Window units account for the largest specific heat losses. The use of movable heat-reflecting screens and photovoltaic solar panels is of particular interest among the existing technologies to improve the thermal protection of windows. Despite the large number of scientific papers on this issue, which consider experimental laboratory studies and numerical simulation of heat transfer processes through window units, there is no data on the influence of the edge zones of a double-glazed window, as well as the areas of interface of the window profile and the light opening on the thermal processes that occur in these energy-saving units with screens. Vertical replacing of specific heat fluxes and temperature on the inner surface of the window unit strongly influences the correctness of determining the value of the minimum allowable temperature of the indoor air. Thus, the development and verification of models of the heat transfer process through a window unit with screens is an urgent task in the context of an indoor microclimate creation. Simulation numerical modeling is performed using the finite element method based on the fundamental laws of heat transfer. The authors have used the results of experimental studies of windows with heat-reflecting screens carried out in a certified climatic chamber. The authors have developed a two-dimensional simulation model of heat transfer through a window unit with heat-reflecting screens located in the partition wall of the climate chamber. The distribution of temperatures, air flow velocities, and reduced total thermal resistance along the height of a translucent structures has been studied. The adequacy of the proposed simulation model is confirmed by comparison with the results of the experiment in a certified laboratory, as well as data obtained by other authors and regulatory documentation. The use of heat-reflecting screens in the window unit increases the resistance to heat transfer by 1,6–3,7 times depending on their number. A significant decrease in temperature in the edge zones of the double-glazed window is revealed. The use of the developed simulation model makes it possible to determine the application of heat-reflecting screens in windows for intermittent heating systems including the case of using pre-drying air technology for humid, wet, or normal operation modes of industrial premises.
{"title":"Development and verification of simulation model of heat transfer process through window unit with heat-reflecting screens","authors":"G.I. Parfenov, N.N. Smirnov, A.K. Sokolov, V.V. Tyutikov, S.N. Yarunin, N.N. Yarunina","doi":"10.17588/2072-2672.2023.5.028-039","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.028-039","url":null,"abstract":"Window units account for the largest specific heat losses. The use of movable heat-reflecting screens and photovoltaic solar panels is of particular interest among the existing technologies to improve the thermal protection of windows. Despite the large number of scientific papers on this issue, which consider experimental laboratory studies and numerical simulation of heat transfer processes through window units, there is no data on the influence of the edge zones of a double-glazed window, as well as the areas of interface of the window profile and the light opening on the thermal processes that occur in these energy-saving units with screens. Vertical replacing of specific heat fluxes and temperature on the inner surface of the window unit strongly influences the correctness of determining the value of the minimum allowable temperature of the indoor air. Thus, the development and verification of models of the heat transfer process through a window unit with screens is an urgent task in the context of an indoor microclimate creation. Simulation numerical modeling is performed using the finite element method based on the fundamental laws of heat transfer. The authors have used the results of experimental studies of windows with heat-reflecting screens carried out in a certified climatic chamber. The authors have developed a two-dimensional simulation model of heat transfer through a window unit with heat-reflecting screens located in the partition wall of the climate chamber. The distribution of temperatures, air flow velocities, and reduced total thermal resistance along the height of a translucent structures has been studied. The adequacy of the proposed simulation model is confirmed by comparison with the results of the experiment in a certified laboratory, as well as data obtained by other authors and regulatory documentation. The use of heat-reflecting screens in the window unit increases the resistance to heat transfer by 1,6–3,7 times depending on their number. A significant decrease in temperature in the edge zones of the double-glazed window is revealed. The use of the developed simulation model makes it possible to determine the application of heat-reflecting screens in windows for intermittent heating systems including the case of using pre-drying air technology for humid, wet, or normal operation modes of industrial premises.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The priority directions of the scientific and technological policy of the Russian Federation include issues on research in the field of energy and resource saving technologies while generating heat and electric energy. One of the possible ways to implement it at thermal and nuclear power plants is to increase the efficiency of the operation of circulating cooling systems (COO). Modeling and optimization of circulating cooling systems with tower cooling towers is of particular relevance under modern conditions of a limited amount of low-mineralized water for charging circulating cooling systems. To determine the parameters of air flow in the tower cooling tower, a three-dimensional simulation model is developed. To describe heat and mass transfer, considering the phase transitions in coolants, a matrix model is used. The model is developed based on the mass and energy balance equations. A combined model of a circulating cooling system with cooling towers has been developed. It describes air flow within the framework of a three-dimensional simulation model and the process of heat and mass transfer, considering a possible phase transition in coolants within the framework of a matrix model. Comparison of modeling results and normative data is carried out. Adequate description of the real-life process using the combined model is presented. The developed combined model allows setting and solving problems of choosing the optimal design and operating parameters of the COO equipment, as well as solving problems of diagnosing the state of the COO according to the readings of standard instruments. In the future, the proposed calculation method will allow optimizing the operating modes of combined water supply systems, which combine water cooling in a direct-flow scheme and water cooling in a reverse scheme with cooling towers.
{"title":"Combined model of heat and mass transfer in cooling towers","authors":"V.P. Zhukov, M.D. Fomichev, E.V. Barochkin, E.A. Shuina, S.I. Shuvalov","doi":"10.17588/2072-2672.2023.5.090-096","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.090-096","url":null,"abstract":"The priority directions of the scientific and technological policy of the Russian Federation include issues on research in the field of energy and resource saving technologies while generating heat and electric energy. One of the possible ways to implement it at thermal and nuclear power plants is to increase the efficiency of the operation of circulating cooling systems (COO). Modeling and optimization of circulating cooling systems with tower cooling towers is of particular relevance under modern conditions of a limited amount of low-mineralized water for charging circulating cooling systems. To determine the parameters of air flow in the tower cooling tower, a three-dimensional simulation model is developed. To describe heat and mass transfer, considering the phase transitions in coolants, a matrix model is used. The model is developed based on the mass and energy balance equations. A combined model of a circulating cooling system with cooling towers has been developed. It describes air flow within the framework of a three-dimensional simulation model and the process of heat and mass transfer, considering a possible phase transition in coolants within the framework of a matrix model. Comparison of modeling results and normative data is carried out. Adequate description of the real-life process using the combined model is presented. The developed combined model allows setting and solving problems of choosing the optimal design and operating parameters of the COO equipment, as well as solving problems of diagnosing the state of the COO according to the readings of standard instruments. In the future, the proposed calculation method will allow optimizing the operating modes of combined water supply systems, which combine water cooling in a direct-flow scheme and water cooling in a reverse scheme with cooling towers.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"59 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.17588/2072-2672.2023.5.062-067
A.N. Golubev
A promising way to improve the technical and economic characteristics of an AC electric drive is to design it based on an executive synchronous motor with an increased number of phases of the stator winding. However, the specific nature of the m-phase (m > 3) synchronous motor is determined by the energy transfer by the whole spectrum of spatial harmonics of the field. Thus, the task is to design an electromechanical system that takes this feature into account. The author has used the method to study the adjustment characteristics of an m-phase synchronous motor based on spectral vectors of electromagnetic parameters reduced to spatial harmonics of the field. A multichannel principle of realization of an m-phase synchronous electric drive is proposed. It ensures the targeted formation of the electromagnetic state of a synchronous motor through all its energy channels as a control object. Various ways of its implementation are considered. The realization of the multiphase synchronous motor can be carried out based on of the forced mutual orientation of the flux linkage vectors and the stator current for higher spatial harmonics, which ensures the creation of additional constant components of the electromagnetic torque. This design of electric drives is advisable, in particular, for mobile installations with low-voltage (autonomous) power sources.
{"title":"Synchronous multiphase electric drive with multi-channel control","authors":"A.N. Golubev","doi":"10.17588/2072-2672.2023.5.062-067","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.062-067","url":null,"abstract":"A promising way to improve the technical and economic characteristics of an AC electric drive is to design it based on an executive synchronous motor with an increased number of phases of the stator winding. However, the specific nature of the m-phase (m > 3) synchronous motor is determined by the energy transfer by the whole spectrum of spatial harmonics of the field. Thus, the task is to design an electromechanical system that takes this feature into account. The author has used the method to study the adjustment characteristics of an m-phase synchronous motor based on spectral vectors of electromagnetic parameters reduced to spatial harmonics of the field. A multichannel principle of realization of an m-phase synchronous electric drive is proposed. It ensures the targeted formation of the electromagnetic state of a synchronous motor through all its energy channels as a control object. Various ways of its implementation are considered. The realization of the multiphase synchronous motor can be carried out based on of the forced mutual orientation of the flux linkage vectors and the stator current for higher spatial harmonics, which ensures the creation of additional constant components of the electromagnetic torque. This design of electric drives is advisable, in particular, for mobile installations with low-voltage (autonomous) power sources.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135975531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.17588/2072-2672.2023.5.012-018
V.V. Bukhmirov, A.K. Sokolov, S.N. Yarunin, N.N. Yarunina, N.N. Smirnov
Currently, in this country solid fuel at industrial thermal power plants, as a rule, is burned by a layer or flaring method in boilers with generation of steam which is directed to a steam turbine. This technology of generating thermal and electrical energy is characterized by relatively low efficiency and significant emissions of pollutants into the atmosphere. At the same time, the use of solid fuel in industrial energy with its preliminary gasification can significantly increase the efficiency of electricity generation and at the same time reduce the negative impact on the environment. The results of an analytical comparison of two schemes to use solid fuel in industrial energy are used as the material of the research. These two schemes are a traditional scheme and an alternative one based on its preliminary gasification. In this paper, to assess the effectiveness of the schemes under consideration, the scientific methodology of system analysis is applied. It allows us to consider any energy object as a unified system consisting of interrelated elements. The system analysis is carried out based on mathematical modeling of the technological process to obtain thermal and electrical energy. A complex balance mathematical model of an industrial thermal power plant with preliminary coal gasification is developed. The results of calculation using a mathematical model have shown that the construction of industrial combined‒cycle thermal power plants with preliminary coal gasification instead of traditional steam turbine ones will increase the key indicator of the energy efficiency of thermal power plants, coefficient of fuel utilization from 60 to 74 %. Based on the methodology of system analysis, an optimal thermal scheme of an industrial combined-cycle thermal power plant with preliminary coal gasification has been developed. Numerical values of the basic operating conditions of the thermal power plants and energy efficiency indicators have been determined using a mathematical model. The use of solid fuel at industrial thermal power plants with its preliminary gasification is a very promising direction to develop industrial energy in Russia since this method to extract the bound chemical energy of solid fuel can significantly increase the fuel utilization coefficient and the production of electrical energy and at the same time reduce emissions of contamination material into the atmosphere
{"title":"Improvement of efficiency of solid fuel use at industrial thermal power plants","authors":"V.V. Bukhmirov, A.K. Sokolov, S.N. Yarunin, N.N. Yarunina, N.N. Smirnov","doi":"10.17588/2072-2672.2023.5.012-018","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.012-018","url":null,"abstract":"Currently, in this country solid fuel at industrial thermal power plants, as a rule, is burned by a layer or flaring method in boilers with generation of steam which is directed to a steam turbine. This technology of generating thermal and electrical energy is characterized by relatively low efficiency and significant emissions of pollutants into the atmosphere. At the same time, the use of solid fuel in industrial energy with its preliminary gasification can significantly increase the efficiency of electricity generation and at the same time reduce the negative impact on the environment. The results of an analytical comparison of two schemes to use solid fuel in industrial energy are used as the material of the research. These two schemes are a traditional scheme and an alternative one based on its preliminary gasification. In this paper, to assess the effectiveness of the schemes under consideration, the scientific methodology of system analysis is applied. It allows us to consider any energy object as a unified system consisting of interrelated elements. The system analysis is carried out based on mathematical modeling of the technological process to obtain thermal and electrical energy. A complex balance mathematical model of an industrial thermal power plant with preliminary coal gasification is developed. The results of calculation using a mathematical model have shown that the construction of industrial combined‒cycle thermal power plants with preliminary coal gasification instead of traditional steam turbine ones will increase the key indicator of the energy efficiency of thermal power plants, coefficient of fuel utilization from 60 to 74 %. Based on the methodology of system analysis, an optimal thermal scheme of an industrial combined-cycle thermal power plant with preliminary coal gasification has been developed. Numerical values of the basic operating conditions of the thermal power plants and energy efficiency indicators have been determined using a mathematical model. The use of solid fuel at industrial thermal power plants with its preliminary gasification is a very promising direction to develop industrial energy in Russia since this method to extract the bound chemical energy of solid fuel can significantly increase the fuel utilization coefficient and the production of electrical energy and at the same time reduce emissions of contamination material into the atmosphere","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"37 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135975532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.17588/2072-2672.2023.5.051-061
V.R. Rafikov, I.E. Ivanov, A.Yu. Murzin, D.M. Dubinin
To enhance power system dependability and efficiency, it is of great importance to obtain correct parameters of the models of key power system components such as a synchronous generator (SG). Technology of synchronized phasor measurements allows us to estimate the SG model parameters through measurements in power system steady states and transients states, without switching the SG off and conducting complex testing procedures. The theory of electric circuits and electric machines, theory of optimization and statistics, and matrix algebra are applied in this study. The developed parameter estimation method has been implemented in the MATLAB software. The method has been verified through real-world measurements captured by a phasor measurement unit installed at a large power plant in the United Power System. This paper presents an algorithm of the turbogenerator synchronous reactance estimation via a set of synchrophasor data taken under steady-state conditions. Also, the paper considers the criteria for an appropriate data array ensuring successful parameter estimation. An algorithm has been developed and implemented in MATLAB software package. To improve the parameter estimation accuracy, an algorithm has been proposed to modify a nominal value for the SG no-load excitation current depending on the heating of the field winding. The algorithm has been successfully tested out based on a set of steady state synchrophasor data captured for one of the turbogenerators in the Russian United Power System. The authors have developed and analyzed quantitative criteria to determine a set of measured parameters of steady-state modes, providing the most accurate results of the turbogenerator synchronous reactance. The developed algorithm allows accurate update of the turbogenerator synchronous parameters through synchrophasor measurements recorded in a steady state modes of electric power systems. Using the criteria for selecting phasor data, it seems possible to automate the process of generating a data array of measurement of various steady-state modes necessary for identification. The proposed procedure that considers the field winding temperature can be employed in math models to estimate SG transient and subtransient parameters based on phasor measurements in transient modes of electric power systems.
{"title":"Algorithms of estimation of turbogenerator synchronous reactance and criteria of selecting proper synchrophasor measurement data sets","authors":"V.R. Rafikov, I.E. Ivanov, A.Yu. Murzin, D.M. Dubinin","doi":"10.17588/2072-2672.2023.5.051-061","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.051-061","url":null,"abstract":"To enhance power system dependability and efficiency, it is of great importance to obtain correct parameters of the models of key power system components such as a synchronous generator (SG). Technology of synchronized phasor measurements allows us to estimate the SG model parameters through measurements in power system steady states and transients states, without switching the SG off and conducting complex testing procedures. The theory of electric circuits and electric machines, theory of optimization and statistics, and matrix algebra are applied in this study. The developed parameter estimation method has been implemented in the MATLAB software. The method has been verified through real-world measurements captured by a phasor measurement unit installed at a large power plant in the United Power System. This paper presents an algorithm of the turbogenerator synchronous reactance estimation via a set of synchrophasor data taken under steady-state conditions. Also, the paper considers the criteria for an appropriate data array ensuring successful parameter estimation. An algorithm has been developed and implemented in MATLAB software package. To improve the parameter estimation accuracy, an algorithm has been proposed to modify a nominal value for the SG no-load excitation current depending on the heating of the field winding. The algorithm has been successfully tested out based on a set of steady state synchrophasor data captured for one of the turbogenerators in the Russian United Power System. The authors have developed and analyzed quantitative criteria to determine a set of measured parameters of steady-state modes, providing the most accurate results of the turbogenerator synchronous reactance. The developed algorithm allows accurate update of the turbogenerator synchronous parameters through synchrophasor measurements recorded in a steady state modes of electric power systems. Using the criteria for selecting phasor data, it seems possible to automate the process of generating a data array of measurement of various steady-state modes necessary for identification. The proposed procedure that considers the field winding temperature can be employed in math models to estimate SG transient and subtransient parameters based on phasor measurements in transient modes of electric power systems.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"84 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.17588/2072-2672.2023.5.068-073
A.B. Vinogradov, A.A. Korotkov, K.K. Ermakov
Mine dump trucks with a carrying capacity of 90 tons or more are equipped with an electromechanical transmission that controls the traction motors of the driving wheels. Due to unfavorable operation conditions of dump trucks, there are strict requirements to the driving safety along unpaved roads of open pits. The results of BELAZ dump trucks tests and authors maintenance experience have shown that the active security system is especially needed and gives essential assistance to a driver. Loss of control of а loaded truck, for example, during sharp braking on a slippery icy road, can lead to а serious accident and additional costs for repairing mining equipment. Thus, the development of traffic safety systems of mine dump trucks with electromechanical transmission is an important task. The methods of automatic control, mathematical modeling and numerical solution of differential equations are used to develop control algorithms for a mine dump truck. To test the proposed solutions, the method of full-scale experiment is used in real-life driving conditions along the dirt and icy roads. Control algorithms that use data of additional front (driven) wheels sensor are proposed. The results of tests of a BELAZ dump truck with a carrying capacity of 90 tons are presented. The results confirm the effectiveness of the developed control system in comparison with the one currently used in stock-produced items. The developed ABS system with speed sensors of the front wheels of a dump truck has proved the braking effectiveness along a slippery road. It makes it possible to improve the controllability of the dump truck significantly under conditions of lack of road adhesion, preventing the dump truck from skidding and wheels blocking. And it makes it possible to reduce mechanical effects on the transmission and anti-slip system sensitivity to different traffic conditions. The adaptive system remains operational if one of the front wheel sensors fails and if compared to the standard system it works equally effectively in various traffic conditions. The implementation of the obtained results will improve traffic safety and reduce the accident rate of expensive mining equipment.
{"title":"Dump truck control algorithms when wheels slip","authors":"A.B. Vinogradov, A.A. Korotkov, K.K. Ermakov","doi":"10.17588/2072-2672.2023.5.068-073","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.068-073","url":null,"abstract":"Mine dump trucks with a carrying capacity of 90 tons or more are equipped with an electromechanical transmission that controls the traction motors of the driving wheels. Due to unfavorable operation conditions of dump trucks, there are strict requirements to the driving safety along unpaved roads of open pits. The results of BELAZ dump trucks tests and authors maintenance experience have shown that the active security system is especially needed and gives essential assistance to a driver. Loss of control of а loaded truck, for example, during sharp braking on a slippery icy road, can lead to а serious accident and additional costs for repairing mining equipment. Thus, the development of traffic safety systems of mine dump trucks with electromechanical transmission is an important task. The methods of automatic control, mathematical modeling and numerical solution of differential equations are used to develop control algorithms for a mine dump truck. To test the proposed solutions, the method of full-scale experiment is used in real-life driving conditions along the dirt and icy roads. Control algorithms that use data of additional front (driven) wheels sensor are proposed. The results of tests of a BELAZ dump truck with a carrying capacity of 90 tons are presented. The results confirm the effectiveness of the developed control system in comparison with the one currently used in stock-produced items. The developed ABS system with speed sensors of the front wheels of a dump truck has proved the braking effectiveness along a slippery road. It makes it possible to improve the controllability of the dump truck significantly under conditions of lack of road adhesion, preventing the dump truck from skidding and wheels blocking. And it makes it possible to reduce mechanical effects on the transmission and anti-slip system sensitivity to different traffic conditions. The adaptive system remains operational if one of the front wheel sensors fails and if compared to the standard system it works equally effectively in various traffic conditions. The implementation of the obtained results will improve traffic safety and reduce the accident rate of expensive mining equipment.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"114 39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.17588/2072-2672.2023.5.019-027
V.A. Lebedev, A.S. Deev, A.D. Stupkin
Nuclear power plants (NPP) are characterized by low maneuverability. This fact exacerbates the problem of the balance of generated and consumed power when nuclear power plants are used as an energy source. This problem is especially relevant for isolated power systems. One of the ways to increase the maneuverability of nuclear power plants is to use heat accumulators directly in the NPP circuit. The study is carried out for two most attractive options of including a heat accumulator in the NPP circuit: 1) parallel to a high-pressure heater to heat feed water; 2) to generate additional steam for a low-pressure cylinder. The efficiency of each of the options is determined based on the calculation of thermal schemes of nuclear power plants with a heat accumulator. The authors have calculated the power of the turbine unit and electricity generation when a heat accumulator is included in the nuclear power plant circuit. The analysis of the data obtained shows that when using a heat accumulator in the NPP circuit in parallel with high pressure heater to heat feed water, the power of the turbine unit is increased by 7,2 % in the accumulator discharge mode, and additional electricity generation due to accumulated heat is 0,63 MJ for each kilogram of waste steam. When using a heat accumulator to generate additional steam for a low-pressure cylinder, the power of the turbine unit is increased by 6,6 % in the accumulator discharge mode, and the additional power generation due to the accumulated heat is 0,40 MJ per kilogram of waste steam. Application of heat accumulators in the NPP circuits will allow using the accumulated heat to generate additional electricity during high demand hours. Thus, the use of heat accumulators in NPP circuits is a way to increase the maneuverability of nuclear power plants, to reduce the negative impact of maneuverable modes on NPP equipment, and to reduce the number of liquid radioactive waste. The most effective and simple way to use the heat accumulator in the NPP circuit is to install it in parallel to the high-pressure heaters. In future, it is planned to determine the design of the heat accumulator, to model heat exchange processes in the heat accumulator
{"title":"Low-power NPP with heat accumulator with phase change material","authors":"V.A. Lebedev, A.S. Deev, A.D. Stupkin","doi":"10.17588/2072-2672.2023.5.019-027","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.019-027","url":null,"abstract":"Nuclear power plants (NPP) are characterized by low maneuverability. This fact exacerbates the problem of the balance of generated and consumed power when nuclear power plants are used as an energy source. This problem is especially relevant for isolated power systems. One of the ways to increase the maneuverability of nuclear power plants is to use heat accumulators directly in the NPP circuit. The study is carried out for two most attractive options of including a heat accumulator in the NPP circuit: 1) parallel to a high-pressure heater to heat feed water; 2) to generate additional steam for a low-pressure cylinder. The efficiency of each of the options is determined based on the calculation of thermal schemes of nuclear power plants with a heat accumulator. The authors have calculated the power of the turbine unit and electricity generation when a heat accumulator is included in the nuclear power plant circuit. The analysis of the data obtained shows that when using a heat accumulator in the NPP circuit in parallel with high pressure heater to heat feed water, the power of the turbine unit is increased by 7,2 % in the accumulator discharge mode, and additional electricity generation due to accumulated heat is 0,63 MJ for each kilogram of waste steam. When using a heat accumulator to generate additional steam for a low-pressure cylinder, the power of the turbine unit is increased by 6,6 % in the accumulator discharge mode, and the additional power generation due to the accumulated heat is 0,40 MJ per kilogram of waste steam. Application of heat accumulators in the NPP circuits will allow using the accumulated heat to generate additional electricity during high demand hours. Thus, the use of heat accumulators in NPP circuits is a way to increase the maneuverability of nuclear power plants, to reduce the negative impact of maneuverable modes on NPP equipment, and to reduce the number of liquid radioactive waste. The most effective and simple way to use the heat accumulator in the NPP circuit is to install it in parallel to the high-pressure heaters. In future, it is planned to determine the design of the heat accumulator, to model heat exchange processes in the heat accumulator","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"84 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The most complex models with the high quality of the results obtained are, as a rule, more expensive in terms of developer qualifications and computational resources. During process design, a detailed description of the object is often not required, and the accuracy of the results obtained should not be higher than the accuracy of the measuring instruments used. Thus, the optimal combination of simplicity and quality of the mathematical description of technological processes is an urgent task of mathematical modeling. To identify a cell model developed based on the theory of Markov chains, data obtained by solving discrete models of the Boltzmann equation are used. A method to identify cell models of a fluidized bed reactor has been developed using data obtained based on solving discrete models of the Boltzmann equation. The adequacy of the identified model of a fluidized bed reactor has been verified. An approach to develop computational support for a cell model based on the theory of Markov chains is presented. The analysis of the results obtained has shown an adequate description of the processes in fluidized bed reactors in terms of cell models. The models are developed based on the theory of Markov chains and identified based on the results obtained within the framework of discrete models of the Boltzmann equation. The proposed method to identify and verify cell models provides the possibility to obtain simultaneously acceptable indicators of model simplicity and the accuracy of calculation of the design and operating parameters of fluidized bed reactors.
{"title":"Method for identification of cell models of fluidized bed reactor based on discrete analogues of Boltzmann equation","authors":"V.P. Zhukov, A.N. Belyakov, N.S. Shpeynova, E.A. Shuina, I.D. Aksakovskiy","doi":"10.17588/2072-2672.2023.5.083-089","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.083-089","url":null,"abstract":"The most complex models with the high quality of the results obtained are, as a rule, more expensive in terms of developer qualifications and computational resources. During process design, a detailed description of the object is often not required, and the accuracy of the results obtained should not be higher than the accuracy of the measuring instruments used. Thus, the optimal combination of simplicity and quality of the mathematical description of technological processes is an urgent task of mathematical modeling. To identify a cell model developed based on the theory of Markov chains, data obtained by solving discrete models of the Boltzmann equation are used. A method to identify cell models of a fluidized bed reactor has been developed using data obtained based on solving discrete models of the Boltzmann equation. The adequacy of the identified model of a fluidized bed reactor has been verified. An approach to develop computational support for a cell model based on the theory of Markov chains is presented. The analysis of the results obtained has shown an adequate description of the processes in fluidized bed reactors in terms of cell models. The models are developed based on the theory of Markov chains and identified based on the results obtained within the framework of discrete models of the Boltzmann equation. The proposed method to identify and verify cell models provides the possibility to obtain simultaneously acceptable indicators of model simplicity and the accuracy of calculation of the design and operating parameters of fluidized bed reactors.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.17588/2072-2672.2023.5.040-050
S.G. Tiguntsev, K.V. Shafarevich
One of the problems to ensure the quality of electricity and reliability of the network is significant deviation of the voltage curve from sinusoidal in some active electricity transmission lines of the energy system of the Irkutsk region. The purpose of the research is to develop organizational and technical measures to eliminate resonance phenomena at higher harmonics that occur in the active 35 kV electrical line connected to a traction power substation. The object of the research is non-sinusoidal mode of the 35 kV electric power transmission line connected to the medium voltage winding of the three-winding traction transformer. The authors have used technological research methods of calculation using an equivalent circuit of the existing linear circuit of an electrical power system with a traction substation. The software “Calculation program of non-symmetric and non-sinusoidal modes of the electric power system” and Microsoft Excel are used for the research. The authors have developed a 110–35–10 kV “Consumer 1 – Consumer 2 – Consumer 3” model using the software “Calculation program of non-symmetric and non-sinusoidal modes of the electric power system”. The calculation results are processed using Microsoft Excel. Non-sinusoidal electrical modes of the equivalent circuit of the electrical power system and the power transmission lines are calculated. Calculation of non-sinusoidal modes of a 35 kV line is carried out to show the distribution of higher harmonic voltages along the line. It is established that the quality indicators of electricity in terms of non-sinusoidal voltages in most nodes of the 35 kV power transmission line do not comply with GOST 32144-2013. Calculation and analysis of non-symmetric and non-sinusoidal modes of the network have shown resonance voltage increase along the line on the odd harmonics frequencies and elimination of resonance factor when installing the compensation reactor at the beginning of the 35 kV line. Based on the calculation results, the diagrams of harmonics power-voltage curve from 3 to 39 are compiled. Based on the results obtained, the authors have proposed technical measures such as installation of a compensation reactor at the beginning of the electrical power system line to prevent resonance factor to improve the electrical power quality in terms of voltage unsinusoidality in the consumers busbars connected to the 35 kV line. The proposed measures will improve the electrical power quality in busbars of consumers and satisfy the requirements of GOST 32144-2013.
{"title":"Development of measures to eliminate resonant phenomena at higher harmonic frequencies on power line of 35 kV","authors":"S.G. Tiguntsev, K.V. Shafarevich","doi":"10.17588/2072-2672.2023.5.040-050","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.040-050","url":null,"abstract":"One of the problems to ensure the quality of electricity and reliability of the network is significant deviation of the voltage curve from sinusoidal in some active electricity transmission lines of the energy system of the Irkutsk region. The purpose of the research is to develop organizational and technical measures to eliminate resonance phenomena at higher harmonics that occur in the active 35 kV electrical line connected to a traction power substation. The object of the research is non-sinusoidal mode of the 35 kV electric power transmission line connected to the medium voltage winding of the three-winding traction transformer. The authors have used technological research methods of calculation using an equivalent circuit of the existing linear circuit of an electrical power system with a traction substation. The software “Calculation program of non-symmetric and non-sinusoidal modes of the electric power system” and Microsoft Excel are used for the research. The authors have developed a 110–35–10 kV “Consumer 1 – Consumer 2 – Consumer 3” model using the software “Calculation program of non-symmetric and non-sinusoidal modes of the electric power system”. The calculation results are processed using Microsoft Excel. Non-sinusoidal electrical modes of the equivalent circuit of the electrical power system and the power transmission lines are calculated. Calculation of non-sinusoidal modes of a 35 kV line is carried out to show the distribution of higher harmonic voltages along the line. It is established that the quality indicators of electricity in terms of non-sinusoidal voltages in most nodes of the 35 kV power transmission line do not comply with GOST 32144-2013. Calculation and analysis of non-symmetric and non-sinusoidal modes of the network have shown resonance voltage increase along the line on the odd harmonics frequencies and elimination of resonance factor when installing the compensation reactor at the beginning of the 35 kV line. Based on the calculation results, the diagrams of harmonics power-voltage curve from 3 to 39 are compiled. Based on the results obtained, the authors have proposed technical measures such as installation of a compensation reactor at the beginning of the electrical power system line to prevent resonance factor to improve the electrical power quality in terms of voltage unsinusoidality in the consumers busbars connected to the 35 kV line. The proposed measures will improve the electrical power quality in busbars of consumers and satisfy the requirements of GOST 32144-2013.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"330 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135975535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.17588/2072-2672.2023.5.074-082
N.E. Gnezdov, M.S. Kulenko, S.K. Lebedev, A.R. Kolganov
Ability of university graduates to design electric drives (ED) implies that they have knowledge and skills to develop software for microcontrollers (MC) used in modern electric drive control systems (ED CS). Studies on this topic touch upon the issues of particular training courses or teaching methods, and laboratory benches mean only debug boards. Often, education process is designed on a piecemeal basis. A systematic approach is required to teach students programming of microcontrollers of ED CS. In the context of restrictions of manufacturers from the USA, Japan and Europe, the selection of microcontroller for training and developing the ED CS is also topical. When developing the interrelated training courses, the authors have used 20 years of experience of design of ED CS. Product design software packages and metalworking technologies have been used as tools to develop a specialized laboratory bench. The method of comparative analysis is used when selecting microcontrollers. A multi-level (3-stage) model of interrelated training courses to teach students programming MC of ED CS is described. The evolution of the contents of training courses is shown. The author-developed bench is presented. It includes the debug board, measuring (multimeter, oscilloscope) and debugging (interface converters) equipment placed on a special unit. A review is given, an analysis of studies on these issues is carried out, and recommendations to select MC of ED CS in the current situation are given. Implemented at the department, a systematic approach to teach students programming MC of ED CS gives them the qualifications necessary to independently perform tasks during the design of modern ED CS. The developed laboratory bench provides convenient and safety work with all debugging and measuring equipment used in the educational process. An overview and recommendations on the selection of MC of domestic and Chinese manufacturers will be useful for the developers of the electrical drive control systems.
{"title":"Software design training system and selection of microcontrollers for electric drive control","authors":"N.E. Gnezdov, M.S. Kulenko, S.K. Lebedev, A.R. Kolganov","doi":"10.17588/2072-2672.2023.5.074-082","DOIUrl":"https://doi.org/10.17588/2072-2672.2023.5.074-082","url":null,"abstract":"Ability of university graduates to design electric drives (ED) implies that they have knowledge and skills to develop software for microcontrollers (MC) used in modern electric drive control systems (ED CS). Studies on this topic touch upon the issues of particular training courses or teaching methods, and laboratory benches mean only debug boards. Often, education process is designed on a piecemeal basis. A systematic approach is required to teach students programming of microcontrollers of ED CS. In the context of restrictions of manufacturers from the USA, Japan and Europe, the selection of microcontroller for training and developing the ED CS is also topical. When developing the interrelated training courses, the authors have used 20 years of experience of design of ED CS. Product design software packages and metalworking technologies have been used as tools to develop a specialized laboratory bench. The method of comparative analysis is used when selecting microcontrollers. A multi-level (3-stage) model of interrelated training courses to teach students programming MC of ED CS is described. The evolution of the contents of training courses is shown. The author-developed bench is presented. It includes the debug board, measuring (multimeter, oscilloscope) and debugging (interface converters) equipment placed on a special unit. A review is given, an analysis of studies on these issues is carried out, and recommendations to select MC of ED CS in the current situation are given. Implemented at the department, a systematic approach to teach students programming MC of ED CS gives them the qualifications necessary to independently perform tasks during the design of modern ED CS. The developed laboratory bench provides convenient and safety work with all debugging and measuring equipment used in the educational process. An overview and recommendations on the selection of MC of domestic and Chinese manufacturers will be useful for the developers of the electrical drive control systems.","PeriodicalId":497748,"journal":{"name":"Vestnik IGÈU","volume":"996 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135975536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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