1、BSI Standards PublicationGuidance on the interpretation of carbon dioxide and 2-furfuraldehyde as markers of paper thermaldegradation in insulating mineral oilPD IEC/TR 62874:2015National forewordThis Published Document is the UK implementation of IEC/TR 62874:2015.The UK participation in its prepar
2、ation was entrusted to TechnicalCommittee GEL/10, Fluids for electrotechnical applications.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions ofa contract. Users are responsible fo
3、r its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 83123 2ICS 29.040.10Compliance with a British Standard cannot confer immunity fromlegal obligations.This Published Document was published under the authority of theStandards Policy
4、 and Strategy Committee on 31 May 2015.Amendments/corrigenda issued since publicationDate Text affectedPUBLISHED DOCUMENTPD IEC/TR 62874:2015IEC TR 62874 Edition 1.0 2015-05 TECHNICAL REPORT Guidance on the interpretation of carbon dioxide and 2-furfuraldehyde as markers of paper thermal degradation
5、 in insulating mineral oil INTERNATIONAL ELECTROTECHNICAL COMMISSION ICS 29.040.10 ISBN 978-2-8322-2661-2 Registered trademark of the International Electrotechnical Commission Warning! Make sure that you obtained this publication from an authorized distributor. PD IEC/TR 62874:2015 2 IEC TR 62874:20
6、15 IEC 2015 CONTENTS FOREWORD . 4 INTRODUCTION . 6 1 Scope 7 2 Normative references 7 3 Significance . 8 3.1 General . 8 3.2 Thermal and mechanical degradation of paper 8 3.2.1 General . 8 3.2.2 Impact of temperature 8 3.2.3 Impact of humidity and oxygen 9 3.3 Symptoms of paper ageing in insulating
7、oil . 10 3.3.1 General . 10 3.3.2 Volatile by-products . 11 3.3.3 Soluble by-products . 11 3.3.4 Insoluble by-products 11 3.4 Operational parameters influencing paper thermal ageing . 11 3.5 Role of oil type and condition 12 3.6 Fault conditions that may affect thermal ageing 12 3.7 Maintenance oper
8、ations that may affect thermal ageing indicators 13 3.7.1 General . 13 3.7.2 Effects of oil reconditioning 13 3.7.3 Effects of oil reclamation . 13 3.7.4 Effects of oil change 13 4 Monitoring protocol 14 4.1 General . 14 4.2 Parameters . 14 4.2.1 Basic monitoring 14 4.2.2 Complementary monitoring 14
9、 4.3 Recommended testing frequencies . 14 5 Typical values of paper ageing symptoms 15 5.1 General . 15 5.2 Families of equipment . 15 6 Estimation of paper thermal degradation and ageing rate 16 6.1 General approach . 16 6.2 Practice 16 7 Actions 17 Annex A (informative) Typical values tables . 19
10、A.1 General warning . 19 A.2 2-FAL typical values . 19 A.2.1 General . 19 A.2.2 Family: GSU (generation step-up units) . 19 A.2.3 Family: network transmission units 20 A.2.4 Family: large distribution units . 20 A.2.5 Family: industrial distribution units . 20 A.2.6 Family: LVDC units 21 PD IEC/TR 6
11、2874:2015IEC TR 62874:2015 IEC 2015 3 A.3 Carbon dioxide typical values 21 A.3.1 General . 21 A.3.2 Family: GSU (generation step-up units) . 21 A.3.3 Family: network transmission units 21 A.3.4 Family: large distribution units . 22 A.3.5 Family: industrial distribution units . 22 A.3.6 Family: LVDC
12、units 22 Bibliography 23 Figure 1 Schematic diagram showing rate of ageing k, depending on different ageing mechanisms 9 Figure 2 Relationship between mechanical properties of insulating paper and paper degree of polymerization (DP) 5. . 10 Figure 3 Example of flow-chart for the estimation of paper
13、degradation conditions 17 Table A.1 2-FAL typical values for GSU transformers, filled with uninhibited mineral oil (based on a population of 1 860 units) 19 Table A.2 2-FAL typical values for GSU transformers, filled with inhibited mineral oil (based on a population of 176 units) . 19 Table A.3 2-FA
14、L typical values for network transmission transformers, filled with uninhibited mineral oil (based on a population of 2 845 units) . 20 Table A.4 2-FAL typical values for large distribution transformers, with open breathing conservator, filled with uninhibited mineral oil (based on a population of 7
15、 107 units) . 20 Table A.5 2-FAL typical values for large distribution transformers, with sealed conservator, filled with uninhibited mineral oil (based on a population of 288 units) . 20 Table A.6 2-FAL typical values for industrial distribution transformers, filled with uninhibited mineral oil (ba
16、sed on a population of 3 885 units) . 20 Table A.7 2-FAL typical values for LVDC transformers, filled with uninhibited mineral oil (based on a population of 360 units) 21 Table A.8 CO2typical values for GSU and excitation transformers, filled with uninhibited mineral oil (based on a population of 1
17、098 units) . 21 Table A.9 CO2typical values for network transmission transformers, filled with uninhibited mineral oil (based on a population of 435 units) 21 Table A.10 CO2typical values for large distribution transformers, filled with uninhibited mineral oil (based on a population of 7 291 units)
18、. 22 Table A.11 CO2typical values for industrial distribution transformers, filled with uninhibited mineral oil (based on a population of 4 556 units) . 22 Table A.12 CO2typical values for LVDC transformers, filled with uninhibited mineral oil (based on a population of 273 units) 22 PD IEC/TR 62874:
19、2015 4 IEC TR 62874:2015 IEC 2015 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ GUIDANCE ON THE INTERPRETATION OF CARBON DIOXIDE AND 2-FURFURALDEHYDE AS MARKERS OF PAPER THERMAL DEGRADATION IN INSULATING MINERAL OIL FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organiz
20、ation 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, IE
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22、h may participate in this preparatory work. International, governmental and non-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 ag
23、reement 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) IE
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25、ed 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 c
26、orresponding 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
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28、 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
29、) 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 rig
30、hts. IEC shall not be held responsible for identifying any or all such patent rights. The main task of IEC technical committees is to prepare International Standards. However, a technical committee may propose the publication of a Technical Report when it has collected data of a different kind from
31、that which is normally published as an International Standard, for example “state of the art“. IEC TR 62874, which is a Technical Report, has been prepared by IEC technical committee 10: Fluids for electrotechnical applications. The text of this standard is based on the following documents: Enquiry
32、draft Report on voting 10/903/DTR 10/917A/RVC Full information on the voting for the approval of this Technical Report can be found in the report on voting indicated in the above table. PD IEC/TR 62874:2015IEC TR 62874:2015 IEC 2015 5 This publication has been drafted in accordance with the ISO/IEC
33、Directives, Part 2. The committee has decided that the contents of this publication will remain unchanged until the stability date indicated on the IEC website under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication will be reconfirmed, withdrawn,
34、 replaced by a revised edition, or amended. A bilingual version of this publication may be issued at a later date. PD IEC/TR 62874:2015 6 IEC TR 62874:2015 IEC 2015 INTRODUCTION The cellulosic solid insulation of transformers and other electrical apparatus is subject to thermal degradation during th
35、eir operational lifetime. This results in a progressive loss of papers mechanical properties, such as tensile strength, which are related to the duration of the technical life of the equipment 3,4 1. During its thermal degradation process (also called “ageing” in this Technical Report), cellulose fo
36、rms several by-products, some of which may be detected by means of insulating oils chemical analysis 1,2. The concentration and rate of increase of those by-products can be used as a tool to estimate the progress of paper thermal degradation in transformers and other electrical apparata in service.
37、For this reason, IEC technical committee 10 has prepared this Technical Report for the monitoring of insulating oil parameters related to cellulose ageing and the interpretation of results, as a guidance to the thermal degradation evaluation of insulating paper. This Technical Report is based on the
38、 evaluation of cellulose ageing by-products content in insulating oil, and their rate of formation during the life of the oil-immersed electrical equipment. Statistical reference values reported in Annex A of this Technical Report are based on data collected by TC10. The final report of CIGRE WG D1.
39、01.TF13 7 was taken as a source of information concerning mechanisms and parameters influencing the formation of furanic compounds. NOTE Methods for the estimation of actual degree of polymerization (DP) values of paper, which are widely available in literature, were not applied within this Technica
40、l Report. This is due to the fact that a number of different models have been developed and reported, and they often lead to different results. Moreover, the applicability of those models has not been sufficiently proven by comparison with field experience to be included into an IEC standard. Health
41、 and safety This Technical Report does not purport to address all the safety problems associated with its use. It is the responsibility of the user of the Technical Report to establish appropriate health and safety practices and determine the applicability of regulatory limitations prior to use. The
42、 mineral oils which are the subject of this Technical Report should be handled with due regard to personal safety and hygiene. Direct contact with eyes may cause slight irritation. In the case of eye contact, irrigation with copious quantities of clean running water should be carried out and medical
43、 advice sought. Some of the tests specified in this Technical Report involve the use of processes that could lead to a hazardous situation. Attention is drawn to the relevant standard for guidance. Environment This Technical Report involves mineral oils, chemicals and used sample containers. The dis
44、posal of these items should be carried out in accordance with current national legislation with regard to the impact on the environment. Every precaution should be taken to prevent the release into the environment of mineral oil. _ 1Figures in square brackets refer to the Bibliography PD IEC/TR 6287
45、4:2015IEC TR 62874:2015 IEC 2015 7 GUIDANCE ON THE INTERPRETATION OF CARBON DIOXIDE AND 2-FURFURALDEHYDE AS MARKERS OF PAPER THERMAL DEGRADATION IN INSULATING MINERAL OIL 1 Scope IEC TR 62874, which is a Technical Report provides guidance for the estimation of consumed thermal life of transformers c
46、ellulosic insulators, through the analysis of some compound dissolved in the insulating mineral oil. A comparison between analytical results of 2-furfural (2-FAL) and carbon oxides and their correspondent typical values estimated for different families of equipment gives information on the estimated
47、 thermal degradation of papers. The ageing rate of insulating papers can be evaluated, in short time ranges (e.g. 1 year), by regularly monitoring 2-FAL and carbon oxides content in the oil and by comparing them to typical rates of increase. A statistical approach for the estimation of paper thermal
48、 degradation, and the evaluation of ageing rate is given. Typical values for concentrations and rates of increase of the parameters related to paper ageing were extrapolated from a statistical database collected, and are reported in Annex A. They may be used as a rough guide, but they should not be
49、considered as threshold values. This Technical Report is only applicable to transformers and reactors filled with insulating mineral oils and insulated with Kraft paper. The approaches and procedures specified should be taken as a practical guidance to investigate the thermal degradation of cellulosic insulation, and not as an algorithm to calculate the actual degree of polymerization (DP) of papers. The paper thermal life evaluation protocol described in this Technical Report
