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Valeriy Kuznetsov

Bio: Valeriy Kuznetsov is an academic researcher from Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan. The author has contributed to research in topics: Traction substation & Renewable energy. The author has an hindex of 5, co-authored 27 publications receiving 67 citations. Previous affiliations of Valeriy Kuznetsov include Oles Honchar Dnipropetrovsk National University.

Papers
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Journal ArticleDOI
TL;DR: In this article, a mathematical model of the induction generator-induction motor system with parametric asymmetry was developed to determine the quality of generated electricity in load operating modes, and the results of changes in the main characteristics of an induction motor at various degrees of parametric imbalance in the generator were presented.
Abstract: The paper presents studies of the system "induction generator-induction motor" with parametric asymmetry on a mathematical model to determine the quality of generated electricity in load operating modes. A mathematical model of the "induction generator-induction motor" system has been developed taking into account losses in steel and parametric asymmetry. The analysis of the transient characteristics of an induction generator when a motor load is connected in symmetrical and asymmetrical modes of operation is carried out. The results of changes in the main characteristics of an induction motor at various degrees of parametric asymmetry in the generator are presented. The quality of the generated electricity was analyzed based on the calculations of the unbalance coefficients for each of the operating modes. The assessment of the thermal state in steady-state conditions was carried out using an equivalent thermal equivalent circuit. Thermal transients were investigated when starting an induction motor from an autonomous energy source based on an induction generator. On a thermal mathematical model, the study of the effect of the output voltage asymmetry on the heating of the connected induction motor was carried out. It is shown that the asymmetry of the output voltage of an induction generator reaches 3–10 % and causes overheating of the windings in excess of the permissible values. A regression model has been developed for studying the operating conditions of an induction motor when powered by an induction generator with an asymmetry of the stator windings. The use of the obtained equations will make it possible to determine the most rational combination of factors affecting the heating of the stator windings of induction machines, in which they will not overheat above the maximum permissible temperature values of the corresponding insulation classes

11 citations

Journal ArticleDOI
TL;DR: Recommendations for the selection of parameters of shunting locomotives and the actual indicators of their work are analyzed, finding that the reduction in the duration of the elementary shunting movement is more significantly affected by the power of the locomotive than by the starting traction force.
Abstract: Shunting is an integral part of the partial process. In 1520 mm gauge countries, shunting operations are performed by outdated locomotives, which are being replaced by modern models; the technical parameters best match the conditions of the shunting work performed. The article analyzes recommendations for the selection of parameters of shunting locomotives and the actual indicators of their work. On the basis of this analysis, a requirement was made on the necessity of compulsory consideration of the operating conditions of the locomotive when determining its technical characteristics. As the main technical parameters of shunting locomotives, the tractive power and starting tractive force are taken and their influence on the duration of an elementary shunting movement of the \"acceleration-deceleration\" type is investigated. This approach advises the regulatory documentation for the organization of shunting work. Tha developed mathematical model allows to carry out research on the influence of tractive power and starting tractive force on the time of acceleration and deceleration. Calculations of the time of the train's acceleration are carried out with varying their mass and the slope of the track at different values of the tractive power starting tractive force. The calculations were carried out for the mass of compositions 1000...5000 Mg for the profile slopes equal to 0 and 1.5 ‰. The speed of the finish of acceleration was taken equal to 15 and 25 km/h. The thrust starting tractive force varied in the range of 150...300 kN, the tractive power - 200 ... 1100 kW. According to the results of calculations, it was found that the reduction in the duration of the elementary shunting movement is more significantly affected by the power of the locomotive than by the starting traction force. The “saturation” effect was noted, in which a significant increase in power or traction force during starting does not cause a significant reduction in the acceleration time. In this regard, for shunting locomotives with AC traction drive, it is recommended to take a pulling force of an equal continuous traction force.

10 citations

Journal ArticleDOI
03 Jan 2022-Energies
TL;DR: In this article , the authors developed a method of selecting energy-efficient parameters of an asynchronous electric traction motor for diesel shunting locomotives, which will ensure that its operating energy efficiency will be as high as possible.
Abstract: One of the assumptions made during the modernization process of diesel shunting locomotives is the replacement of a diesel traction motor with a DC generator with an electric asynchronous traction motor. The article aimed to develop a method of selecting energy-efficient parameters of an asynchronous electric traction motor for diesel shunting locomotives, which will ensure that its operating energy efficiency will be as high as possible. The method was verified on the example of a locomotive series ChME3 (ЧMЭ3, ČME3, ČKD S200). It has been found that using a traction asynchronous electric drive on a ChME3 locomotive, its efficiency increases in comparison with DC electric motors by 3–5% under the long-term operation modes and by 7–10% during locomotive operation with traction at the adhesion limit. Using a new traction gearbox with a higher gear ratio expands the speed range in which the asynchronous traction drive operates with a high-efficiency factor. It is effective to use a traction asynchronous electric drive to modernize ChME3 diesel locomotives in case of their use under the modes requiring the implementation of maximum traction forces at low speeds. A further increase in the efficiency of the traction asynchronous electric drive is possible based on the optimal design of the wheel-motor unit and the asynchronous traction electric drive.

9 citations

Journal ArticleDOI
TL;DR: The practical significance of the obtained results is the use of such a calculation method that does not require significant time for its implementation and can be used as a subsystem of the on-board train control system capable of performing calculations taking into account changes in the current train situation.
Abstract: Development of a method for calculating the optimal mode of conducting a train in terms of energy saving meet the safety requirements and schedules. The method of calculation must solve the assigned tasks without significant time spent on the calculation. To implement this method of calculation was used a simplified model of the train as a controlled system. The existing mathematical and algorithmic methods for solving isoperimetric problems of finding the optimal solution in the presence of restrictions on resources were the information base for methodology development. Scientific works of domestic and foreign scientists, professional periodicals, materials of scientific and practical conferences, methodical and normative materials, currently in force on Ukrainian Railways. The results of these studies were used to create simulators on the basis of computer technology for the training of locomotive drivers. The scientific novelty of the proposed calculation method consists in applying the simplified calculations of the status of the train as a controlled system, without the use of differential equations of motion that allows to significantly increase the speed of the calculations. This, in turn, will solve the problems of finding optimal control in real time, taking into account changing conditions during the movement of the train. The practical significance of the obtained results is the use of such a calculation method that does not require significant time for its implementation and can be used as a subsystem of the on-board train control system capable of per-forming calculations taking into account changes in the current train situation.

8 citations

Journal ArticleDOI
TL;DR: In this article, the authors proposed to increase the efficiency of export railway transportation of grain freights in Ukraine by the introduction of consignor routing, a concentration of loading of grain on junction elevators and the organization of the movement of grain routes according to the schedule.
Abstract: The research objective is to increase the efficiency of export railway transportation of grain freights in Ukraine by the introduction of consignor routing, a concentration of loading of grain on junction elevators and the organization of the movement of grain routes according to the schedule. According to the researchers in USA and EU, one of the effective directions for decreasing the expenses in a logistic chain of grain delivery to ports is consignor routing of railway transportation. Consignor routing of transportations of grain freights provides a concentration of their loading at junctions. The choice of junctions is proposed to be carried out on the basis of methods of the cluster analysis. For formation of regions for a concentration of grain loading the theory of sets and multicriteria optimization are used. As a result, on the basis of the modified simplex method are chosen 24 regions of possible concentration of grain loading that cover 70 stations on Ukrainian railways providing 7,5 million t consignor routing for grain in a year with minimal additional expenses. The assessment of the efficiency of railway transportation routing of grain freights is calculated with use of the developed simulation model. Researches showed that application of consignor routing allows to reduce a turnround cycle for grain wagon in a logistic chain of deliveries up to 27%, and application of the schedule for consignor routes allows to reduce a turn-round cycle up to 62%, in comparison with transportation by car loading. Thus, as showed the calculations executed for one of the directions of grain transportation for export, the necessary operation park of graincarrier wagons is reduced twice, thereby allowing to cut logistic expenses on a delivery of the Ukrainian grain through seaports to the world markets.

8 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the synergistic effect of organic additives, biodegradable vegetable base oils and recycling purification effectively reduces the environmental pollution of cutting fluids, which provides the basis and support for the engineering application and development of cutting fluid and its circulating purification.
Abstract: Cutting fluid has cooling and lubricating properties and is an important part of the field of metal machining. Owing to harmful additives, base oils with poor biodegradability, defects in processing methods, and unreasonable emissions of waste cutting fluids, cutting fluids have serious pollution problems, which pose challenges to global carbon emissions laws and regulations. However, the current research on cutting fluid and its circulating purification technique lacks systematic review papers to provide scientific technical guidance for actual production. In this study, the key scientific issues in the research achievements of eco-friendly cutting fluid and waste fluid treatment are clarified. First, the preparation and mechanism of organic additives are summarized, and the influence of the physical and chemical properties of vegetable base oils on lubricating properties is analyzed. Then, the process characteristics of cutting fluid reduction supply methods are systematically evaluated. Second, the treatment of oil mist and miscellaneous oil, the removal mechanism and approach of microorganisms, and the design principles of integrated recycling equipment are outlined. The conclusion is concluded that the synergistic effect of organic additives, biodegradable vegetable base oils and recycling purification effectively reduces the environmental pollution of cutting fluids. Finally, in view of the limitations of the cutting fluid and its circulating purification technique, the prospects of amino acid additive development, self-adapting jet parameter supply system, matching mechanism between processing conditions and cutting fluid are put forward, which provides the basis and support for the engineering application and development of cutting fluid and its circulating purification.

123 citations

Journal ArticleDOI
TL;DR: In this article , a comprehensive review and critical assessment of the existing understanding of electrostatic atomization MQL is provided, which can be used by scientists to gain insights into the action mechanism, theoretical basis, machining performance, and development direction of this technology.
Abstract: Metal cutting fluids (MCFs) under flood conditions do not meet the urgent needs of reducing carbon emission. Biolubricant-based minimum quantity lubrication (MQL) is an effective alternative to flood lubrication. However, pneumatic atomization MQL has poor atomization properties, which is detrimental to occupational health. Therefore, electrostatic atomization MQL requires preliminary exploratory studies. However, systematic reviews are lacking in terms of capturing the current research status and development direction of this technology. This study aims to provide a comprehensive review and critical assessment of the existing understanding of electrostatic atomization MQL. This research can be used by scientists to gain insights into the action mechanism, theoretical basis, machining performance, and development direction of this technology. First, the critical equipment, eco-friendly atomization media (biolubricants), and empowering mechanisms of electrostatic atomization MQL are presented. Second, the advanced lubrication and heat transfer mechanisms of biolubricants are revealed by quantitatively comparing MQL with MCF-based wet machining. Third, the distinctive wetting and infiltration mechanisms of electrostatic atomization MQL, combined with its unique empowering mechanism and atomization method, are compared with those of pneumatic atomization MQL. Previous experiments have shown that electrostatic atomization MQL can reduce tool wear by 42.4% in metal cutting and improve the machined surface R a by 47% compared with pneumatic atomization MQL. Finally, future development directions, including the improvement of the coordination parameters and equipment integration aspects, are proposed.

102 citations

01 Jan 2004

17 citations

Journal ArticleDOI
10 May 2021-Energies
TL;DR: This article describes the issues related to the analysis of the reliability-exploitation of power supply systems in transport telematics devices (PSSs in TTDs), and addresses the issue of determining CQoPS factor.
Abstract: This article describes the issues related to the analysis of the reliability-exploitation of power supply systems in transport telematics devices (PSSs in TTDs). This paper characterizes solutions, which are applied in supply systems, and describes a PSS in a TTD from a main source and a standby one. This enables determining the dependencies denoting the probabilities of the system staying in full ability state, safety threat state, and safety unreliability state. A quality analysis of the PSS in TTD was conducted, and the indicator value of the supply continuity quality was evaluated. This indicator allows the demonstration of continuity quality of power supply (CQoPS) dependency on many quality dimensions, not just reliability. An example demonstrates the calculation of CQoPS factor for both the main and the standby power supply, employing three observations, each influencing the quality. The presented considerations in the field of quality and reliability-exploitation modeling of a PSS can be applied as well in other public utility facilities (including those classified as critical infrastructure). The character of functions performed by critical infrastructure facilities demands an operating continuity of these systems at an appropriate level. The co-first authors of the article once again address the issue of determining CQoPS factor, this time on the basis of modeling using mathematical evidence. TTD is an example in this article, because the presented methods can be used in any kind of system, especially in the power source of critical systems.

16 citations

Journal ArticleDOI
13 Jan 2022-Symmetry
TL;DR: In this paper , an analysis of the operating conditions of traction drives of electric locomotives with asynchronous traction motors was carried out, and the starting characteristics of the traction drive were obtained for various control methods both in normal and emergency modes of the drive.
Abstract: The analysis of operating conditions of traction drives of electric locomotives with asynchronous traction motors has been carried out. It was found that during operation in the output converter of an asynchronous motor, defects may occur, which leads to asymmetric modes of its operation. Models of a traction drive of an electric locomotive with asynchronous motors with scalar and vector control of the output converter are proposed, taking into account asymmetric operating modes. As a result of the simulation, the starting characteristics of the traction drive were obtained for various control methods both in normal and emergency modes of the drive. For the drive-in emergency mode, the following cases were investigated: the balance of the converter output voltages and the turn-to-turn circuit of 10% of phase A winding of the motor stator; imbalance of the output voltages of the inverter and an intact motor; imbalance of the output voltages of the converter and interturn short circuit of 10% of phase A winding of the motor stator. Comparison of the simulation results have shown that in emergency modes in the traction drive, the torque ripple on the motor shaft in the drive with vector control is 13% less, and in scalar control, the phase current unbalance coefficient is 22% less. The results of this work can be used to study the influence of the output converter control methods on the energy efficiency indicators of the traction drive of an AC electric locomotive.

14 citations