................................ 35

11 Test report ..................................................................................................................... 37

Annex A (informative) Influence parameters of test frequency to testing procedure .............. 39

Annex B (informative) Alternative methods to determine discharge magnitudes ................... 40

B.1 Q , according to definition 3.14 ............................................................................ 40

B.2 Cumulative repetitive PD magnitude Q ................................................................. 41

Annex C (informative) Other off-line methods for PD detection and methods for

localization ........................................................................................................................... 43

Annex D (informative) External noise, disturbance and sensitivity ........................................ 44

D.1 General ................................................................................................................. 44

D.2 Sensitivity ............................................................................................................. 44

D.3 Noise and signal-to-noise ratio .............................................................................. 46

D.4 Disturbances ......................................................................................................... 46

Annex E (informative) Methods of disturbance suppression ................................................. 47

E.1 Frequency range limiting ....................................................................................... 47

E.2 Phase window masking ......................................................................................... 47

E.3 Masking by noise signal triggering ........................................................................ 47

E.4 Noise signal detection by measuring the propagation time .................................... 47

E.5 Two-channel signal difference method .................................................................. 48

E.6 Suppression of constant wave (CW) signals by digital filtering .............................. 49

E.7 Noise and disturbance rejection using signal processing techniques ..................... 49

Annex F (informative) Interpretation of PD magnitude data and phase resolved PD

patterns ................................................................................................................................ 52

F.1 Instructions for interpretation of PRPD patterns .................................................... 52

F.1.1 Example of PRPD patterns ............................................................................ 52

F.1.2 Relative severity of different PD mechanisms ................................................ 54

F.1.3 Interpretation of the PD measurements from the line side and from the

star point ....................................................................................................... 55

F.1.4 Inductive discharges / Vibration sparking ....................................................... 55

Annex G (informative) Test circuits for complete windings ................................................... 57

G.1 General ................................................................................................................. 57

G.2 Schemes and illustrations (see Figure G.1) ........................................................... 57

Annex H (informative) Wide-band and narrow-band measuring systems .............................. 62

H.1 General ................................................................................................................. 62

H.2 Wide band systems ............................................................................................... 63

H.3 Narrow band systems ........................................................................................... 63

Bibliography .......................................................................................................................... 64

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SIST EN IEC 60034-27-1:2018
– 4 – IEC 60034-27-1:2017 © IEC 2017
Figure 1 – Frequency response of a PD pulse and coupling units of various time

constants .............................................................................................................................. 16

Figure 2 – PD magnitude as a function of the normalized test voltage Q=f(U/U ) ............. 18

max

Figure 3 – Example of a PRPD pattern.................................................................................. 19

Figure 4 – Basic test circuits in accordance with IEC 60270 .................................................. 21

Figure 5 – Test circuit for PD measurement (S1.1) on complete windings ............................. 22

Figure 6 – Normalization of the test circuit for measurement S1.1 ......................................... 27

Figure 7 – Test voltage applied to the test object during PD measurement............................ 30

Figure 8 – Example for identification and localization of PD sources ..................................... 36

Figure B.1 – Example for the indication of polarity effect ....................................................... 40

Figure B.2 – Effect of A/D conversion accuracy and the calculation of Q , Example ............. 42

Figure D.1 – Recharging of the test object by various current components ............................ 45

Figure E.1 – Without window masking ................................................................................... 47

Figure E.2 – With window masking ........................................................................................ 47

Figure E.3 – Pulse currents through the measuring circuit .................................................... 48

Figure E.4 – Example of noise rejection ................................................................................ 50

Figure E.5 – Example of cross-talk rejection ......................................................................... 51

Figure F.1 – Example of PRPD patterns ................................................................................ 53

Figure G.1 – Illustrated diagrams for Ү- and Δ-connections, according to 7.3 ........................ 61

Figure H.1 – Typical pulse responses of wide band and narrow band PD systems ................ 62

Table 1 – Connection configuration S1 for open star point .................................................... 22

Table 2 – Connection configuration S2 for closed star point .................................................. 23

Table 3 – Connection configuration E1 for open star point .................................................... 23

Table 4 – Connection configuration E2 for closed star point .................................................. 24

Table 5 – Connection configuration I1 for integrated equipment and open star point,

measurement on high voltage side ........................................................................................ 24

Table 6 – Connection configuration I2 for integrated equipment and open star point,

measurement on star point side ............................................................................................ 25

Table 7 – Connection configuration I3 for integrated equipment and closed star point .......... 25

Table A.1 – Recommended minimum measurement time and maximum slew rates ............... 39

Table F.1 – Severity associated with the main PD sources in rotating machines .................. 54

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SIST EN IEC 60034-27-1:2018
IEC 60034-27-1:2017 © IEC 2017 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –
Part 27-1: Off-line partial discharge measurements
on the winding insulation
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

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governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60034-27-1 has been prepared by IEC technical committee 2:

Rotating machinery.

This International Standard cancels and replaces IEC TS 60034-27 (2006). It constitutes a

technical revision.
The main technical changes with regard to IEC TS 60034-27 (2006) are as follows:
• In 1 version the scope was not well defined, and open to a too wide range of
measurement frequencies. That has been corrected.

• In 1 version pulse magnitude was defined in different ways. Now, 2 definitions are given,

one for each method.

• In 1 version the types of PD were erroneous. Especially the definition of the most critical

“slot discharges” has been improved.
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SIST EN IEC 60034-27-1:2018
– 6 – IEC 60034-27-1:2017 © IEC 2017
• Adding one more common test arrangement to Clause 7.
• Adding Annex A.
• Adding Annex B.
• Adding Annex G.

• Moving part of the original text (valid for old fashioned instruments) to new Annex H.

The text of this International Standard is based on the following documents:
FDIS Report on voting
2/1877/FDIS 2/1887/RVD

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 60034 series, published under the general title Rotating electrical

machines, can be found on the IEC website.

NOTE A table of cross-references of all IEC TC 2 publications can be found in the IEC TC 2 dashboard on the

IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document 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 document using a

colour printer.
---------------------- Page: 12 ----------------------
SIST EN IEC 60034-27-1:2018
IEC 60034-27-1:2017 © IEC 2017 – 7 –
INTRODUCTION

For many years, the measurement of partial discharges (PD) has been employed as a means

of assessing the quality of new insulation systems and the condition of aged insulation

systems. It is also considered as a means of detecting localized sources of PD in used

electrical winding insulation arising from operational stresses in service. Compared with other

dielectric tests (e.g. the measurement of dissipation factor or insulation resistance) the

differentiating character of partial discharge measurements allows PD sources within the

insulation system to be detected.

In connection with the servicing and overhaul of rotating machines, the measurement and

analysis of partial discharges can also provide information on:
– presence of ageing effects and potential defects in the insulating system;
– ageing processes;
– further measures and intervals between overhauls.

Although the PD testing of rotating machines has gained widespread acceptance, it has

emerged from several studies that not only are there different methods of measurement in

existence but also the criteria and methods of analysing and finally assessing the measured

data are often different and not comparable. Consequently, there is a need to give some

guidance to those users who are considering the use of PD measurements to assess the

condition of their insulation systems.

Partial discharge testing of stator windings can be divided into two broad groups:

a) off-line measurements, in which the stator winding is isolated from the power system and

a separate power supply is employed to energize the winding;
b) on-line measurements, in which the r
...

SLOVENSKI STANDARD
SIST EN 60034-27-1:2018
01-oktober-2018
1DGRPHãþD
SIST-TS CLC/TS 60034-27:2011

(OHNWULþQLURWDFLMVNLVWURMLGHO0HULWYHGHOQHSUD]QLWYHL]RODFLMHVWDWRUVNHJD

QDYLWMDRGNORSOMHQLKHOHNWULþQLKURWDFLMVNLKVWURMHY ,(&

Rotating electrical machines - Part 27-1: Off-line partial discharge measurements on the

stator winding insulation of rotating electrical machines (IEC 60034-27-1:2017)
Drehende elektrische Maschinen - Teil 27-1: Off-line Teilentladungsmessungen an

Ständerwicklungsisolierungen drehender elektrischer Maschinen (IEC 60034-27-1:2017)

Machines électriques tournantes - Partie 27-1: Mesures à l'arrêt des décharges partielles

effectuées sur le système d'isolation des enroulements statoriques des machines
électriques tournantes (IEC 60034-27-1:2017)
Ta slovenski standard je istoveten z: EN IEC 60034-27-1:2018
ICS:
29.160.01 Rotacijski stroji na splošno Rotating machinery in
general
SIST EN 60034-27-1:2018 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 60034-27-1:2018
---------------------- Page: 2 ----------------------
SIST EN 60034-27-1:2018
EUROPEAN STANDARD EN IEC 60034-27-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2018
ICS 29.160.01 Supersedes CLC/TS 60034-27:2011
English Version
Rotating electrical machines - Part 27-1: Off-line partial
discharge measurements on the stator winding insulation of
rotating electrical machines
(IEC 60034-27-1:2017)

Machines électriques tournantes - Partie 27-1: Mesures à Drehende elektrische Maschinen - Teil 27-1: Off-line

l'arrêt des décharges partielles effectuées sur le système Teilentladungsmessungen an Ständerwicklungsisolierungen

d'isolation des enroulements statoriques des machines drehender elektrischer Maschinen

électriques tournantes (IEC 60034-27-1:2017)
(IEC 60034-27-1:2017)

This European Standard was approved by CENELEC on 2018-01-17. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,

Switzerland, Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 60034-27-1:2018 E
---------------------- Page: 3 ----------------------
SIST EN 60034-27-1:2018
EN IEC 60034-27-1:2018
European foreword

The text of document 2/1877/FDIS, future edition 1 of IEC 60034-27-1:2017, prepared by IEC/TC 2

"Rotating machinery" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC

as EN IEC 60034-27-1:2018.
The following dates are fixed:
(dop) 2018-12-29
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2021-06-29
standards conflicting with the
document have to be withdrawn
This document supersedes CEN/TS 60034-27:2011.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice

The text of the International Standard IEC 60034-27-1:2017 was approved by CENELEC as a

European Standard without any modification.

In the official version, for Bibliography, the following note has to be added for the standard indicated:

IEC 60034-18-41 NOTE Harmonized as EN 60034-18-41 (not modified).
---------------------- Page: 4 ----------------------
SIST EN 60034-27-1:2018
EN IEC 60034-27-1:2018
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments)

applies.

NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:

www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60034-18-32 - Rotating electrical machines -- Part 18-32: EN 60034-18-32 -
Functional evaluation of insulation systems
- Test procedures for form-wound windings
- Evaluation of electrical endurance
IEC 60034-18-42 - Rotating electrical machines - Part 18-42: EN 60034-18-42 -
Partial discharge resistant electrical
insulation systems (Type II) used in
rotating electrical machines fed from
voltage converters - Qualification tests
IEC 60034-27-4 - Rotating electrical machines - Part 27-4: EN IEC 60034-27-4 -
Measurement of insulation resistance and
polarization index of winding insulation of
rotating electrical machines
IEC 60060-1 - High-voltage test techniques - Part 1: EN 60060-1 -
General definitions and test requirements
IEC 60060-2 - High-voltage test techniques - Part 2: EN 60060-2 -
Measuring systems
IEC 60270 2000 High-voltage test techniques - Partial EN 60270 2001
discharge measurements
+ A1 2015 + A1 2016
IEC/TS 60034-27-2 - Rotating electrical machines - Part 27-2: - -
On-line partial discharge measurements on
the stator winding insulation of rotating
electrical machines
---------------------- Page: 5 ----------------------
SIST EN 60034-27-1:2018
---------------------- Page: 6 ----------------------
SIST EN 60034-27-1:2018
IEC 60034-27-1
Edition 1.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Rotating electrical machines –
Part 27-1: Off-line partial discharge measurements on the winding insulation
Machines électriques tournantes –
Partie 27-1: Mesurages à l’arrêt des décharges partielles effectués sur le
système d'isolation des enroulements
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.160.01 ISBN 978-2-8322-5104-1

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN 60034-27-1:2018
– 2 – IEC 60034-27-1:2017 © IEC 2017
CONTENTS

FOREWORD ........................................................................................................................... 5

INTRODUCTION ..................................................................................................................... 7

1 Scope .............................................................................................................................. 9

2 Normative references ...................................................................................................... 9

3 Terms and definitions .................................................................................................... 10

4 Nature of PD in rotating machines ................................................................................. 12

4.1 Basics of PD ......................................................................................................... 12

4.2 Types of PD in rotating machines .......................................................................... 13

4.2.1 General ......................................................................................................... 13

4.2.2 Internal discharges ........................................................................................ 13

4.2.3 Slot discharges .............................................................................................. 13

4.2.4 End-winding gap and surface discharges ....................................................... 14

4.2.5 Foreign conductive materials discharges ....................................................... 14

4.3 Pulse propagation in windings ............................................................................... 14

5 Measuring technologies and instrumentation ................................................................. 15

5.1 General ................................................................................................................. 15

5.2 Influence of frequency response of measuring system .......................................... 15

5.3 Effects of PD coupling units .................................................................................. 16

5.4 Effect of the measuring instrument ........................................................................ 17

6 Visualization of measurements ...................................................................................... 17

6.1 General ................................................................................................................. 17

6.2 Minimum scope of PD data presentation ............................................................... 17

6.3 Additional means of PD data representation.......................................................... 18

6.3.1 General ......................................................................................................... 18

6.3.2 Partial discharge pattern ................................................................................ 19

7 Test circuits ................................................................................................................... 19

7.1 General ................................................................................................................. 19

7.2 Individual winding components.............................................................................. 20

7.3 Complete windings ................................................................................................ 21

7.3.1 General ......................................................................................................... 21

7.3.2 Standard measurements (SX.X) ..................................................................... 22

7.3.3 Optional, extended measurements (EX.X) ..................................................... 23

7.3.4 Using integrated test equipment (IX.X) .......................................................... 24

8 Normalization of measurements ..................................................................................... 25

8.1 General ................................................................................................................. 25

8.2 Individual winding components.............................................................................. 26

8.3 Complete windings ................................................................................................ 26

9 Test procedures ............................................................................................................ 28

9.1 Acquiring PD measurements on windings and winding components ...................... 28

9.1.1 General ......................................................................................................... 28

9.1.2 Test equipment and safety requirements ....................................................... 28

9.1.3 Preparation of test objects ............................................................................. 28

9.1.4 Conditioning .................................................................................................. 29

9.1.5 Test voltages ................................................................................................. 29

9.1.6 PD test procedure .......................................................................................... 30

---------------------- Page: 8 ----------------------
SIST EN 60034-27-1:2018
IEC 60034-27-1:2017 © IEC 2017 – 3 –

9.2 Identifying and locating the source of partial discharges ....................................... 32

10 Interpretation of test results ........................................................................................... 32

10.1 General ................................................................................................................. 32

10.2 Interpretation of PD magnitude, inception and extinction voltage........................... 33

10.2.1 Basic interpretation ........................................................................................ 33

10.2.2 Trend in PD in a machine over time ............................................................... 34

10.2.3 Comparisons between winding components or between windings .................. 34

10.3 PD pattern recognition .......................................................................................... 35

10.3.1 General ......................................................................................................... 35

10.3.2 Basic interpretation ........................................................................................ 35

11 Test report ..................................................................................................................... 37

Annex A (informative) Influence parameters of test frequency to testing procedure .............. 39

Annex B (informative) Alternative methods to determine discharge magnitudes ................... 40

B.1 Q , according to definition 3.14 ............................................................................ 40

B.2 Cumulative repetitive PD magnitude Q ................................................................. 41

Annex C (informative) Other off-line methods for PD detection and methods for

localization ........................................................................................................................... 43

Annex D (informative) External noise, disturbance and sensitivity ........................................ 44

D.1 General ................................................................................................................. 44

D.2 Sensitivity ............................................................................................................. 44

D.3 Noise and signal-to-noise ratio .............................................................................. 46

D.4 Disturbances ......................................................................................................... 46

Annex E (informative) Methods of disturbance suppression ................................................. 47

E.1 Frequency range limiting ....................................................................................... 47

E.2 Phase window masking ......................................................................................... 47

E.3 Masking by noise signal triggering ........................................................................ 47

E.4 Noise signal detection by measuring the propagation time .................................... 47

E.5 Two-channel signal difference method .................................................................. 48

E.6 Suppression of constant wave (CW) signals by digital filtering .............................. 49

E.7 Noise and disturbance rejection using signal processing techniques ..................... 49

Annex F (informative) Interpretation of PD magnitude data and phase resolved PD

patterns ................................................................................................................................ 52

F.1 Instructions for interpretation of PRPD patterns .................................................... 52

F.1.1 Example of PRPD patterns ............................................................................ 52

F.1.2 Relative severity of different PD mechanisms ................................................ 54

F.1.3 Interpretation of the PD measurements from the line side and from the

star point ....................................................................................................... 55

F.1.4 Inductive discharges / Vibration sparking ....................................................... 55

Annex G (informative) Test circuits for complete windings ................................................... 57

G.1 General ................................................................................................................. 57

G.2 Schemes and illustrations (see Figure G.1) ........................................................... 57

Annex H (informative) Wide-band and narrow-band measuring systems .............................. 62

H.1 General ................................................................................................................. 62

H.2 Wide band systems ............................................................................................... 63

H.3 Narrow band systems ........................................................................................... 63

Bibliography .......................................................................................................................... 64

---------------------- Page: 9 ----------------------
SIST EN 60034-27-1:2018
– 4 – IEC 60034-27-1:2017 © IEC 2017
Figure 1 – Frequency response of a PD pulse and coupling units of various time

constants .............................................................................................................................. 16

Figure 2 – PD magnitude as a function of the normalized test voltage Q=f(U/U ) ............. 18

max

Figure 3 – Example of a PRPD pattern.................................................................................. 19

Figure 4 – Basic test circuits in accordance with IEC 60270 .................................................. 21

Figure 5 – Test circuit for PD measurement (S1.1) on complete windings ............................. 22

Figure 6 – Normalization of the test circuit for measurement S1.1 ......................................... 27

Figure 7 – Test voltage applied to the test object during PD measurement............................ 30

Figure 8 – Example for identification and localization of PD sources ..................................... 36

Figure B.1 – Example for the indication of polarity effect ....................................................... 40

Figure B.2 – Effect of A/D conversion accuracy and the calculation of Q , Example ............. 42

Figure D.1 – Recharging of the test object by various current components ............................ 45

Figure E.1 – Without window masking ................................................................................... 47

Figure E.2 – With window masking ........................................................................................ 47

Figure E.3 – Pulse currents through the measuring circuit .................................................... 48

Figure E.4 – Example of noise rejection ................................................................................ 50

Figure E.5 – Example of cross-talk rejection ......................................................................... 51

Figure F.1 – Example of PRPD patterns ................................................................................ 53

Figure G.1 – Illustrated diagrams for Ү- and Δ-connections, according to 7.3 ........................ 61

Figure H.1 – Typical pulse responses of wide band and narrow band PD systems ................ 62

Table 1 – Connection configuration S1 for open star point .................................................... 22

Table 2 – Connection configuration S2 for closed star point .................................................. 23

Table 3 – Connection configuration E1 for open star point .................................................... 23

Table 4 – Connection configuration E2 for closed star point .................................................. 24

Table 5 – Connection configuration I1 for integrated equipment and open star point,

measurement on high voltage side ........................................................................................ 24

Table 6 – Connection configuration I2 for integrated equipment and open star point,

measurement on star point side ............................................................................................ 25

Table 7 – Connection configuration I3 for integrated equipment and closed star point .......... 25

Table A.1 – Recommended minimum measurement time and maximum slew rates ............... 39

Table F.1 – Severity associated with the main PD sources in rotating machines .................. 54

---------------------- Page: 10 ----------------------
SIST EN 60034-27-1:2018
IEC 60034-27-1:2017 © IEC 2017 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –
Part 27-1: Off-line partial discharge measurements
on the winding insulation
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

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with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence

between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60034-27-1 has been prepared by IEC technical committee 2:

Rotating machinery.

This International Standard cancels and replaces IEC TS 60034-27 (2006). It constitutes a

technical revision.
The main technical changes with regard to IEC TS 60034-27 (2006) are as follows:
• In 1 version the scope was not well defined, and open to a too wide range of
measurement frequencies. That has been corrected.

• In 1 version pulse magnitude was defined in different ways. Now, 2 definitions are given,

one for each method.

• In 1 version the types of PD were erroneous. Especially the definition of the most critical

“slot discharges” has been improved.
---------------------- Page: 11 ----------------------
SIST EN 60034-27-1:2018
– 6 – IEC 60034-27-1:2017 © IEC 2017
• Adding one more common test arrangement to Clause 7.
• Adding Annex A.
• Adding Annex B.
• Adding Annex G.

• Moving part of the original text (valid for old fashioned instruments) to new Annex H.

The text of this International Standard is based on the following documents:
FDIS Report on voting
2/1877/FDIS 2/1887/RVD

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 60034 series, published under the general title Rotating electrical

machines, can be found on the IEC website.

NOTE A table of cross-references of all IEC TC 2 publications can be found in the IEC TC 2 dashboard on the

IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document 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 document using a

colour printer.
---------------------- Page: 12 ----------------------
SIST EN 60034-27-1:2018
IEC 60034-27-1:2017 © IEC 2017 – 7 –
INTRODUCTION

For many years, the measurement of partial discharges (PD) has been employed as a means

of assessing the quality of new insulation systems and the condition of aged insulation

systems. It is also considered as a means of detecting localized sources of PD in used

electrical winding insulation arising from operational stresses in service. Compared with other

dielectric tests (e.g. the measurement of dissipation factor or insulation resistance) the

differentiating character of partial discharge measurements allows PD sources within the

insulation system to be detected.

In connection with the servicing and overhaul of rotating machines, the measurement and

analysis of partial discharges can also provide information on:
– presence of ageing effects and potential defects in the insulating system;
– ageing processes;
– further measures and intervals between overhauls.

Although the PD testing of rotating machines has gained widespread acceptance, it has

emerged from several studies that not only are there different methods of measurement in

existence but also the criteria and methods of analysing and finally assessing the measured

data are often different and not comparable. Consequently, there is a need to give some

guidance to those users who are considering the use of PD measurements to assess the

condition of their insulation systems.

Partial discharge testing of stator windings can be divided into two broad groups:

a) off-line measurements, in which the stator winding is isolated from the power system and

a separate power supply is employed to energize the winding;
b) on-line measurements, in which the rotating machine is operating norma
...

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