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The article shows the relevance of applying the method of mutual test load of asynchronous traction motors of railway rolling stock. On the basis of the recommendations of existing standards in testing of asynchronous motors is made up of a sequence of acceptance testing of asynchronous traction motors provided in the form of an algorithm. In line with the scheme proposed for testing procedures on the use of the basic equipment of the circuit. The analysis of the main types of tests, the comparison of the classical means for testing the functionality of the inverters eliminated the need for additional DC sources in determining the resistance of the stator windings, additional brake and step-down transformers during short circuit and experience to carry out simultaneous testing of two induction motors increased speed at the stand of mutual load.

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 article proposes an approach to improve the efficiency of using the automatic train guidance system based on instantaneous traction calculations using the actual movement parameters according to current measurements of on-board systems of electric locomotives. A critical analysis of scientific research on the improvement of auto-guidance systems for freight mainline electric locomotives based on modern technologies and machine learning algorithms, neural networks has been carried out. As a rule, all existing approaches to determining the optimal train driving modes are based on the application of traction calculation rules with the empirical setting of movement resistances and other factors without taking into account the real influence of the external environment. The results of comparison of traction calculations in the section of the West Siberian test site according to the current rules and in the KORTES program with the actual data of the on-board measurement systems of the 2ES6 series electric locomotive are presented. Based on the data deciphered from the recorders of motion parameters of electric locomotives of the 2ES6 series, the laws of control of the excitation current at rheostatic and running positions in the traction mode are investigated. The possibility of using the measured data of the on-board systems of electric locomotives to determine the parameters of the train, including the torque of the traction motors, the traction force of the electric locomotive sections, the actual total resistance to movement, inertial properties, etc., is substantiated. The calculation of these parameters for the traction mode is performed. The concept of equivalent mass is introduced and expressions are presented for determining the parameters of a train based on the equation of motion in the form of small increments of measured and calculated data. The obtained results of determining the parameters of the train based on instantaneous traction calculations and data of current measurements of the on-board systems of electric locomotives showed statistical stability and can be used in real time for automatic train guidance systems, providing an increase in the accuracy of determining control actions, taking into account the actual influence of the external environment and increasing the efficiency of using the automatic guidance system for freight trains. locomotives in general.

The article presents the results of the study of the influence of deviations of certain design parameters of bogie from established normative values on a relative offset from the crests of wheel pair in mezhdurelsovom space of railway transport. Such deviations occur in the process of the gradual wear of moving parts in real-world conditions of rolling stock and lead to a change of kinematic parameters of bogie. An analysis of dependence of lateral displacement relative to the wheelset of railway track from the difference between the diameters of the tapered surfaces of wheelset, skating from lack of alignment of wheelsets and difference coefficients rigidity of springs of bogie. The proposed mathematical model allows to not only diagnose technical condition of wagon bogies during their movements on the straight section of railway track, but also forecast the rolling stock maintenance dates the whole on the basis of position measurements of wheel pairs regarding railway track.

As a result of tension increase and significantly loads on the overhead contact lines, there is need to research the tensile stress value for contact and messenger wires. In this paper, the author reviewed the wires operation conditions concerning the thermo-mechanical load. The author has analyzed the results of contact wires low-temperature creep tests. The real rate of contact wires creep is as appropriate as the standard values. At the same time, copper wire elongation is faster than bronze. The author has provided results about contact and messenger wires ultimate tensile stress tests, heated at different temperatures. The ultimate tensile stress rate for the copper and bronze contact wires is reducing by 9 % with temperatures increasing. The ultimate tensile stress rate for the cop-per messenger wires is reducing by 11 %, for the bronze wires - by 4 %, with rising temperatures to 150 °С. Test results have shown that heating of copper wires to temperatures above 90 °С and bronze wires to temperatures above 120 °С leads to a significant immediate reduction of strength. Working conditions for the overhead contact lines wires are close to the critical one. It is not sufficient for reliable and safe operation Author offers to modify regulatory requirements for contact and mes-senger wires concerning permissible heating and also not to divide short-term and long-term heat-ing and only to leave permissible heating.

Cleaning of engine oil from contaminating particles and products of wear of parts is an integral part of reliable operation of friction parts of locomotive diesels. The presence of solid particles in the oil leads to abrasive wear of the parts, and as a result reduces their resourceability. Onboard cleaning systems used on locomotives are not able to carry out fine-dispersed cleaning of engine oil. It is proposed to use an external stationary installation of centrifugal cleaners, which will increase the efficiency of cleaning and clarification of engine oil in the planned types of repair and maintenance of locomotives.

There are results of researching regularities of chafing cylinder-piston group and crank rod mechanism in the diesel engine D49. The results are necessary for creation method of diagnosing locomotive diesel without taking for the pieces but just with the results of spectral analysis of engine oil.

The article develops the topical issue of choosing diagnostic parameters to assess the technical condition of the collector profile of traction electric motors of rolling stock. The results of experimental studies of the collector profile after repair and after carrying out acceptance tests for various traction electric motors of mainline locomotives: TL-2K1 (VL-10), EK810Ch (2ES6), ED133 (2TE116U) are presented. The relationship between the calculated parameters for assessing the reservoir profile using the mathematical apparatus of correlation analysis with a ranking on the Chaddock scale is revealed. A different degree of relationship has been established between the diagnostic parameters that characterize the state of the traction motor collector profile, while most of the known diagnostic parameters have a pronounced correlation with each other. A variety of diagnostic parameters are considered, which can be described by generalized parameters characterizing the reservoir profile. It is concluded that it is possible to use identical diagnostic parameters to assess the surface condition of the traction motor collector at various stages of repair and maintenance. On the basis of the studies carried out, diagnostic parameters have been identified that have diagnostic value and are not related to each other by correlations.

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.

The article describes the case of using the dimensional coordination of the working surfaces of housings of the vehicle-axle boxes of freight cars in the truck mod. 18-100 to determine the design parameters of the technological tools used to perform the machining operation surfaces after coating to ensure wear compensation. The parameters of technological devices grounded. Powered generally constructive solution.

The main subject of this article is consideration of the possibility of applying in electric circuit of the diesel locomotive hybrid power sourse, thats consists of diesel internal combustion engine and traction energy storage (li-ion accumulator battery). The main target of this work is to describe the effectiveness of the applying Li-ion energy storage in traction and diesel internal combusion engine start modes. At the same time, the regular used lead-acit battery is excluded from the locomotive circuit and replaced by a traction accumulator battery. By using numerical simulation methods, the article considers the possibility of starting a diesel internal combustion engine with a traction li-ion accumulator battery and possibility of the increasing the torque of electric traction motors and technical characteristics of the locomotive when the li-ion traction accumutalor battery is turned on as an additional source of energy. The relevance of the results is to get data about increasing carrying mass of the train when using a hybvid energy source on a diesel locomotive. The results of the work demonstrate the effectiveness of the use of a traction battery it traction and engine start modes, while improving the performance of the locomotive. The conclusions of the work contain an analysis of the results of mathematical modeling of the use of a traction battery.

The article assesses the state of the market of transport and cargo services in Uzbekistan, considers the problem of scientific justification of the rational placement of cargo facilities in the country. Analysis of the problems of transport services has shown that freight traffic flows have spread out, negative trends have manifested themselves in the form of regular growth in the cost of fuel and energy resources, tightening of regulatory requirements, growth of customs duties, sanctions in the form of cancellation of previously introduced benefits, and more. However, such indicators of rail freight transportation as the range of container transportation and average travel time are stable in rail traffic, i. e. the diversification of the cargo base and the tendency to full capacity utilization take place. Separately, it should be noted that rail transportation interacts with other transport industries - automobile, air, sea, river and other modes of transport - as partners, not as competitors - multimodal freight transportation is widely developed, special logistics agencies operate to ensure the organization of uninterrupted work during freight transportation. Uzbekistan's railways need to be reformed, and possibly restructured. At least, private capital funds are already being attracted to the system of private carriage operation. The article describes the scientific methods of analysis and synthesis, classification, mathematical statistics used in the study. A roadmap of qualitative transformations for the reorganization of the transport and cargo industry has been proposed, which will bring positive results for the transport infrastructure as a whole.The results of the study will further reveal the capabilities of terminal networks capable of providing in a short time the delivery of large volumes of necessary cargo to domestic and foreign markets, the uninterrupted functioning of the necessary infrastructure for the placement of cargo facilities on the railway network. The object of the study is the state of transport infrastructure with a decisive role in trade.

The article considers the processes of current collection in the system of AC electric traction in high-speed traffic. The existing devices of pantograph and catenary interacting by means of a sliding electrical contact are presented. The comparison of solutions with different horizontal geometry of the contact wire, which affects the speed of the lateral displacement of the contact wire at the catenary supports relative to the axis of the railway track, is given. It is shown that the speed at which the contact point moves along the pantograph strip is also important for assessing the wear of the sliding contact, as is the span length of the catenary supports, the curvature of the track and the speed of the train in the span limits. For the synthesis and analysis of the pair "pantograph strip - contact wire" with a sliding contact, a model for calculating the contact surface is obtained and the energy processes leading to wear of the components of the current collection system are considered. The results of modeling the interaction of the pantograph and the catenary with various variants of the zigzag arrangement of the contact wire are obtained. When implementing a technical solution in areas with high-speed traffic, the preferred method proposed in the article is the arrangement of the contact wire of a chain suspension with a zigzag period increased by two times compared to the traditional one. This solution provides a reduction in the speed of lateral displacement and increases the dynamic stability of the pantograph, reduces the cyclic load on the supporting and supporting structures of the catenary and increases the life of the contacting elements of the current collection system during high-speed traffic.

The article discusses the thermal state of the disc brake elements during braking, taking into account the distribution of heat fluxes between the friction elements. The results of the study of the influence of the thermal resistance of the medium filling the microcontact gaps, caused by reversible deformations of the surface microgeometry, on the thermal state of the disc brake elements are presented. Method - the description of the thermal state of the disc brake elements during braking is made on the basis of the Fourier - Kirchhoff differential equation of thermal conductivity, taking into account the influence of the thermal resistance of the medium filling the microgaps between the surfaces of the brake pad and the brake disc. Results of the work: The calculation of the thermal state of a railway disc brake was carried out taking into account the reversible deformations of the microgeometry of the surfaces of the working elements of the disc brake. The exact dimensions and shape of the disc brake elements are specified in the CAD system (SolidWorks). The graphs of changes in the thermal energy generated and dissipated by the disc brake at different initial speed and duration of braking are given. The obtained dependences illustrate the process of heat energy dissipation into the environment. The inertia of the friction system of the disc brake in relation to the dissipation of the generated thermal energy during braking is shown. It has been shown that the distribution of heat fluxes between the working elements of a disc brake depends on the level of reversible deformations of the microgeometry of the brake disc surface, which directly determine the thermal resistance of the medium filling the microcontact gaps. Taking this circumstance into account makes it possible to increase the reliability of calculations of the generated and dissipated energy by the working elements of the disc brake during braking. The results of the study are recommended for use in calculating the thermal state of the working elements of the disc brake during braking.

This article presents the results of changes calculations in the energy efficiency indicators of the Moscow Central Ring, such as the specific consumption of electricity released for traction by trains of traction substation meters, specific recovery, technical losses of electricity in the traction power supply system when it is transferred to electric rolling stock, including technical recuperation energy loss, depending on various installation options of rectifier-inverter converters in traction substations part.

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.

In the article it is developed a model for the locomotives life cycle managing in their maintenance and repair using automated technical diagnostic systems. Based on statistical analysis of data on the operation of locomotives, the impact of the reliability of the locomotive and its maintenance and repair system on the efficiency of locomotives is theoretically justified. A method of analyzing the technical diagnostic systems effectiveness using the mathematical apparatus of information theory and of predicting the duration of maintenance and repair time with the dynamic use of accumulated statistics on the duration of previous repairs has been developed.

It is offered the technique for the assessment of the efficiency of the application of the mixed hydrocarbonic kinds of fuel in the power installations of diesel locomotives. The model calculations have been executed with a glance of the changing of the physicochemical and thermalphysic characteristics of the fuel mixtures and the service conditions of diesel locomotives.

The analyze of fuel supplying methods in diesels with respect of fuel properties was implemented. The new method was suggested, which can estimate impact of physical and energy fuel properties on power and economic indexes of a diesel. The diesel effective work conditions on low-viscosity fuels are formulated, including regulation and constructive changes in fuel supply system.

The article deals with the question of methodology stop imitation modeling when using modern instruments of mental resources, which are, for example, was Wednesday MatLab. In particular, analysis of factors that determine the duration of the simulation for a given level of accuracy desired results.

The article presents a universal energy-efficient stand for load testing of asynchronous traction motors, and DC motors. It is proposed to use two options of schemes for testing of traction DC motors with serial excitation and asynchronous motors, and traction motors DC parallel (independent) excitation and asynchronous motors, each of which allows you to implement energy-efficient test method - the method of mutual loading. Given the advantages of the use of the proposed stand. The calculation of the main parameters recorded during the test: currents, voltages and power are invited to perform with the help of mathematical models. Each of the mathematical models takes into account the work of the subjects of the asynchronous traction motors and traction motors DC series or parallel (independent) excitation) by the method of mutual loading: electrical and mechanical link. In conclusion, the article sets out the intended results from the implementation of energy-efficient universal stand for load testing of asynchronous traction motors, and DC motors.

The article presents an improved mathematical model of the thermal state of the pantograph head for calculating the temperature distribution when interacting with different catenary with a double contact wire. The model takes into account the unevenness of the pantograph contact pressure on the wires along the suspension span and between them, allows using the databases of the car-laboratory for testing the contact network, calculating the thermal conditions of the skid on various sections of electrified Railways, including transients between them. The paper presents graphs of the zigzag distribution density of the contact wire of the Moscow - Saint Petersburg high-speed line, and defines the transient and steady state thermal states of the pantograph head when the pantograph interacts with them.

A method to an assessment of influence on the expenditure of electrical energy for traction of trains, parameters of graphic time-table in the conditions of using the regenerative braking is being considered in the article. The retrieval of version with the minimal using of energy is based on the modeling of graphic time-table by different train-to-train intervals in the conditions of burst-mode access’ organization on the railway section. By results of modeling it is proposed to represent the derived dependence by changing of electrical energy’s expenditure on parameters of graphic time-table in the form of analytic function of several variables n-order forthe following using by normative plotting of movement for the purpose of curtailing electrical energy’s expenditure for traction on the trains.

The purpose of this article is to create mathematical models for a comprehensive assessment of the quality of repairs of collector-brush assembly drive motor vehicles, including an assessment of mechanical and switching components. The objectives of this study are to determine the linguistic variables based on the generated set of diagnostic features, including "beating of the working surface of the collector", "RMS heights collector lamellae", "amplitude of the first harmonic component of the profile of the collector", "the amplitude of the second harmonic component of the profile of the collector" "RMS heights collector slat excluding the first and second harmonic components", "minimum value of the second derivative of the profile of the collector function", "standard deviation of the second derivative of the profile of the reservoir function," "effective value of the higher harmonic components of the collector profile features" that have the greatest diagnostic value and determination of their membership functions, as well as the definition of the complex index of quality of repair and its components: complex index of quality of machining and integrated commutation quality index in the collector-brush unit of the traction motor. Solution of tasks performed using the mathematical apparatus of fuzzy logic through the use of statistical processing of the results of these pilot studies and the calculation of the diagnostic value of the measured and calculated parameters. As a result of the research formed the mathematical model of quality repair in the space of selected features using the apparatus of fuzzy logic for calculating the value of the proposed integrated indicators for arbitrary values of diagnostic parameters. The results may be used to control the quality of repairs of collector-brush assembly of traction motors of the rolling stock.

A new approach to modeling the operations of railway stations and junctions using Petri nets is proposed. This method enables process analysis both analytically and through simulation, considering the topological features, operational technology of the station, and the structure of the transportation flow. The article provides a detailed examination of key properties of Petri nets, such as boundedness, liveness, and reachability, as well as methods for their analysis. These properties are applied to solve practical tasks, including resource optimization, increasing operational efficiency, and ensuring railway station safety. The proposed model identifies bottlenecks, forecasts potential operational difficulties, and develops measures to improve station performance. Various modifications of Petri nets, including timed, stochastic, and colored nets, are discussed. Each type offers distinct advantages for analyzing the temporal, probabilistic, and structural characteristics and parameters of station topology and transportation flow. The paper presents a model of the throat of a railway station’s reception yard for train passage, including its reachability tree of possible states. Analyzing the reachability tree identifies operational constraints and the sequences of events leading to these states. The model also predicts potential operational difficulties and shortages of maneuvering resources by applying an analytical method based on Petri net matrix analysis. This approach enables large systems, such as complex technical railway stations or junctions, to determine individual critical states that could lead to undesirable events without simulating all possible states.