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In article aerodynamic properties of SSS87 current collectors intended for the high-speed movement of the electric rolling stock are considered. Spectra are presented of the flow for different shapes of the contact plates. The solution of a problem of modeling of flow of the contact plates of the current collector with the air environment is reached by application of methods of computing hydrodynamics (CFD) the aerodynamic coefficients necessary for calculation of aerodynamic characteristics Are defined. Aerodynamic characteristics of current collectors are constructed.

In accordance with the long-term development program of JSC Russian Railways until 2025, it is planned to increase the level of economic connectivity of the territory of Russia by expanding the network of high-speed and high-speed transportation. This involves not only the construction of new high-speed highways, but also the modernization of the structures of individual components of rolling stock, as well as the introduction of energy and resource-saving technologies. The use of contact elements with an extended service life is one of the most economical and least costly ways to ensure reliable, economical and environmentally friendly transmission of electricity to rolling stock. An increase in the service life of the current collector element can be achieved, among other things, by reducing wear by the correct selection of contact pair elements, both from the point of view of their tribocompatibility and the ability to ensure high quality current collection. A methodology for conducting experimental studies of contact pairs of current collection devices has been developed and successfully tested at OSTU, which involves bench tests for each pair of contact materials “contact insert - contact wire” in order to determine their optimal combination to reduce wear and increase resource. Estimation of the amount of wear and prediction of the life of the elements of the contact pair is carried out including using mathematical models. However, the use of existing models for predicting wear under conditions of high-speed movement is not accurate enough due to the lack of consideration of the aerodynamic effects and the speed of the rolling stock on current collection processes. This article discusses the improvement of the mechanical component of the wear model of the elements of contact pairs of current collection devices in high-speed conditions. The graphs of the mechanical wear of the contact elements are obtained experimentally and as a result of calculation by a mathematical model. The analysis of the graphs allows us to conclude that it is possible to use an improved mathematical model for modeling the mechanical component of the wear process of the elements of contact pairs with a maximum error value of not more than 5 %.

In the article suggests a changing the algorithm of the rectifier-inverter converter electric locomotive VL85. This will allow the individuallyto regulatevoltageon traction engines. In this case willpreserve a singlecentralized system ofcontrol of allelectricconverters. The proposed solutions may be used for liquidation started spinning of wheel locomotive. Tractive force the remaining wheelsets will not decrease.

The analysis of the influence of the organization of the formation of United freight trains on the throughput capacity of railway sections has been carried out. The results of electrical calculations of the 3.0 kV dc power supply system of 3 sections of the Sverdlovsk and South Ural railways are presented when controlling the speed of trains from 50 km / h to 100 km / h with various locomotives while passing two single and one connected cargo trains using the system of contactless automatic voltage regulation in the contact network, allowing to assess the throughput capacity of the three sections. In the course of the calculations, the developed refinement method was applied using the correction current factors KIxx and KIst. Proved the need for their use in electrical calculations.

The contact line is a special kind of power overhead line with multiple electrical connections of wires, which form a complex topology of the linear electrical circuit. Analytical models simplify the real topology of the contact line and it limits their functional application. It is possible to take into account the topology of contact line when using tools of computer simulation, but it entails complicating the computational algorithms of the model. The aim of this article is to determine the conditions for the application of current distribution models and the development prospects in this area. The article describes the existing models for calculating the current distribution in DC contact line: a model of natural current distribution, linear analytical models, model with an infinite number of droppers, a model with a direct application of Kirchhoff's circuit laws in matrix form, and a finite element model. The article contains the main provisions and calculation capabilities of each model. Contact line KS-250-3 acts as a calculation catenary for the comparison of current distribution models. You can use the results of the article to select the optimal design distribution model for the design of the contact line, thermal analysis, current-carrying capacity calculation, identification and elimination of «weak point».

The existing protection does not provide protective potential of traction substation grounding grid for the entire period of operation. This disadvantage is removed by improving of automatic drainage unit. The basis of the automatic drainage system is automatic control of drainage current by changing the pulse width of current. This method of current control allows the defined potential remain at the set value. The article presents a functional diagram describing the basic units of the improved automatic drainage unit. The results of the automatic drainage unit tests illustrate that the automatic drainage unit limits the current flowing through the grounding grid to the traction substation, allowing the potential remain at the set value Improved automatic drainage unit has great advantages in relation to existing and operated drain units at this moment and it can be recommended for introduction to the electrification infrastructure of the railway industry. Also this automatic drainage unit can be used for protection of other metal underground structures such as pipelines and other metal structures influenced by stray currents.

In the article the finite element model of the electrical contact pin wire - collector strip, which takes into account the complex interaction of electric and thermal processes. As the contact wire is selected worn MF-100, the current collection plate - two brands VJZ-metal and graphite. Microgeometry the body surface at the contact point is obtained based on the model of Greenwood - Williamson. It was considered the two extreme cases of possible contact between the contact wire to the plate. The results were analyzed and compared with the known experimental data. Calculated at what proportions contact force and contact current due to burnout occurs spark or arc. Identify ways to improve the model.

The article describes the design of a universal measuring pantograph, designed to obtain during the test trips sets of accurate and adequate information on the quality of current collection due to the possibility of modeling parameters and characteristics of advanced domestic and foreign current collectors, mounted on a modern electric rolling stock. Presented the results of his testing at the West-Siberian railway.

A mathematical model of thermal processes (dynamic) contact current collector with contact suspension (in motion), which allows to estimate the temperature distribution of heating the current collector during movement. The experimental evaluation of the proposed cooling device performance is given. The thermal model of the current collector in motion mode has been verified.

The purpose of this article is to analyze the voltage drop in the contact network caused by poor-quality operation of an alternating current electric locomotive when passing heavy trains. Heavy-haul traffic is considered today as a valid and necessary tool for increasing weight norms and increasing the throughput of railway sections. The article provides statistics on the passage of heavy and connected trains on the Krasnoyarsk railway for 2019 and 2020. For the effective use of heavy traffic, it is necessary to solve a number of problems, one of which is to reduce the voltage in the overhead network when passing heavy trains, this negatively affects the speed of the train along the haul, the conditions for cooling the power equipment of the electric locomotive deteriorate, etc. As a result of the analysis of the operation of the thyristor rectifier-inverter converter, a number of disadvantages were revealed. The reason for the low power factor of the electric locomotive lies in the use of an outdated element base based on thyristors, their closure is carried out only in the next voltage half-cycle, long-term switching and a large opening angle of thyristors leads to a significant reactive current in the contact network. Based on the analysis the voltage losses at the current collector, it was concluded that it is necessary to reduce the duration of the switching process of the arms of the rectifier-inverter converter, in which a short circuit occurs in the secondary winding of the traction transformer. An alternative version of the converter based on fully controlled semiconductor devices - IGBT transistors is proposed. The ability to open and close at any time of such elements allows you to minimize the phase angle and increase the power factor. Due to the almost instantaneous switching of transistors, the distortion in the contact network is minimized.

In article the reasons of shutdowns of high-speed switches of a direct current are analysed and distribution of the disconnected currents is received. Such numerical characteristics as population mean and a mean square deviation of function of distribution of the currents which are disconnected by the high-speed switch are considered. The hypothesis of distribution of probability of refusal in operation of the switch is checked. Conclusions are drawn on applicability of the given calculation methods for definition of admissible number of shutdowns of high-speed switches on sites of traction network of a direct current.

The purpose of the article is to consider the issue of calculating and selecting the settings for the operation of the short-circuit switch KZKS-3.3 when organizing the protection of a direct current contact network in emergency mode. The shorting circuit is measured by the voltage module. When the triggering conditions are met, it is the voltage module that collects the circuit to turn on the switching device of the short circuit. The important question is to choose the optimal installation location of the short-circuit switches and the voltage trip settings. The initial information necessary for the calculation of the settings is determined. The calculation procedure and equivalent circuits for the most common power supply circuits and sectioning of the contact network are given. For current protection of high-speed circuit-breaker feeders, contact formulas are given for determining the sensitivity zones. To select the optimal installation location of the short-circuit and select the voltage pick-up setting from the allowable range, a potential diagram of the contact network section is constructed. The analysis based on the potential diagram allows us to conclude that the organization of protection of the contact network in emergency mode using short circuits is effective.

The article deals with the analysis of methods for obtaining statistically reliable data on contact pressure, which are based on the results of inspection trips and data on the design values of the location of the contact wires in the vertical plane andin the path plan. A method for calculating contact pressing with artificial neural networks is proposed. The methods of obtaining statistically reliable data on the contact pressing of current collectors of electric rolling stock without the need for direct measurement, based on the video image of the current collection process and analysis of external factors (weather, operational) accompanying the interaction are considered.

The work is devoted to the consideration of the possibility of using composite materials with an aluminum matrix in the design of electric transport pantographs. Currently, there is a tendency to increase the speeds of electric transport. This fact requires reliable and high-quality current collection, which can be achieved by reducing the mass of the current collector design, including through the use of composite materials. The possibility of using composite materials in parts and assemblies of current collectors operating under conditions of increased current loads and at high speeds of movement and the mechanical characteristics of the traditional ones used in the carriage design and the composite materials proposed for use are analyzed. The design of a carriage of high-speed electric rolling stock has been developed, in which an aluminum matrix composite material was used as a structural material. Statistical modeling using the finite element method in the SOLIDWORKS Simulation software package was performed. Comparison of the strength characteristics of carriage assemblies made of traditional materials and aluminum matrix composite showed the possibility of reducing their weight in the case of composite use without reducing the strength of structural elements. The static characteristic of the carriage in which the composite material was used coincides with the static characteristic of the carriage made of traditional materials, which confirms the possibility of using an aluminum matrix composite without making significant changes to the carriage design. To evaluate the dynamic characteristics of the composite carriage and its effect on the dynamic characteristics of the pantograph, modeling was carried out using the methods of multibody modeling of SOLIDWORKS Motion. The obtained simulation results indicate an improvement in dynamic characteristics when using composite materials, which has a beneficial effect on the reliability and quality of current collection.

The analysis of wave processes in the system including electric transmission lines, traction substations, AC traction network and electriclocomotives is necessary to accurately assess to energy performance of its work. This system contains concentrated and distributed parameters, consequently the analysis of such a system is difficult and the rolling stock which is also a part of this system represents a dynamic load. The proposed mathematical model of the alternating current traction power supply system allows us to consider electromagnetic processes at its various points taking into account wave processes.

The paper is devoted to the calculation of the electrical quantities distribution in the system of three conductors. The first conductor is located on the surface of a uniform soil and the other two conductors are located at depths of h and h . As result, analytic expressions of current, potential and leakage current density in the first underground construction with considering the influence of the second construction was obtained. The influence of second construction increases the value of electrical quantities in the underground construction. The analytic expressions were obtained using Fourier transform method. The analysis showed the influence of the leakage current and insulation resistance of the second construction on the electric quantities distribution in the first construction

Various converters are operated at electric railways traction substations whose rectifiers design includes plug-in power rectifiers and pill ones. Such a variety of rectifiers design causes the problem of the power supply reliable operation unavailability both of volumes and of quality information concerning the characteristics and diagnostic parameters of power semiconductors rectifiers. For a possible prediction of the diodes and thyristors proper operation, new instruments as well as simple technologies of the preventive diagnostics, correspondent to the state and industry standards and instructions should be developed. One of the most accurate methods to determine not only the serviceability of rectifiers but also to forecast their wear - life, is the diagnostic method of recurrent peak backward current. This method is the basis for the design of a peak backward current meter which is used on the Western-Siberian railway. Using this device the screening of about thirty thousand rectifiers was carried out which resulted in the sorting of out-of-work rectifiers, predicting long term rectifiers conditions. The statistical analysis of the research allowed to determine the number of measures to improve the reliability of traction substations converters.

Single-phase transformer with an additional tap at the middle point of the secondary winding is a very common element in the various electrical circuits, including on-board electric rolling stock. A typical case is powered from the transformer zero full-wave rectification circuit. The aim of the article is to provide a detailed description of the computer model developed by the author of said transformer, built on the basis of a combination of circuit and operational design principles. The proposed model can also be used to describe the process in a single-phase two-winding transformer without additional tap, given the possible connection group I / I-6 or I / I-0. Connection groups can be considered individually for each half of the secondary winding in case of using of additional tap. Shows an example of embedding the transformer model in a more complex computer model of the electric traction DC motors excitation current stabilization system, which includes a computer model of a saturable reactor, thyristor rectifier, system of pulse-phase rectifier control and control loop with a proportional-integral current regulator and boost nonlinearity. Obtained during the simulation graphics excitation current in the field winding of collector traction motor and its reactive component show that the above system of stabilization of the current and its computer model of functional and successfully fulfill their functions: at the downturn of the armature current excitation current is maintained by the growth of the current make-up of excitation control rectifier. The correct operation and ease of use of the developed computer model of a single-phase transformer with an additional tap at the middle point of the secondary winding is stated.

The article considers an approach that allows to reduce the asymmetry of consumed currents by traction substations of railways from a three-phase power supply system using a compensating device with an asymmetric structure installed at the substation. Reactive currents of the compensating device allow to redistribute between phases of the traction transformer active and reactive power of asymmetric traction load and to receive symmetric load of three-phase power supply system. The theorem is proposed to determine the conductivities and reactive currents of the branches of a compensating device with an asymmetric structure depending on the traction loads. The article presents the calculated expressions, which can be used to calculate the conductivity and reactive currents of the branches of the compensating device for any traction load of the feeders, in which the equivalent load, including the reactive currents of the branches of the device and the currents of the feeder zones will be symmetrical and active. As an example of the application of the theorem and the proposed expressions, a test problem is presented in which the secondary winding of a traction transformer with asymmetric traction load of feeders is considered, the conductivity of the branches of the device is calculated. With the use of vector diagrams shows the receipt of a symmetrical system of currents of the secondary winding of the traction transformer. Mathematical expressions allowing to realize the necessary law of regulation of reactive currents of the device are given. The necessary ranges control of reactive currents of the compensating device on traction substation on the set probabilistic laws of change of traction loadings are defined. Various options for the practical implementation of a compensating device that will provide the necessary inductive or capacitive current of each branch are considered.

The article describes two methods to estimate the rotor speed of the induction motor using special spectral components generated by the engine design. After you search for these components is possible to estimate the rotor slip. The aim is to compare these methods under different engine loads and to determine the most accurate method. The result is program algorithm for determining the rotational speed of the rotor of an induction motor, which can be used for a variety of practical tasks that require precise definition of speed, but there is no any access to moving parts to install the speed sensor or the use of sensors is undesirable revolutions.

The technique and algorithm of definition of consumption rates of materials on the current maintenance of a way depending on freight density, the passed tonnage, the plan and a profile of sites of a way, axial loadings of a rolling stock is given. Standards are developed on the basis of the analysis of the existing normative documents, statistical data from forms of primary accounting of PU-74 of the consumption of materials, annual reports of linear sites and other sources. Depending on service conditions standards are determined by analytical dependences and the correcting coefficients.

Corrosion processes at various constructive changes of grounding system of traction substation are considered: construction of new cable lines, expansion of the territory of substation, etc. Calculation of corrosion processes of the grounding system consisting of three electrodes is carried out: steel in concrete, the metal gauze in soil, a steel vertical electrode in soil. Results of calculations are presented, the analysis of corrosion processes is made under various conditions.

The article discusses the assessment of the impact of train schedule on the amount of electricity consumption for traction on sections of DC I-th profile type way. The proposed parameters of the train schedule, influencing the electricity consumption for traction on sections of DC I-th profile type way. The major scheduling options included statistical quantities and parameters characterizing the conditions of the batch passing trains, stop and solid thread schedules for truck-driving. Based on simulation modeling provided the main based on changes in the volume of electric energy for traction on the plot of the traction electric supply system when changing the parameters of the timetable. The dependences of the volume change of electrical energy for traction allow you to evaluate and determine the ranges of the parameters of the graph in which the variation of volume is minimal. in the considered ranges of the parameters of the train schedule, the amount of electricity for the areas of DC with the I-th profile type varies within 1 % with the constancy of other factors..

The mathematical method of calculation of currents of corrosion of two models of grounding models - ekvipotentsialny and nonkvipotentsialny is presented. Soil and electric corrosion of both models is considered. The mathematical method of calculation of sizes of corrosion currents and potentials will allow to estimate a corrosion condition of elements of grounding system of traction substation.

A method for predicting the performance of the current collection with increasing speeds using machine learning is proposed. Methods for obtaining statistically reliable data on the contact pressure of current-carrying electric rolling stock without the need for direct measurement based on design data and analysis of external factors (weather, operational) accompanying the interaction are considered.