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Recently, during overhaul of the railway track using modern materials such as geotextiles and penoplex. In turn, they make significant changes to the structure of the ballast, t. To. Are almost insulators. OSTU experimentally it has been ascertained that the contact resistance in the case of using a new type of cloth can be raised to 45 - 150 Om*km. Obviously, this leads to a significant increase in the capacity of the rail relative to a distant ground and can cause injury to personnel operating the traction members network. To determine the capacity of the rail at any point area must take into account the redistribution of power in the elements of the rail network, ie. E. In the rail and the transition resistance «rail - the land». The rail network is characterized by longitudinal rails Zp kilometricheskim resistance, transition resistance «rail - land» rp-s, and the characteristic impedance ZB kilometricheskim spreading factor γ rail network. Analysis of the results lead to the following conclusions: 1) contact resistance «rail-to-earth» has a significant impact on the value of the potentials arising on the elements of reverse current flow circuit; 2) the growth of the resistance «rail-to-earth», associated with seasonal fluctuations in soil resistivity, as well as in recent times, with the capital reconstruction of the roadbed, resulting in a significantly longer (up to several tens of kilometers) area, for which the potential can reach hazardous the value of human life; 3) in the circuit mode on a rail (m. E. When a metal short circuit) almost always rail network will occur potentials exceeding admissible values for several kilometers in both directions from the point of fault, which leads to removal of the dangerous potential at all metal construction connected with the rail and therefore requires a review of the principles of grounding structures.

A mathematical model for diagnosing the state of solid insulation of high-voltage transformers based on an informational assessment of indirect indicators, i.e. entropy, for example, by the content of impurities of various gases dissolved in transformer oil, which allows to determine the technical condition without removing the workload. The values of the average information on the working and faulty state of insulation for various types of gas impurities are calculated.

In connection with the negative effects caused by the fault of the insulators used in an overhead power transmission line of 6 - 10 kV, it is suggested controlling a condition of a post insulator by the device that responses when breakdown current goes through an insulator. The work of the device for identification of insulators defects is described. Equivalent circuits of an alarm device connection with an insulator in an overhead power transmission line are given. The basic processes, that occur in a system of a supporting insulator of an overhead power transmission line in a serviceable condition and if there is a defect in view of geometric capacitance, absorption current, steady leakage current and surface current of breakdown, are considered.

The article is devoted to the issue of power loss measurement in DC traction networks. The purpose of the work is to define the indicators characterizing the degree of determining the energy loss values accuracy when using the method of restoration of the train situation. In the article the analysis of methodical error the value arising at measurement of power losses in a traction DC network is conducted. The occurrence of the error is caused by the indirect measurement method, which is based on the principle of synthesis of instantaneous circuits in real time. The synthesis is based on direct measurements of currents and voltages on the busbars of adjacent feeding and switching points, for example, a traction substation and a sectionalizing station. The data obtained are processed in accordance with the algorithms adopted in the article, as a result of which the coordinates of loads and their current consumption are calculated. In the process of synthesizing instantaneous circuits, it is possible that such a train situation may occur, which will lead to the emergence of a methodical measurement error, due to the peculiarities of the logical and mathematical apparatus of the train situation recovery method. In this paper, has been performed a probabilistic analysis of the possibility of occurrence of methodological error when several traction loads will be present simultaneously on the measuring section, that is, the dependence of the occurrence of the measure of uncertainty on the daily size of train traffic and the dependence of the occurrence of the measure of uncertainty on the minimum inter-train interval. As a result of the study, the proposed method application the limits were established by energy loss measurement the permissible error the criterion. The methodological error the value of the measurement at different variants method of movement on the railroad studied section was assessed

New activities have appeared in Russia as a result of the structural reform of the railway industry. Operation of rolling stock is one of them. Operator companies have assumed this function, but now there is a surplus of rolling stock in the transport market. There is a need to develop methods and algorithms to improve the efficiency of this activity. The aim of this work is to analyze the activities of the owners of rolling stock, their organizational structure, the situation on the transport services market and identify directions for business diversification. Theoretical studies in the field of car fleet management are considered in the work. As a result, the main functions of the operator companies were identified. An assessment of the state of the market indicates that operators are pursuing a client-oriented policy and are gradually expanding the range of services provided. Technological outsourcing as a way of diversification was presented in the final part of the work. It enhances the quality of the operators' services.

For a radical solution of the issue of extending the service life of wheelsets of the freight cars, it is proposed to weld not only serviceable wheels, but also wheels to be pressed against an unacceptable rim thickness. It is shown that in multilayer surfacing, the possibility of obtaining high quality metal becomes more difficult, and heating of a thin rim can have an adverse effect on the gap between the inner surfaces of the wheels. The purpose of the work is to optimize the technological parameters of the multi-electrode surfacing mode, determine the amount of warpage of the wheel disk and study the quality of the deposited metal during operational tests of wheel sets. Experimental surfacing was carried out on the optimal parameters of the multi-electrode process, and a method for measuring the value of wheel warping in conditions of multilayer surfacing was proposed. The results of studies on the influence of the multi-electrode surfacing process on the metal structure and wheel warping are presented. It is shown that under the optimal surfacing mode, favorable conditions are created for obtaining fine-grained structures in the near-seamed zone. Field tests of the freight cars wheel sets were carried out to determine the efficiency and reliability of the method of automatic multi-electrode surfacing of the wheel rim. The task of the tests was a comparative assessment of the resistance of the wheels under study to defects and wear. The implementation of the task involved obtaining data for the wheel sets being researched on the number of cases of wheel failure due to the insufficient quality of the welded surfacing metal. It was found that wheel warping does not cause any dangers that threaten traffic safety, and the weld metal has the necessary resistance to cracking under the action of operational loads.

This article presents the rationale for the need to change the methodology for determining the absolute and relative values of energy losses to train traction. It is shown that when determining the relative value of the losses, it is necessary to take into account the amount of recovery energy returned to the contact network by electric rolling stock meters. To increase the accuracy of determining the absolute value of losses, it is necessary to take into account the energy consumption for the needs of the traction power supply system for prophylactic heating and smelting of ice on the wires of the contact network, as well as to ensure uninterrupted voltage on inactive electrified sections of railways. A formula is proposed for estimating the component of electric power losses in the contact network from the flow of energy recovery taking into account changes in the methodology for determining the loses of electric power for train traction.

The article discusses the process of developing an adaptive model of energy management of the railway enterprise on the basis of production rules. An algorithm for flow control of fuel and energy resources (FER) of the enterprise of the railway industry using mathematical apparatus of fuzzy logic.Proposed to use the base rules of fuzzy conclusions to assess the adequacy of the developed model of management.

In this article, the currently existing methods for determining such a technical parameter as the sliding friction coefficient were considered. The coefficient of friction is one of the main parameters characterizing the operation of tribological pairs of any engineering system. Stable and efficient operation of tribological pairs in such systems, along with high strength and fatigue characteristics, are not only the basis of safety, but also a promising direction in terms of economic benefits in the design and operation of various devices and systems. Accordingly, this area of research is very relevant for the railway industry, and for railway rolling stock in particular. This is caused by a large number of friction pairs in different nodes of passenger and freight cars, locomotives, ensuring safe and uninterrupted movement of rolling stock as a whole on iron drogs. Tribological processes are important both directly during movement and during braking processes. In this matter, the factor of determining and analyzing the sliding friction coefficient comes to the fore. One of these friction pairs is the «pad-wheel» system, which is the executive body of the braking system of a railway train. Optimization of contact in this system is one of the determining factors for the growth of braking efficiency during braking, increasing the working life of the elements of the friction pair, reducing the likelihood of defects. The search for new approaches to the study of friction issues is a direct catalyst for scientific and technological progress in the engineering industry.

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 article outlines modern approaches to determining the maximum permissible continuous current of current collectors when stopping and in motion. The features of techniques that reliably take into account operational factors when conducting tests in laboratory conditions are considered. A mathematical model is given for studying the distribution of current load in emergency mode of breaking a current-carrying shunt.

The structure of a complex of locomotive safety devices (CLSD) is analyzed. A comparison of technical characteristics and design features of ground stationary and transport antennas of the receiving equipment of the global satellite radio navigation system (SRNS) is made. On this basis, the importance of using SRNS in the CLSD structure is shown. It has also been shown that the decrease in locomotive positioning errors associated with the need to increase the signal-to-noise ratio at the input of the receiver can be achieved by the use of active phased array antennas (APARs). APAR are able to form narrowly directional patterns with the commutation of their maximum directions in accordance with the coordinates of the constellation's navigation satellites. Features of the formation of narrowly directional patterns and the possibility of controlling them in a linear and flat uniform APAR are considered. It is shown that the use of APAR in the ground-based equipment of the user is associated with the need: a) changing the approach to designing it for specific applications, - a flat surface of the required size should be provided in the design; b) the modernization of the algorithm for receiving and processing SRNS signals, which must take into account the finite switching time of the radiation patterns, the angle of the mask, the number and coordinate distribution of the navigation satellites in the working constellation.

Now there is no efficient decision to estimate a corrosion condition of an underground part of reinforced concrete support of contact network which is not demanding digging of a support. This problem makes actual a task of development of a hardware and software system of definition of a corrosion condition of an underground part of reinforced concrete support of contact network. As a result of work the software module allowing to realize panoramic shooting of an internal surface of an underground part of a support, to increase quality of the received images, to carry out searching of inhomogeneities and to determine their geometrical parameters, and also to make the analysis of the found inhomogeneities. Implementation of results of work will allow to reduce time and labor costs, and also to increase efficiency of diagnostic works on support of contact network.

Is executed the analysis of the special features of the process of the optimization of the complex systems of video surveillance and video registration in the territorially distributed objects of rail transport. Is proposed the procedure of setting optimization problem during the local level for the group of adjacent clusters into supers-clusters and the step-by-step optimization of entire system at the global level. The procedure of two-level optimization and the association of the adjacent information clusters of system into the supers-cluster make it possible to combine the methods of linear and dynamic programming for the optimization of the complex branched systems on the criterion of minimum expenditures.

The article considers one of the ways of improving the energy efficiency of AC electrical system railways 25 kV, 50 Hz. The proposed approach allows to determine the optimal location and capacity of an unregulated device for compensation reactive power according to the criterion of minimum active power losses in a traction electrical system. Modeling of trains on the site was made using instant schemes. Description of the traction power supply system implemented by the node potential method and Steinmetz’s symbolic method. Optimal value of reactive power for all possible locations of a compensating device was calculated numerically by an optimization method of Hooke-Jeeves according to the criterion of minimum active power losses in the traction network. The mathematical model allows to consider the elements of the traction network, schedules of trains, change of traction loads of electric locomotives, schemes of overhead network. The proposed approach was considered on the example test problem, which solution allowed to determinate the optimal location and required value of reactive power of an technical device. The placement of a compensating device in a certain place will allows to minimize the power loss in the contact network, track circuit and traction transformers from the flow of the reactive component of the current in average for all instant schemes with various traction loads. An unregulated technical device for compensating reactive power which is located between two traction substations reduces energy consumption for traction of trains on the 1 - 2 %.

The analysis of the development of the wheels increased hardness on the example of certain manufacturers, and changing regulatory and technical documentation for production (GOST). A mathematical analysis of the comparison operation wheelsets normal hardness of the wheel pairs of high hardness, based on the receipt of freight wagons from production to unscheduled maintenance. For comparison methods were used: Cramer - Welch and Laplace function. The estimation of av-erage mileage of cars on different types of wheel sets of freight cars and production technology. Developed the basic advantages of high hardness wheelsets.

The article discusses the traction parameters of a new generation electric locomotive. The existing schemes of service areas by electric locomotives and locomotive brigades on the studied railway test site are presented. A comparison is made of the main parameters of DC and single-phase AC electric locomotives, the operation of which is currently organized on sections of movement with trains of calculated mass in the long-term mode of thrust on the climbs of various steepness. The scheme of the proposed organization of operation of a double power locomotive and locomotive crews is presented. Calculated traction parameters of a two-system electric locomotive, taking into account the plan and profile of the track in the proposed areas of operation, specific resistivity to the movement of the locomotive and the composition of the train at the estimated speed, specific accelerating and decelerating forces of the train. When two-system electric locomotives are put into operation, it will be possible to reduce the fleet of locomotives in operation, the number of traction arms due to their lengthening and the number of locomotive change points, reduce the transit time of freight trains, increase technical and local speed, average daily mileage and average daily performance of the locomotive, reduce power consumption per traction . The operation of such electric locomotives contributes to the development of polygon technologies for managing the transportation process, improving the quantitative and qualitative indicators of various railway enterprises.

The article considers one of the ways of improving the energy efficiency of three-phase power supply system of industrial and railway enterprises. Presented and proved a theorem, which allows to determine the necessary conductivity and the reactive branch currents compensating device with asymmetric structure, for which the equivalent conductivity of these elements and the load will be symmetrical and active. In three-phase electric circuit of an alternating sinusoidal current reactive elements allow to redistribute active and reactive power between the phases. The use of a compensating device with asymmetric structure will reduce losses from the occurrence of reactive currents, reverse currents and zero sequence in low-voltage three-phase power system. As an example of the use of the theorem and the calculated expressions for determination of conductance of the branches of the asymmetric compensating devices a special test problem was considered. It shows the values of power losses, the coefficients of voltage unbalance with and without using the device. Considered possible options for the practical implementation of such technical devices.

The article analyzes the current state of electricity measuring on the electric rolling stock. The main shortcomings of the existing electric power measuring systems for train traction are shown. The technical requirements for information-measuring systems of electricity accounting on electric rolling stock are presented. The technology of electricity accounting on the rolling stock with the use of information-measuring complexes and the procedure for processing the measurement results are described. The minimum required list of fixing parameters during the trip is determined. The procedure for calculating the electric power consumption of electric rolling stock within the boundaries of an arbitrary electricity metering zone is given. The prospects of application of the proposed developments on the railway network are considered to provide monitoring of the transportation process energy efficiency.

Research the fatigue crack initiation and the fatigue crack growth in rail with thermomechanical damage. On basis of cyclic test and numerical simulation of rail deflected mode was determine a fatigue failure characteristics and fatigue crack growth characteristic in rail steel.

In article the design of an automatic pneumatic brake of the car with the braking accelerator is offered. Use of the developed accelerator of braking of an automatic pneumatic brake by freight cars allows to reduce a brake way of the train and to reduce longitudinally dynamic forces in the train when braking.

The article deals with measures to improve the energy efficiency of the transportation process. The necessity of creation of an automated system for monitoring the energy efficiency of the electric rolling stock. The algorithm, which allows to determine the reasons for non-locomotive crew specific rules of electricity on the trip. Developed form of protocols, reflecting the information on losses of electricity on the basis of a trip with the time and place of their origin.

The problem of emergency outages of power consumers due to the interruption of the wires of power lines due to ice formation remains relevant for today. As a solution to this problem, an electromechanical class device developed by the authors is proposed in the article. The principles of his work, the features of the design and placement on the wires are outlined. The functionality of the device in automatic mode is described. The substantiation of the maximum efficiency of electromechanical methods of struggle against icing is given in comparison with others, including thermal methods. It is necessary to search for optimal pulse parameters and the design of the actuator.

In article the problem of determination of length of turn of structures, the total loading capacity of the transport which isn't provided with freight, quantity of freight of the transport knot which is in a timepoint in a warehouse on the basis of definition of distribution of a random variable of the freight expecting loading or unloading, and also the free capacity of vehicles taking into account restrictions on the capacity of warehouses is considered. During the solution of a task the following assumptions are accepted: capacity of cargo handling devices of transport knot isn't limited; time of the translation of giving of cars for the pogruzoch-but-unloading front and back isn't considered. The structure is understood as conditional structure which loading capacity is equal to the total loading capacity of some party of real structures, and the moment of its arrival - to the arrival moment on transport knot of the last of them. The received results can be used for determination of optimum values of warehouse capacities and a technological stock of freight of transport knot at the set goods turnover.

In the context of the objectives of and compliance with transportation of corridors for rolling stock and improving the technology of transportation of different modes of transport considered minimization of the geometric factor in positioning navigation, peculiarities of determination of errors of coordinate of the moving objects along physically fixed trajectories on the plane, it is proved the statement about the possibility of recovery of the trajectory of the mobile point on the plane with continuous or discrete measurements of one coordinate.