Mineral oil is the most common insulating fluid and has been in use since the late 19th century. The white oil with 250 ppm of dbds was tested using astm test method d 1275b aging an abraded copper strip for 48 hours at 150c. The transformer oil testing device measures and reports the root mean square value of the breakdown voltage. Results and discussions leakage current measurement for clean oil, oil with dbds and oil with dbpc at different concentrations are tabulated and graphically shown. Along with an indepth commentary on the key influencing factors, market statistics in terms of revenues, segmentwise data, regionwise data, and country. Transformer oil, a type of insulating and cooling oil used in transformers and other electrical equipment, needs to be tested periodically to ensure that it is still fit. A transformer oil breakdown test set is an equipment that measures the dielectric strength of the oil.
If a transformer becomes overloaded for any reason, the windings will generate more heat and deteriorate the cellulose insulation. As the name implies, this test analyzes the type and quantity of gases that are dissolved in the transformer oil. Table 2 furan content ppm dp value significance 00. Oil immersed power transformers condition diagnosis with limited. Transformer oil or insulating oil is an oil that is stable at high temperatures and has excellent. Pour point of transformer oil it is the minimum temperature at which oil starts to flow under standard test condition. Detects most internal faults, some external faults and some operational errors. As oil has to be broken down into very specific forms such as transformer oil, making sure it is still in the correct form is an essential process. This application note points to the precautions that need to be taken. Clean oil with a low moisture content gives higher bdv results than oil with high moisture content and other conducting impurities. The white oil with 250 ppm of dbds was tested using astm test method d 1275b aging. Dissolved gasin oil analysis the most important test that can be done on the liquid insulation of a transformer is an annual dissolved gas analysis dga. So, insulation overheating measurement is also transformer oil testing methods. All oil delivered in bulk is pumped into the trucks at a breakdown voltage in excess of 70 kv.
As the insulating materials in a transformer break down due to thermal and electrical stresses, gaseous byproducts are formed. Coconut oil as an alternative to transformer oil pdf. A new transformer oil should have at lest a dielectric strength of 39 kv. They can now be applied to transformers filled with beta fluid. Transformer oil market global industry analysis, size and. Test parameters test method ref standard 01 interfacial tension ring method is. From my experience, untreated, raw transformer oil has to withstand 40 kv per 2. A dga test can identify an overloaded transformer by a test result showing high carbon monoxide, high carbon dioxide, and in extreme cases, even elevated methane and ethylene. Schedule 4 distribution transformer technical specifications distribution transformer 1.
Introduction transformer oil is one of the very important components in oil immersed transformers. Dissolved gas analysis is the single most important test performed on oils from transformers. If remedial action is required to the transformer oil, a recent pcb analysis is required in. The megger guide to insulating oil dielectric breakdown. Transformer oil should preferably be filtered before being transferred into high voltage apparatus. Oil in large transformers and electrical apparatus is periodically tested for its electrical. It should not be transferred from one package to another. For measuring bdv of transformer oil, portable bdv measuring kit is generally available at site. Oils that combine a high flashpoint with high dielectric strength have long been used as an insulating medium in transformers, switchgear and other electrical. In addition there are contaminations caused due to chemical interactions with windings and other solid insulations, catalyzed by high operating temperature. It is an optional component in high vacuum transformer oil filtration machine which is provided if the customer demands it. Destruction of dibenzyl disulfide in transformer oil lance. Transformer oil will be obtained by fractional distillation and subsequent treatment of crude oil.
Transformer oil market size, share global industry report. The byproducts are characteristic of the type of incipientfault condition. Each component of the transformer has a different electrical potential and therefore there is a constant risk of short circuiting. The global transformer oil market size was estimated at usd 1. Transformer oil, a type of insulating and cooling oil used in transformers and other electrical equipment, needs to be tested periodically to ensure that it is still fit for purpose.
What is bdv test for distribution transformer answers. Transformer oil analysis testing service for monitoring the condition of transformer oils routine testing of transformer insulating oil is an essential maintenance function that ensures a safe working environment and helps eliminate the possibility of disrupted production resulting from a transformer failure or explosion. Oil to be tested is placed in a cell containing one pair of electrodes placed with a gap of 2. Transformer oil testing quick, simple and onsite b2hv. For measuring bdv of transformer oil, bdv measuring kit is used. On before take oil samples you should confirm the moisture particles removed are not. How to take transformer oil break down voltage test.
The electrical properties of oil can suddenly change due to changes in oxidation, acids, sludge gas and even water absorption, so thats why its essential to regularly test oil samples for. Expansion in the power sector to meet growing electricity requirements has driven significant progress in the transformers industry. What is the minimum value of breakdown voltage of transformer. Gases generate by degradation of fluid or cellulose. After the transformer oil test is completed, the insulation oil is stirred automatically and the test sequence is performed repeatedly. In this kit, oil is kept in a pot in which one pair of electrodes are fixed with a gap of 2.
Samples are generally sent to a laboratory for analysis but portable equipment is available to perform the. Transformer oil maintenance electric energy online. The power factor of insulating oil is the ratio of true power to apparent power. For veryfication of oil purity every year to be checked the bdvbreakdown voltage,we have take out the transformer oil in the transformer and collect in the high voltage kit inthe kit two stem will be there within the 2mm gap and then apply the high. Transformer oil analysis basic introduction by n robinson, wearcheck as blood tests disclose ones state of health, so oil analyses disclose the condition of a transformer. Abbs mobile transformer oil processing service will restore the performance and extend the service life of any make of oilfilled transformer. Oilimmersed power transformers condition diagnosis with. The bdv of oil in transformer is 60 kv1 min within the gap of 2. Further, frequency domain spectroscopy fds as a novel nondestructive testing technique to estimate remained life expectancy is included in aging evaluation system. Please refer to the addendum for an explanation of the doble ccd test. Dissolved gas analysis of transformer oil electrical4u. The top seal has probably failed also allowing air and moisture to enter the top. Degasification, insulating oil, moisture, purification, transformer.
Also, bdv can be an indication about the deterioration state of the insulation system in the transformer. Testing sequences and procedures are defined by various international standards, many of them set by astm. Gray transformer chemistry services introduction the fault free operation of power transformers is a factor of major economic importance and safety in power supply utilities and industrial consumers of electricity. Jun 03, 2016 transformer oil will be obtained by fractional distillation and subsequent treatment of crude oil. Bdv test is an very important testing procedure for the insulation oils in transformer. Transformer oil breakdown voltage gives an indication about the dielectric capability of transformer oil to withstand high electrical stresses. Transformer oil market size, share global industry. The automatically generated test reports are provided in pdfformat and are stored on a usb stick. There are different types of sulfur compounds found in refined transformer oil. The transformer oil is used in the transformer for insulation as well as for cooling purpose. Isovoltine transformer oil safety and longevity in operation, a transformer reaches very high temperatures. At first thing you maintain the electrical normsto take one sample from top of transformer and one from the bottom of transformer.
The different insulating materials have different dielectric strength. Low value of bdv indicates presence of moisture content and conducting substances in the oil. The transformer oil performs two important functions. Power transformers, regulators, and reactors, ieee 62. The megger guide to insulating oil dielectric breakdown testing. Whenever a transformer undergoes abnormal thermal and electrical stresses, certain gases are produced due to the decomposition of the transformer oil. Then solid materials and oil were put in the ageing test vessel. Interfacial tension is exactly useful for determining the presence of polar contaminants and oil decay products. Dissolved gas analysis dga is the study of dissolved gases in transformer oil.
It requires a lubricant to prevent overheating and break down. The distribution of these gases can be related to the type of electrical fault, and the rate of gas generation can indicate the severity of the fault. Dissolved gas analysis guide for transformers filled with. Too high an oil level in a bushing generally means the seal in the bottom of the bushing has failed and oil head from the conservator, or nitrogen pressure, has pushed transformer oil up the bushing. Transformer oil analysis preventative maintenance program. Equipment should not be condemned by one test but by a series of tests. The dga test measures dissolved gases in the transformer oil and is capable of detecting. This test can give an early indication of abnormal behavior of the transformer. When you say bdv you might mean the dielectric strength of transformer oil. For typical power transformer, with an oil to paper ratio of 20.
The life expectancy and satisfactory operation of transformers are mainly dependent on the oil in which it is used. Transformer oil testing and oil analysis transformer oil and other insulating liquids suffer from electrical and mechanical stresses while a transformer is in operation. Also, bdv can be an indication about the deterioration state of. During the transformer operation for a period, insulation oils will become dirty degradation which results in loosing function of the oil in transformer as insulation and cooling, in that case.
Properties of transformer oil industrial lubricants. Testing consists of measuring breakdown voltage and. After this process, the humidity content of solid samples was less than 0. Transformer testing, transformer oil analysis lab, transformer oil test lab, oil transformer test sl no. It is fully automatic test kit developed to test oil sample as per is6792iec 60156 with printer facility. Dissolved gasinoil analysis the most important test that can be done on the liquid insulation of a transformer is an annual dissolved gas analysis dga. Oil test kit with semi hv transformer circular electrodes 220v100kv single phase auto transformer single phase 220v ac supply fig. In a transformer, a high power factor is an indication of significant power loss in the insulating oil, usually as a result of contaminants such as water, oxidized oil and cellulose paper degradation. Transformer oil testing transformer testing california. In general, the solubilities and thermal decomposition products of beta fluid are very similar to those from conventional transformer oil. In this paper, we will study about the transformer oil filtration machine and how it purifies the contaminated transformer oil. Effect of dbds and dbpc on paper oil insulation of power. Moreover, a software system based on transformers electrical and thermal parameters is developed correspondingly, by using a multiparameters. A transformer with transformer oil is used in the transformer for insulation as well as for cooling purpose.
Insulating materials within transformers and electrical equipment break down to liberate gases within the unit. All these compounds are hydrocarbons, so transformer oil is is a pure hydrocarbon mineral oil. Product information dissolved gas analysis and supervision of. Properties of transformer oil industrial lubricants, oils. Transformer oil testing for dielectric strength vessel preparation and elimination of the effects of moisture and contamination play a major role in successful oil testing. Service contract for carrying out the transformer oil. Due to the ultra fast voltage switchoff at flash over oil, the vacuum was switched off in and samples maintained in oil at atmospheric pressure during 24h. This transformer oil market study offers a comprehensive analysis of the business models, key strategies, and respective market shares of some of the most prominent players in this landscape. If regularly conducted, oil analysis allows identification of specific fault conditions that may be developing. A rating of 30 kv is the minimum breakdown voltage at which transformer oil can be safely used in a power transformer.
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