prEN IEC 60034-18-1:2020
(Main)Rotating electrical machines - Part 18-1: Functional evaluation of insulation systems - General guidelines
Rotating electrical machines - Part 18-1: Functional evaluation of insulation systems - General guidelines
This part of IEC 60034 deals with the general guidelines for functional evaluation of electrical insulation systems, used or proposed to be used in rotating electrical machines within the scope of IEC 60034-1, in order to qualify them.
Drehende elektrische Maschinen - Teil 18-1: Funktionelle Bewertung von Isoliersystemen - Allgemeine Richtlinien
Machines électriques tournantes - Partie 18-1: Evaluation fonctionnelle des systèmes d'isolation - Principes directeurs généraux
Električni rotacijski stroji - 18-1. del: Funkcijsko ocenjevanje izolacijskih sistemov - Splošne smernice
General Information
RELATIONS
Standards Content (sample)
SLOVENSKI STANDARD
oSIST prEN 60034-18-1:2020
01-november-2020
Električni rotacijski stroji - 18-1. del: Funkcijsko ocenjevanje izolacijskih sistemov
- Splošne smerniceRotating electrical machines - Part 18-1: Functional evaluation of insulation systems -
General guidelinesDrehende elektrische Maschinen - Teil 18-1: Funktionelle Bewertung von
Isoliersystemen - Allgemeine Richtlinien
Machines électriques tournantes - Partie 18-1: Evaluation fonctionnelle des systèmes
d'isolation - Principes directeurs générauxTa slovenski standard je istoveten z: prEN IEC 60034-18-1:2020
ICS:
29.080.30 Izolacijski sistemi Insulation systems
29.160.01 Rotacijski stroji na splošno Rotating machinery in
general
oSIST prEN 60034-18-1:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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2/2015/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60034-18-1 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2020-09-11 2020-12-04
SUPERSEDES DOCUMENTS:
2/1970/CD, 2/1980A/CC
IEC TC 2 : ROTATING MACHINERY
SECRETARIAT: SECRETARY:
United Kingdom Mr Charles Whitlock
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if any, in
this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel votingThe attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft for Vote
(CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.TITLE:
Rotating electrical machines – Part 18-1: Functional evaluation of insulation systems – General guidelines
PROPOSED STABILITY DATE: 2024NOTE FROM TC/SC OFFICERS:
Copyright © 2020 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
permission in writing from IEC.---------------------- Page: 3 ----------------------
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CONTENTS
FOREWORD ........................................................................................................................... 3
INTRODUCTION ..................................................................................................................... 5
1 Scope ............................................................................................................................... 6
2 Normative references ....................................................................................................... 6
3 Terms and definitions ....................................................................................................... 7
3.1 General terms ......................................................................................................... 7
3.2 Terms relating to the objects being tested ............................................................... 8
3.3 Terms relating to factors of influence and ageing factors ......................................... 8
3.4 Terms relating to testing and evaluation .................................................................. 9
4 General aspects of functional evaluation ........................................................................ 10
4.1 Introductory remarks ............................................................................................. 10
4.2 Effects of ageing factors ........................................................................................ 10
4.3 Reference/candidate insulation system .................................................................. 11
4.4 Evaluation of minor component or manufacturing changes .................................... 11
4.5 Functional tests ..................................................................................................... 12
4.6 Acceptance tests ................................................................................................... 12
5 Thermal functional tests ................................................................................................. 13
5.1 General aspects of thermal functional tests ........................................................... 13
5.2 Analysis, reporting and classification ..................................................................... 13
6 Electrical functional tests ................................................................................................ 14
6.1 General aspects of electrical functional tests ......................................................... 14
6.2 Analysis and reporting .......................................................................................... 15
7 Mechanical functional tests............................................................................................. 15
8 Environmental functional tests ........................................................................................ 15
9 Multifactor functional tests .............................................................................................. 16
Bibliography .......................................................................................................................... 17
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IEC CDV 60034-18-1 IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –
Part 18-1: Functional evaluation of insulation systems –
General guidelines
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 interna-
tional co-operation on all questions concerning standardization in the electrical and electronic fields. To this
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tion(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the
subject dealt with may participate in this preparatory work. International, governmental and non-governmental
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tional 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 inter-
ested 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 misinter-
pretation 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 be-
tween 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 ex-
penses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publica-
tions.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 pa-
tent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60034-18-1 has been prepared by IEC technical committee 2:
Rotating machinery.This third edition cancels and replaces the second edition, published in 2010 , and constitutes
a technical revision.This edition includes the following significant technical changes with respect to the previous
edition:– provides general guidelines for functional evaluation of different types of windings as be-
fore but incorporates those changes, which have been introduced for the electrical qualifi-
cation and evaluation of windings which are electrically stressed by converter-supply;
– is now focused on general guidelines with all technical details of procedures and qualifica-
tion principles moved to the subsequent parts;– details additional general aspects of functional evaluation and qualification, particularly
the procedure for comparison between reference and candidate insulation systems, the in-
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troduction of the concept of qualification for different expected lifetimes in service and the
evaluation of minor component or manufacturing changes;The text of this standard is based on IEC 60034-18-1:2010
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
NOTE A list 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 edition will remain unchanged until the
stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data related
to the specific publication. At this date, the publication will be• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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IEC CDV 60034-18-1 IEC 2020 – 5 –
1 INTRODUCTION
2 IEC 60034-18 comprises several parts, dealing with different types of functional evaluation
3 and special kinds of test procedures for insulation systems of rotating electrical machines.
4 IEC 60034-18-1 provides general guidelines for such procedures and qualification principles,
5 whereas the subsequent parts IEC 60034-18-21, IEC 60034-18-31, IEC 60034-18-32,
6 IEC 60034-18-33, IEC 60034-18-34, IEC 60034-18-41 and IEC 60034-18-42 give detailed
7 procedures for the various types of windings. Beyond that, part IEC 60034-18-41 and
8 IEC 60034-18-42 contain special test procedures for electrical evaluation of windings
9 electrically stressed by converter-supply.10 The following standards provide the basis and background for the development of the
11 previous standards:12 IEC 60505 establishes the basis for estimating the ageing of electrical insulation systems
13 under conditions of either electrical, thermal, mechanical, environmental stresses or
14 combinations of these (multifactor stresses). It specifies the general principles and
15 procedures that should be followed defining functional test and evaluation procedures.
16 The IEC 60216 series deals with the determination of thermal endurance properties of single
17 insulating materials. On the assumption, that the Arrhenius equations describe the rate of
18 thermal ageing, test procedures and analyzing instructions for getting characteristic
19 parameters like the “Temperature index” (TI), the “Halving interval” (HIC) and the “Relative
20 thermal endurance index” (RTE) are given. For all these parameters selected properties and
21 accepted end-point-criteria are specified. Consequently, a material may be assigned with
22 more than one temperature index, derived from the measurement of different properties and
23 the use of different end-point criteria.IEC 60085 deals with thermal evaluation of electrical in-
24 sulation materials and in particular insulation systems used in electrical equipment …”. In par-
25 ticular, thermal classes of insulation systems are defined and designations are given, such as
26 130 (B), 155 (F) and 180 (H) for use in rotating machines belonging to IEC 60034-1. In the
27 past, materials for insulation systems were often selected solely on the basis of thermal en-
28 durance of individual materials performed according to the IEC 60216 series. However,
29 IEC 60085 recognizes that such selection may be used only for screening materials prior to
30 further functional evaluation of a new insulation system which is not service-proven. Evalua-
31 tion is performed on the basis of a comparison with a service-proven reference insulation sys-
32 tem. Service experience is the preferred basis for assessing the thermal endurance of an in-
33 sulation system.34 IEC 62539 defines statistical methods to analyse times to breakdown and breakdown voltage
35 data obtained from electrical testing of solid insulation materials, for the purposes of
36 characterization of the system and comparison with other insulation systems. The methods of
37 analysis are described for the Weibull-distribution but other distributions are also presented.
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39 ROTATING ELECTRICAL MACHINES –
41 Part 18-1: Functional evaluation of insulation systems –
42 General guidelines
44 1 Scope
45 This part of IEC 60034 deals with the general guidelines for functional evaluation of electrical
46 insulation systems, used or proposed to be used in rotating electrical machines within the
47 scope of IEC 60034-1, in order to qualify them.48 2 Normative references
49 The following referenced documents are indispensable for the application of this document.
50 For dated references, only the edition cited applies. For undated references, the latest edition
51 of the referenced document (including any amendments) applies.52 IEC 60034-1, Rotating electrical machines – Part 1: Rating and performance
53 IEC 60034-18-21, Rotating electrical machines – Part 18-21: Functional evaluation of insula-
54 tion systems – Test procedures for wire-wound windings – Thermal evaluation and classifica-
55 tion56 IEC 60034-18-31, Rotating electrical machines – Part 18-31: Functional evaluation of insula-
57 tion systems – Test procedures for form-wound windings – Thermal evaluation and classifica-
58 tion of insulation systems used in machines up to and including 50 MVA and 15 kV
59 IEC 60034-18-32, Rotating electrical machines – Part 18-32: Functional evaluation of insula-
60 tion systems – Test procedures for form-wound windings – Evaluation of electrical endurance
61 of insulation systems used in machines up to and including 50 MVA and 15 kV62 IEC 60034-18-33, Rotating electrical machines – Part 18-33: Functional evaluation of insula-
63 tion systems – Test procedures for form-wound windings – Multifactor functional evaluation –
64 Endurance under combined thermal and electrical stresses of insulation systems used in ma-
65 chines up to and including 50 MVA and 15 kV66 IEC 60034-18-34, Rotating electrical machines – Part 18-34: Functional evaluation of insula-
67 tion systems – Test procedures for form-wound windings – Evaluation of thermomechanical
68 endurance of insulation systems69 IEC 60034-18-41 EDITION 1.1, Rotating electrical machines – Part 18-41: Partial discharge free
70 electrical insulation systems (Type I) used in rotating electrical machines fed from voltage converters -
71 Qualification and quality control tests / Combines IEC 60034-18-41 (2014-03) and AMD 1 (2019-06)
72 IEC 60034-18-42, Rotating electrical machines – Part 18-42: Partial discharge resistant electrical
73 insulation systems (Type II) used in rotating electrical machines fed from voltage converters - Qualifica-
74 tion tests IEC 60085, Thermal evaluation and designation of electrical insulation
75 IEC 60216 (all parts), Electrical insulating materials – Properties of thermal endurance
76 IEC 60493-1, Guide for the statistical analysis of ageing test data – Part 1: Methods based on
77 mean values of normally distributed test results78 IEC 60505:2004, Evaluation and qualification of electrical insulation systems
79 IEC 61858-1 (2014-02-01, valid) Electrical insulation systems - Thermal evaluation of
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80 modifications to an established EIS - Part 1: Wire-wound winding EIS
81 IEC 61858-2 (2014-02-01,valid) Electrical insulation systems - Thermal evaluation of
82 modifications to an established EIS - Part 2: Form-wound EIS83 IEC 62539, Guide for the statistical analysis of electrical insulation breakdown data
84 3 Terms and definitions85 For the purposes of this document, the following terms and definitions apply.
86 3.1 General terms
87 3.1.1
88 class temperature
89 temperature for which the insulation system is suitable, as defined by the thermal class in
90 IEC 60085 and as used in IEC 6050591 3.1.2
92 insulation system
93 insulating structure containing one or more electrical insulating materials applied over con-
94 ducting parts employed in rotating electrical machines95 [IEC 60505:2004, 3.1.1, modified]
96 NOTE 1 There may be several insulation components within the windings, each being designed for different
97 stresses in service, i.e. turn insulation, slot insulation and end-winding insulation. Different criteria may be applied
98 to the various components within the overall system.99 NOTE 2 There may be more than one insulation system in a particular type of machine. These insulation systems
100 may have different thermal classes (e.g. stator and rotor windings).101 3.1.3
102 candidate insulation system
103 insulation system being tested to determine its capability with respect to ageing factors
104 [IEC 60050-411, Amendment 1:2007, 411-39-26, modified]105 3.1.4
106 reference insulation system
107 insulation system whose performance has been established by satisfactory service
108 experience109 [IEC 60050-411, Amendment 1:2007, 411-39-27]
110 3.1.5
111 coil
112 one or more turns of insulated conductors connected in series and surrounded by common
113 insulation, arranged to link or produce magnetic flux114 [IEC 60050-411:1996, 411-38-03, modified]
115 3.1.6
116 bar
117 either of two parts which, after placed in their slots and when connected together, will form
118 the complete form-wound coil (see 3.1.8) and which comprise a coil side and an appropriate
119 end winding120 [IEC 60050-411:1996, 411-38-05, modified]
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121 NOTE Large a.c. machines commonly use bars, and usually, though not always, they form single-turn coils in a
122 two-layer winding.123 3.1.7
124 wire-wound winding
125 winding which is wound with one or several insulated conductors and in which the individual
126 conductors occupy random positions in the coil side127 NOTE It is usually random-wound with round conductors.
128 [IEC 60050-411:1996, 411-38-13, modified]
129 3.1.8
130 form-wound winding
131 winding consisting of coils or bars which are preformed to shape, insulated and substantially
132 completed before they are inserted into their final places133 NOTE Coils or bars are usually wound with rectangular conductors.
134 [IEC 60050-411:1996, 411-38-11, modified]
135 3.2 Terms relating to the objects being tested
136 3.2.1
137 test object
138 unit being tested
139 NOTE 1 It may be an actual machine or part thereof or a special test model (see 3.2.3 and 3.2.4) which can be
140 subjected to functional tests.141 NOTE 2 A test object may contain more than one test specimen (see 3.2.2).
142 3.2.2
143 test specimen
144 individual component within a test object which can be used to generate one piece of test da-
145 ta (e.g. time to failure)146 NOTE A test specimen may contain more than one insulation component (e.g. turn insulation and conductor to
147 earth insulation), any one of which can provide that piece of data.148 3.2.3
149 formette
150 special test model used for the evaluation of the insulation systems for form-wound windings
151 [IEC 60050-411, Amendment 1:2007, 411-53-64]152 3.2.4
153 motorette
154 special test model used for the evaluation of the insulation systems for wire-wound (random-
155 wound) windings156 [IEC 60050-411, Amendment 1:2007, 411-53-65]
157 3.3 Terms relating to factors of influence and ageing factors
158 3.3.1
159 factor of influence
160 stress imposed by conditions of operation, environment or test that may affect ageing or life of
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162 3.3.2
163 ageing factor
164 factor of influence that causes ageing
165 NOTE In the winding of an electrical machine, different factors of influence or ageing factors can be dominant in
166 different parts (e.g. turn insulation and end-winding insulation). Therefore, different criteria may be used to assess
167 those parts of the insulation. It can also be appropriate to apply different procedures of functional evaluation to
168 these parts.169 3.4 Terms relating to testing and evaluation
170 3.4.1
171 diagnostic factor
172 variable or fixed stress applied to an insulation component of a test specimen in order to es-
173 tablish its condition after ageing without significantly adding to the ageing
174 [IEC 60505:2004, 3.3.7, modified]175 3.4.2
176 functional test
177 comparative test in which the candidate and the reference insulation systems are exposed to
178 ageing and diagnostic factors in order to qualify the candidate system, or, a functional test
179 may also be related to a diagnostic property, for instance as defined in IEC 60034-18-41, the
180 PD-inception voltage.181 3.4.3
182 endurance test
183 test in which the insulation system of a test object is exposed to one or more ageing factors
184 related to service conditions and where changes in specific properties are evaluated by
185 diagnostic tests186 3.4.4
187 diagnostic test
188 test in which the insulation system of a test object is exposed to one or more diagnostic
189 factors in order to discern its condition through measurements or proof tests and to determine
190 when the end-point criterion has been reached191 3.4.5
192 end-point criterion
193 selected value of a characteristic of a test object indicating the end of its test life or arbitrarily
194 chosen for the purpose of the comparison of insulation systems195 3.4.6
196 end-point
197 end of a test as defined by the end-point criterion
198 3.4.7
199 classification
200 set of actions leading to determination of the thermal class of an insulation system
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202 3.4.8
203 type test
204 It is conducted on first prototype of product to confirm the design specifications, it is usually
205 not repeated on other products of same type.206 3.4.9
207 quality control test
208 are followed in order to ensure that the quality of a product is maintained against a set of
209 benchmarks and that any errors encountered are either eliminated or reduced.210
211 3.4.10
212 routine test
213 A test made on each individual device during or after manufacture to check, if it complies with
214 the requirements of the standard concerned or the criteria specified.215 4 General aspects of functional evaluation
216 4.1 Introductory remarks
217 Most functional tests given in the IEC 60034-18 series are comparative. The performance of a
218 candidate system is compared with that of a reference system when both are subjected to
219 equivalent test conditions with respect to test objects, methods of ageing and diagnostic tests.
220 It is not necessarily required that the reference system is physically to be tested in parallel, if
221 the test results of the reference system used have been documented previously and obtained
222 from same test conditions.223 The reference system normally is particular and real – but its quantified minimum performance
224 can also be defined by an agreed reference lifeline, provided by an IEC-Standard as in
225 60034-18-42.226 At the end of every functional test, the functional evaluation shall be made. This means it is
227 necessary to compare the diagnostic data obtained from the candidate and the reference
228 system, usually to compare the mean times to failure.229 If the data from the candidate system is no worse than from the reference system, the
230 candidate system is considered to be qualified. This is true if the 90 % confidence interval of
231 that percentile of the used probability distribution which represents the mean value falls above
232 or within that obtained from the reference system (see IEC 60493-1 and IEC 62539).
233 The large differences found in rotating electrical machine windings, in terms of size, voltage,
234 operating conditions and expected lifetime-behaviour during service necessitate the use of
235 different procedures for functional evaluation of thermal, electrical and multifactor ageing (se-
236 ries 18-21, -31, -32, -33, -34, -41, -42) to qualify various types of windings. These procedures
237 can be of different complexity, the simplest being based on a single ageing factor (e.g. ther-
238 mal or electrical).239 The procedures for functional evaluation will permit comparisons and allow qualification of
240 candidate insulation systems. However, they cannot completely determine the merits of any
241 particular insulation system. Principally it is not possible to give an operational lifetime fore-
242 cast of the individual winding insulation based on any kind of functional tests. Such
243 information can be obtained in general only from extended service experience.
244 4.2 Effects of ageing factors245 All ageing factors, i.e. thermal, electrical, environmental and mechanical, affect the life of all
246 types of machines but the significance of each factor varies with the type of machine and the
247 expected duty. In some cases, one of these ageing factors is considered to be dominant.
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248 In other cases, several ageing factors may be acting significantly. These different conditions
249 have to be considered in choosing the appropriate functional test according to this standard.
250 Insulation of small or medium low-voltage line-fed machines is degraded primarily by
251 temperature and environment, with electrical and mechanical stresses being of less
252 importance.253 Medium to large machines, using form-wound windings, are also affected by temperature and
254 environment but, in addition, the electrical and mechanical stresses can be important ageing
255 factors.256 Very large machines, which generally utilize form-wound (with bars) windings and which can
257 operate in a special environment such as hydrogen, are normally most affected by mechanical
258 stresses or electrical stresses, or both. Temperature and environment can be less significant
259 ageing factors.260 The winding insulation system of small, medium, large and very large converter fed machines
261 may be substantially electrically stressed (see IEC 60034-18-41 and IEC 60034-18-42).
262 4.3 Reference/candidate insulation system263 An insulation system qualifies to be used as a reference insulation system if its performance
264 has been established by satisfactory service experience. This means:265 – it has shown successful operation over suitably long periods of time at operating
266 conditions characteristic of the rating (or class) and in typic...
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