1、BSI Standards Publication Guidance on the interpretation of carbon dioxide and 2-furfuraldehyde as markers of paper thermal degradation in insulating mineral oil PD IEC/TR 62874:2015National foreword This Published Document is the UK implementation of IEC/TR 62874:2015. The UK participation in its p
2、reparation was entrusted to Technical Committee GEL/10, Fluids for electrotechnical applications. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are resp
3、onsible for its correct application. The British Standards Institution 2015. Published by BSI Standards Limited 2015 ISBN 978 0 580 83123 2 ICS 29.040.10 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document was published under the authority of the
4、 Standards Policy and Strategy Committee on 31 May 2015. Amendments/corrigenda issued since publication Date Text affected PUBLISHED DOCUMENT PD IEC/TR 62874:2015 IEC TR 62874 Edition 1.0 2015-05 TECHNICAL REPORT Guidance on the interpretation of carbon dioxide and 2-furfuraldehyde as markers of pap
5、er thermal degradation 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:
6、2015 2 IEC TR 62874:2015 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
7、 ageing in insulating 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 1
8、2 3.7 Maintenance operations 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 Compl
9、ementary monitoring 14 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) Typic
10、al values tables . 19 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: LVD
11、C units 21 PD IEC/TR 62874:2015IEC 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 .
12、22 A.3.6 Family: LVDC 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 th
13、e estimation of paper 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 unit
14、s) . 19 Table A.3 2-FAL 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 (base
15、d on a population of 7 107 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 uninh
16、ibited mineral oil (based 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 CO 2typical values for GSU and excitation transformers, filled with uninhibited mineral oil (base
17、d on a population of 1 098 units) . 21 Table A.9 CO 2typical values for network transmission transformers, filled with uninhibited mineral oil (based on a population of 435 units) 21 Table A.10 CO 2typical values for large distribution transformers, filled with uninhibited mineral oil (based on a po
18、pulation of 7 291 units) . 22 Table A.11 CO 2typical values for industrial distribution transformers, filled with uninhibited mineral oil (based on a population of 4 556 units) . 22 Table A.12 CO 2typical values for LVDC transformers, filled with uninhibited mineral oil (based on a population of 273
19、 units) 22 PD IEC/TR 62874:2015 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 (
20、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 addit
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31、ta of a different kind from 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 f
32、ollowing documents: Enquiry 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
33、accordance with the ISO/IEC 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 wil
34、l be reconfirmed, withdrawn, 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 t
35、hermal degradation during their 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 Te
36、chnical Report), cellulose forms 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 ele
37、ctrical apparata in service. 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 Tec
38、hnical Report is based on the 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
39、 final report of CIGRE WG D1.01.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
40、 applied within this Technical 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
41、 into an IEC standard. Health 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
42、limitations prior to use. The 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 shou
43、ld be carried out and medical 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 us
44、ed sample containers. The disposal 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 th
45、e Bibliography PD IEC/TR 62874:2015IEC 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 t
46、hermal life of transformers cellulosic 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
47、 information on the estimated 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 th
48、e estimation of paper thermal 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 g
49、uide, but they should not be 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 descri
