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Academic literature on the topic 'Прогнозування строку служби'
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Journal articles on the topic "Прогнозування строку служби"
Шатров, А. М., Д. С. Печура, В. Г. Березанський, and А. С. Хижняк. "Методичний підхід до прогнозування строків служби керованим засобам ураження із заданою достовірністю." Системи озброєння і військова техніка, no. 4(64), (December 17, 2020): 133–37. http://dx.doi.org/10.30748/soivt.2020.64.17.
Full textVoloshin, S. M. "Terms of repair works and forecasting of terms of service of contacts of disassembly type in conditions of incomplete of output information." Naukovij žurnal «Tehnìka ta energetika» 11, no. 3 (November 18, 2020): 17–22. http://dx.doi.org/10.31548/machenergy2020.03.017.
Full textKozyrskyi, V. V., I. P. Tkachuk, S. M. Voloshin, and I. I. Slushnyi. "Dynamic control by contact tisk in powered electric contacts with use shape memory alloys." Naukovij žurnal «Tehnìka ta energetika» 10, no. 4 (November 11, 2019): 13–17. http://dx.doi.org/10.31548/machenergy2019.04.013.
Full textDissertations / Theses on the topic "Прогнозування строку служби"
Василевський, Володимир Валентинович. "Прогнозування строку служби силового трансформатора за допомогою комплексної моделі технічного стану целюлозної ізоляції." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/39553.
Full textThesis for granting the Degree of Candidate of Technical sciences in speciality 05.09.01 – Electric machines and apparatus. – National Technical University "Kharkiv Politechnical Institute", 2019. The thesis is dedicated to the improvement of mathematical models for forecasting the residual lifetime of a power transformer and the feasibility study of its maintenance strategy by developing a complex model of cellulose insulation technical condition. The complex model of the cellulose insulation technical condition, which consists of a mathematical model of the transformer's real resource formation at the stage of its production and a model of the resource consumption of the power transformer's cellulose insulation during the exploitation phase, is proposed. The mathematical model of water exchange in the system of cellulose insulation - transformer oil in the interrelation with other mathematical models, describing the condition of the transformer in exploitation is developed. The analysis of the effect of maintenance of power transformer (in particular, drying of the active part) on the characteristics of cellulose insulation is carried out. The transformer resource consumption modeling for different maintenance strategies is executed. The simulation justified the need to take into account the maintenance in the calculations of the residual resource and the modeling of the insulation resource consumption in operation. The calculation method for determining the reduction of insulation's lifetime was further developed by adjusting the known formula of the integral of aging by more accurate interpolation of the original data used to construct the dependence of the rate of aging on the moisture content of the insulation. For the first time, mathematical models for assessing the influence of the production stage on the assigned resource, which differ by the imperfection of control and stochasticity of the process of resource change during the technological process, are proposed.
Василевський, Володимир Валентинович. "Прогнозування строку служби силового трансформатора за допомогою комплексної моделі технічного стану целюлозної ізоляції." Thesis, Запорізький національний технічний університет, 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/39554.
Full textThesis for granting the Degree of Candidate of Technical sciences in speciality 05.09.01 – Electric machines and apparatus. – National Technical University "Kharkiv Politechnical Institute", 2019. The thesis is dedicated to the improvement of mathematical models for forecasting the residual lifetime of a power transformer and the feasibility study of its maintenance strategy by developing a complex model of cellulose insulation technical condition. The complex model of the cellulose insulation technical condition, which consists of a mathematical model of the transformer's real resource formation at the stage of its production and a model of the resource consumption of the power transformer's cellulose insulation during the exploitation phase, is proposed. The mathematical model of water exchange in the system of cellulose insulation - transformer oil in the interrelation with other mathematical models, describing the condition of the transformer in exploitation is developed. The analysis of the effect of maintenance of power transformer (in particular, drying of the active part) on the characteristics of cellulose insulation is carried out. The transformer resource consumption modeling for different maintenance strategies is executed. The simulation justified the need to take into account the maintenance in the calculations of the residual resource and the modeling of the insulation resource consumption in operation. The calculation method for determining the reduction of insulation's lifetime was further developed by adjusting the known formula of the integral of aging by more accurate interpolation of the original data used to construct the dependence of the rate of aging on the moisture content of the insulation. For the first time, mathematical models for assessing the influence of the production stage on the assigned resource, which differ by the imperfection of control and stochasticity of the process of resource change during the technological process, are proposed.
Півень, М. Ю., and Отто Володимирович Григоров. "Прогнозування залишкового ресурсу кранів, що відпрацювали нормативний строк служби." Thesis, НТУ "ХПІ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/25285.
Full textПівень, М. Ю., and Отто Володимирович Григоров. "Прогнозування залишкового ресурсу кранів." Thesis, НТУ "ХПІ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/25185.
Full textМірчук, Ігор Анатолійович. "Підвищення експлуатаційних характеристик суднових кабелів за рахунок технологічних режимів охолодження та радіаційного опромінення електричної ізоляції." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2020. http://repository.kpi.kharkov.ua/handle/KhPI-Press/49276.
Full textPh.D. thesis undertaken in research specialization 141 "Electric Power Engineering, Electrical Engineering and Electric Mechanics" (14 – Electrical Engineering). – National Technical University "Kharkiv Polytechnic Institute", Ministry of Education and Science of Ukraine, Kharkiv, 2020. The dissertation is devoted to increasing of the operational properties of shipboard cables due to the technological modes of cooling and electron beam irradiation of insulation and sheath based on modern flame retardant halogen-free polymeric compounds, which provide the necessary complex of electrical, physical and mechanical properties with appropriate control of technological processes. To achieve this, the following tasks were set: – to prove the expediency of gradual cooling of polyethylene insulation of high-voltage power cables to ensure both operational parameters and stability of properties during operation; – to substantiate the application of the method of electro-thermal analogy for the construction of a mathematical model of cooling of insulated conductor taking into account the temperature distribution over the thickness of insulation in a non-constant thermal mode; – to develop a method of calculating the technological parameters of the cooling mode of power cable, based on the calculation of a nonlinear thermal equivalent circuit of insulated conductor in a non-constant thermal mode, taking into account dependence the thermal resistance and heat capacity of the insulation from the temperature by methods of discrete resistive equivalent circuits; – to determine the influence of technological cooling modes on the temperature distribution in the thickness of extruded in sulation and to justify the duration of the transition process, which corresponds to achievement of the same temperature over the entire thickness of power cables insulation various design at different time points, depending on the cooling water temperature; – to verify experimentally the efficiency of detecting technological defects in the design of the power shipboard cable by partial discharges values; – to create a methodology for optimizing the power shipboard cable with coaxial construction to ensure maximum heat flow power dissipation into the environment, which causes an increase in current load, if insulation thermal resistance provided; – to prove the efficiency of the use a protective polymer sheath with high thermal conductive properties to increase the current load of power shipboard cables; – to determine the effect of accelerated electron beam energy on the mechanical and electrical properties of shipboard cables and determine the irradiation coefficient range for insulation which provides an increase of operational characteristics, on the basis of correlation between the electrical and mechanical properties of filled with flame retardants halogen-free compound based on ethylene-vinyl acetate modified by electron beam; – to verify the efficiency of absorbed dose distribution along the perimeter and length of shipboard cables after irradiation according to obtained results of mechanical and thermal tests of polymeric halogen-free flame retardant protective sheath of cable; – to determine the thermal stability of the halogen-free flame-retardant polymeric protective sheath modified by irradiating, on basis of accelerated thermal aging, to predict the service life of shipboard cables and to substantiate the possibility of operation in conditions with high humidity and high operating temperatures for unscreened cable with unscreened twisted pairs and thermoplastic insulation and protective sheath. Object of research – technological modes of cooling and irradiation of electrical insulation of shipboard cables, based on halogen-free filled with flame retardants polyolefin compound. Subject of research – electrical, mechanical and thermal operational properties of the shipboard cables polymer insulation and sheath based on filled with flame retardants halogen-free compounds. Research methods. Theoretical and experimental studies are based on the use of methods of numerical and physical modeling of technological modes of cooling and electron beam irradiation of polymeric electrical insulation and protective sheath of shipboard cables. Methods of theory of non-stationary thermal conductivity to calculation of cooling mode of polymeric cable insulation. Differential equations of thermal conductivity and electrical conductivity. The method of electro-thermal analogies to determine the temperature distribution in the thickness of insulation at different time points, depending on the temperature of cooling water for shipboard power cable. Nonlinear thermal and electrical equivalent circuits of insulated conductor in transient thermal mode. Implicit Euler method and nodal potentials method for obtaining temperature distribution in thickness of cable insulation. A method of optimizing the design of the power cable provided cooling during operation to increase the current load. Thermal balance equation to determining the thermal resistance of insulation during operation. Irradiation crosslinking theory to determine the optimal irradiation dose of polymeric insulation. The theory of thermal aging of insulation to predict the service life of shipboard cables. Approximation of experimental electrical, mechanical and thermal properties of modified by irradiation insulation of shipboard cables. Correlation and regression analysis of electrical, mechanical and thermal properties after modification by irradiation of polymeric insulation and protective sheath of shipboard cables. Partial discharge detection technique in high voltage solid polymeric insulation for defect detection on technological stage of production power shipboard cable. The following scientific results are obtained in the work. The dissertation solves the scientific and practical problem of increasing the operational properties of shipboard cables due to the technological modes of cooling and irradiation of electrical insulation based on modern halogen-free flame retardant polymeric compounds. The mathematical model of technological process of cooling insulated conductor in unsteady thermal mode, by taking into account dependence of thermal and physical characteristics of polymeric insulation from the temperature, for determine the temperature distribution throughout the thickness of polyethylene insulation at different time points depending on water temperature under gradual cooling, has been improved. Mathematical model allows to determine the conditions for ensuring stable characteristics of the shipboard power cable during operation. The criterion for determination of technological parameters of the cooling mode of power shipboard cables, which is the time of the transitional process of cooling the insulated conductor to achieve an equal temperature throughout the thickness of the polymeric insulation, is proposed. The optimum thickness of the polymeric protective sheath on condition of long-term thermal stability of irradiated cross-linked based on polyolefin insulation has been established. It provides a 30 % increase current load of the coaxial design shipboard power cable. The range of irradiation coefficient for halogen free flame retardant insulation of shipboard cables when guarantees increasing electrical resistance of polymeric insulation modified by electron beam more than twice, the breakdown direct current voltage 1,3 times relative to the non-irradiated condition, is determined. The correlation between mechanical and electrical properties of halogen-free based on polyolefin insulation modified by electron beam, depending on the linear velocity of the cable under the electron beam and constant value of electron beam current. The distribution of the absorbed dose along the perimeter and length of the halogen-free flame retardant polymeric protective sheath depending on the technological parameters of the irradiation modes of shipboard cables, is established and allows to determine the irradiation dose for cables, when protective sheath provides increasing the resistance to aggressive chemicals while high physical and mechanical properties is still available. The stability of the cables structure to high temperature and humidity is experimentally proved on the basis of accelerated aging of unscreened cable with unscreened twisted pairs, with thermoplastic polyethylene insulation and protective polyvinylchloride sheath with adequate aging during operation. It allows predicting the service life of shipboard cables depending on the operating temperature. A technique for calculating the technological parameters of the power cable cooling mode by the methods of discrete resistive equivalent circuits has been developed. A technique based on the calculation of a nonlinear thermal scheme of substitution of conductor with polyethylene insulation in a non-constant thermal mode, taking into account the dependence of thermal resistance and heat capacity from the temperature. The proposed methodology and algorithms can be applied to determine the technological modes of cooling cable polymeric insulation without using expensive full-scale experiments, especially important for the new compounds development and cable constructions, as well as modernization available at cable factories equipment for cooling power cable, data cable with twisted pairs, radio frequency and optical cables. The efficiency of determining partial discharges in high-voltage solid insulation has been proved to detect defects at the technological stage of the producing of power shipboard cables, as well as to adjust the technological process of cooling. The methodology for heat transfer in a coaxial design single-core power cable based on criterial equations of natural convection has been developed to optimize the design of the power shipboard cable to ensure the maximum linear density of heat flow dissipated from the cable surface. The efficiency of application of polymeric materials based on micro- and nanocomposites with high thermal conductivity for sheath of high-voltage shipboard cables, providing a 30 % increase in thermal dissipating of power cable, is shown. It is established the energy of accelerated electrons 0.5 MeV provides a higher degree of crosslinking of polymeric halogen-free insulation based on filled with flame retardants compound compared to the energy of 0.4 MeV at the same irradiation coefficient, electron beam current and the number of wire passages under electron beam. It is established an increase of tensile strength, electrical insulation resistance and breakdown DC voltage of crosslinked polymeric halogen-free insulation with irradiation coefficient 5-7 m/(mА∙min) with constant value of elongation at break not less than 120 % which ensure a compromise between rigidity and flexibility of the shipboard cable. It is established an increase in 1,5–2 times the time of reaching the critical parameter – elongation at break of the modified by electron beam polymeric sheath based on a halogen-free compound compared to the same thermop lastic non-modifying sheath. It is an increase service life of the shipboard control cable at maximum operational temperatures in 1,5–2 times. The materials of the dissertation are used at the educational process Department of Electrical Insulating and Cable Technique of National Technical University "Kharkiv Polytechnic Institute" at education bachelors and masters in disciplines of specialty "141 – Electric Power Engineering, Electrical Engineering and Electric Mechanics" (specialization "141.04 Electrical Isolating, Cable and Fiber-Optic Technique"), at "Azov Cable Company" (Berdians'k) at development and determination of optimal technological parameters of production modes of halogen-free, flame retardant shipboard cables, Association "Ukrelectrocable", in PJSC "Yuzhkable Works". Dissertation work was performed at the PJSC "Ukrainian Scientific and Research Institute of Cable Industry" (Berdians'k) and Department of Electrical Insulating and Cable Technique of National Technical University "Kharkiv Polytechnic Institute" (Kharkiv) according to research programs of PJSC "Ukrainian Scientific and Research Institute of Cable Industry" (PM EIUV.505.564–2018 "The research of thermal stability of the sheath cable SPOVEng-FRHF 12x2,5 before and after exposure under electron beam", PM EIUV.505.584–2019 "Determination of the quantity and distribution of the absorbed dose after irradiation of the sheath of shipboard flame retardant cables") wherein the applicant was one of the program developers and executor of individual sections.