Study The Electrical Stress Withstand Properties Of Heated .
Study the Electrical Stress Withstand Properties of Heated Refined Bleachedand Deodorized Palm Oil DielectricsILHAM ABDUL HADI KADIMA thesis submitted in fulfillment of the requirement for the award of theMaster’s Degree of Electrical EngineeringFaculty of Electrical EngineeringUniversity Tun Hussein Onn MalaysiaJune 2015
viABSTRACTThe world’s energy requirement has been dominated by petroleum oil forcenturies in many application fields, including transportation, household, andelectricity. Mineral oil as an important insulating material in transformers has beenused more than 150 years. Mineral oil application in power system equipment can bepotentially hazardous to the environment especially when there are any incidentsduring operational time like transformer explosion which may cause a spill of oil tothe soil or water stream. Due to the concerns about the deducing petroleum resourcesand the environmental issues, the alternative insulating oil with biodegradablecharacteristics has been attracted lots of attentions for a couple of decades. In thisthesis, the dielectric properties of a type of mineral oil (Transformer Oil) and a typeof vegetable oil (RBDPO) were investigated, and the effect of heating on theirdielectric properties were studied as well. Since the heating effects on the dielectricproperties of insulating oil, such as breakdown voltage, kinetic viscosity, pH Value,In addition to the partial discharge performance under the heating condition wasstudied. All the experiments in this project were conducted at a heating condition forthe temperatures of 25⁰C, 50⁰C, 70⁰C, and 90⁰C. RBDPO was compared withpetroleum based mineral oil. The results of experiments incorporated showed thepotential of oil as a substitute RBDPO to the petroleum-based mineral oil. The BDVtests incorporated showed that the high BDV for RBDPO enables it to avoid abreakdown when the electric stressed. The average value of the BDV increasesslightly as the increase of the temperature. The potential of RBDPO, as an electricalinsulating liquid, to replace the petroleum-based mineral oil also can be concludedfrom the viscosity and acidity tests. From the experiments and analysis, it has beenproven that the RBDPO is a good insulation because the kinetic viscosity forRBDPO is low and very near from the viscosity of the petroleum-based mineral oilafter heating the oil to 50⁰C and above.
viiABSTRAKKeperluan tenaga dunia telah didominasi oleh minyak petroleum selamabeberapa dekad dalam pelbagai bidang aplikasi, termasuk pengangkutan,perumahan dan tenaga elektrik. Minyak mineral telah digunakan lebih dari 150tahun kerana ianya bertindak sebagai bahan penebat yang penting dalampengubah voltan (transformer). Aplikasi minyak mineral ini dalam perkakassistem kuasa mempunyai potensi risiko berbahaya kepada persekitaranterutamanya apabila berlakunya insiden yang tidak diingini sewaktu waktuoperasi seperti letupan pengubah voltan yang akan mengakibatkan penumpahanminyak kepada tanah atau sungai. Isu berkaitan kekurangan sumber petroleumdan persekitaran telah menarik perhatian kepada penggunaan minyak penebatalternatif yang mempunyai ciri-ciri penguraian bakteria selama beberapa dekad.Dalam tesis ini, sifat-sifat dielektrik juga telah dikaji. Pemanasan terhadap sifatsifat dielektrik bagi minyak penebat memberi kesan seperti kerosakan voltan,kelikatan kinetik dan nilai pH. Tambahan lagi, hasil kerja discaj separa (partialdischarge) dalam keadaan pemanasan juga telah dikaji. Semua eksperimen dalamprojek ini telah dijalankan pada suhu pemanasan setinggi 25 C, 50 C, 70 C dan90 C. Hasil kajian eksperimen RBDPO telah dibandingkan dengan hasil kajianeksperimen menggunakan minyak mineral berasaskan petroleum. Dapatandaripada eksperimen yang terkumpul membuktikan bahawa minyak berpotensisebagai pengganti RBDPO kepada minyak mineral berasaskan petroleum. UjianBDV terkumpul menunjukkan bahawa nilai BDV yang tinggi untuk RBDPOmembolehkan ia untuk menahan kerosakan bawah tegasan elektrik. PotensiRBDPO sebagai cecair penebat elektrik untuk menggantikan minyak mineralberasaskan petroleum juga boleh disimpulkan daripada ujian kelikatan dankeasidan. Hasil eksperimen dan analisa membuktikan bahawa RBDPO asalahpenebat yang baik kerana kelikatan kinetik bagi RBDPO adalah rendah danmenghampiri kelikatan minyak mineral berasaskan petroleum selepas pemanasanminyak tersebut sehingga 50⁰C dan keatas.
viiiTABLE OF CONTENTSTITLETITLE PAGEPAGEError! Bookmark not BSTRACTABSTRAKCONTENTSCHAPTER 1CHAPTER 2vviviiviiiLIST OF TABLESxiLIST OF FIGURESxiiiLIST OF ABBREVIATIONSxviLIST OF APPENDICESxviiINTRODUCTION1.1Study Background11.2Problem Statements41.3Objectives51.4Scope of Research51.5Thesis Outline6LITERATURE REVIEW2.1Introduction7
ix2.22.3Oil as Insulator72.2.1Mineral Oil92.2.2Ester Oil10Oil Application Inside Transformer122.3.1Electrical Insulation132.3.2Cooling System132.3.3Diagnostic Purpose142.4Vegetable Oil for Insulation142.5Palm Oil162.6Insulating Oil Properties172.6.1Breakdown Voltage172.6.2Viscosity202.6.3Viscometer212.6.4pH Value222.6.5pH Meter222.7Fourier Transform Infrared242.8Partial Discharge252.9Measurements Methods of Partial Discharge282.9.1Straight Detector282.9.2Balanced Detection Method312.10PD Characteristics Investigations of Natural Oils32for High Voltage ApplicationsCHAPTER 32.11 Aging of Vegetable Oil332.1234Previous l Process373.3Oil Samples Preparation393.4Viscosity Test413.5pH Value Test423.6Partial Discharge Experiment433.6.1Preparation of Test Cell433.6.2Preparation of Test Samples44
x3.6.3Partial Discharge Test3.7FTIR Test3.8Summary of Work454649CHAPTER 4: RESULT AND DATA ANALYSIS504.1Introduction4.2Physical Properties514.3Breakdown Voltage53544.4Partial Discharge Result644.5Chemical Assessment644.5.1 Mineral Oil (Transformer Oil)664.5.2Refined, Bleached and DeodorisedPalm Oil684.6Kinetic Viscosity Test Result4.7pH Value Test Result4.8Aging Results after PD Test724.9Chapter Summary7370CHAPTER 5: CONCLUSION AND RECOMMENDATION5.1Conclusion5.2Recommendations and Future WorksREFERENCESAPPENDICES75767883
xiLIST OF TABLENO.TITLE OF TABLEPAGECHAPTER 2Table 2.1Main Types of Mineral OilTable 2.2Advantages and Disadvantages between Natural and911Synthetic EsterTable 2.3Comparison Characteristics between Mineral Oil and12EsterTable 2.4Commercially Known Vegetable Transformer Oil15Breakdown Voltage Results of Mineral Oil and53CHAPTER 4Table 4.1RBDPOTable 4.2Partial Discharge Measurement for The Mineral Oil at5625⁰CTable 4.3Partial Discharge Measurement for the Mineral Oil at5750⁰CTable 4.4Partial Discharge Measurement for the Mineral Oil at5870⁰CTable 4.5Partial Discharge Measurement for the Mineral Oil at5990⁰CTable 4.6Partial Discharge Measurement for the RBDPO at6025⁰CTable 4.7Partial Discharge Measurement for the RBDPO at6150⁰CTable 4.8Partial Discharge Measurement for the RBDPO at70⁰C62
xiiTable 4.9Partial Discharge Measurement for the RBDPO at6390⁰CTable 4.10Percentages of Chemical Compounds of Transformer65OilTable 4.11Percentages of Chemical Compounds of RBDPO67Table 4.12Kinetic Viscosity Experiment for the Mineral Oil and68RBDPO at the Different TemperaturesTable 4.13pH Value Experiment for the Mineral Oil and RBDPO70at the Different TemperaturesTable 4.14Aging Results for Mineral Oil and RBDPO72
xiiiLIST OF FIGURENO.TITLE OF FIGUREPAGECHAPTER 2Figure 2.1Classification of Transformer Oil8Figure 2.2Synthetic Polyol Ester Structures10Figure 2.3Structure of Vegetable Oil (Triglyceride)11Figure 2.4Transformer Oil Applications13Figure 2.5Palm Oil Bunch16Figure 2.6Palm Oil Structure16Figure 2.7Electron Avalanche19Figure 2.8Streamer Breakdown Voltage19Figure 2.9Scheme of Typical Vibrating Viscometer Device21Figure 2.10Scheme of Typical pH Glass Electrode23Figure 2.11Infrared beam in FTIR24Figure 2.12Schematic of void representation and equivalent26circuit dielectricFigure 2.13Voltage and current traces of a partial discharge in a26voidFigure 2.14Sequences of void breakdown under alternating27voltagesFigure 2.15Methods of measurement28Figure 2.16Basic circuit of detection measurement29Figure 2.17Figure 2.18Straight discharge detection circuitElliptic sweep display2930Figure 2.19Balanced detection circuit using Schering Bridge31Figure 2.20Differential detector circuit31Figure 2.21Failed 25 kV Substation33
xivCHAPTER 3Figure 3.1Summarize of the Project Planning37Figure 3.2The Flow Chart Diagram of the Experimental Process38Figure 3.3A simplified scheme for the project39Figure 3.4Mineral Oil Samples Preparation40Figure 3.5Refined Bleached and Deodorized Palm Oil (RBDPO)40PreparationFigure 3.6Heating Process of Oil Samples40Figure 3.7Viscosity Test using Brookfield DV-II Pro Auto.Vis41Figure 3.8pH Value Test Using pH Meter42Figure 3.9Electrode Gap and Test Cell Design43Figure 3.10Test Cell44Figure 3.11Process of Oil Filling Into the Test Sample44Figure 3.12Schematic Equipment Arrangement for PD45Figure 3.13Actual Equipment Arrangement for the Partial Discharge46Figure 3.14Basic Operation of FTIR Machine47Figure 3.15The FTIR Machine and the Droppers48CHAPTER4Figure 4.1Flashover Happened Between the Spherical Electrodes of the Test51CupFigure 4.2Occurrence of Carbon during FlashoverFigure 4.3Colour Comparison of Transformer Oil (a) Pre BDV, (b) Post BDV 52Figure 4.4The Colour Comparison of RBDPO. (a) Pre BDV, (b) Post BDV52Figure 4.5Breakdown Voltage Results for Mineral Oil and RBDPO54Figure 4.6Column Chart for Breakdown Voltage54Figure 4.7PD Measurement for the Mineral Oil at the5552Temperature 25⁰CFigure 4.8PD Measurement for the Mineral Oil at the56Temperature 50⁰CFigure 4.9PD Measurement for the Mineral Oil at theTemperature 70⁰C57
xvFigure 4.10PD Measurement for the Mineral Oil at the58Temperature 90⁰CFigure 4.11PD Measurement for RBDPO at the Temperature6025⁰CFigure 4.12PD Measurement for RBDPO at the Temperature6150⁰CFigure 4.13PD Measurement for RBDPO at the Temperature6270⁰CFigure 4.14PD Measurement for RBDPO at the Temperature6390⁰CFigure 4.15FTIR Spectrum for Transformer Oil before PD Test64Figure 4.16FTIR Spectrum for Transformer Oil after PD Test65Figure 4.17FTIR Spectrum for RBDPO before PD Test66Figure 4.18FTIR Spectrum for RBDPO after PD Test67Figure 4.19Viscosity Results for RBDPO and Mineral Oil at the69temperature 25 ⁰C, 50⁰C, 70⁰C, and 90⁰CFigure 4.20Column Chart of Kinetic Viscosity for Mineral Oil and RBDPO69Figure 4.21pH Value Results for RBDPO and Mineral Oil at the71temperature25 ⁰C, 50⁰C, 70⁰C, and 90⁰CFigure 4.22Figure 4.23Column Chart of pH Value for Mineral Oil and RBDPOColumn Chart of Aging Results for Mineral Oil andRBDPO7173
xviLIST OF ABBREVIATIONSRBDPO- Refined Bleached and Deodorized Palm OilCPO- Crude Palm OilPD- Partial DischargeBDV- Breakdown VoltageAE- Acoustic EmissionRIV- Radio Influence VoltageIEC- International Electrotechnical CommissionFSTPI- Faculty of Science, Technology and HumanDevelopmentFKEE- Faculty of Electrical and Electronics EngineeringFKMP- Faculty of Mechanical and ManufacturingEngineering
xviiLIST OF APPENDICESAPPENDIXTITLEPAGEAExperimental Procedure83BGantt Chart of Master’s Project 194CGantt Chart of Master’s Project 294
1CHAPTER 1INTRODUCTION1.1Study BackgroundDielectric play important roles in electrical system to separating the electricalpotential object with the earthed object (including human), use as a medium ininsulating the electrodes (e.g. papers insulating winding transformer, PVC in cable).Failure in dielectric could cause electrical breakdown or short circuit in which mayintroduced the risk of faulty/damage to the equipment as well as causing potentialdanger to the human. In general, dielectric can be classified to solid (e.g. glass,porcelain, or composite polymer materials and etc.), gases (i.e. nitrogen and sulphurhexafluoride) and liquid such as mineral oils (e.g. naphthenic oil and paraffinic oil).These dielectric materials mainly used in the power transformer and the powersystem application such as in the AC capacitor, circuit breaker, switch gear, highvoltage bushings and etc. [1].The insulating oil provides electrical insulation and cooling in powertransformers. The enough knowledge of the dielectric behavior of these insulatingmaterials when in service in an electrical network could enhance network reliabilityand minimize the probability of failure. This makes the field of electrical insulationand dielectrics important in the electrical generation, transmission and distributionsystem.The main purposes of using oil in transformers are to increase the dielectricstrength between conductors by replacing air with a high dielectric strength fluid, and
2filling the pores of the cellulose paper and pressboard, to prevent discharges. The oilshould also have enough thermal and viscosity properties to be able to dissipate, byconvection, heat generated due to losses in the transformer and it must flow freelyunder all operating temperatures.For more than 100 years, mineral oils which are derived from crudepetroleum have been widely used in power transformers as the most commonlyliquid insulating for the purpose of cooling and insulation. However, concerns fromthe environmental effect of mineral oils such as soil and water contamination in theevent of a spillage can cause serious environmental disaster as they are nonbiodegradable [2]. This may disturb the plantation and other lives.The demand for environmentally friendly dielectric fluids in distribution andpower transformers is rising as the environmental impact of conventional fluidsbecomes increasingly more apparent. Vegetable based insulating oils are nowcommercially available as substitutes for mineral-based oils in transformerapplications. Some advantages offered by these oils, which are chemically classifiedas Natural Esters, are the faster biodegradability, no water hazard, higher flash/firepoints and low thermal expansion coefficient. Thus the application of these liquids inpower transformers promises strong benefits, compared to conventional mineraloil[3].Vegetable oils that have been proposed as a potential transformer have fattyacid triglyceride. Palm oil, as well as vegetable oils has fatty acid triglyceride. Oilswith a high percentage of unsaturated fatty acid resulting low viscosity but havegreater susceptibility to oxidation. Based on experiments on palm oil, the researchersfound that the refined, bleached and deodorized palm oil (RBDPO) monounsaturatedfatty acid content is high. Thus, RBDPO considered as an alternative to replace thelatest petroleum-based mineral oil [4].High voltage equipment is considered as one of the essential elements inelectrical network. Any failure in this equipment directly reduces network reliabilityand increases maintenance costs[5]. Under the high voltage stress micro levelelectrical sparks appears in an insulator medium which is known as partial dischargephenomenon. These micro discharges ultimately lead to electrical breakdown of theinsulator[6]. In any fabricated material some micro void spaces exist which is filledby the gas e.g. e air. This gas is ionized due to highly non-uniform electric field andultimately ruptures the void space in the weakest direction. The sudden release of
3energy due to the partial discharge phenomenon (PD) would produce a number ofeffects such as chemical and structural changes in the materials[7]. The measurementlevel indicates the quantity and magnitude of partial discharge.PDs are small events which occur in insulation in the presence of highelectric fields; in PD phenomenon energy is emitted in the form of electromagneticemission, radio waves, light and heat and also as acoustic emissions (AE) in theaudible and ultrasonic ranges. PD is an electrical discharge or sparks that bridgesmall part of insulating between two conducting electrodes. PD can occur whenelectric field strength exceeds the breakdown strength of insulation, and can lead toflashover [7]. A good understanding of PD mechanisms, characteristics and itsdevelopment processes is essential for power systems designer and power systemsinstallation maintenance engineer. PD detection is necessary as precautionarymeasures to ensure that high voltage equipment insulation is not exposed to anyunnecessary hazards.The electrical manifestation of PDs is a pulse of current on the line. Typicalvalues for the pulse area are in the Pico-coulomb range and for the duration– a few toa few hundred nanoseconds. The major difficulty with the electrical detection of PDsis the small magnitude of the current pulse as compared to the ambient current andnoise on the line, which may be orders of magnitude larger. However, most of thenoise energy is in the low frequency range (e.g. 50 Hz), whereas their energy isprimarily in the higher frequencies, since PDs are short events. This distinctionmakes it possible to extract the useful information. In addition to the low-frequencyrejection required of the system in order to accomplish this, filtering of specificdominant frequencies (such as 50 Hz) may further reduce the background noise.[8]There are other methods of measuring PDs, which do not provide on-line real timeresults. An example is the volumetric measurement of gas produced by PDs intransformer oil. However, they typically require interruptions of the operation andtime delays. This makes the availability of an on-line electrical method veryvaluable[9].For a reliable power system, improved functioning of power transformers aresignificant as they play a key role in the power transfer process. It can be observedthat the failure of a transformer leads to an unhealthy power system hence to a highmaintenance cost. The most possible reason for a failure of a transformer is
4insulation breakdown. Oil-impregnated pressboard and paper are commonly used asan insulation system in power transformers [10].1.2Problem StatementsIn the electric power equipment, insulation oil plays the roles of the electricalinsulation, heat dissipation and extinguishing voltaic arc by dipping and filling the airin the inner insulation of electric power equipment. Mineral oil has been widely usedin oil-impregnated electric equipment for many years. However, its flash point islow, which cannot meet the requirements of insulation materials’ fire prevention. Inthe fact, the mineral oil might run out in the future because it is extracted frompetroleum that is non-renewable energy source. Therefore, this petroleum-based oilneeds to be replaced with a new type of oil that is friendlier to the environment.Based on the previous studies that had been done, various types of vegetable-basedoil would be suitable to replace the petroleum-based oil due to its positive impacts.RBDPO is vegetable-based oil that has been modified in order to overcomeits high viscosity and poor oxidation problems. As for the time being, the propertiesof the RBDPO are best accepted to be a good insulating medium for transformers ascompared to mineral oils [4]. Since very few studies that had been done on RBDPO,it was reviewed that only dielectric properties of RBDPO has been studied.Furthermore, study for heating effect on the RBDPO has not yet been done since it isa new type of commercialized transformer oil. So it can be said that the heatingperformance on the dielectric properties of RBDPO and the partial discharge effectson the properties of RBDPO are not yet well studied significantly in order to achieveenvironmental friendly dielectric fluids in distribution and power transformers withthe functional operation impact of conventional fluids with wide used in distributionlevel transformers influencing factors on electrical properties.
51.3ObjectivesThis study would focus on the following objectives:a) To investigate the dielectric properties of RBDPO as electrical insulatingmaterial.b) To execute experimental study of
and Deodorized Palm Oil Dielectrics ILHAM ABDUL HADI KADIM A thesis submitted in fulfillment of the requirement for the award of the Master’s Degree of Electrical Engineering Faculty of Electrical Engineering U
May 02, 2018 · D. Program Evaluation ͟The organization has provided a description of the framework for how each program will be evaluated. The framework should include all the elements below: ͟The evaluation methods are cost-effective for the organization ͟Quantitative and qualitative data is being collected (at Basics tier, data collection must have begun)
Silat is a combative art of self-defense and survival rooted from Matay archipelago. It was traced at thé early of Langkasuka Kingdom (2nd century CE) till thé reign of Melaka (Malaysia) Sultanate era (13th century). Silat has now evolved to become part of social culture and tradition with thé appearance of a fine physical and spiritual .
Dr. Sunita Bharatwal** Dr. Pawan Garga*** Abstract Customer satisfaction is derived from thè functionalities and values, a product or Service can provide. The current study aims to segregate thè dimensions of ordine Service quality and gather insights on its impact on web shopping. The trends of purchases have
On an exceptional basis, Member States may request UNESCO to provide thé candidates with access to thé platform so they can complète thé form by themselves. Thèse requests must be addressed to esd rize unesco. or by 15 A ril 2021 UNESCO will provide thé nomineewith accessto thé platform via their émail address.
̶The leading indicator of employee engagement is based on the quality of the relationship between employee and supervisor Empower your managers! ̶Help them understand the impact on the organization ̶Share important changes, plan options, tasks, and deadlines ̶Provide key messages and talking points ̶Prepare them to answer employee questions
Chính Văn.- Còn đức Thế tôn thì tuệ giác cực kỳ trong sạch 8: hiện hành bất nhị 9, đạt đến vô tướng 10, đứng vào chỗ đứng của các đức Thế tôn 11, thể hiện tính bình đẳng của các Ngài, đến chỗ không còn chướng ngại 12, giáo pháp không thể khuynh đảo, tâm thức không bị cản trở, cái được
1.4 importance of human resource management 1.5 stress management 1.6 what is stress? 1.7 history of stress 1.8 stressors 1.9 causes of stress 1.10 four major types of stress 1.11 symptoms of stress 1.12 coping with stress at work place 1.13 role of human resource manager with regard to stress management 1.14 stress in the garment sector
Le genou de Lucy. Odile Jacob. 1999. Coppens Y. Pré-textes. L’homme préhistorique en morceaux. Eds Odile Jacob. 2011. Costentin J., Delaveau P. Café, thé, chocolat, les bons effets sur le cerveau et pour le corps. Editions Odile Jacob. 2010. Crawford M., Marsh D. The driving force : food in human evolution and the future.
