DOCSLIB.ORG

Dissolved Gas Analysis and Oil Condition Testing

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dissolved Gas Analysis and Oil Condition Testing Product Information Dissolved gas analysis and supervision of oil condition in transformers and reactors Transformers Diagnostic Services at ABB performs dissolved gas analysis and supervision of oil condition in power transformers, reactors, instrument transformers, circuit breakers and oil- insulated cables. This product information is divided into the following sections: 1. Dissolved gas analysis (DGA) 2. Supervision of oil condition 3. Sampling and frequency of analyses 4. Ordering of tests Figure 1. Test vessels. 1. DISSOLVED GAS ANALYSIS (IEC 60599) TCG – total combustible gas content (H2, CH4, C2H4, C2H6, For many years the method of analysing gases dissolved in C2H2, CO, C3H6, C3H8) the oil has been used as a tool in transformer diagnostics in order to detect incipient faults, to supervise suspect trans- All these gases except oxygen and nitrogen may be formed formers, to test a hypothesis or explanation for the prob- during the degradation of the insulation. The amount and the able reasons of failures or disturbances which have already relative distribution of these gases depend on the type and occurred and to ensure that new transformers are healthy. severity of the degradation and stress. Finally, DGA could be used to give scores in a strategic rank- ing of a transformer population used in condition assessments 1.1 Procedure of transformers. The DGA procedure consists of essentially four steps: In this respect the dissolved gas analysis is regarded as a − sampling of oil from the transformer fairly mature technique and it is employed by several ABB − extraction of the gases from the oil transformer companies around the world either in own plant − analysis of the extracted gas mixture in a gas chromatog- or in cooperation with an affiliated or independent laboratory. raphy, GC. − interpretation of the analysis according to an evaluation The idea with dissolved gas analysis is based on the fact that scheme. during its lifetime the transformer generates decomposition gases, essentially from the organic insulation, under the influ- The oil samples should preferably be taken in the moving ence of various stresses, both normal and abnormal. oil so that the gas generated somewhere easily and rapidly is transported from the point of generation to the sampling The gases that are of interest for the DGA analysis are the point. Suitable locations are valves in the cooler/radiator cir- following: cuit. To take samples from these locations is not always pos- sible because of design limitations. Other places from which H2 – hydrogen to draw samples are the cover, bottom valve, the conservator CH4 – methane and from the Buchholz relay. C2H4 – ethylene C2H6 – ethane In addition, it is very important that the sampling is made in C2H2 – acetylene such a way that the contamination of the sampling vessel is C3H6 – propene held at a minimum and that gas are not lost during sampling C3H8 – propane or transportation to the laboratory. CO – carbon monoxide CO2 – carbon dioxide O2 – oxygen N2 – nitrogen The removal of the gases from the oil can be accomplished by − Determination of the gas level, either determined in ppm or ml various methods: gas. − Determination of rates of increase („production rates“), in − partial degassing (single-cycle vacuum extraction) ppm/day or ml gas/day − total degassing (multi-cycle vacuum extraction) − stripping by flushing the oil with another gas. Around the world and during the years several different − by the headspace technique in which gases are ”equalized” schemes have been proposed as evaluation schemes for the between a free gas volume and the oil volume. DGA. The most commonly known schemes are the one pro- posed by Rogers forming the basis for the ANSI method and ABB Transformers Diagnostic Services in Ludvika uses the the scheme laid down in IEC Publication 60599. Both these headspace method (figure 2). methods are using ratios between gas concentrations. After extraction the extracted gas mixture is fed into adsorp- In order to get a feeling for DGA interpretation the ”key-gas tion columns in a GC where the different gases are adsorbed method” is appropriate (figure 3). and separated to various degrees and consequently reaches the detector after different periods of time. One looks for the most prominent gas - the one which differs most from a tacitly expected „normal“ level (or change). For In this way the gas mixture is separated into individual chemi- instance, at overheating of cellulose the main decomposition cal compounds, identified and their concentrations in volume gases are CO and CO2. At a partial discharge of corona H2 gas STP/volume oil is calculated and expressed in ppm. is formed (PD in cellulose involves the formation of carbon ox- (STP=standard temperature and pressure). ides). At a more severe electric discharge such as arcing C2H2 is formed (normally also H2 is formed with smaller amounts of It should be emphasized that this extraction and analysis may methane and ethane. If CO is present cellulose is involved). involve analytical errors which mean that it may be difficult to Finally, at overheated oil it is the hydrocarbons that are formed directly compare the results from two different laboratories. – normally the saturated hydrocarbons such as C2H6 at lower One should not jump from one lab to another but try to stick temperatures and unsaturated such as C2H4 at higher tem- to one well-reputed lab. peratures. Acetylene indicates very high temperatures. 1.2 Interpretation This scheme can also be used to understand the evaluation- There are several different approaches how to explain and schemes based on ratios. interpret the analysed gas composition and to diagnose the condition of the transformer. Essentially the following methods For instance, the IEC method uses three ratios: are at hand: C2H2 CH4 C2H4 − Identification of the key gas. The key gas identifies a parti- C2H4 H2 C2H6 cular problem, e.g. H2 indicate partial discharges (PD). − Determination of ratios between gases, normally between CH4/H2 is used to discriminate between a thermal fault and gas levels. an electric fault. C2H2/C2H4 indicates the presence of a strong discharge or very severe electric problem and C2H4/C2H6 is an indication of the oil temperatures. 1. Overheating of cellulose CO, CO2 2. Overheating of oil increasing temperature C2H6 C2H4 C2H4 CH4 CH4 CH4 C2H2 3. Partial discharges (PD) increasing intensity H2 H2 C2H2 4. Discharges C2H2, H2 Figure 2. Headspace gas chromatography instrument for the analysis Figure 3. Characteristic key-gases, principal layout. of gases in insulation oil. 2 Dissolved gas analysis and supervision of oil condition in transformers and reactors 1.3 Application There are a number of different tests devised for detecting How often one should take oil samples depends on the im- changes in electrical properties and chemical composition of portance of the transformer. the oil. Some are made in order to obtain information about the status of the oil itself, while others are made mainly for − When we suspect a fault (e.g. abnormal sounds). the assessment of the status of the cellulose insulation. Only − In case of signals from gas or pressure relay. the most commonly used and important measurements are − Directly after, and within some weeks, after a short circuit. discussed here. − When a transformer essential to the network is taken into operation, followed by further tests after some months in 2.1 Electrical properties operation. 2.1.1 Breakdown voltage (IEC 60156) − After an obvious overloading of the transformers The ability of the oil to withstand electrical stress is obviously an important parameter in itself. A lowering of the breakdown The analysis results are documented in reports that are sent voltage is usually due to the presence of particles in the oil, in to the customer. All recent and historical results and recom- particular in combination with a large water content (figure 4). mendation are also available by a Web service (iTrafo). 2.1.2 Dielectric dissipation factor, tan δ (IEC 60247) 2. SUPERVISION OF OIL CONDITION This is a measure of the dielectric losses of the oil (figure 5). Even though it is generally acknowledged that dissolved gas These losses are due mostly to conductivity of the oil. It is analysis is normally the most powerful tool for diagnostic not as such a very important parameter for the operation of purposes, and for the detection of incipient faults in a trans- the transformer (unless the value is extremely high), but it is a former, it is also very important to monitor the general status good indication of the presence of dissolved metal ions and of the insulating oil. The oil may become contaminated with acids. water, particles and other foreign substances. There is also a continuous ageing of the oil and the solid insulating with the formation of water, acids and sludge. Apart from impairing the insulating properties, these oxidation products also cause accelerated degradation of the cellulose insulation. Figure 4. Breakdown voltage measurement cell. Figure 5. Apparatus for measurement of dielectric dissipation factor (tan δ). Dissolved gas analysis and supervision of oil condition in transformers and reactors 3 2.2 Chemical properties 2.3.2 Interfacial tension (“IFT”) (ASTM D971-99) 2.2.1 Water content (IEC 60814) The interfacial tension between oil and water is a measure of Some buildup of water content is inevitable, due to the aging the amount of polar contaminants and degradation products. processes mentioned above. There may also occur leakage of It is a useful indicator of aging, and a good complement to the water into the transformer by various mechanisms. Measure- acidity, because, as opposed to the latter, it is also influenced ment of the water content of the oil also allows the estimation by non-acidic oxidation products (figure 8).
Load more

Recommended publications
  • Electricity Today Issue 4 Volume 17, 2005
    ET_4_2005 6/3/05 10:41 AM Page 1 A look at the upcoming PES IEEE General Meeting see page 5 ISSUE 4 Volume 17, 2005 INFORMATION TECHNOLOGIES: Protection & Performance and Transformer Maintenance PUBLICATION MAIL AGREEMENT # 40051146 Electrical Buyer’s Guides, Forums, On-Line Magazines, Industry News, Job Postings, www.electricityforum.com Electrical Store, Industry Links ET_4_2005 6/3/05 10:41 AM Page 2 CONNECTINGCONNECTING ...PROTECTING...PROTECTING ® ® ® HTJC, Hi-Temperature Joint Compound With a unique synthetic compound for "gritted" and "non-gritted" specifications, the HTJC high temperature "AA" Oxidation Inhibitor improves thermal and electrical junction performance for all connections: • Compression Lugs and Splices for Distribution and Transmission • Tees, Taps and Stirrups on any conductor • Pad to Pad Underground, Substation and Overhead connections For oxidation protection of ACSS class and other connector surfaces in any environment (-40 oC to +250 oC), visit the Anderson ® / Fargo ® connectors catalogue section of our website www.HubbellPowerSystems.ca Anderson® and Fargo® offer the widest selection of high performance inhibitor compounds: Hubbell Canada LP, Power Systems TM ® ® 870 Brock Road South Inhibox , Fargolene , Versa-Seal Pickering, ON L1W 1Z8 Phone (905) 839-1138 • Fax: (905) 831-6353 www.HubbellPowerSystems.ca POWER SYSTEMS ET_4_2005 6/3/05 10:41 AM Page 3 in this issue Publisher/Executive Editor Randolph W. Hurst [email protected] SPECIAL PREVIEW Associate Publisher/Advertising Sales 5 IEEE PES General Meeting has
    [Show full text]
  • Transformer Diagnostics, June 2003
    FACILITIES INSTRUCTIONS, STANDARDS, AND TECHNIQUES VOLUME 3-31 TRANSFORMER DIAGNOSTICS JUNE 2003 UNITED STATES DEPARTMENT OF THE INTERIOR BUREAU OF RECLAMATION REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suit 1204, Arlington VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Report (0704-0188), Washington DC 20503. 1. AGENCY USE ONLY (Leave Blank) 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED June 2003 Final 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS FIST 3-31, Transformer Diagnostics 6. AUTHOR(S) Bureau of Reclamation Hydroelectric Research and Technical Services Group Denver, Colorado 7. PERFORMING ORGANIZATIONS NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION Bureau of Reclamation REPORT NUMBER Denver Federal Center FIST 3-31 PO Box 25007 Denver CO 80225-0007 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING Hydroelectric Research and Technical Services Group AGENCY REPORT NUMBER Bureau of Reclamation DIBR Mail Code D-8450 PO Box 25007 Denver CO 80225 11. SUPPLEMENTARY NOTES 12a. DISTRIBUTION AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE Available from the National Technical Information Service, Operations Division, 5285 Port Royal Road, Springfield, VA 22161 13.
    [Show full text]
  • Request for Input on Use of Transformer Dissolved Gas Analysis Data
    Request for Input on Use of Transformer Dissolved Gas Analysis Data CIMug Asset Health Focus Community August 2013 The CIM Users Group, in conjunction with the IEC TC57 Working Groups responsible for the CIM (Common Information Model), has established an Asset Health Focus Community, whose purpose is to develop CIM standards support for asset health. The intent is to develop use cases and requirements for a CIM standards framework to support best-of-breed practices that might include integration of data from various data sources, including operations, maintenance, and condition monitoring sources; application of analytics to this multi-faceted data set; and launching notifications and work orders. Utility input into the work of the Focus Community is crucial to the development of a high quality model, useful for solving real-world integration problems. Dissolved gas analysis (DGA) has been chosen as the first area of data model development and your assistance in providing insight into both the sources and uses of DGA data at your utility would be very much appreciated. Oil sampling for DGA 1. How frequently are DGA oil samples taken from transformers for DGA testing? (if frequency varies by type or current health of transformer, please explain) GSU’s > 10MVA: 3months GSU’s < 10MVA: 6 months Transmission Autotransformers: Yearly All other Transmission & Distribution transformers <230kV High Side: Yearly 2. What lab(s) do you utilize for DGA analysis of oil samples? Alabama Power Company has its own in-house laboratory for testing DGA samples. The data is automatically trended by the lab and notification given of out-of –limit conditions.
    [Show full text]
  • Dissolved Gas Analysis for Transformers
    Niche Market Testing Dissolved Gas Analysis for Transformers by Lynn Hamrick ESCO Energy Services ransformer oil sample analysis is a useful, predictive, maintenance tool cal, or corona faults. The rate at which for determining transformer health. Along with the oil sample quality each of these key gases are produced depends largely on the temperature T tests, performing a dissolved gas analysis (DGA) of the insulating oil is and directly on the volume of material useful in evaluating transformer health. The breakdown of electrical insulating at that temperature. Because of the volume effect, a large, heated volume materials and related components inside a transformer generates gases within the of insulation at moderate temperature transformer. The identity of the gases being generated can be very useful infor- will produce the same quantity of gas mation in any preventive maintenance program. There are several techniques for as a smaller volume at a higher tem- perature. Therefore, the concentrations detecting those gases and DGA is recognized as the most informative method. of the individual dissolved gases found This method involves sampling the oil and testing the sample to measure the con- in transformer insulating oil may be centration of the dissolved gases. It is recommended that DGA of the transformer used directly and trended to evaluate the thermal history of the transformer oil be performed at least on an annual basis with results compared from year to internals to suggest any past or poten- year. The standards associated with sampling, testing, and analyzing the results tial faults within the transformer. After samples have been taken and are ASTM D3613, ASTM D3612, and ANSI/IEEE C57.104, respectively.
    [Show full text]
  • Dissolved Gas Analysis in Transformer Oil Using Transformer Oil Gas Analyzer
    APPLICATION NOTE Gas Chromatography Authors: Tracy Dini Manny Farag PerkinElmer, Inc. Shelton, CT Dissolved Gas Analysis in Transformer Oil Using Introduction Nearly 90% of the world’s population does not Transformer Oil Gas Analyzer know life without the ubiquity of electricity. It is a luxury that gets taken for granted by most people and TurboMatrix HS Sampler every day. Panic often ensues when the electricity supply is interrupted, as witnessed in Manhattan during the July 13, 2019 blackout that left over 73,000 people without electricity for several hours. While no injuries or fatalities were reported in this case, history offers many accounts of chaos and safety risks following blackouts of this magnitude, especially in a major metropolitan city. To prevent such interruptions in electrical power, transformers must be properly maintained and monitored. An effective means of conducting routine monitoring towards this goal of reduced blackouts includes the analysis of oil insulting the transformers. Acting as both an insulator and coolant, insulating oil in electrical transformers is expected to meet demanding chemical, electrical, and physical properties to ensure proper functioning of the transformer and its internal components. The American Society for Testing and Materials (ASTM) offers reference test methods as guidance for performing required routine analysis on the oil. As the insulating oil is subjected to high intensity thermal and electrical conditions, decomposition occurs over time and forms gases that dissolve into the oil. ASTM D3612 Method C is a standard test method using a headspace sampler to extract these dissolved gases for GC analysis. Dissolved gas analysis (DGA) is performed on the oil to identify the gases and their concentrations.
    [Show full text]
  • Download the 2021 IEEE Thesaurus
    2021 IEEE Thesaurus Version 1.0 Created by The Institute of Electrical and Electronics Engineers (IEEE) 2021 IEEE Thesaurus The IEEE Thesaurus is a controlled The IEEE Thesaurus also provides a vocabulary of almost 10,900 descriptive conceptual map through the use of engineering, technical and scientific terms, semantic relationships such as broader as well as IEEE-specific society terms terms (BT), narrower terms (NT), 'used for' [referred to as “descriptors” or “preferred relationships (USE/UF), and related terms terms”] .* Each descriptor included in the (RT). These semantic relationships identify thesaurus represents a single concept or theoretical connections between terms. unit of thought. The descriptors are Italic text denotes Non-preferred terms. considered the preferred terms for use in Bold text is used for preferred headings. describing IEEE content. The scope of descriptors is based on the material presented in IEEE journals, conference Abbreviations used in the Thesaurus: papers, standards, and/or IEEE organizational material. A controlled BT - Broader term vocabulary is a specific terminology used in NT - Narrower term a consistent and controlled fashion that RT - Related term results in better information searching and USE- Use preferred term retrieval. UF - Used for Thesaurus construction is based on the ANSI/NISO Z39.19-2005(2010) standard, Guidelines for the Construction, Format, and Management of Monolingual Controlled Vocabulary. The Thesaurus vocabulary uses American-based spellings with cross references to British variant spellings. The scope and structure of the IEEE Thesaurus reflects the engineering and scientific disciplines that comprise the Societies, Councils, and Communities of the IEEE in *Refer to ANSI/NISO NISO Z39.19-2005 addition to the technologies IEEE serves.
    [Show full text]
  • A Study of Life Time Management of Power Transformers at E. ON's
    A study of life time management of Power Transformers at E. ON’s Öresundsverket, Malmö Chaitanya Upadhyay June 2011 Supervisors: Jonas Stenlund, E.ON Värmekraft Olof Samuelsson, LTH Examiner: Gunnar Lindstedt, LTH Preface This Master’s Thesis was carried out at E.ON Värmekraft, Öresundsverket in Malmö in cooperation with Division of Industrial Engineering and Automation at Faculty of Engineering at Lund University. This work is the final part of my master’s degree in electrical engineering. During this project, I have got quite a lot support and help and first of all would like to thank E.ON Värmekraft for giving the opportunity to carry out this project. I would also like to thank my supervisors, Jonas Stenlund at E.ON Värmekraft and Olof Samuelsson at the Division of Industrial Electrical Engineering and Automation, LTH for their help and support. I would like to further thanks to Mårten Svensson at Vattenfall, Mark Wilkensson at SMIT transformer, ABB power transformers team and many more who took their precious time to help and guide in this project. Chaitanya Upadhyay Malmö, June 2011. Abstract The objective of this master thesis is to review the present and future condition of generator step up power transformers at the combined heat and power plant Öresundsverket, in Malmö. The objective of this work was to prolong the lifetime of power transformers at Öresundsverket. The thermal properties of power transformer are been taking into consideration for their life time assessment. The most suitable thermal model was chosen which can prolong life to these transformers in the future.
    [Show full text]
  • University of Southampton Research Repository Eprints Soton
    University of Southampton Research Repository ePrints Soton Copyright © and Moral Rights for this thesis are retained by the author and/or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder/s. The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders. When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given e.g. AUTHOR (year of submission) "Full thesis title", University of Southampton, name of the University School or Department, PhD Thesis, pagination http://eprints.soton.ac.uk UNIVERSITY OF SOUTHAMPTON FACULTY OF PHYSICAL AND APPLIED SCIENCES Electronics and Computer Science Identification of Partial Discharge Sources and Their Location within High Voltage Transformer Windings by M. S. Abd Rahman Thesis for the degree of Doctor of Philosophy June 2014 UNIVERSITY OF SOUTHAMPTON ABSTRACT FACULTY OF PHYSICAL AND APPLIED SCIENCES Electronics and Computer Science Doctor of Philosophy IDENTIFICATION OF PARTIAL DISCHARGE SOURCES AND THEIR LOCATION WITHIN HIGH VOLTAGE TRANSFORMER WINDINGS by M. S. Abd Rahman This thesis is concerned with developing a new approach to high voltage transform- ers condition monitoring, which involve partial discharge (PD) measurement and lo- calisation within high-voltage transformer windings. This is an important source of information for both diagnosis and prognosis of the health of power transformers. Gen- erally, Partial discharges (PDs) existence in transformer windings are normally due to ageing processes, operational over stressing or defects introduced during manufacture.
    [Show full text]
  • Fluid Degradation Measurement Based on a Dual Coil Frequency Response Analysis
    sensors Article Fluid Degradation Measurement Based on a Dual Coil Frequency Response Analysis Jose M. Guerrero 1 , Alejandro E. Castilla 1, José Ángel Sánchez-Fernández 2 and Carlos A. Platero 1,* 1 Department of Automatic Control, Electrical and Electronic Engineering and Industrial Informatics, Universidad Politécnica de Madrid, E-28006 Madrid, Spain; [email protected] (J.M.G.); [email protected] (A.E.C.) 2 Department of Hydraulic, Energy and Environmental Engineering, Universidad Politécnica de Madrid, E-28040 Madrid, Spain; [email protected] * Correspondence: [email protected] Received: 17 June 2020; Accepted: 23 July 2020; Published: 26 July 2020 Abstract: Electrical industry uses oils for cooling and insulation of several machines, such as power transformers. In addition, it uses water for cooling some synchronous generators. To avoid malfunctions in these assets, fluid quality should be preserved. To contribute to this aim, a sensor that detects changes in fluid composition is presented. The designed sensor is like a single-phase transformer whose magnetic core is the fluid whose properties will be measured. The response of this device to a frequency sweep is recorded. Through a comparison between any measurement and a reference one corresponding to a healthy state, pollutants presence, such as water in oil or salt in water, can be measured. The performance of the sensor was analyzed through simulation. In addition, a prototype was built and tested measuring water concentration in oil and salt content in water. The correlation between pollutant concentration measured with the sensor and known pollutant concentrations is good. Keywords: degradation; fault diagnosis; frequency response analysis; predictive maintenance; oil insulation; capacitive sensors; magnetic sensors 1.
    [Show full text]
  • Application of Dissolved Gas Analysis in Assessing Degree of Healthiness Or Faultiness with Fault Identification in Oil-Immersed
    energies Article Application of Dissolved Gas Analysis in Assessing Degree of Healthiness or Faultiness with Fault y Identification in Oil-Immersed Equipment George Kimani Irungu * and Aloys Oriedi Akumu Department of Electrical Engineering, Tshwane University of Technology, Pretoria West Private Bag X680, Pretoria 0001, South Africa; [email protected] * Correspondence: [email protected] Note: this is a beef up of our conference paper titled “Comparison of IEC60599 gas ratios and an integrated y Fuzzy-Evidential reasoning approach in fault identification using dissolved gas analysis”. 51st Intern. Universities Power Engineering Conf. (UPEC), Coimbra Portugal, 2016, pp. 205–211. doi:10.1109/UPEC20168114055. Available: http://ieeexplore.ieee.org. Received: 3 August 2020; Accepted: 25 August 2020; Published: 12 September 2020 Abstract: The healthiness and or faultiness of oil-immersed electrical equipment using dissolved gas characterization has remained a critical and challenging task in power systems. Dissolved gas analysis (DGA) continues to be the utmost preferred technique of detecting mainly slow evolving thermal and electrical faults. However, DGA can reveal more than just faults in equipment. This research looks at broad areas where DGA can be applied to determine the healthiness or faultiness of equipment in addition to fault identification. In equipment considered normal—i.e., fault-free—DGA can give the degree of healthiness (DOH) based on Rogers ratios C2H2/C2H4 < 0.1, 0.1 < CH4/H2 < 1, and C2H4/C2H6 < 1, plus the 3 < CO2/CO < 10 ratio for identifying fault-free devices. This answers the question: How healthy or normal is the equipment? Similarly, when these ratios are violated, it signifies the presence of faults, and two things ought to be determined.
    [Show full text]
  • A Review on Fault Detection and Condition Monitoring of Power Transformer
    International Journal of Advanced and Applied Sciences, 6(8) 2019, Pages: 100-110 Contents lists available at Science-Gate International Journal of Advanced and Applied Sciences Journal homepage: http://www.science-gate.com/IJAAS.html A review on fault detection and condition monitoring of power transformer Muhammad Aslam 1, *, Muhammad Naeem Arbab 2, Abdul Basit 1, Tanvir Ahmad 1, Muhammad Aamir 3 1US Pakistan Centre for Advanced Studies in Energy, University of Engineering and Technology, Peshawar, Pakistan 2Department of Electrical Engineering, University of Engineering and Technology, Peshawar, Pakistan 3Faculty of Electrical Engineering, Bahria University, Islamabad, Pakistan ARTICLE INFO ABSTRACT Article history: Real-time monitoring of transformers ensures equipment safety and Received 15 March 2019 guarantees the necessary intervention in precise time thereby reducing the Received in revised form risk of non-schedule energy blackouts. Many utilities monitor the condition 18 June 2019 of the components that make up a power transformer and use this Accepted 19 June 2019 information to minimize interruption and prolong life. Currently, routine and diagnostic tests are used to monitor conditions and assess the aging and Keywords: defects of the core, windings, bushings and power transformer tape Transformer changers. To accurately assess the remaining life and probability of failure, Incipient fault methods have been developed to correlate the results of different routine Condition based monitoring and diagnostic tests. There are several electrical and chemical (diagnostic) Insulation deterioration techniques available for condition monitoring of power transformer. This Electrical fault paper reviews real time techniques used for condition-based monitoring of power transformer. © 2019 The Authors. Published by IASE.
    [Show full text]
  • Transformer Oil Testing
    Transformer Oil Testing By Robert Turcotte, Manager, Electrical Loss Control The Hartford Steam Boiler Inspection and Insurance Company The Value Of Transformer Oil Testing Transformer Oil Testing is a proven loss prevention technique which should be a part of any condition- based predictive maintenance program. This early warning system can allow maintenance management to identify maintenance priorities, plan work assignment schedules, arrange for outside service, and order necessary parts and materials. Hartford Steam Boiler uses test results in its Transformer Oil Gas Analyst (TOGA ) program, for instance, to diagnose transformer problems. The transformer’s fluid not only serves as a heat transfer medium, it also is part of the transformer's insulation system. It is therefore prudent to periodically perform tests on the oil to determine whether it is capable of fulfilling its role as an insulant. Some of the most common tests for transformer oil are: Dissolved Gas In Oil Analysis, screen tests, water content, metals-in-oil, and polychlorinated biphenyl (PCB) content. In this article, we will examine the value and benefits of each test. Dissolved Gas-In-Oil Analysis The most important test that can be done on the liquid insulation of a transformer is an annual Dissolved Gas Analysis (DGA). This test can give an early indication of abnormal behavior of the transformer. As the name implies, this test analyzes the type and quantity of gases that are dissolved in the transformer oil. ©1996-2011 The Hartford Steam Boiler Inspection and Insurance Company. All rights reserved. 1 | P a g e http://www.hsb.com/Thelocomotive Disclaimer statement: All recommendations are general guidelines and are not intended to be exhaustive or complete, nor are they designed to replace information or instructions from the manufacturer of your equipment.
    [Show full text]