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

The method of creation of mathematical models of the mechanical oscillatory systems which are turning on in the structure mechanisms with kinematic couples of slippage is offered. It is shown that introduction of mechanisms can be interpreted as introduction to initial model of the additional feedback, in general, to steering on absolute speedup and on an absolute deviation. A basis of the offered technology of creation of mathematical models are representations that in the presence of the mechanism or a mechanical chain of other look power and kinematic indignations form various structures of dynamic interactions. The analytical ratios defining dynamic properties of systems are received. The features of dynamic properties which are shown in various forms of dynamic interactions and frequency characteristics are considered.

This article presents dynamic model for numerical researches of oscillations of the main frame of an electric locomotive taking into account the impact of longitudinal efforts arising in the automatic coupler.

Possibilities of expansion of settle of typical elementary links of mechanical oscillation systems are considered. As examples of links for transformation of movement the screw and level mechanisms are offered. Introduction of new links is equivalent of elementary links with transfer function of differential of second order. The method for definition of parameters of dynamical absorbtions of oscillation are offered.

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.

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.

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.

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 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 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 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.

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 proposes a method for increasing the efficiency of power supply systems for non-tangible consumers due to quadratic accumulation of electric energy on reactive elements in the frequency-beating mode. The proof of the energy efficiency of the beating regime in comparison with the full resonance regime with respect to the implementation of quasiresonance pulsed power supplies is given. The article also deals with the choice of the optimal beat frequency by the criterion of the maximum ratio of the accumulated energy on the reactive elements of the circuit to the one expended from the primary source.

The article presents an analysis of the failures of the mechanical components of the mainline electric locomotives 2ES6 «Sinara» in operation at the landfill of the West Siberian Railway, the causes and consequences of failures of the most vulnerable nodes are determined. The analysis of failures of the mechanical components showed that a significant share of them falls on the components of the wheel-motor unit of the locomotive. The analysis of the design features of the crew part is carried out. The main structural difference of suspension is the absence of leaf springs in the axle box stage, which were widely used on electric locomotives of previous generations. In the body stage, helical springs (Flexicoil) are used instead of the cradle suspension. The connection of the traction motor with the trolley frame is a pendulum. The suspension of the traction motor to the trolley frame is carried out through a leash. When considering the vibrations of railway carriages, it is customary to represent the locomotive and the track as a single mechanical system. The task of forming a mathematical model of the «electric locomotive - path» system is set and a mathematical model of vertical vibrations of an electric locomotive is formed taking into account the dynamics of wheel-motor blocks based on the Lagrange equation of the second kind in the form of a matrix equation, which allows us to assess the loading of mechanical components in operation. The mathematical model represents a system of differential equations in which six equations determine the fluctuations of the bouncing and galloping of the body and trolleys, four - the galloping of wheel-motor blocks, four - the bouncing of wheel pairs together with the reduced mass of the track. The obtained mathematical model makes it possible to determine the level of dynamic loading of the components of the mechanical part of the electric locomotive 2ES6 «Sinara» by integrating the matrix equation using the MathCAD application package.

The article provides a brief theoretical analysis of railway vehicle with nonlinear elastic elements. Considered distinctive features of spring suspension electric locomotives of the old and the new generations. On the basis of differences of a calculation scheme and derived a mathematical model of vertical dynamics of conditional «uniaxial» electric locomotive of new generation allows to estimate the critical speed train crew and indicators of its dynamic qualities.

The work is devoted to experimental study of the roadbed, filled from loess-like sandy, namely, characteristics dynamic vibration impacts arising from the passage of rolling stock, to establish the nature of the damped oscillation, the analytical expressions that can be used to estimate the bearing capacity of the subgrade to the dynamic vibration load.

Analysis of failures bogie side frames of freight cars in the network of JSC «Russian Railways» for the period from 2006 to 2013. Disadvantages of the well-known constructions of trucks of the car of model 18-100. Mathematical modeling of movement of a wheel pair bogie 18-100, set the negative impact of the spread of the values of structural parameters of the chassis of the car on the indicators of its dynamic qualities and driving safety.