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In this article, with the help of software, the relationship between the structure of the material of the brake pad and the temperature distribution of thermal stress on it is established. Spatio-temporal distributions of thermal stresses were analytically determined for the surface layer of the friction element based on the model of a three-section brake pad with non-fixed edges. At present, shoe brake is widely used for freight trains. It converts dynamic energy into thermal energy using the friction between the pads and the wheel, and then dissipates the thermal energy through a heat exchanger. This process includes heat transfer, design features, mechanical characteristics, material properties and other. The article pays special attention to the brake pad pressure, braking mode, brake pad material and other factors. Modeling of thermal effects is the most important in the design of vehicle parts and assemblies. Thermal research is an important step in the study of braking systems namely railway vehicles, where it is necessary to breakе large masses, since the thermal load on the braked railway wheel prevails compared to other types of loads. In this paper, the thermal stress on the friction element of the shoe during braking is investigated. In frictional braking, the process of friction between the brake pad and the wheel occurs at the points of actual contact. The heat flow from the points of actual contact spreads over the entire geometric area of the block.

The article considers the current situation regarding the organization of control over the use of traction and energy resources of JSC «Russian Railways». The main provisions of the proposed method are stated. The influence factors on the specific electric power consumption of electric locomotives of series 2ES6 and VL10, as well as the evaluation of the quality of the constructed models of multiple nonlinear regression were estimated. New scientifically grounded technological solutions and developments are proposed that allow to reduce the specific consumption and unproductive losses of electric energy within the boundaries of the railway accounting areas.

The subject of research is the evaluation of the effectiveness of different modes of energy-optimal control of the movement of a freight train of a unified mass by AC freight electric locomotives of the Uz-El series with asynchronous electric motors on the flat section of Kokand - Andijan of the Uzbek railway. Purpose of the study: substantiation of the main performance indicators of electric traction locomotives, taking into account the given traffic schedule, using various options for the optimal mode of controlling the movement of a freight train with a unified train mass on a real flat section of the Uzbek railway. The methods and methodology of the research are the theoretical foundations of locomotive traction, the mathematical theory of optimal object control, as well as the C # programming language (C Sharp) with the development of mock-up applications in the Microsoft Visual Studio 12.0 programming environment.As a result of the study, energy-optimal curves, kinematic parameters of the movement of a freight train and parameters of the main indicators of the energy efficiency of the investigated electric locomotive for different options for traction calculation on the real flat section of Kokand - Andijan of the Uzbek railway were obtained. The obtained kinematic parameters of the movement of freight trains with a unified mass of the train and the parameters of the efficiency indicators for the use of the studied electric locomotives can be used in the Kokand locomotive depot, which will allow developing regime maps for driving freight trains by these electric locomotives, depending on the level of complexity of the track profile and various conditions for organizing rail transportation of goods.

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.

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 article describes how the inclination angle of a pole affects the position of contact wire relative to the level of the rail head. It is proposed to take into account a change in position of supporting constructions on the static parameters of catenary in high-speed Railways.

In article possibilities of decrease in number of not selective shutdowns of high-speed switches by use of the relay - the differential shunt are described at full removal of a package of steel on a branch of smaller section. Results of experimental evaluation of the work of the relay - the differential shunt are given at full removal of a package of steel in a branch of smaller section and its trial operation. Conclusions are drawn on earlier undescribed property of the relay - the differential shunt, at full removal of a package of steel on a branch of smaller section - with increase in speed of increase of current, the considerable time lag of operation of the relay appears.

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 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.

One of the ways to increase the capacity of railways is to use long-distance freight trains with a distributed traction system. In order to reduce the influence of the human factor, it is advisable to use automatic speed control systems on the locomotives of such trains, that take into account the transients occurring in the train. Determination of the longitudinal forces that occur in the train can be carried out by using either a reference mathematical model of the train, or pre-calculated dependencies of these forces on the parameters of the train movement. The second method allows you to simplify the structure and improve the performance of automatic control systems.

The paper discusses the use of automated electricity metering systems to control parameters of the traction power supply system in terms of speed and heavy movements. As the main control system offered an automated system for monitoring energy efficiency of transportation process. The results of testing of the system considered in the measurement example, the boundaries of the active area of railways DC Shalya - Podvoloshnaya Sverdlovsk railway.

The traffic speed increasing on the railways makes strict requirements to the supporting and supporting structures of the contact network, as well as to the parameters and indicators of the contact suspension. The presence of dry friction in the cantilever attachment points indicates a negative effect on the accuracy of adjusting the wires of the contact suspension and on its parameters. The article presents the results of studies of the dry friction value in the console fastening points depending on the type of the contact suspension and suggests a method for reducing friction in the console attachment points. The results of calculations of the effect of friction in the console attachment points on the tension variation along the length of the anchor section are presented.

This article is about technical and economic indicators of the operation of freight locomotives at the ranges of Russian Railways. The most attention is paid to such indicators as train mass, fuel consumption, technical and district speed. There is an analysis of technical and economic indicators during the period from 2010 till 2019. Based on the analysis of technical and economic indicators in the real mode of operation of freight diesel locomotives it's presented calculation of dimensionless train mass coefficients, fuel efficient use, district and technical speeds. The presented calculation fully characterizes as well using degree of technical and economic characteristics of diesel locomotives in of power and time as the effectiveness of system organization in their operation. To know the operating modes of diesel-generator sets of diesel locomotives in train work is source material for the analysis of technical characteristics of locomotive power equipment and making recommendations on their optimization in relation to operating conditions

The article outlines methodological approaches to assessing the effectiveness of measures aimed at improving the efficiency of recuperative braking application and the use of energy recovery. An example of calculating the energy efficiency of recuperation on a double-track section of direct current is given. The analysis of the influence of changes in such parameters of the section as technical and district speed of freight trains on the efficiency of energy recovery. The article presents the results of estimating the energy recovery components that form the economic efficiency of recuperation, and describes the approaches to predicting the change in this efficiency, depending on the change in the influencing factors.

In article temporary characteristics and results of the analysis of operation of the relay - the differential shunt are considered at full removal of a package of steel on a branch of smaller section. Conclusions are drawn on opportunities of its application at pass by the electrorolling stock of the isolating interfaces. The method of the choice of settings of the relay - the differential shunt, considering time delay at its operation is offered.

The development of railway transport is currently impossible to imagine without the use of mathematical models and algorithms. Consider the increase in speeds, reduction of travel time, while minimizing costs, is possible only with the qualitative and full use of the mathematical apparatus. The use of information technologies makes it possible to take an effective decision in the development of a project for the reconstruction of a railway line. The current state of the theory of railway transport is characterized by the presence of a developed system of mathematical models and algorithms for analyzing various features of railways. This opens up possibilities for building an approach to the problems of searching and optimizing design solutions on a mathematical basis, with the reduction to a minimum of costly and time-consuming physical modeling procedures. One of the main tasks that are set for the railway transport in the near future is to increase the speed of trains on existing railway lines with the use of computer technology (computer-aided design). The article deals with the problems of technical reconstruction of the railway plan to increase the speed of train movement. The urgency of the use of computer mathematical methods for the development of an optimal plan for increasing the speed of trains. A pair of mutually dual problems of optimal reconstruction of railway curves to increase the speed of trains with minimal capital investment is considered. As methods for solving the problems posed, the following methods were proposed: the method of steepest descent, a modified method of dynamic programming (the Cattell method), the method of indefinite Lagrange multipliers. The expediency of using each method to solve the problem is indicated. The considered methods allow to implement a number of computer-aided design procedures for the reconstruction of the railway plan.

The most important task of the Russian Federation's energy strategy is the efficient use of energy resources. Rail transport is a one of the major consumers of diesel fuel and electricity, where the major energy consumption is used for traction. Traction energy consumption depends on a number of operational factors, including the characteristics of high-speed trains. The article is devoted to the designation of ways to assess the impact of changes in the coefficient of the precinct speed of freight trains on the change in specific energy consumption of locomotives. It is concluded that the calculation influence coefficient use indicators of locomotives, including the coefficient of the precinct speed must be performed for each of the structural units and analyzed the calendar period. Proposed by the authors for this formula is included in the methods of analysis and forecasting of energy resources consumption for traction trains introduced on the Russian train system in 2015.

Increasing speeds on existing railway lines is one of the main challenges facing the Belarusian railway. Through the territory of the republic there are two transport corridors connecting Russia and Western Europe, as well as Ukraine and the Baltic countries. In all of the above countries, the increase in speed on the railways is very fast. Belarus can not stand aside. However, to increase the speed, it is not always enough initial information. To identify the necessary data, methods of decision theory are used. The integral probabilistic criterion method (CPI) allows one to substantiate the road parameters necessary for introducing high-speed traffic on existing lines. The proposed method of decision-making on the choice of technical parameters and equipment of the line, taking into account the uncertainty in the re-design for the high-speed movement of passenger trains. The initial data for determining the CPI is a risk matrix or a matrix of particular criteria. When using the risk matrix for each design decision option i, the dependences of the expectation of losses on the probability of realization of the design conditions p varying in the range from 0 to 1 are compiled. In the article on the proposed methodology, the reduced costs for the variants of design solutions are determined under all possible design conditions. Using these costs, a matrix of private criteria and a risk matrix are formed. A comparison was made of the design decision options for the integral probabilistic criterion, using which the recommendation of choosing the option is unambiguous and is accompanied by a quantitative assessment, which facilitates the task to the decision maker.