State Petroleum Technological University
Author list of organization
List of articles written by the authors of the organization
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SIMULATION OF A POWER TRANSFORMER WORK WITH A HIGH LEVEL OF HIGHER HARMONICS
Description
The importance of improving the quality of electrical energy was growing along with the development and wide implementation in the production of valve converters and various highperformance processing units, such as arc furnace, welding machines etc. The main causes of potential and existing non-compliances of non-sinusoidal voltages can be joining sources and non-sinusoidal reactive power sources, including resonant filters, to existing electric grids without taking into account their possible impact on the distortion of the sinusoidal voltage. Transformers are affected by the non-sinusoidal shapes of the curves of current and voltage. The effect is characterized by the fact that the harmonics of current and voltage increase transformer temperature, compared to purely sinusoidal current and voltage. The aim of this work is to study the influence of higher harmonics on power loss in power transformers. Experimental study of operation of power transformers was carried out on the developed model of the transformer substation. The experiments were conducted with different capacities of transformers that have variables in the range of 250-1000 kVA. By using programmable voltage source a sinusoidal voltage is formed containing the third, fifth, sixth, seventh, ninth and twelfth harmonics. The level of harmonics is changed in the range of 2-12 %
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FILTRATION-WAVE HEATING OF THE OIL POOL
Description
We have developed a mathematical model of thermodynamic processes at oscillatory movement of liquids in porous environment with consideration of heat interaction of an oil layer with surrounding breeds and phase transitions caused by dissolution of paraffin’s dissolution. We have received analytical dependences of temperatures on time, distances to well and depth, that proves an opportunity to increase of oilrecavery when influenced by periodic fields of pressure. We have suggested a bartering effect to increase the temperature in zones far from the well formation. The mathematical model is based on the equation of heat balance, taking into account the contribution of phase transitions due to paraffinization in the case when the motion of the mixture takes place in a homogeneous isotropic porous medium with constant porosity and constant density. In the work we have developed a theory of bartering effect upon oscillatory movement of fluids in porous media considering thermal interaction between the oil reservoir and surrounding rocks and phase transitions due to the dissolution of paraffins. Comparison of theoretical and experimental data has confirmed the possibility of using the first approximation for the calculation of real thermodynamic processes in the filtration-wave fields. The developed process model allows the calculation of the temperature field in the practical conditions
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05.13.10 Management in social and economic systems
Description
The management of the process of implementation of projects at the refinery should be carried out comprehensively. To improve the diagnostic system of insulation of the stator windings of electric motors with a voltage above 1 kilovolt, it is necessary to involve specialists of all sub-divisions. This will allow a comprehensive approach to the problem of reducing the intensity of labor, and, consequently, to reduce the norms of time for performing operations provided for by the technological process. It is proposed to create a project team consisting of the following specialists: General Director, chief designer, chief electrician, lead engineer for adjustment and testing, Deputy Director for production, head of the Department of labor and wages, chief economist. In addition, the design should involve the heads of shops and sites, directly managing and organizing processes in the workplace. Domestic and foreign experience shows that the introduction of diagnostic tools is one of the most important factors in increasing the economic efficiency of the use of equipment in the industry. Purpose of diagnostics is identification and prevention of failures and malfunctions, maintenance of operational indicators within the established limits, forecasting of a condition for the purpose of full use of a resource
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05.20.01 Technologies and means of mechanization of agriculture (technical sciences)
Description
Both domestic and foreign experience have noted that the introduction of diagnostic tools was one of the most important factors in increasing the economic efficiency of the use of equipment in industry. The purpose of diagnostics is detection and prevention of failures and failures, maintenance of operational parameters within the specified limits, forecasting of the state for the purpose of full use of the resource. Today, more than ever, the assessment of the current state of the electric power is particularly acute. With one regulatory method of testing electric motors, it was necessary to make a sufficiently in-depth analysis of technical documentation for testing or diagnosis of new modern tests or diagnostics. The relevance of the transition to non-destructive methods of motor testing is increased in order to increase their service life. At present, there is a need to introduce more gentle methods of testing electric bodies, since the standardized test method has a negative impact on the condition of electric motors as a whole and on the integrity of the structure. In order to ensure the necessary level of reliability of electrical equipment at enterprises, it is necessary to use modern testing methods and diagnostic systems
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