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The article discusses the control systems for mechanical vibrations on the basis of improved modernized nonlinear inverse dynamics algorithms and its use for vibratory stands of technical diagnostics to diagnose mechanical products of railway transport systems.

Transfer of railway lines on the high-speed movement demands strengthening of traction power supply system.Such strengthening can be carried out on the basis of symmetrizing transformers and coaxial cables use.Means of computer modeling of such networks which can be realized on the basis of the methods developed at Irkutsk state transport university are necessary for the solution of practical application of traction networks with the symmetrizing transformers and coaxial cables.Complex technical solution including both from the designated ways of traction power supply strengthening is of interest. Strengthening provides the additional effects consisting in improvement of electric power quality in the feeding high-voltage networks and not traction consumers' power supply,and also in decrease in losses of the electric power and energy efficiency increase. Results of computer modeling of 2х25 kV traction power supply systems with Woodbridge symmetrizing transformers and coaxial cables are given.Modeling was carried out for three options: traditional scheme of 2х25 kV traction network; traction power supply system equipped with the modified Woodbridge transformers; the complex technical solution which is included the symmetrizing transformers and coaxial cables. Modeling results have allowed the following conclusions: application of coaxial cables promotes increase of contact net voltage; due to use of Woodbridge modified transformers it is possible to lower significantly negative sequence asymmetry factor on high voltage buses of traction substations; the greatest effect takes place at complex use of the symmetrizing transformers and coaxial cables.

The cranking of the bandages in service leads to an earlier replacement of the bandage than the pawned resource, which entails both an increase in maintenance costs and a long, simple locomotive for repair. The article shows the main factors that have a significant effect on the strength of the «wheel center - bandage» connection. Particular attention is paid to the mechanical properties of materials. The calculation of the reduction of the contact pressure from the heating of the bandage has been carried out, both for the new and for the worn out. New materials for manufacturing of bandage wheels are considered. It was found that the hardness of the materials can have a significant effect on the strength of the bandage fit to the wheel center. Preliminary calculations of the influence of hardness on the strength of the joint are carried out.The analysis of the influence of the mechanical properties of banding wheel materials on the strength of the joint can be used in the improvement of new materials in the manufacture of bandage wheels and in the development of technology for the formation of wheel sets of locomotives, which in turn will improve the efficiency of wheel sets of lo-comotives.

Development of innovative methods and hardware gives additional opportunities for the solution of various tasks. For example, innovations allow increasing safety in places of crossing highways and railroads by means of detection methods of objects in the required control zone. The big risk of emergencies in places as a railway crossing is caused by a high speed and the inertial movement of the train. In this connection, there is no possibility of timely braking of the train and prevention of collision with an obstacle. At the present time, the biggest percent of accident rate belongs to uncontrollable railway crossings. On such railway crossings completely are absent the blocking means or the warning technical tools. Controlled railway crossings are equipped with the blocking means for the automobiles. Also, they are equipped with the systems of video supervision. But the current systems of video supervision have no function of informing the driver of the train in an emergency. Therefore, to priorities belongs development of technical requirements for a hardware and software system. The automatic analysis of a dynamic situation in borders of a railway crossing, transfer to the driver of the approaching train of the required information belongs to priorities too. This work describes briefly main algorithms of computer vision which allow distinguishing any object on a railway crossing. The example of algorithmic modeling of detection of contours and allocation of a background on video has been considered in this work. Received results led to the conclusion about a necessary adaptation of modern computer vision algorithms for the solution of a detection problem of various objects with the required accuracy and in various working conditions.

This article describes the algorithm for polynomial interpolation analog-to-digital converter with a duration of calibration1 ms. There is an example of reconstruction the missing values for a given accuracy of processing the input signal

According to electric calculations, the overhead system and power lines being the part of the railway power supply are distributed parameters circuits. Wave processes in the overhead system have a negative impact on the power supply lines, laid in the vicinity of the railway, and increase the power losses in the traction power supply system. For the study of wave processes the method of mathematical modeling of non-sinusoidal signals transmission to the uniform two-wire distributed parameters line is provided. The mathematical model is based on the well-known line differential equations (telegraph equations) using Fourier series. The power line is a three-wire line. The paper presents an algorithm to bring the power line equations to the form of two-wire line equations. To assess the correctness of the mathematical model the research was carried out on the physical model of the line. Using the mathematical model there were given the findings of distributed parameters circuits various modes. The proposed method of mathematical modeling of different shape signals transmission to the distributed parameters line adequately reflects the phenomena occurring in the line and can be used for the analysis of electromagnetic processes both in the overhead system and power lines.

The article deals with the organizational features of the Federal law of the Russian Federation on "transportation security compliance requirements to ensure transport security objects (buildings, structures), not related to transport infrastructure objects and located on land adjacent to transport infrastructure objects in the security zones of land transport. Systematized the activities required for the implementation of such transport facilities. In the work used techniques of systems analysis, comparative method, methods of theoretical knowledge (formalisation), obshhelogicheskie methods and techniques of research (analysis, synthesis, classification, the analogy).

The article sets the task of determining the level of dynamic loading in the «trolley-leash-traction motor» subsystem to reduce the dynamic impact in the «locomotive-path» system. The model of vertical vibrations of traction rolling stock, obtained on the basis of the Lagrange equation of the second kind, in the form of a system of fourteen differential equations allows us to estimate the loading of locomotive units in operation, integrated using the MathCAD application package. The approximation of random disturbances using the spectral density of the path irregularity of Professor A. I. Belyaev is chosen as the spectral density of random disturbances. A more detailed design scheme of the crew has been compiled and in order to simplify the calculation within the engineering error, a single-mass discrete model of the path is used. Entering symmetric coordinates allows us to obtain from the original system of differential equations a simplified system with characteristic equations with simple roots, therefore, the natural oscillation frequencies of the bouncing of the body, trolley and wheelset will be determined with minimal error. The transfer function is determined by Kramer's formulas. With the help of a computer, the values are calculated and graphs of the amplitude-frequency characteristics of vertical movements, maximum accelerations of the body, trolley, traction motor and wheelset of the electric locomotive in question are constructed. A comparative analysis of the calculation results and empirical data is carried out. Based on a comparative analysis, it can be argued that the considered mathematical model of vibrations of the electric locomotive 2ES6 «Sinara» is adequate and allows determining the dynamic loading of the locomotive for the entire range of operating speeds. The task of changing the existing design of the suspension system of the traction electric motor of the electric locomotive in question and the mathematical analysis of the vibrations of its nodes in further research is set.

The article discusses the possibility of extending the service life of passenger cars. The analysis of the state of the passenger car fleet has established that the rate of replenishment of reserved cars has been reduced by more than 40 % over the past 10 years, therefore, it is possible to ensure coverage and replenishment of the retirement of rolling stock of this type after the expiration of the standard service life only by extending the service life of existing cars by carrying out capital repairs with the establishment of a new standard service life. When analyzing the power frame of a reserved seat passenger car, it was found that the greatest static and dynamic loads are perceived by its center beam. It is precisely because of the stresses arising in it that an assessment is formed of the further possibility of operating a car both during its life cycle and further use in diagnostics for the possibility of assigning a new service life to it during overhaul repairs. Studies of a number of elements of center beams cut from passenger cars that have expired the standard period have established that the main characteristics of the metal meet the requirements of safety standards, this indicates that the safety margin and resource inherent in them has not been fully depleted. In the study of the presence of residual stresses that have arisen in the elements cut from the ridge beams, depending on the depth of etching carried out according to the method of N. N. Davidenkov in accordance with the TSNIITmash methodology, the most vulnerable and dangerous places of corrosion that require more careful control during the car maintenance and scheduled preventive repairs were identified. In order to reduce the development of residual stresses and the corrosive effect on the load-bearing frame of a second-class car, recommendations and technological operations have been developed for strengthening the ridge beam by the method of shot-blasting with the formation of a uniform fine-pored structure, which ensures uniform application of paint and varnish coating.

The used liquid wash solutions utilization problem in railway depots of Russian Federation was overviewed. Postulated, that it is important to solve ecological and energy efficiency problem together on railways. Authors shows, that in this moment level of development and using resource saving technology in railway depots is too low. Economical, juridical and technological aspect of this problem was analyzed. Shows, that in present conditions we need to treat wash solutions in the closed water recycling process. Simultaneously waste products must be concentrated and then used, taking into consideration, that concentrated waste products contains flammable oil-products. Proposed to combust it and generate heat energy. Taking review of oil-containing waste products concentration and combustion methods. Shows, that heat energy can be used for grows up energy efficiency of railway depots. Described theoretical basics, results of carried experiments, and economic effect was estimated. It`s proved, that proposed technology is useful and can be realized. Preferred construction of washing machines and waste treatment facilities are recommended. Ways of next research work are selected and proved.

The technique of parametrical identification of alternating current railroad traction network is offered. The technique allows receiving trellised equivalent circuits of a traction network which in the presence of measurements’ errors of voltage and currents vectors which aren't exceeding 0,5 % 0,5º give rather high precision of systems modes calculation of traction power supply, providing the correct solution of many practical tasks. Computer modeling showed that uniform traction network mode errors on voltages don't exceed 0,4 % and 0.2º , on currents - 0,9 %, 1.3º.

In article from positions of uniform life cycle locomotives, from creation before write-off, the major factors influencing the level of their reliability are considered. Value of these factors will give the chance to connect mathematical model the potential level of reliability put in the specification on design of new locomotives with the actual reliability in specific conditions of operation and on this basis to determine the optimum parameters systems of maintenance and repair corresponding to maximum efficiency of use locomotives for all life cycle.

In this article a shielding effectiveness calculation method for the radio electronic equipment is considered. Monolayer and multilayer shields made with aluminum, cuprum, steel is investigated. Interaction of pulse magnetic field and conductive shield is simulated using finite difference time domain method. Frequency and time dependencies for the shield impedances are shown. Also pictures of electromagnetic field distribution near shielding are presented. Time dependencies of electric field on the shield external and internal borders are shown.

The goal of the research is to development of a synchronous-replicated model for the assessment of the technical state of a locomotive as a technical system to reduce the occurrence of failures during operation, and as a result, reduce downtime in repairs. When performing the research, the following interdisciplinary and mathematical methods were used: system analysis, computer and mathematical modeling, methods of the theory of artificial neural networks, mathematical analysis. As a result of the research, a mathematical synchronously replicated model for assessing the technical condition of a locomotive based on an artificial multilayer forecasting neural network was obtained. The developed model can be used in monitoring systems, control, diagnosing the technical condition of the locomotive fleet. The original features of the developed model are a low sampling period between polling monitoring tools, versatility, adaptability, efficiency. Based on the developed model, a generalized algorithm for managing the technical condition of the locomotive fleet is built. The proposed model and algorithm solves the ranges of tasks described in the development concept of Russian Railways OJSC related to the implementation of the actual repair system according to the current technical condition of the locomotive, as well as the digitalization of the company’s advanced areas.

The article analyzes the influence of parameters and operating modes of traction power supply system on the value of the useful energy recovery and the amount of electricity losses caused by the energy recovery through the traction power system to various consumers. The amount of energy lost in recuperation determines the degree of efficiency of its use. The approaches to the sequential determination of the recuperation energy efficiency and the calculation of the numerical values of the quantities characterizing the parameters of the traction power supply system, which are necessary for an adequate analysis of the energy distribution flow distribution, are proposed. It is determined that it is sufficient to use the regression analysis method to estimate the influence of the parameters and operating conditions of the traction power system on the energy efficiency of the recovery. The values of the relative resistance of the contact network are calculated depending on the type of the contact suspension, as well as on the traction network supply circuits. It is shown that the parameters and operating modes of traction power supply system affect the losses in the contact network, the losses in rectifier-inverter converters and traction transformers of direct current traction substations, the amount of energy recovery from tires of traction substations, as well as the relative change in losses in the system traction power supply with the use of regenerative braking.

The method of definition of dynamical reactions in mechanical oscillation systems with rigid body with two degrees of freedom is discussed. Understandings about possibilities of creature of structural analogy schemes in relations with systems of automatic feed-back control are used. Transformations of structural schemes for selection of chain of feed-back ties in accordance in examination of object are shown. Such ties represent the dynamical reactions which are looked. Compare analysis with using several approaches are made. Peculiarities of method of definition of dynamical reactions in contacts of rigid body with elastic elements of mechanical oscillation systems are shown.

This article describes the approaches to extract from the video sequence of areas relating to movable objects, which may cause a dangerous situation at a railway crossing. The proposed approach will improve the quality of the mobile object allocation, which will reduce the time image processing to identify moving objects in order to determine the degree of risk. To assess the quality of algorithms was develop a software product and simulated motion capture.

An urgent issue is to increase the power factor of electric rolling stock. One of the ways to increase the power factor in the traction and regenerative braking modes was proposed by the scientists of IrGUPS - this is the use of a rectifier-inverter converter on IGBT with modified control algorithms. This solution allows to significantly reduce the consumption of reactive current from the contact network, increase the capacity of railway sections, increase the technical speed, increase the efficiency of the traction power supply system, and also increase the amount of electricity returned to the contact network in the regenerative braking mode. The study of the performance of this converter is of interest. The transported volumes of goods on the railway lines of the Russian Federation continue to increase. One of the key links in ensuring the specified growth rates of tonne-kilometer work is the availability of powerful traction rolling stock equipped with an appropriate traction drive. A powerful traction drive is characterized by the consumption of significant current. To ensure its flow over the arms of the converter, a parallel connection of power semiconductor devices is used. For modern converters of electric locomotives, 4 parallel branches of power switches are used in the arm. The features of the parallel operation of the arm branches affect the performance of the converter on IGBT transistors. This article proposes to consider one of these features, namely the influence of parasitic inductances on the distribution of currents in the parallel branches of the converter, depending on the connection point of the AC power bus. The study was carried out using the Matlab Simulink software package. The article discusses various options for the topology of connecting power buses and presents diagrams of the distribution of currents in the parallel branches of the arm for each connection method. An assessment was made of such parameters as the spread of the peak current of switching on the branches of the arm, the time of current equalization during the conduction period, and the difference in the magnitude of the current in specific branches. Based on the results of the study, as well as taking into account the existing dimensions for the equipment of AC electric locomotives, a conclusion was made about the most optimal option for connecting power buses.

In the Russian Federation, most railway accidents take place at passive level crossings. The majority of scientific papers on the topic of crossings deal with the improvement of active level crossings operation. At present, there is no effective way to improve safety at passive level crossings. The subject of the study is passive level crossings. The aim of the paper is to develop a set of preventive measures to avoid accidents at passive level crossings. The article describes the cases of traffic accidents at level crossings of the West Siberian railway, studies the scheme of passive level crossings and offers a schematic diagram of the accident prevention system at passive level crossings. The work algorithm of the accident prevention system at passive level crossings and the algorithm of giving the locomotive a notification of an emergency situation at passive level crossings are presented. Using the existing coding scheme of the train protection system as a transmission line for information about an emergency situation at a level crossing allows simplifying significantly the scheme of the developed system. The paper also calculates the maximum permissible time of occupation of the crossing by motor vehicles and the time of coding change in the automatic locomotive signaling system of continuous type. The proposed accident prevention system at passive level crossings does not require additional equipment to organize the communication channel and is cost-neutral. Equipping passive level crossings with this system will improve train safety, reduce the number of accidents and increase the efficiency of the railway transport complex in general.

The article sets forth the procedure for preparation of energy saving programmes for the system of traction electric supply. List of key measures aimed at reduction of losses of electric power in traction network and equipment of traction substations, and also on increase of carrying capacity of railway sections. Presents the results of studies evaluating the potential of energy efficiency of the system of traction electric supply of Railways.

The article describes a method for controlling electrical loads rail consumers using energy storage. Different types of energy storage devices used in rail transport were considered. Performed the optimization problem formulation, selected criteria and the method for its solution. As an optimization method used the method of Hooke-Jeeves. A method is proposed to determine the optimal parameters and the optimal control law of charging and discharging of the energy storage. The criteria and calculation expressions that can be used in the design and feasibility study of the effectiveness of implementation of the stationary energy storage for managing schedules loads rail consumers. The mathematical expression was proposed for the energy storage capacity determination. Two criteria were considered in the optimization problem: a minimum active power losses and minimum reduced costs, and a comparison of results. The form factor used to evaluate the changes in electrical loads. Control of reactive power in the AC mains can realize using semiconductor converters and an energy storage. As a variant the electrochemical cells (lithium-titanate batteries) could be used as energy storage for rail electric consumers. As a result, optimal control of electrical loads allows to get technical and economic effects.

The issue of optimizing the use of lubricants to reduce the in-intensity wear of the wheels of traction rolling stock is considered in the work. The purpose of the work and the test objects are defined. The types of tests, their procedure, short description of tests, and compliance with the technical assignment and technical requirements are presented. Design work was carried out on the development of solid antifriction elements for lubricating the ridges of locomotive wheel pairs (hereinafter referred to as TAEL rods). Bench tests were carried out on a universal friction machine 2168 UMT «Unitrib», which models the contact interaction of the wheel with the rail when applying solid lubricant to the wheel ridge. The linear wear rate of the lubricating element and the friction moment were determined. Explutation tests were carried out on the basis of traction rolling stock of the series VL80, 2TE25KM, ChME3. Such indicators as average intensity of development of cores of TAEL and lubricant cores and average intensity of wear of crests of wheels were defined. The results of laboratory bench-out and operational tests of TAEL rods were obtained in accordance with the order of admission of lubricating materials for wheel-rail contact for use in locomotive combs operated on the railways of the Russian Federation. Operational tests of traction rolling stock were carried out at the landfills of the North Caucasus, South-Eastern and Volga Railways. During the performance test period, the following indicators were monitored: assessment of the impact of TAEL on the wear of co-forest steam ridges, assessment of the actual resource of TAEL production, assessment of the functional capabilities of TAEL rods. According to the test results, the developed TAEL rods received permission to use Russian Railways for the infrastructure. At the same time, the wear rate of the ridges of the wheel pairs of locomotives equipped with TAEL in comparison with the standard rods decreased to 50 %.

The results of field researches of the oscillatory process subgrade erected with sand dunes. The analysis of the oscillations records of particle of sand dunes at the main field, in the frame and be-hind of the subgrade. Given findings change of the value of oscillation amplitudes of dunes sand depending on the speed of trains. Analytical dependence of definition of attenuation of fluctuations in a body of subgrade from sand dunes and behind its limits is revealed.

The article is devoted to the experimental study of the force interaction of the working elements of a disc brake in order to establish the dependence of the coefficient of static friction, taken as a criterion for the potential frictional properties of the friction unit, on the pressing force of the brake linings to the brake disc and the coefficient of mutual overlap. The experiments were performed on a full-scale stand, the basis of which is an electric drive with a power of 75.0 kW and a full-scale disc brake of the LT-10 tram. The stand allows to measure the static friction force under conditions of real forces, pressures, geometry of the contact area, as well as the coefficient of mutual overlap. TR119 and UT22-B were taken as friction materials for brake linings, in the first of which, according to the characteristics declared by the manufacturer, the coefficient of friction decreases with increasing temperature, in the second it increases. During the experiments, these materials worked in a pair of friction with the material steel 35, from which the brake disc is made. The experimental results were processed using the methods of mathematical statistics and presented in graphical form. It is shown that in the range of loads realized during braking, the stress-strain state of the contact area of the working elements of the disc brake according to the criterion of microstrains corresponds to an unsaturated elastic contact. This type of contact is typical for the studied overlap coefficients (0,33; 0,66; 0,98). It was found that with an increase in the pressing force of the brake linings to the brake disc, the static friction coefficient tends to decrease, and with an increase in the overlap coefficient, an increase in the static friction coefficient is observed for all specified values of the pressing force. At the same time, the UT22-V material is characterized by lower values of the coefficient of static friction compared to the TR119 material. Field of application of the results: development and design of advanced designs of disc brakes.

With the advent of new series of locomotives, the development of heavy freight trains, the increasing speeds of passenger trains, the introduction of innovative technical means and technologies, the degree of influence of various indicators on energy consumption is redistributed. The aim of the article is to develop a methodology for monitoring the efficiency of locomotives when changing the set of operational factors. This will make it possible to more accurately determine the estimated change in specific energy consumption, which in turn will increase the objectivity of the assessment of the causes of changes in the energy intensity of transport and will help to reduce energy losses.