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The article sets out the methodology of the study of a rigid mathematical model describing locomotive wheel and rail interaction, taking into account the hypothesis f. Carter. On the basis of the application of the theorem N.A. Tikhonova derived the differential equation for determining the rate of slippage of wheel pair on Rails. Determine the time dependence for the establishment of a process of kinematic slippage of wheel pair on Rails from the wheel speeds and locomotive, from inertial characteristics of trains and the wheel, as well as the coefficient of creep, annexed to the torque of wheel pair and the State of the surfaces of the Rails.

The evaluation of the stress state of the elastic pad rim wheel set new design and the substantiation method of its calculation.

The aim of the work, the results of which are presented in this article, is to identify effective parameter of the heating process in the collector-brush unit of DC traction motor. The article suggests a detailed equivalent thermal equation of DC traction collector-brush unit. An experiment in a laboratory according to the theory of experimental design in the central rotatable terms of the second order are held, and the analysis of the results are presented. A method for processing the results of thermographic study of the machine is described. The regression equation, reflecting the degree of influence of the mode parameters of the machine on the intensity of the heating area of traction motor collector-brush unit, is compiled. The correct use of mathematical apparatus is confirmed by quantitative calculations Student's criteria assessing the significance of the coefficients of equations and F-Fisher criterion within the 5 % significance level. The results can be used to supplement the methods of DC traction motors and collector-brush unit technical condition diagnostics.

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 clause the organization and perfection of process of repair axle box units of a rolling stock by results of diagnostics is considered. The diagnostic model of object, and also a technique of perfection of repair on an actual condition with application of technical diagnostics and the analytical means, based on concept ТРМ is resulted.

The article presents the results of experimental researches of process of commutation in traction DC motors. In order to generalize the results of tests of low power engines for electric locomotive’s traction motors, belonging to high power engines, by using the theory of similarity and dimensions we defined the ranges of varying parameters of the operation mode in the experiments. In result of the conducted researches proved the effectiveness of the parameters of laws of distribution of intensity sparking to improve the reliability of the test as low power engines and high power engines.

The urgency of the task of creating test signals of vibration. Described possible ways of implementation of the test vibration signals. A method of forming a test signal by adjusting amplitudes of the individual harmonic components of the vibration signal. Showing the results of modeling. Shows the possible effect of using the proposed method.

In article advanced techniques of laboratory and natural aerodynamic researches of a pantograph and its elements are considered. It is specified that carrying out modeling by means of computational fluid dynamics methods doesn't allow to replace pilot studies completely now. Need of correction of the received results because of influence of change of density of the environment during experimental studies locates. Density of the environment is offered to consider it as an integrated indicator. The main methods of measurement of density of the environment are given, their advantages and shortcomings are listed. The conclusion is drawn that it is most expedient to use ultrasonic measuring instruments to control of an indicator of density. The principle of operation of these measuring instruments is described. The example of use of an advanced technique of laboratory researches of the aerodynamic device for regulation of force of contact pressing of a current collector is given. Researches were conducted for device wing angles of rotation from zero to fifteen degrees with an interval of five degrees. After that aerodynamic characteristics of a wing of the aerodynamic device were under construction and comparison to results of modeling was carried out by means of a computing hydraulic gas dynamics them. The results received in OSTU laboratory well were correlated with results of computational fluid dynamics modeling that testified to adequacy of the applied technique.

The wheel-motor unit of freight electric locomotives is characterized by the dynamic effect of a wide range of the disturbances due to irregularities in the track. This is one of the main reasons for the high damageability of the gear casings, observed recently, and it indicates the need to improve its design. The proposed design changes for the casing should be directly related to the assessment of the level of the dynamic loading during its operation. The results of the numerical and experimental determination of the natural frequencies of metal casings of traction gear used on electric locomotives of the VL85 and 2 (3) ES5K series are presented. For the numerical determination of the natural frequencies of the enclosures, a modal calculation of the solid model of the enclosure in the Ansys Workbench software environment was performed using the finite element method. A comparative analysis of the distribution of deformation fields in the sidewalls of the casing for a casing that is not fixed to the traction engine and rigidly fixed is carried out. For the experimental evaluation of the natural frequencies of the gear casings, a vibration transducer fixed on the casing was used; the method of excitation of vibrations with a single blow was used to excite vibration. As the result of the experiment, the peak values of vibration acceleration were revealed at some frequencies, which testifies to the emerging resonance phenomena for the casing, and the values of such dynamic parameters for the casing design as natural frequency, Q-factor of the oscillating system, logarithmic damping decrement, relaxation time were obtained. The values of the natural frequencies of the gear housing are obtained by solving a system of Lagrange differential equations of the second kind. The mathematical model of the considered mechanical system created for this purpose takes into account the elastic nature of the casing attachment to the traction motor. The values of the frequencies of the natural vibrations of the gear housing obtained make it possible to evaluate its dynamic loading at the frequencies close to the resonant ones.

The deterministic evaluation of the durability of railway rolling stock structures according to fatigue safety factors, established by regulatory requirements, does not fully take into account the random nature of loads that cause the accumulation of fatigue damages, the operation rate (operating time), does not allow to evaluate the operating life and its depletion over the service lifetime. At the same time, with the development of heavy and high-speed traffic, as well as due to the introduction of technical regulations, the task to evaluate and substantiate the assigned service lifetime and operating life of railway vehicles are becoming more important. The subject of the study, the results of which are presented in this article, was the fatigue strength of elements of locomotive basic parts. The purpose of the work was the prediction of their limit state by the operating life of critical elements. In the present work, design and experimental studies have been performed with running dynamic and strength tests of the locomotive in the entire range of operating speeds of its running, determining the stress-strain state of structures using strain-gauge methods, calculating safety factors with the probabilistic estimate of the fatigue strength of parts. According to results obtained, the influence of the operation loading performance on the fatigue strength margin and its depletion during the element operating life is shown. According to the results of this work, it can be concluded that main indicators of the strength, operating life and service lifetime of the locomotive make it possible to compare and link their key parameters for the subsequent analysis, substantiation, rating and control of safe operating life of railway equipment.

The subject of the study is the fuel utilization system of a diesel power plant as a diesel locomo-tive or other vehicle main lead, which is a complex technical system consisting of actual diesel in-ternal combustion engine, fuel lines and low pressure fuel processing and high pressure line includ-ing various elements of liquid fuels consumption dosing and control. The aim of our study was to analyze the system functioning, to determine the dynamic proper-ties and the nature of changes in the internal parameters of the system as a whole. To achieve the goal the system analysis methods were used. The processes of complex technical system operation were interpreted by means of the continuous linear stationary deterministic model of the list of others. For this particular model the body of mathematics developed on the basis of linear differential equations with constant coefficients is the most complete one. The chosen mathematical model was presented by us in the first stage in the form of a finite graph as a subgraph of obtained earlier generalized model which had both methodological and theoretical foundation. In accordance with the methodology of the systematic approach the graph model of the diesel power plant fuel utilization system operation was described in relation to major significant factors affecting the system parameters transformation dynamics. Given the complexity of the of fuel ignition and combustion mechanism located in the diesel engine cylinder, the use of the techniques of the modern automated control theory is adopted for numerical processes simulation with the system described in terms of the said theory. The criteria of efficiency, mechanical loads and thermal loads levels were chosen as the fuel utilization system internal state variables. Taking into account the Pareto principle the most important efficiency criterion components were chosen for the analysis; and the system of differential equations of the efficiency dynamics in the form of three balance equations was created. The factual description of the included equations allowed us to derive preliminary qualitative conclusions about the dynamic properties of the internal criteria: controllability, observability and stability of the fuel utilization system. The differential equations system parameters linearizing procedure and the introduction of small deviations allowed us to obtain the dynamic mathematical model of the fuel and air transfor-mation in the diesel engine heat cylinder. As the result of transformations we have obtained the equations presented in the form of the matrices, which allowed us to conclude that the process of the fuel and air transformation in the cylinder is controllable, the system is asymptotically stable, and the process is stochastic with the presence of perturbing parameters influenced by the engine's variable modes of operation. The further research areas have been suggested, and the practical results have been predicted: the creation of optimal (in terms of efficiency) control system with the technical solution in the form of the optimal controller (in relation to fuel consumption).

In this article the generalized results of researches of change of intensity of wear of electrical brushes in the traction motors of electric locomotives. On the basis of the conducted research the author proposes an algorithm to predict the operating life of the brushes, given the parameters of the operation. In order to increase the reliability of the calculation has been developed algorithms, which allow additionally taking into account the effect of the collector’s surface.

The article deals with the issue of using electric power storage systems in railway transport. It is noted that they are used in renewable energy sources and on hybrid shunting diesel locomotives. The possibility of using electric power storage systems to improve the efficiency of using electric power for train traction is indicated. The introduction of electric energy storage systems in the traction power supply system is hampered by high capital costs and the need to strengthen several adjacent inter-substation zones at once. It is proposed to consider the possibility of creating a mobile energy storage system, all the equipment of which will be placed in containers installed on cargo platforms, which will allow such a system to be quickly moved. The purpose of introducing a mobile power storage system is to temporarily strengthen the traction power supply system during a planned overhaul or emergency repair of one of the tracks on double-track sections of the railway. In this case, there is a need for a batch pass of trains alternately in even and odd directions on the same track. The possibility of using a mobile energy storage system is considered on the example of a real section of the railway. For a given schedule of passing train packages, the dependence of the storage capacity taken off from time, the maximum power and the nominal effective energy intensity of the storage system are determined. An estimate of the electricity storage system cost is given. It is shown that more than 70 % of the total cost of the electricity storage system falls on the imported energy conversion subsystem. It is concluded that it is necessary to develop domestic converter subsystems.

The article is devoted to the description of the requirements for the accuracy of control devices and the development of methods to ensure the claimed dimensional accuracy by methods of dimensional analysis. The conditions for ensuring the accuracy of the assembly scheme, the determination of the dimensional chain and dimensional analysis of the dimensional chain during the assembly of the control device, as well as the main causes of errors during assembly and ways to eliminate them are listed. In addition, the consequences of the influence of irregular gaps in the interfaces of the control device parts on the measurement accuracy are presented, various types of assembly dimensional chains are considered, tasks solved when calculating the dimensional chain. The paper presents a compiled dimensional chain of the technological process of assembling a measuring instrument for monitoring the alignment of the inserts of motor-axial bearings of traction electric motors of locomotives, which represents a dimensional chain of the first type and is a chain with linear dimensions and vertically parallel links. The purpose of the work is to substantiate the calculated tolerances and limit deviations of the links of the assembly dimensional chain, providing the required value of the closing link for the proper functioning of the assembled measuring instrument. The paper describes the selection of the closing link of the dimensional chain, the selection of the links that make up the dimensional chain, the calculation of the limiting deviations of the closing link that ensure the required measurement accuracy during operation of the control device and the calculation of the limiting deviations of the components of the links of the dimensional chain by the "maximum-minimum" method. Thus, the article presents a solution to the design problem of dimensional analysis, which consists in determining the accuracy of the component links of the dimensional chain when assembling the control device according to the known calculated tolerance of the closing link and its limit deviations.

Despite significant progress in the development of accounting systems, there is almost universal growth accounting losses of electricity and reduce its quality. Along with the introduction of modern energy efficient electrical problem efficiency of electric energy in the stationary energy sector can be achieved through the implementation of active-adaptive technologies for controlling the operation of compensating devices, controlled means of voltage control, switching and power equipment and diagnosis based on digital technology, including automatically maintain a minimum transmission losses when the load. Management of objects offered no traction electricity consumers based on adaptive technology and hardware-software optimization mode parameters in real time.

The article considers the urgency of the problem of creating an on-board system of diagnosing the technical condition of railway car, the shortcomings of the existing diagnostic tools are indicated. Patent search of electric power sources for freight wagons has been carried out, their features have been determined. The author's design of the power supply device is proposed to diagnose the technical condition of railway car on the trip.

The article is devoted to the improvement of the testing method of current collectors of electric rolling stock considering collision efforts from the overhead catenary. The article discusses the features of collision effects on pantographs of electric rolling stock at high speeds. An analysis of the existing methods for testing collision effects on pantographs in laboratory installations and in linear conditions has been carried out. The analysis is carried out and the drawbacks of the percussion pendulum installation for testing current collectors, described in GOST 32204-2013, are identified, and its characteristics are calculated. The design of a shock stand with smaller dimensions and expanded functionality is proposed, and its parameters and characteristics are calculated. When calculating the characteristics of the test bench, mathematical and computer modeling was applied using the MATLAB Simulink environment. The method of bench collision testing using accelerometers and high-speed video camera. It was established that the proposed test bench retains the full functionality of the test facility regulated by GOST, while having smaller dimensions and wider functionality.

The contact network is one of the most vulnerable elements of the traction power supply system. The prevailing number of events in the power supply sector is connected with the contact network. The article is devoted to the method of contactless diagnostics of the contact network of electrified Railways. The paper proposes to use a method for diagnostics of the contact network based on optical elements, followed by digital data processing and calculation of geometric parameters. This method is characterized by a low cost of the device in contrast to analogues and high accuracy of calculation. The analysis and selection of optimal installation locations for optical devices is given. The method of contactless diagnostics of wires of the contact network of electrified Railways is presented.

In the article the author presents a logical-linguistic model, providing a sufficient depth and completeness of diagnostics with fulfillment of all required testing instructions and standards. Diagnostic features for every required testing were determined in order to build the suggested model. The results of a diagnostic model development were applied and successfully tested on various types of electrical sections

The article proposes a numerical-analytical method based on the boundary element method (Method of Boundary Elements Technology), which used to assess of change patterns of temperature fields in the working fluid in hydro-friction vibration damper telescopic view when the ambient temperature changes. This method takes into account the physico-mechanical properties of the working fluid and the effect of corrosion pouring temperature, ambient temperature, the speed of electric rolling stock and the working liquid filling height.

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 %.

The article devoted to results of the longitudinal multiplicative perturbation effect from railway track in relation to rolling stock.There is the technique for finding of difference type Raman resonances areas,which based on the theory of division in slow and fast components for motion of dynamic system.It proves a fact that the RMS-velocity for motion of the train is not a specific numerical value,but that is an area for which the width depends on the multiplicative factor driving

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 article discusses methods in evaluating the current settings for turning on and off the second converter unit when introducing power backup systems for DC traction substations. The analysis of the advantages and disadvantages of existing methods. The algorithm for calculating the current settings. A comparative analysis of the operating currents of the automation of the converter unit is carried out on the example of traction substations of the current section of the West Siberian Railway.

The article describes the general principles of the computational model of the traction power supply DC Railway to assess the potential energy recuperative braking, as well as ways of approbation the resulting model to determine its adequacy.