1、The Institute of Electrical and Electronics Engineers, Inc.345 East 47th Street, New York, NY 10017-2394, USACopyright 1998 by the Institute of Electrical and Electronics Engineers, Inc.All rights reserved. Published 1998. Printed in the United States of America.IEEE is a registered trademark in the
2、 U.S. Patent (978) 750-8400. Permission to photocopy portions of any individual standard foreducational classroom use can also be obtained through the Copyright Clearance Center.Note: Attention is called to the possibility that implementation of this standard may require use of subject mattercovered
3、 by patent rights. By publication of this standard, no position is taken with respect to the existence orvalidity of any patent rights in connection therewith. The IEEE shall not be responsible for identifying patents forwhich a license may be required by an IEEE standard or for conducting inquiries
4、 into the legal validity or scopeof those patents that are brought to its attention.iiiIntroduction(This introduction is not part of IEEE Std 1406-1998, IEEE Trial-Use Guide to the Use of Gas-In-Fluid Analysis for Electric PowerCable Systems.)This trial-use guide is intended for the engineering spec
5、ialist interested in the evaluation and maintenance of uid-lled cable systems including high-pressure uid-lled and gas-lled pipe-type cables and self-contained cablesoperating at low, medium, or high pressure where the pressurizing medium is either a dielectric uid or gas.The use of dissolved gas an
6、alysis (DGA) began in the 1970s and has become an important tool for those who areresponsible for the reliable operation of these cable systems. The technique requires removing a small sample of thepressurizing uid and analyzing the gasses that are present in solution using a gas chromatograph. The
7、results canprovide clues as to the amount of thermal aging that the cable system has experienced and how this aging may beprogressing in time, and also whether there may be problems in the system, especially in the vicinity of cableaccessories such as splices and terminations that might require de-e
8、nergization and repair.The technology parallels the application of DGA to transformers as described in IEEE Std C57.104-1991. Followingan historical background discussion, the fundamentals of gas generation in dielectric papers and uids is presented asthe basis for the technology. Sufcient data is p
9、resented so that the user can quantify the correlation of DGA data withthe conditions that may have caused the gas generation.Guidelines for the application of DGA and the methods used for sampling, analysis, and interpretation of the resultsare discussed in detail. Also covered are descriptions of
10、other ancillary tests that can be done on the same samples toprovide additional information as to the state of the cable system, and procedures that can be used to lower thediscussed gas content when system operation may be jeopardized.Finally, a reporting format is suggested, and a database that is
11、 maintained by ICC Working Group 5-28 is described.Suggestions for improvement gained by the use of this guide are welcomed. They should be sent to the IEEE StandardsDepartment.The ICC Working Group 5-28 consisted of the following members:John S. Engelhardt, Chair Richard W. Allen, Jr.Paul BarryThom
12、as G. CampbellJohn H. CooperStanley J. CroallRoger DashnerClaus DoenchRoy FleckensteinMark FlobergS. Michael FotyReza GhafurianMohammed KhajaviSteve KozakW. Graham LawsonMarvin McGeeSven OlundGary A. PolhillRonald J. PonistDavid PurnhagenLarry TangMark TodescoSteven WaldorfJay A. WilliamsShayne Wrig
13、htJoseph T. ZimnochThe following persons were on the balloting committee:Torben AaboT. J. Al-HussainiR. W. AllenTheodore A. BalaskaEarle C. Bascom, IIIM. Thomas BlackDavid T. BogdenKent W. BrownPaul S. CardelloThomas C. ChampionJack E. CherryJohn H. CooperPhilip CoxJohn R. DensleyClaus DoenchGeorge
14、S. EagerJohn S. EngelhardtJames FitzgeraldS. Michael FotyRonald F. FrankRobert B. GearKenneth HancockJack HandRichard A. HartleinivWolfgang B. HaverkampStanley V. HeyerLauri J. HiivalaStanley R. HowellRichard HuberFrank KuchtaJack LaskyGabor LudasiJ. D. MedekAndreas MeierJohn E. Merando, Jr.Daleep C
15、. MohlaJames A. MoranShantanu NandiHarry E. OrtonArthur V. PackGary PolhillRonald J. PonistDennis C. PrattGreg P. RampleyRobert A. ResualiDarrell E. SabatkaCandelario de J. Saldivar-CantuHazairin SamaulahRalph W. SammGilbert L. SmithNagu N. SrinivasOrloff W. StyveJohn TanakaAustin C. TingleySteven P
16、. WaldorfDaniel J. WardRoland H. W. WatkinsJ. A. WilliamsJoseph T. ZimnochThe nal conditions for approval of this trial-use guide were met on 30 April 1998. This trial-use guide wasconditionally approved by the IEEE-SA Standards Board on 19 March 1998, with the following membership:Richard J. Hollem
17、an, Chair Donald N. Heirman, Vice Chair Judith Gorman, Secretary Satish K. AggarwalClyde R. CampJames T. CarloGary R. EngmannHarold E. EpsteinJay Forster*Thomas F. GarrityRuben D. GarzonJames H. GurneyJim D. IsaakLowell G. JohnsonRobert KennellyE. G. Al KienerJoseph L. Koepfinger*Stephen R. LambertJ
18、im LogothetisDonald C. LoughryL. Bruce McClungLouis-Franois PauRonald C. PetersenGerald H. PetersonJohn B. PoseyGary S. RobinsonHans E. WeinrichDonald W. Zipse*Member EmeritusKim BreitfelderIEEE Standards Project EditorvContents1. Overview.11.1 Scope 11.2 Purpose. 12. References.13. Definitions.24.
19、Gases used in this guide 25. Historical background .35.1 The need for gas-in-fluid analysis 35.2 Historical use in transformers 45.3 Historical application to HPFF and SCFF cable systems 55.4 Methodology and refinements for special cases 56. Fundamentals of gas generation in cellulose and dielectric
20、 fluids66.1 Mechanisms of gas generation. 66.2 Rates of gas production for the various mechanisms. 106.3 Determination of gas solubility 126.4 Dissolved gas distribution in bulk fluid . 137. Application of gas analysis to cable systems 157.1 How to apply DGA 157.2 Number of samples and sampling loca
21、tions 167.3 Scheduling sample acquisition. 178. Sampling of fluid or gas from cable systems178.1 Sampling objectives . 178.2 Sampling equipment 188.3 Sources of fluid sample contamination 188.4 Sampling conditions. 198.5 Preparation for sampling 198.6 Sampling procedure using the syringe method 208.
22、7 Packaging and transport of samples. 209. Analysis of fluid or gas samples .219.1 Gas analysis by chromatography using ASTM D3612-96 219.2 Gas analysis by other techniques . 229.3 Appearance and physical tests . 229.4 Dielectric tests 239.5 Chemical tests 2310. Reporting of results.2510.1 Data coll
23、ection . 2510.2 Types of data 2510.3 Method of collection 28vi10.4 Recording format and units 2810.5 Data presentation 2811. Interpretation of results .2811.1 Interpretation of the first round of DGA data 2811.2 Changes in dissolved gas concentrations with time. 3112. Methods for treatment of system
24、s with high gas content3112.1 Treating circulated pipe cable systems 3212.2 Treating static pipe cable systems 3212.3 Treating SCFF cable systems. 3213. The ICC database 3313.1 Database software 3314. Bibliography34Annex A (Informative) DGA Reporting forms.35Copyright 1998 IEEE. All rights reserved.
25、 1IEEE Guide to the Use ofGas-In-Fluid Analysis for ElectricPower Cable Systems1. Overview1.1 ScopeThe scope of this guide is to furnish a basic understanding of the conditions that generate gases in fluid-filledcable systems, to establish a universal method of data collection and retention, to sugg
26、est guidelines for theevaluation of samples, and to recommend methods for treatment of systems with high gas content.1.2 PurposeThis guide is intended to provide users of high-pressure fluid-filled (HPFF) pipe cable systems and self-contained fluid-filled (SCFF) cable systems with the basis to estab
27、lish the use of gas-in-fluid analysis fordiagnostic purposes and as an operating maintenance tool.2. ReferencesThe following documents are relevant to the technology of gas-in-fluid analysis:ASTM D2779-92, Standard Test Method for Estimation of Solubility of Gases in Petroleum Liquids.1ASTM D2780-92
28、, Standard Test Method for Solubility of Fixed Gases in Liquids.ASTM D3612-96, Standard Test Method for Analysis of Gases Dissolved in Electrical Insulating Oil by GasChromatography.ASTM D3613-92, Standard Test Methods of Sampling Electrical Insulating Oils for Gas Analysis andDetermination of Water
29、 Content.IEEE Std C57.104-1991, IEEE Guide for the Interpretation of Gases Generated in Oil-ImmersedTransformers.21ASTM publications are available from the American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, USA.2IEEE publications are available from t
30、he Institute of Electrical and Electronics Engineers, 445 Hoes Lane, P.O. Box 1331, Piscataway, NJ 08855-1331, USA.IEEEStd 1406-1998 IEEE GUIDE TO THE USE OF GAS-IN-FLUID2 Copyright 1998 IEEE. All rights reserved.3. DefinitionsThis clause defines terms used in this guide.3.1 dissolved gas: Implies t
31、hat the gas is dissolved in the dielectric fluid. In solution, these gases lose allsemblance of gaseous matter. There are no gas bubbles in the fluid under normal circumstances, and there islittle tendency for the gases to respond to gravitational forces. Dissolved gases will not accumulate at highp
32、oints, and they generally do not pose any threat to the dielectric function of the fluid.3.2 dissolved gas content: The amount of gas dissolved in the fluid expressed as a percent of, or in parts-per-million relative to, the volume of the fluid, where the volume of the gas is defined as that occupie
33、d bythe gas at a pressure of one atmosphere and temperature of 0 C. Dissolved gas content can refer to a specificgas, the total amount of all gases, or the total amount of combustible gases (TCG) only.3.3 saturation: The amount of a particular gas that can be dissolved in a fluid at a given pressure
34、 andtemperature. The saturation of all gases of interest is linearly proportional to absolute pressure. However, theeffect of temperature varies with the specific gas. Some gases exhibit a decrease in saturation withincreasing temperature while others tend to increase. The variation with temperature
35、 is generally small andcan be neglected when evaluating fluid samples in the lab.4. Gases used in this guideThe gases that are the subject of this guide are listed in Tables 1 and 2 by name and chemical symbol.Throughout this guide they may be referenced by either designation depending on context. W
36、hile someusers include the heavier hydrocarbon gases in their investigations, those listed form the basis of thetechnology at the time of publication of this guide. These lists may be expanded to include more gases infuture revisions of this guide if sufficient data become available. Tables 1 and 2
37、also include the molecularweight (MW) and density at 0 C, one atmosphere for each gas. Table 1Gases of interest for dissolved gas analysis (noncombustible)Type of gas Symbol MWDensity(g/L)Nitrogen N228 1.2507Oxygen 0232 1.4289Carbon dioxide CO244 1.9768Table 2Gases of interest for dissolved gas anal
38、ysis (combustible)Type of gas Symbol MWDensity(g/L)Carbon monoxide CO 28 1.2501Hydrogen H22 0.0898Methane CH416 0.7167Ethane C2H630 1.3567Ethylene C2H428 1.2644Acetylene C2H226 1.1708Copyright 1998 IEEE. All Rights Reserved.3IEEE ANALYSIS FOR ELECTRIC POWER CABLE SYSTEMS Std 1406-19985. Historical b
39、ackground5.1 The need for gas-in-fluid analysisSafety, aesthetics, and the unavailability of lands for rights-of-way have made uid-lled high-voltage cable circuitsthe principal method of delivering electric energy to the major urban centers of North America. The reliable operationof these circuits i
40、s critical to society in general and to utilities for which they represent a major capital investment. Itis important to become aware of potential problems with these cable systems, which may have been overstressed,overheated, contaminated, mechanically damaged, or otherwise operated improperly.Reli
41、able operation requires thorough knowledge of a circuits condition. With the age of existing HPFF pipe and SCFFcables approaching and in some cases exceeding their design life expectancy of 40 years, there is a need for methodsthat can help determine or establish the condition of these cable systems
42、. The methods should identify anddiscriminate between problems of major and minor consequences, be repeatable, be able to localize a problem, berelatively simple to perform, and be inexpensive.As direct observation of the cables condition is basically impossible without de-energizing the circuit and
43、 removingcable for lab evaluation, alternate methods of monitoring the present condition and detecting possible degradation ofcable insulation are needed. Gas-in-uid analysis is the best option currently available to assess the condition of thecables insulation system.Degradation of the cable system
44、s insulation or components beyond that expected during normal aging may be causedby any of the following:Thermal stresses developed at hot spot locations or areas that may have experienced over-temperature for anyreason.Damaged shielding tapes caused by thermal-mechanical bending (TMB) activity, loo
45、se skid wires, excessivepulling forces, or damage prior to installation.Electrical stress concentrations sufcient to generate partial discharges of low intensity at operating voltage.Extreme electrical stress causing intense partial discharges in the dielectric.Gas-in-uid analysis, referred to as di
46、ssolved gas analysis (DGA), facilitates the observation of the by-products of thisdegradation through its environment, the insulating and pressurizing uid. With periodic DGA, changes in the level ofthe by-products of cable degradation may be monitored, thus alerting the user to a potential problem w
47、ith the cablesystem while providing important clues as to the exact nature of the problem.DGA is a nondestructive procedure that requires obtaining samples of only the insulating uid from the cable circuit.It is a precise but relatively simple operation that can be performed on a uid sample taken fr
48、om any available accesspoint. As discussed in Clause 6, the types of gases present in the insulating uid, their concentration, and their rates ofproduction can provide insight into the condition of the cable dielectric and the cable shielding system. Whenperformed in a consistent, systematic way and
49、 supplemented by dielectric, water content, and physical appearancetests carried out on the same sample, DGA allows an evaluation of the condition of the cables internal components andearly detection of potential problems. Since access points are normally installed at cable joints and terminations,problems detected can often be localized. Using standard sampling, analysis, and recording procedures, a currentresult can be compared to previous results to establish trends; and because of its relative simplicity, DGA can beperformed on a routine basi
