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The article describes a mathematical model of electro-mechanical devices wear contact pairs current collection of electric transport in conditions as close to real operating conditions. Synthesis of models made in two directions: model the mechanical load and model of electric current flow in sliding contact. The mathematical model also allows to take into account the thermal processes oc-curring in sliding contact by passing an electric current through a sliding contact. Are compared the results of calculations and experimental studies of wear of contact pairs of different materials. Experimental studies were performed on a dedicated test bench installation created in Omsk State Transport University. Relative error between calculation and experiment is not more than 6 %.

The main direction of decrease in operational costs on draft of trains is reduction of expenses by fuel and energy resources, decrease in repair expenses at the expense of increase of indicators of operational reliability of power installations of a diesel rolling stock. It is obvious that the solution of these problems, now when operational profitability of diesels and their reliability are on a limit for the developed service conditions and production of diesel locomotives, it is possible at the expense of application of alternative types of the fuel which use will allow to raise both reliability of a diesel rolling stock, and its profitability under operating conditions. One of such alternative fuels can, is either natural gas, or household oil gas, that is a butane and propane mix in various ratios. In the present article on the basis of mathematical models possible ecological and economic efficiency of use of мix types of fuel on the example of the diesel 2A - 5D49 is shown.

The article discusses the solution of problems related to the development of a simulation model of a DC traction substation designed to evaluate energy and other performance indicators, including electricity quality indicators. The development of a simulation model makes it possible to evaluate the effectiveness of technical measures that can be used at traction substations to solve problems of improving the quality of rectified voltage, reducing non-sinusoidal busbars for their own needs, regulating the voltage on substation tires, and a number of others. Currently, the urgent tasks in the field of non-traction power supply include reducing the non-sinusoidal voltage on the busbars of alarm, centralization and blocking consumers who are sensitive to high voltage harmonics. The simulation was performed for one of the most common circuit solutions, characterized by the fact that a twelve-pulse rectification circuit of a sequential type is used at the substation. The proposed model was developed in the SimInTech software environment and allows you to evaluate the performance of a substation for various circuit states using switches inserted into the circuit. The simulation results are given for a symmetric system of sinusoidal voltages. The simulation results are compared with the results obtained on the basis of an experimental assessment of electricity quality indicators for one of the operating DC traction substations. The above measurement results at a traction substation with twelve-pulse rectifiers of a sequential type were performed synchronously for two pairs of inputs of 0.4 and 10 kV of the traction substation. A comparison of the simulation results shows the adequacy of the developed model and the equipment characteristics used in it, which makes it possible to use it to solve a number of other tasks.

As a result of work statistical data bank of hardware and software complex «Bort» was researched. Methodology for TEM2 locomotive deiesel-generator plant parameters indicating while running hours transformation in integrated time space is suggested.

The state of industrial injuries during operation and repair technology of power supply devices in the power complex of Russian Railways, which confirms the relevance of the development and implementation of methods and technical means of protecting electrical personnel of the power complex of Russian Railways from electrical injury. The analysis of existing methods of maintenance, operation and repair technology of the contact network is carried out. An innovative solution is proposed in the field of electrical safety of personnel of the energy complex of JSC "Russian Railways" through the creation of a single high-precision coordinate space of power supply devices, implemented on the basis of mechanisms for using the global navigation satellite systems GLONASS / GPS.Considered the implementation of power supply and sectioning circuits and main electrical connections in the form of a digital model, which has a mathematical description of the geometric characteristics and spatial position of the contact network; feeding feeders; overhead lines: longitudinal power supply, automatic blocking, centralization and blocking, lines «two wires - rail», lighting; waveguide and other objects of power supply and electrification of railways. On the basis of modeling dangerous situations of electric shock, the electrical personnel of the power complex of JSC «Russian Railways» during the maintenance and repair of overhead contact network devices in all categories of work substantiated the effectiveness of the implementation of a spatial database in the form of a digital model of contact network devices. The use of a digital model of the overhead contact network will increase the level of electrical safety during maintenance and repair of overhead contact network devices and reduce the level of electrical injury to employees of the power complex of Russian Railways.

The article describes the priorities in the sphere tokosеma to improve traffic safety, the development of high-speed and high-speed traffic. To ensure the normal functioning of traffic and rail transport need uninterrupted transmission of electricity. Diagnosis of elements of contact network is one of the important task to prevent power system faults, including those that could lead to an emergency situation. The article deals with the built-in diagnostic system, how they work, an embodiment of their application.

Method of installation places and power choice of reactive power compensation devises in traction power supply system in condition of increase freight miles are introduced in this article. Approaches to definition of reactive power optimal criteria with reactive power compensation installation are denoted. Three criteria for estimation of reactive power compensation installation are offer to review. There is provided method of optimality assessment of this choice.

The article is devoted to the improvement of regression models of the proper resistance of the elements of a grounding device when passing a sinusoidal current through it in order to increase their accuracy. This type of models allows for a fairly high accuracy in assessing changes in physical quantities. The accuracy of the description depends on the number of factors taken into account when constructing the model and the degree of the regression polynomial. The models presented in the article are based on an experiment to measure the proper resistance of the elements of a grounding device, in which a sinusoidal current with the following frequency was passed through cylindrical conductors of four diameters: 10 mm, 16 mm, 22 mm, 28 mm: 25 Hz, 50 Hz, 100 Hz, 200 Hz, 400 Hz, 800 Hz, 1000 Hz. The strength of the passed current varied from 6 to 40 A with a step of 2 A. Due to the large number of factors and the complex nature of the physical processes occurring inside the conductor, a multifactor regression analysis was used. The accuracy of the regression models presented in the article was increased by increasing the degree of the regression polynomial. After constructing the models, their adequacy was assessed and the coefficients of the obtained models were assessed for statistical significance. The adequacy of the models was assessed using the Fisher criterion. As a result of the assessment, it was established that the obtained models are adequate and accurately describe the experimental data. The practical significance of the research is that increasing the accuracy will allow obtaining more reliable information about the value of the intrinsic resistance of the elements of grounding devices, which in turn will simplify further automation of the design and modeling process of grounding devices.

The mathematical model of traction drive Electric locomotive EP20 for research of dynamic processes in a mode of boxing is constructed. The natural frequencies and coefficients of the forms of the dynamic system are determined. The stability of the drive in relation to frictional self-oscillations is estimated. Dynamic loads in the drive elements at a single angular speed of wheel slip are calculated. The recommendations on increasing the dynamic qualities of the traction drive in the sliding mode are formulated.

This article touches upon the energy efficiency of train traction at Russian Railways. The relevance of scientific research in this issue has been substantiated. Requirements for organizational and technical measures implemented to improve the energy efficiency of train traction are given. The groups of factors that actually affect energy efficiency indicators have been identified. The creation of an intelligent system for monitoring and planning energy efficiency of train traction is proposed. The goals and objectives of creating such a system are formulated. The main features and classes of intelligent systems in the context of their application for solving the problems indicated in the article are described. The functional diagram of the proposed system and its description are given.

The aim of the work, the results of which are presented in this article, is to a study of the impact of physical and mechanical properties of rail steel on the parameters of the spectrum emission. The experimental results were obtained by method of atomic emission spectroscopy (AES) in argon. Performed quantitative analysis material of the rail steel and built a multi-dimensional graduations of the description of the spectral lines correlate with changes in the hardness of steel. The results can be used to extend the capabilities of devices atomic-emission spectral analysis

The paper considers a traction power supply system with a voltage of 27,5 kV AC. In the MATLAB-Simulink software environment, a calculation model has been developed that takes into account the parameters of the external power supply system, the train schedule and the current consumption of the electric traction load in the inter-substation zone. It is shown that when choosing the power of the compensating device according to the average value of the reactive power consumed by one train, its passage through the inter-substation zone with direct current causes the same average power losses in the wires of the catenary as in the absence of a compensating device. An increase in the number of trains simultaneously located in the inter-substation zone with the same power of the compensating device entails a decrease in power losses in the wires of the catenary relative to a similar situation without a compensating device, however, the reactive power is only partially compensated. In the calculations of compensating devices, it is proposed to take into account the real existing train schedule, based on the probabilistic assessment of which the average daily reactive power consumed by the electric rolling stock is determined. In this case, it is necessary to take into account the power losses in the catenary. The use of unregulated compensating devices is advisable in areas with a constantly present load. When choosing step devices for transverse capacitive compensation, it is proposed to calculate their power based on a probabilistic analysis of the train traffic schedule and current consumption in the inter-substation zone. When the probability of the appearance of a certain number of trains exceeding 50%, the most effective are compensating devices, the power of which is selected on the basis of the average power consumption of all trains without taking into account the time of no load in the inter-substation zone, as well as two-stage devices, the power of the first stage of which is selected according to the current consumption of the two most likely occurrences of the number of trains.

The article deals with the suitability of wave response method aptitude for traction engines turn-to-turn armature coil insulation testing and development of testing coil adequate model for further researching of physical processes occurring while testing. The method of wave response readout in armature coil reported is described in the article. The equivalent circuit of armature coil relating to wave response method is given. The wave responses got during physical model testing, simulating in MATLAB are shown. The real and simulating results analysis allows you to approve the proposed equivalent circuit adequacy. This equivalent circuit may be used for simulating of traction engines insulation fails relating to wave response method.

The expediency of introducing dynamic models of defect development into the practice of vibration diagnostics of rotor mechanical units is substantiated. It is shown that as a basis for the creation of models it is advisable to use empirical data. An example of a dynamic model of a small gear defect of a wheel-gear unit is given. The approximate amount of work on the creation of dynamic models is determined. Methods of realization of dynamic models of defects "in the big" are offered.

In the modern operating conditions of railway refrigerated transport, the primary tasks have become increasing the energy efficiency of rolling stock and reducing operating costs. This article presents an analysis of the energy and economic efficiency of replacing the power equipment of an autonomous refrigerated car to transition from diesel fuel to liquefied natural gas. To perform the analysis, the authors developed an engineering model of the energy balance for the autonomous refrigerated car equipment, supplemented by a cold recovery loop from liquefied natural gas regasification. The research methodology is based on a systems approach that considers the thermodynamic properties of the proposed replacement fuel and the specifics of heat exchange processes in the cargo compartment. Based on the obtained model, a comparative analysis was performed between the calculated indicators of the considered power equipment designed for liquefied natural gas and the operational data of existing diesel analogs. During the evaluation of the fuel replacement effect, the technical feasibility of ensuring standard car autonomy indicators when transitioning to liquefied natural gas without deteriorating the rolling stock's operational characteristics was confirmed. It was established that cold recovery from liquefied natural gas regasification significantly improves the equipment's energy performance, ensuring a sufficient level of energy autonomy and reduced fuel consumption through the beneficial use of the gas's physical exergy. The developed model allows for a comprehensive assessment of the systemic effect of replacing diesel fuel with liquefied natural gas, taking into account various temperature regimes of the car body. The conclusions demonstrate that converting refrigerated rolling stock from diesel fuel to liquefied natural gas for use as both energy fuel and refrigerant (cogeneration) is expedient.

The drawbacks of the step-by-step automatic voltage control system under load AVC and the non-contact automatic voltage control system NAVC with the reactor switching device of the converter transformer used in the traction power supply are analyzed. The scheme of a thyristor-reactor switching device (TRSD) connected to the primary winding of the transformer is considered. A brief description of the operation of a transformer with TRSD and the procedure for calculating the symmetrical and asymmetrical external natural characteristics of a converter unit with TRSD are given. Based on the dependence of the energy indicators of the converter unit on the resistance of the uncontrolled reactor TRSD, a method is proposed for calculating the rational resistance of an uncontrolled reactor, where the power factor of the converter unit is taken as the criterion of rationality. The method includes two stages: the first is the calculation of the values of the power factor of the converter unit depending on the resistance of the uncontrolled reactor and the load current of the converter unit; the second is the determination of the average load current value of the power factor of the converter unit for each considered value of the resistance of the uncontrolled TRSD reactor and the determination of the rational for the considered external natural characteristics of the unit. In accordance with the presented methodology, the calculation of the minimum permissible and rational resistances of the uncontrolled reactor TRSD as part of a converter unit with a converter transformer TRDP-16000/10 was made. Taking into account the selected rational value of the resistance of the uncontrolled reactor TRSD, a calculation was made and the external natural characteristics of a converter unit with a TRSD and a converter transformer TRDP-16000/10 are presented. The performance check of the presented calculation method for solving the problem of choosing the rational resistance of an uncontrolled reactor was carried out on a physical model of a converter unit with a TRSD, with a 12-pulse rectifier unit, with a 30 kVA transformer and a linear primary voltage of 380 V. Comparison of experimental and calculated values showed a slight discrepancy, the permissible error was not exceeded. Determination of the resistance value of an uncontrolled reactor based on the developed methodology provides the highest values of the power factor of the converter unit.

The analysis of the influence of operating modes and the development of the residual life, expressed through thermal wear of the insulation of the asynchronous traction motor. The research subject is to obtain new patterns of change in the residual life of the stator winding insulation, which make it possible to determine the specific life of the winding for each mode of the asynchronous traction motor. The research aim is to create a system for determining and assessing the residual life by developing methods and technical means of monitoring and comprehensive diagnostics, as well as theoretical justification using the method for determining additional thermal wear of the stator winding insulation, taking into account the combined effect of the starting transient process, the long-term allowable load schedule and the maximum allowable temperature values. To determine and assess the possible residual life, the method of sequential influence of starting transients, maximum permissible load curves, as well as long-term overloads at the maximum permissible temperature, taking place under various operating factors during the movement of electric rolling stock, was used. The expediency of determining the function of uneven resource development, which has a monotonic character and is approximated by a linear double exponential and exponential functions, is shown. Specific proportionality coefficients are experimentally determined, which characterize the decrease in the dielectric strength of the insulation with sequential alternation of maximum and long-term permissible loads and maximum permissible temperature values, followed by obtaining an analytical relationship that predetermines the insulation resource. It is shown that the determination and assessment of the residual resource under typical modes practically makes it possible to clarify the timing of preventive measures and predict the expected duration of accident-free operation and forestall the premature failure of the asynchronous traction motor.

Flow ranges are given in article by an air stream of the aerodynamic device of a current collector the AIST, received by calculation, using which aerodynamic characteristics of this device are defined. Experimental aerodynamic characteristics of a current collector the AIST of heavy and easy type with use of the aerodynamic device are provided.

The results of the study the possibility of using artificial neural networks in identification problems failure status diesel D49, the results of spectral analysis of the crankcase oil. The obtained results are needed to develop software for evaluation of the degree of wear and tear as a result of the diesel locomotive spectral analysis of engine oil.

The article analyzes the change in the strength properties of structural materials used in the production of current collectors of electric rolling stock, proposes a method for calculating the reduction of resource indicators of elements of a system of moving frames of electric current collectors made of hardened aluminum alloys as a result of the thermal effect of the flowing current. The features of heating the levers of the current collector during laboratory tests are considered. The most heat-stressed units and elements bearing a mechanical load are installed. The dependence of the thermal degradation of the levers of a system of moving frames at various temperatures is determined. The nonlinear conversion function is calculated for calculating the integral value of thermal wear. A method is proposed to increase the reliability and performance of current collectors, based on the use of permanent temperature control of its key elements.

Principal directions for increase of locomotive operating efficiency are determined in the article based on statistical estimates as per data on the main domestic locomotive series. Work ratio is suggested as universal indicator. It is demonstrated that in addition to locomotives' reliability enhancement, increase of the trains' haulage management system efficiency is also a large reserve. It is proven that the number of locomotive units can be reduced at least by 2,000 thous. units.

The design of the hydrostatic fan drive of the cooling system of diesel engines of passenger locomotives of the TEP70 all series is considered. According to the results of the analysis of malfunctions of components and parts of the cooling system of locomotives, it showed that the main reasons for the failure of the hydrostatic fan drive are: the destruction of the housing and overheating of the bearings of the hydraulic motor, oil leakage at the installation site of the rubber diaphragm and loss of rigidity of the spring of the thermostat. The reasons for which are often the temperature conditions and the life of the parts. The article discusses the issues of improving the efficiency of the hydrostatic fan drive of the cooling system of diesel locomotives. An increase in the life of the hydraulic motor can be achieved by eliminating idle from its operating time, since it is connected by a rigid coupling with the diesel shafts. Ensuring the independence of the operation of the hydraulic motor relative to the diesel engine is possible by changing the design of the hydraulic fan drive, by installing a viscous coupling for the transfer torque of the shaft only during the period of necessary useful work, when a certain oil temperature is reached. To increase the reliability of the thermostat, the possibility of installing an additional rubber diaphragm with increased tension force, for trouble-free operation of the thermostat when the pressure reaches 12 MPa and when the oil viscosity decreases, is considered. A malfunction of the thermostat often leads to the most serious consequences, up to the failure of the locomotive, where the most common cause is the loss of rigidity of the spring of the thermostat due to the jamming of the spool, which affects the redirection of the oil flow, and there is a high probability of an increase in the temperature of oil or water in the system. The considered main malfunctions of the hydraulic fan drive and ways to solve them will significantly increase the reliability of its operation and the efficiency of passenger locomotives.

The article describes the main provisions of the optimized system of the electric locomotives maintenance service and repair, as well as the results of the experiment to increase between-repairs run of the electric locomotives in the Eastern polygon. The author examines the impact of techno-logical preparation of production on the quality of repair and the number of failures in the transi-tion to a more streamlined system. The article proposes a method of calculation of adjustment and development cost of technological documentation, which is an integral part of technological prepa-ration of production. The cost calculation includes qualifications and salaries of industrial engi-neers, the complexity and volume of developed or adjusted technological documentation. The author gives the example of calculation of adjustment and development cost of technological docu-mentation in depot conditions. The economic effect from the implementation of this methodology and optimized system repair shows its effectiveness and viability. Due to the adjustments of techno-logical processes of the electric locomotives repair, the number of failures during operation, dis-covered during the experiment in the Eastern polygon, will decrease. Benefit from the increased between-repairs run and reducing the complexity of some of the repairs will cover the costs of im-plementation of the optimized system.

The subject of the research is a sub-rail foundation containing a viscous element. The purpose of the study is to evaluate the effect of including a viscous element in the elastic system (rails, sleepers, ballast, etc.) on the overall rigidity of a railway track. The design of a sub-rail foundation with a viscous element is described by the generalized Maxwell model and contains a shell filled with a Newtonian fluid, in particular air. Pneumatic shells with different thicknesses were considered. The modeling was carried out in the finite element analysis environment. Mathematical models of a track section with a sub-rail device containing a pneumatic shell were constructed. The calculation results showed the absence of a sharp increase in internal force factors and stress concentration in typical track sections when laying a sub-rail foundation with a pneumatic element. A change in the overall rigidity in the vertical plane did not lead to a significant change in bending stresses in the edges of the rails. With a small shell thickness, the bending stresses in the upper area of the sleeper decrease to 35 %, and in the lower area by 15 %. The maximum increase of up to 8 % is observed with a sharp difference in the shell thicknesses. Compressive stresses on the sleeper in the under-rail zone increase with a small shell thickness of the device due to the redistribution of forces to a smaller number of under-rail supports when the overall rigidity of the structure changes. Increasing the shell thickness to 40 cm leads to an increase in mechanical stresses of up to 20 %, which is an acceptable value with a large margin. The use of under-rail foundations with a viscous element is recommended for temporary railway tracks when laying them instead of ballast and sleepers, which allows for the track to be quickly laid and also quickly dismantled.