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Wearing parts of the cylinder-piston group and crank mechanism is one of the main reasons for putting a diesel engine into repair. Timely detection of the occurrence of intense wear allows you to prevent negative consequences, make timely repairs, eliminate the likelihood of unplanned exit of the locomotive from service. As a result of the study of the intensity of accumulation of wear products in engine oil, a mathematical model has been developed, which is implemented with the use of an artificial neural network apparatus. Its use allows to carry out an operational assessment of the technical condition of diesel engine parts in an in dividing way and to improve the technological process of repairing diesel engines of the D49 type

The wheelset and its components (the axle and the wheel) are subject to technical regulation. Therefore, in order to establish the assigned service life in accordance with TRCU 001/2011 (Technical Regulations of the Customs Union) and the examination frequency taking into account the durability parameters of rolling stock components in accordance with VNIIZhT RD 27.05.01-2017, it is necessary to assess the operational loading obtained from the running testing results, with respect to the part strength characteristics which are calculated during the bench tests. At present, to estimate the stress-strain state (SSS) in various machine-building structures, the strain measurement method is widely used, which allows to assess their performance with high accuracy. However, determining the SSS of a wheelset is not only a difficult task due to the constant rotation and movement of the wheelset relative to the bogie, but also expensive due to the employment of special non-contact measuring systems. Development of a dynamic model using modern software systems allows determination the stress-strain state of the wheelset elements by creating dynamic models as a system of perfectly rigid and elastic bodies connected by strength members and hinges. To confirm the adequacy of the parameters obtained in the simulation, verification is carried out according to the results of running dynamic strength tests. Thus, using the obtained model of the rolling stock and the track it is possible to make life and durability assessment as well as optimize the main rolling stock components. On the example of a freight gondola car model, a diagram of the dependence of dynamic stress amplitude distribution on the frequency of the occurrence in the wheel has been obtained, and considering the results of the earlier bench tests of standard specimens and full-scale wheels the period has been determined for durability from the moment of crack initiation in the wheel up to its fracture, as well as the assessment of the safety factor for durability is given.

This article discusses the improvement of the electrical component of the wear model of the elements of contact pairs of current collector devices under conditions of high-speed movement. The histograms of the electrical wear of contact elements obtained by calculation using the existing and improved mathematical models are presented. Analysis of the obtained histograms allows us to conclude that the calculation accuracy is improved according to an improved mathematical model by taking into account the influence of the aerodynamic effects of the air flow and the speed of the rolling stock.

Introduced on the Russian Railways network monitoring system download the snow train has allowed to identify cases of export volume of the snow mass is much less possible when cleaning railway tracks from snow, which leads to the underutilization of capacity of the snow trains and shunting locomotives and irrational use of fuel and energy resources for operation of rolling stock. The purpose of the work is to consider the fuel and energy efficiency of snow-removal trains and shunting locomotives carrying out their movement and to determine ways to reduce the consumption of fuel and energy resources for the performance of works on cleaning the tracks from snow (in economic traffic). To achieve this goal, one of the structural divisions of JSC "Russian Railways" estimated the volume of snow removal by snow-removal trains, calculated the values of mechanical work performed by locomotives to move snow-removal equipment and fuel consumption by snow-removal trains and locomotives to perform work on clearing snow from the tracks. On the basis of the comparative analysis the conclusion is made on the available reserves of increase of fuel and energy performance of the rolling stock while clearing paths of snow and the technique allowing to estimate the total fuel consumption for snow removal snow plow trains and traction units (locomotives), and ways to improve the power efficiency of snow-removing trains and working with them traction means, such as the use of rolling stock with a rational value of mass and power depending on weather conditions.

The article considers the dynamic processes of the oscillatory system «wagon - way», its mathematical model is formed and its features are established. The analysis of existing approaches to the consideration of the influence of dissipative forces on the stability of rolling stock is carried out, their shortcomings are revealed. When composing dynamic process equations, it is important to proceed from their exact expressions when considering kinetic and potential energy, i.e. to take into account the relationship between generalized coordinates, which will allow us to consider in detail the process of rolling stock oscillations. The zone of autoparametric resonance is found. It is established that dry friction forces do not interfere with parametric resonance. Dynamic equations are compiled taking into account the scattering forces arising in the contact points of the structural elements of the car. The influence of dry friction forces on the critical coefficient of parametric excitation is determined. The areas of dynamic instability of a car when moving along a railway track with different characteristics are determined. The features of the behavior of the system under the influence of dry friction forces are revealed. It is established that dry friction forces do not reduce the amplitude of bouncing and can lead to an increase in lateral pitching vibrations due to energy pumping.

The development of the system is accompanied by the diagnostics of their achievement in the technical system. Using the possibility of identifying defects in nodal technical systems in the early stages of their occurrence in order to timely and promptly anticipate, the emergence of work productivity, identify simple repair time, identify material costs for replacement or deep restoration. Railway transport is also at the stage of a wide identification of various components and parts of the rolling stock. the appointment of diagnostic systems is a locomotive fleet, as a more identified technical unit. Today, the locomotive fleet uses hardware and software diagnostic complexes, microprocessor-based diagnostic systems, on-board and track monitoring systems that cover the entire range of diagnostic data of the main technical units. However, the use of the availability of systems requires constant improvement of the mathematical model of diagnosis. One of the options for choosing diagnostic models is the use of artificial intelligence research methods - sections of artificial neural networks, which, in comparison with the classical polynomial regression properties, are manifested by the properties of extrapolation accuracy and are applicable for predicting the values of diagnostic parameters according to the data that were due to the sampling of an artificial neural network. These characteristics make it possible to predict the development of defects and possible failures safely and accurately to obtain them and obtain an economic result. The paper presents an example of the development of a diagnostic artificial neural network model for diagnosing oil starvation of motor-axial bearings of the wheel-motor block of a cargo mainline electric locomotive of the 3ES5K «Ermak» series. This factor has a low level of reliability, so the use of continuous diagnostics is required, which requires the use of a point in time.

The subject of the research is the power thyristor converter of AC electric locomotives and its influence on the power factor of the locomotive. A new method for increasing the power factor of AC electric locomotives with thyristors power converters is proposed and analyzed. These electric locomotives include locomotives of the 2ES5K, VL85, EP1 series, etc. At the initial of the paper, the existing methods of increasing the power factor are briefly considered and their disadvantage in comparison with the proposed method is indicated. The drawback of existing converters is also analyzed, which consists in the presence of a thyristor opening delay at the beginning of the supply voltage half-cycle. The proposed method implies the modernization of the control circuits of the thyristors of the converter, due to which, at the beginning of the half-period, a control current is spontaneously created on the control electrode by means of the supply voltage. As a result, the thyristors open with a minimum delay after the start of the half-cycle. To verification the effectiveness of the proposed solutions, a computer simulation of the operation of the power circuit of an electric locomotive in the ORCAD program was carried out. Simulation was carried out for two options: a power circuit with standard converters and a power circuit with converters upgraded in accordance with the proposed method. During the simulation, the change in the value of the power factor of an electric locomotive was investigated at different currents of traction motors, zone and angle of regulation. Analysis of the oscillograms of converter various arms currents the revealed that when using the modernized converters, the moment of the end of the network switching occurs earlier than in the standard circuit. There is also no area with negative voltage at the output of the converter at the beginning of the half-cycle. At the end of the paper, the values of the electric locomotive power factor are given under various conditions. These results show that the use of the proposed method increases the power factor of an electric locomotive by an average of 1.2 percentage points.

He method of researching the dynamic properties of the railway crew in the action on it harmonic parametric perturbation, caused by the changing rigidity of the base of the rail, is set out. For such differential equations there are no regular methods of solving them, moreover, their exact solutions are not known at present, so they are used by approaching methods. A two-degree mechanical system with a harmonic parametric perturbation described by a system of ordinary homogeneous differential equations is considered. One of the hard-bone parameters is a function of time and varies from 2000 to 3000 N/m. To calculate the boundaries of dynamic instability (parametric resonance) a method of generalized Hill definers is used, which does not require the introduction of small parameters. The area of interaction of parametrically excited and forced vibrations has been determined.

At this time, an urgent area of development in the field of railway transport is the reduction of operating costs for maintenance and repair of collector traction motors . The analysis of data from the monitoring of new rolling stock shows that one of the elements affecting the reliability during the operation of traction motors is the collector-brush unit. Failures associated with unsatisfactory operation of the collector-brush unit elements reach 30% of the total number for traction motors. At work of traction electric motors there is a continuous process of mechanical, electric and chemical interaction of electric brushes with a collector, leading to deterioration of electric brushes. During the research, the authors proposed a mathematical model to determine the intensity of wear of electric brushes. The paper provides information about developing an approach that allows using the operating data recorded by locomotive on-board parameter monitoring system to determine the service life of traction motor brushes. For elimination of the problem connected with processing of big arrays of parameter values for calculation, in mathematical model of intensity of wear of electric brushes it is offered to divide the received data into intervals with definition of average values and probability of approach for each of them, and also the technique on realization of the offered decision is resulted. The developed approach allows us to eliminate the need for long-term wear tests on traction motors in operation and reduce not only time, but also financial costs. The reliability of the developed method was assessed by comparing the wear values of different types of electric brushes installed on locomotive traction motors in operation with the calculated values.

The article is devoted to assessing the influence of diagnostic parameters for assessing the technical condition of the collector profile of rolling stock traction motors on the value of the mechanical force in the «brush-collector» contact. The results of the experimental studies of the parameters of the collector profile for traction motors EK810Ch of mainline electric locomotives 2ES6 are presented. Four-stage numerical experimental studies were carried out for the following conditions: the first stage - the height differences of the lamellas and harmonics were taken into account; the second stage - the height differences of the lamellas are taken into account without the influence of harmonics (with reduced beating); the third stage - harmonics are taken into account without the influence of differences in the heights of the lamellas (with reduced beating); the fourth stage - harmonics are taken into account without the influence of differences in the heights of the lamellas (with a multiplying factor up to a given beat). Using a mathematical model of brush movement along the collector, a degree of relationship was established between the diagnostic parameters that characterize the state of the traction motor collector profile, with the value of the mechanical force in the «brush - collector» contact. A diagnostic parameter is proposed that characterizes the spread of mechanical force values in the «brush - collector» contact of a traction motor, determined from the ratio of the force of elastic interaction of the brush with the collector and the average value of this force. An analysis of the results of the numerical experiment showed that the contact instability coefficient is largely determined by the value of the standard deviation of the lamella drops and, to a small extent, depends on the values of the harmonic amplitudes. The harmonic composition of the collector profile has practically no effect on the value of the contact instability coefficient at small values of the lamella drops. It is concluded that it is possible to use diagnostic parameters for assessing the state of the traction motor commutator surface to determine possible poor contact between the brush and the commutator. It is proposed to evaluate the quality of repair of collectors of traction motors taking into account the standard deviation of the differences of the lamella.

This article describes the standard field reduction system of traction electric motors of a contactor-resistors type using inductive shunts, its drawbacks are revealed. An improved field reduction system of traction electric motors of an AC locomotive based on IGBT transistors has been developed and proposed. The proposed solution will allow to exclude the copper-containing inductive shunt from the power circuit, while providing reliable protection in non-stationary operating modes of the electric locomotive, as well as reduce electricity consumption for train traction. To prove the advantages of the proposed the field reduction system of traction electric motors, a method of comparative analysis of electromagnetic processes of the mathematical model of the standard and proposed systems of the field reduction of traction electric motors of an electric locomotive obtained in the MatLab Simulink environment was applied. As a result, it is proved that the implementation of the field reduction systems of traction electric motors using IGBT transistors with the developed control algorithm provides an increase in the power factor of an electric locomotive on average by at least 4%, and also significantly reduces the ripple current of the traction electric motor.

The experience gained in the operation of high-voltage vacuum circuit breakers VBO-25-20/ 630UHL1 indicates an incorrect assessment of the mechanical resource of its individual components and elements. Despite the repeated improvement of the design of the main switch drive, applicable both as part of the new «Ermak» series locomotives starting from number 1000 series, and in earlier numbers, the dynamics of malfunctions continues to persist to the present time. One of the most important elements of the main switch is a latch designed to hold the elements of the drive mechanism in the on position, the failure of the latch entails the failure of the entire section of the locomotive. The article considers three latch upgrades previously proposed by the manufacturer, a kinematic scheme of the drive with a vacuum arc-extinguishing chamber of the switch is developed, the parameters of the preload and trip springs in the drive are calculated, the forces operating during operation are determined. On the example of the latest modernization of the latch using the finite element method in the SolidWorks Simulation software package, a strength calculation was carried out, according to the results of which the stresses arising in its design were determined. As a result of the analysis of the finite element model, the forces critical for the structure are determined, a graph of the dependence of the structural strength margin and the maximum stress in the structure on the acting forces is developed. According to the results of the study, the force at which the most favorable value of the safety factor is provided is determined, for which it is proposed to reduce the critical force by changing the parameters of the compression springs and disconnecting the drive of the arc extinguishing chamber. A loading diagram with the drawing dimensions of two modified springs has been developed.

The article discusses the specifics of the locomotive reliability indicators use in the Russian Railways. Examples of locomotive reliability indicators and the indicators used in the Russian Railways in the conclusion of service contracts, including under the life cycle contract are given. A method of transition from national standard to Russian Railways has been proposed. It is concluded that these procedures can be automated.

It is shown that dynamic systems, «rolling stock - way» due to the unevenness of the path on length should be described by ordinary differential equations with variable coefficients, the method of analyzing differential equations with constant, variable and random coefficients describing the movement of electric locomotive nodes when they move along an uneven path. In the transition to a new paradigm, we can talk about areas of dynamic instability, which in the case of simple parametric resonances develop near critical frequencies, but this is not one specific point, but a zone that expands with increasing coefficients of parametric excitation. In addition, the presence of friction in the system does not guarantee the limitation of resonant amplitudes. The effect of parametric arousal factors on the width of the dynamic instability zone has been established. There are many other features in the behavior of differential equations with variable coefficients, so it is impossible to replace the action of unevenness with some equivalent geometric irregularity, since at this moment there is no exact solution to the problem with which to compare the results of approximate mathematical models.

The article presents the results of studies of the effect of material properties and wheel failures on the process of their machining on the on the car wheel lathe. Developed by complex criterion that takes into account the effect of various factors on the allowable cutting speed. The proposed method for assessing the machinability of cutting wheels through additive criteria. The quantitative characteristics of the machinability of cutting are obtained, taking into account the macroscopic imprecision of the geometric shape, defects in the thermomechanical interaction of the wheel, brake pad and rail, surface defects of the rim, work hardening and the presence of zones of increased hardness. The results can be used in the development of methods to reduce the consumption of carbide cutting tools for machining parts of rolling stock with operational defects.

The article consider the mathematical model for integrated evaluation of the innovation cars operational efficiency in the freight traffic. Created the complex systems of freight rolling stock efficiency indicators of the innovation cars providing aggregate multiplicative effect of increase in productivity. Presents the calculations of the rolling stock productivity indicators model change from operation for one production cycle of innovation cars in the cargo movement. The executed in the article researches and received modeling results show that the rolling stock use efficiency in the cargo movement are consider into account of influence factors from the innovation cars implementation.

A modern solution to the problem of improving the efficiency of the traction rolling stock maintenance and repair processes based on the use of new information technologies is the transition to a locomotives predictive repair promising system. The key element of the predictive repair system in the issue of operational assessment and management of the locomotives technical condition are onboard microprocessor control systems with built-in diagnostic, monitoring and monitoring subsystems. The onboard microprocessor control systems have the ability to carry out continuous or discrete measurement, registration, transmission and accumulation the values of large package analog and discrete locomotive equipment parameters. The functionality of the onboard microprocessor control systems based on information technologies makes them an exceptionally effective means of efficiently organizing maintenance and repair impacts on the locomotive park in order to ensure specified operational reliability and performance indicators.

The article presents the results of research on the efficiency of the electric energy storage system in traction power supply on the example of one of the sections of JSC "Russian Railways". The results of measurements of electric values of electric rolling stock when moving along the railway section under study are considered. Based on simulation modeling, an assessment of the impact of power storage systems on the capacity of the railway section is obtained. Graphs of changes in the minimum travel interval and the minimum voltage on the current collector of an electric moving train depending on the power of the storage system, energy intensity, and threshold voltages for charge and discharge modes are constructed. An algorithm for the operation of the power storage system at a traction substation or linear device has been developed. Based on the simulation results, a graph of the degree of charge is constructed and a series characteristic is determined that allows maintaining the discharge depth at the level of no more than the specified one. Based on the results of calculations, the power, energy intensity and charging characteristics of the storage system are determined, which provide the required voltage level at the current receiver of an electric moving train within the boundaries of interstation zones.

The article presents an analysis of the costs of various fuel and energy resources inJSC “Russian Railways” for the period from 2013 to 2017, results the observations on the reduction of the share of diesel fuel in the total resource consumption structure, the analysis of the distribution of the number of failures of diesel locomotive nodes along the route, the distribution of failures of the cooling system nodes along the route and the distribution of failures of diesel locomotive , the values of power consumed to drive the fan of the refrigerator shaft, various diesel locomotives. Calculated fuel flow ratespent on the drive of the fan of diesel locomotives.

The subject of the article is automated locomotive control functions on the example of electric locomotives in order to assess the current stage of development of the intellectual functionality of on-board control systems. The literature often talks about creating a «smart» or «digital» locomotive. However, it is more correct to talk about the introduction of cybernetic systems with feedback. Such systems were on the locomotive from the very beginning of their appearance and were designed to automate steam control, later to control automatic brakes. These automation systems were mechanical and pneumomechanical. With the advent of electric locomotives, electrical automation systems based on electrical devices, relay circuits are being introduced, which are eventually replaced by diode, transistor control circuits. Later, digital and analog chips were used. The current stage of automation development is associated with on-board microprocessor control systems. The author proposes to divide the intellectual functions of the locomotive into seven directions, for each of which to evaluate their implementation: train driving, drive and brake control, diagnostics, collection of emergency circuits, ensuring train safety, managing the comfort of the locomotive crew. The entropy of the space of intelligent functions is proposed to be estimated according to the modified Shannon formula, where, in addition to the probability of the function being in demand for one trip, the degree of automation of the control process is taken into account. As a result of the analysis, it is shown that the intellectual functions of the locomotive developed already in the 19th century, today the degree of their implementation can be estimated at 60 %, and full implementation can be expected by the middle of the 21st century. The calculation results are summarized in two tables and one dynamic graph. It is concluded that an "intelligent" locomotive is a stage in the evolutionary development of automated locomotive control systems.

The use of twelve-pulse rectifiers instead of six-pulse rectifiers leads to increased efficiency and efficiency of traction substations of the underground. On the basis of experimental research and analysis of circuit solutions, the conclusion is made about the advantage of a twelve-pulse rectifier circuit of a serial type over parallel-type circuits. The use of rectifiers with a parallel type circuit is possible only if there is an equalization reactor, without which technical and economic indicators are reduced. The introduction of the most rational twelve-pulse bridge rectifier schemes of the sequential type can be carried out by upgrading the installed equipment, or by industrial development by manufacturers of dry transformers with different typical power and rectifiers with tablet avalanche valves with coolers based on heat pipes.

The article presents the results of a study of the effect of the functional relationship between the parameters of the microgeometry of the brake disc surface and the level of the stress-strain state of the contact area on the thermal resistance coefficient. The results of an experimental study of the process of changing the step and altitude parameters of the microgeometry of the surface of the brake disc under the influence of normal and tangential forces realized during friction are obtained. It was found that under the influence of normal and tangential forces, the height parameters of the microgeometry tend to increase, and the step parameters tend to decrease. It is shown that when calculating the contact thermal resistance, it is necessary to take into account the functional relationship between the geometric parameters of the microroughness of the brake disc surface and the level of the stress-strain state of the contact area. The calculations performed without taking into account this connection lead to overestimated values of the contact thermal resistance and, accordingly, to errors in determining the values of heat fluxes passing through the contact area of the mating surfaces. The values of the constants, which depend on the design features of the friction unit of the disc brake and are used to determine the nature of the change in the geometric features of microroughnesses, have been specified. The correction of the input parameters of the microgeometry of the surface of the brake disc is performed, taking into account the dynamics of changes in their geometry under the influence of force loading. It is shown that it is advisable to take into account the dynamics of changes in the surface microgeometry in the analytical determination of the contact thermal resistance of a disc brake. The results obtained are recommended to be used in calculating the friction characteristics and assessing the heat fluxes passing through the area of mutual contact of the brake disc and brake pads of the disc brake.

The article describes the study of the mechanical characteristics of polymer insulation, in particular the hardness of the insulating lacquer layer with a different methods of drying it. The influence of the hardness and elasticity of the dried impregnating material on the reliability of the insulating structures during the operation of electrical equipment of the traction rolling stock is analyzed. A device has been created and presented that allows for a simple measurement of the hardness of the varnish film on a pre-selected object of study, which was the insulating finger of the bracket of the brush holder of an electric locomotive traction motor. The process of measuring hardness and results for three groups of insulating fingers are presented: insulating fingers without coating by an impregnating compound (press material); impregnating material, sealed by convective method; impregnating material baked by thermoradiation method. On the basis of the obtained practical results, the effect of the energy supply on the curing process when performing drying by the convective and thermoradiation methods is explained. Also presented are photographs of an electrically insulating lacquer layer from an electron microscope, which allow the microstructure to be evaluated for the presence of gas inclusions, which have a negative effect on both mechanical and electrical indicators of polymeric insulation. A study was made of the relationship between the parameter of electrical and mechanical strength. On the basis of experimental data, the dependence of the breakdown voltage on the hardness of the insulating lacquer layer was constructed.

The article presents a comparative analysis of the effectiveness of automated systems for recording the work parameters of autonomous locomotives. The relevance of the use of such systems is due to the prevention of defects at the stage of identifying possible malfunctions during the operation of locomotives during the inter-repair periods. So the used systems of parametric diagnostics of power plants of autonomous locomotives are considered. Also, for comparison, the experience of foreign research on the use of a diesel locomotive monitoring system is presented. Despite the fact that the existing automated systems for registering the parameters of diesel locomotives have a wide range of functionality that allows you to obtain typical dependences of the power of a diesel generator set (DSU) on temperature and pressure, these systems do not take into account the peculiarities of the flow of in-cylinder processes that can significantly affect the power of the DSU. The article proposes a method for monitoring and adjusting the power of the diesel engine during operation by registering the operating modes of the equipment and determining the actual power of the diesel engine by expanding the range of diagnostic parameters by installing additional sensors for registering measured values for the accuracy of monitoring and tuning the diesel engine and making timely decisions on maintenance and repair of locomotives. A block diagram of the recorder of operating modes with the location of sensors for measuring informative parameters and a diagram of connecting the recorder to the power circuit using the example of a shunting diesel locomotive CHME3 is shown. Software has been developed that can be additionally installed in the standard automated system for registering the parameters of the operation of the CHME3 diesel locomotive with subsequent data processing.

The aim of the work is to study and evaluate the energy efficiency of regenerative braking of an electric locomotive when a freight train is moving at an unsteady and steady speed, to determine the degree of influence on the return of electricity of various factors, first of all, the mass of the train, the speed of movement, resistance to movement, the steepness of the slope of the track profile, driving conditions, the efficiency of traction motors and the needs of an electric locomotive own needs. Also, the purpose of the study is to develop recommendations for improving the energy efficiency of regenerative braking of an electric freight locomotive. Methods used: mathematical analysis, methods of traction calculations and energy balance. The equations of the energy balance of the movement of a freight train and its components in the mode of regenerative braking are considered, which make it possible to identify the main factors affecting the return of electricity at unsteady and steady speed. The calculated dependences of the return of electricity during regenerative braking of an electric locomotive with loaded and empty freight trains consisting of 71 four-axle cars, when moving with reduced speed and constant speed on sections of track with slopes of different steepness, characterizing the influence of individual factors on the return of electricity during regenerative braking of an electric locomotive, are obtained. It is shown that the specific return of electricity during regenerative braking of an electric locomotive with a loaded freight train weighing 7100 tons when moving with a decrease in speed on a track section with a zero profile is approximately the same as with a steady speed of movement on descents with a steepness of 6 ...7 ‰. The specific return of electricity during regenerative braking of an electric locomotive with an empty freight train weighing 1775 tons when moving with a decrease in speed on a track section with a zero profile is approximately the same as with a steady speed on descents with a steepness of 11 ‰ or more. The conditions under which the maximum return of electricity is achieved during regenerative braking of electric freight locomotives are determined. Recommendations have been developed to improve the energy efficiency of regenerative braking of electric freight locomotives.