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To increase the speed of the cargo delivery, freight wagons are being developed, intended for the design speed of 140 km/h. One of the important parts of a freight wagon is the bogie, the design of which determines the wagon dynamic behaviour. The bogie of such wagons uses a frame of a rigid design, which is susceptible to antisymmetric loads. The analysis of standards has shown that the strength test during designing a rigid bogie frame under the impact of maximum antisymmetric forces that may occur in operation when a wheel derails is not required, which can lead to a residual antysymmetric deformation of the bogie frame. Theoretical research is performed to estimate the impact of the residual antisymmetric deformation on traffic safety using the wheelset safety factor against derailment. The research results have shown that the bogie frame residual deformation leads to a load redistribution on the wheelset axle journal, which, in terms of the impact on the wheelset safety factor against derailment, is similar to the wagon rolling motion. The wagon rolling motion affects the reduction of the wheelset safety factor against derailment to a greater extent than oscillations during pitching and bouncing. Thus, the permission to operate wagons with the antisymmetric residual deformation of the bogie frame without its non-destructive testing can lead to traffic safety violation. In order to ensure the traffic safety of wagons with bogies having rigid frames and reduce economic losses at the design stage, bogies strength depending on the action of antisymmetric forces should be estimated.

One of the properties of the reliability of the power supply of electric rolling stock of railways is the trouble-free operation of the traction power supply system in various modes of its operation. For post-emergency and forced modes of operation of the traction power supply system, a decrease in load capacity is characteristic. In order to ensure the throughput and carrying capacity of the railway section by traction power supply devices, it is proposed to consider the use of electric power storage devices on electric rolling stock and in the traction power supply system. Studies conducted by domestic and foreign researchers allow us to evaluate the effectiveness of alternative solutions to improve the reliability of power supply, which include various options for the use of electric power storage devices on electric rolling stock and in the traction power supply system. This article presents the results of a review of these solutions, a simulation model of a traction power supply system and an electric rolling stock with power storage devices based on various batteries and a supercapacitor is proposed. Modeling of changes in the modes of operation of the traction power supply system is carried out taking into account the state control of switching devices. The calculation results allow us to estimate the voltage drop at the output of electric power storage devices, including taking into account the exponential zone of the discharge characteristics of batteries, to estimate the voltage change for a given electric traction load depending on the energy intensity of the storage device, made on the basis of the most common types of batteries and a supercapacitor.

The article summarizes and analyzes data on the use of natural gas (methane) as an additive to diesel fuel on the low-pressure line of diesel engines of locomotive CHME3.The results of The gas engine fuel effect assessment on the efficiency of locomotives CHME3 are presented.

Formed research methodology of assessing the impact of pulsed exposure with the one-hundred-Rhone joints of rails on the performance of the dynamic characteristics of the train crew. The dependence of the coefficient of the effect of pulse repetition on the level of energy dissipation in the system and the speed of the crew.

Considered forced oscillations of four-axle vehicle with dual spring suspension. It is obtained that the movement system with six degrees of freedom with sufficient accuracy can be represented by a system with two degrees of freedom. Therefore, the vehicle body has two degrees of freedom: lateral skidding and wobbling, Bouncing and galloping trucks will be neglected. The total number of degrees of freedom of the model equal to two. The method, which leads to a closed solution of the forced oscillation. Defined. That tends and to (n = 1, 2,…), the amplitude of the oscillations will be unlimited. Therefore, the parameters k1, k2 and T must be selected on the basis of required values of amplitudes. As a result of research compiled by the differential equation of motion of the system and obtained analytical solution for the case of external piecewise constant driving force.

The article considers a suitability of mathematical model of stretched rod to determine the relationship of the parameters oscillations of the contact wires and their tension. This model allows you to determine the tension by the frequency oscillations of the contact wire obtained after the passage of the current collector. In this case, the speed of the electric rolling stock will not affect the frequency of the damped oscillations. Thanks to the proposed model, the labor intensity is reduced of determining the tension of wires without interruptions in the movement of trains is reduced and there is an opportunity of operational monitoring of the state of the contact suspension remotely.

This article contains results of experimental studies on the formation of corrosion products as a result of aggressive environment and electric currents action on the reinforced concrete structures. There are discussed a method of creating models with artificial electrocorrosion under conditions close to real working. The results of testing models using the X-ray method and modeling their strength characteristics are presented.

In article the way increases in system effectiveness of cooling locomotives in operation - use relaunches of heat carriers between contours is considered.

The article discusses the approach to generalized evaluation of technical condition of the diesel locomotive power plant functional subsystems based on the reduction of private parameters extracted by results of the analysis graph model to one-dimensional time function with use of mathematical expression of a nonlinear medium. Results of generalized evaluation of technical condition of the power plant fuel system are presents.

In article on the basis of the analysis of design undercarriage locomotives of new generation built the design scheme and formed their mathematical model of the vertical dynamics. Using already known techniques simplify the mathematical models derived a mathematical model of the vertical dynamics of the conditional «uniaxial» locomotive of the new generation and the calculations of the dynamic and traction qualities of the train crew with parameters passenger locomotive EP2K.

A kinematical system of the test bench for experimental investigations of the frequency asynchronous driving gear is consider. Description of the kinematical system and mathematical model on the assumption of back-to-back is produces. As well as example of construction of the mechanical data family on basis of experimental data taking into account of the inner loss in the system is produces. Dynamical model of the asynchronous motor and results of the modeling in matlab simulink is produces.

Currently, in the brake system of operated cars, there is a problem of lack of brake pressure on the wheel, which is necessary for the movement of the train at a set speed in accordance with the regulatory documentation. This is due to the tendency to increase the mass of trains and the maximum load of cars with a constant tare weight, which requires an extended range of pressure control in the brake cylinder by an air distributor or auto mode, depending on the load of the car. To solve this problem, calculations were made of the braking coefficient of cars equipped with air distributors № 483, which showed that the freight car was not equipped with brakes to run as part of a train at a set speed. In the course of engineering studies, it turned out that increasing the spring rate of loaded and medium modes can increase the adjusting range of the air distributor and partially solve the problem of lack of brake pressure. Thus, it is proposed to recalculate the stiffness of the adjusting spring. Calculations of the rigidity of regular and proposed springs were made. The braking coefficient has been recalculated, taking into account the increased spring constant. As a result, this coefficient has increased, which makes it possible to remove speed limits. The proposed method for upgrading the air distributor can be carried out on all types of repairs, which facilitates the implementation process.

The article suggests that the reason for the increased wear of the tires of electric locomotives with an asynchronous traction drive is the increased sliding speed in the contact of the wheels with the rails. It is shown that in thrust modes with high sliding speeds, frictional self-oscillations can develop in the drive. The stability zones of the drive are constructed in the space of its parameters. The model of an asynchronous drive with a «jammed rotor» for the study of skidding modes has been substantiated. It is recommended to install a clutch control system (СCS) on the electric locomotive to reduce wear on wheels and rails. СCS intelligent sensors create an additional feedback channel for the system of optimal traction control - the implementation of maximum traction forces with minimal friction losses. The methods and recommendations presented in the article are applicable to various designs of traction drives.

The article discusses the approach to evaluation of technical condition of the diesel locomotive power plant fuel system as a part of an integrated microprocessor control systems. Presents an approach of generalized evaluation of technical condition of the power plant fuel system. By results of the analysis of a fuel system graph model set of control parameters is selected, the algorithm allowing to establish the reasons of controlled parameters output of admissible limits is developed.

In article stages realization of complex systems non-contact thermal control of the main knots and systems locomotives are considered. The developed techniques of an assessment technical conditions sections refrigerators, electrical machines and the fuel equipment of a high pressure locomotives with use thermovision control method are presented.

In this paper we presented an option accounting compliance joints through mathematical modeling of prefabricated single-walled cylindrical geometric op-totropnyh shells on the basis of the contact boundary value problem of structural type.

A mathematical model describing the dynamics of mechanical oscillatory systems «rolling stock train -railway track» in the vertical longitudinal plane of symmetry. Is equivalent to converting the design scheme. Linearization of nonlinear characteristics in ways. A model of the «generalized» track to assess the existing shock pulses from the joints of rails.

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 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 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.

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.

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.

The article discusses the approach to operational evaluation of technical condition of the diesel locomotive power plant functional subsystems as a part of an integrated microprocessor control systems. Presents an approach to operational evaluation of technical condition of a fuel system. By results of the analysis of a fuel system graph model set of control parameters is selected, the algorithm allowing to establish the reasons of controlled parameters output of admissible limits is developed.

Rational way to improve the operational efficiency of the locomotive is adjustable power.The implementation of this method possible with the use of automatic power regulation implementing the optimal load,the operation mode of the traction and energy unit (TEU) of the locomotive. The aim of this work is to obtain mathematical relationships,establishing the optimal ratio between the number of employees of TD given thrust and speed. Determination of the optimal ratio being in the traction motors is based on finding the minimum power losses at the nodes of the TEU. Search the minimum of complex functions is an optimization problem,which from a mathematical point of view is to determine the minimum of function of several variables with a number of constraints,and relationships. To solve the problem of finding the minimum of a complex function,we used the method of indeterminate Lagrange multipliers. The optimization process is considered at a constant value of the voltage supplied to the TD and sold power.Variables - the force of traction,speed of movement,the ratio of incremental losses,the resistance of the circuit of the armature of TD was assumed constant,which allowed to simplify the solution of the problem,reducing it to find three unknown quantities - current,the number of TD and magnetic flux. The solution to this system of equations for the number TD,participating in the work were obtained analytical dependences the optimum values of the TD depending on the speed,the thrust force on the rim of the driving wheels of the locomotive and tension. Analytical expressions for determining optimal parameters of power regulation of electric DC,allow to obtain the optimal values of the number of workers so and the load depending on the given values of thrust and speed in the entire range of load modes of EPS. The analytical expressions can be used when drawing up regime maps and energy performance certificates EPS,and also in the most important automatic devices of power control of the rolling stock to set the optimal ratio of number of employees and so on.