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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 heating of the pantograph panhead of an electric rolling stock is caused by the removal of the traction electric current. The increase in temperature is due to the characteristics of the catenary and conductive materials of the suspension and current collector. Current collection low quality also leads to overheating of contact materials and limits the passage of the maximum permissible long-time current when the electric locomotive moves. The uneven distribution of temperature leads to local points of overheating and an inefficient use of the surface of the contact strips. The presented graphs of the density distribution of the position of the contact wire in the plan indicate their dependence on the profile of the path section and the type of the catenary, which determine the heat distribution along the panhead. The proposed methodology of the factor analysis of the effect on the current collector's panhead heating makes it possible to determine the causes of its uneven heating and propose measures to reduce the share of influence of each factors and to provide an increase in the removal of the traction current.

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 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.

In article advanced techniques of laboratory and natural aerodynamic researches of a pantograph and its elements are considered. It is specified that carrying out modeling by means of computational fluid dynamics methods doesn't allow to replace pilot studies completely now. Need of correction of the received results because of influence of change of density of the environment during experimental studies locates. Density of the environment is offered to consider it as an integrated indicator. The main methods of measurement of density of the environment are given, their advantages and shortcomings are listed. The conclusion is drawn that it is most expedient to use ultrasonic measuring instruments to control of an indicator of density. The principle of operation of these measuring instruments is described. The example of use of an advanced technique of laboratory researches of the aerodynamic device for regulation of force of contact pressing of a current collector is given. Researches were conducted for device wing angles of rotation from zero to fifteen degrees with an interval of five degrees. After that aerodynamic characteristics of a wing of the aerodynamic device were under construction and comparison to results of modeling was carried out by means of a computing hydraulic gas dynamics them. The results received in OSTU laboratory well were correlated with results of computational fluid dynamics modeling that testified to adequacy of the applied technique.

The article discusses the criteria used to calculate the probability of failures of devices of the current collection system due to ice and frost deposits on a catenary. The purpose of the work is to determine the influence of climatic and operational factors (including the number of vibrating pantographs, pneumatic drums on electric locomotives within the boundaries of the Directorate for power supply and devices for mechanical cleaning of ice at power supply distances) on the probability of the occurrence of failures of the current collection system and their severity, which will allow to increase the reliability of operation of traction power supply devices in conditions of ice formation and the efficiency of investments by Transenergo and the Traction Directorate for the purchase of these funds. To determine the likelihood of failures of current collection devices due to the formation of ice on the wires of the contact network, it is proposed to divide all factors into climatic and operational. The choice of factors in predicting failures was carried out using a probabilistic Bayesian network based on statistical methods of data processing, as well as correlation and regression analysis. As a result of the research, the factors influencing the likelihood of failures of current collection devices have been determined, and their significance has been assessed using the calculated variances. A method is given for calculating the probability of failure for a conditional distance of power supply, which makes it possible to assess the adequacy of the equipment of Transenergo and Traction Directorates with devices for mechanical cleaning of ice from a contact wire, vibropantographs and pneumatic drums.

The article describes the design of a universal measuring pantograph, designed to obtain during the test trips sets of accurate and adequate information on the quality of current collection due to the possibility of modeling parameters and characteristics of advanced domestic and foreign current collectors, mounted on a modern electric rolling stock. Presented the results of his testing at the West-Siberian railway.

The article deals with the analysis of methods for obtaining statistically reliable data on contact pressure, which are based on the results of inspection trips and data on the design values of the location of the contact wires in the vertical plane andin the path plan. A method for calculating contact pressing with artificial neural networks is proposed. The methods of obtaining statistically reliable data on the contact pressing of current collectors of electric rolling stock without the need for direct measurement, based on the video image of the current collection process and analysis of external factors (weather, operational) accompanying the interaction are considered.

The work is devoted to the consideration of the possibility of using composite materials with an aluminum matrix in the design of electric transport pantographs. Currently, there is a tendency to increase the speeds of electric transport. This fact requires reliable and high-quality current collection, which can be achieved by reducing the mass of the current collector design, including through the use of composite materials. The possibility of using composite materials in parts and assemblies of current collectors operating under conditions of increased current loads and at high speeds of movement and the mechanical characteristics of the traditional ones used in the carriage design and the composite materials proposed for use are analyzed. The design of a carriage of high-speed electric rolling stock has been developed, in which an aluminum matrix composite material was used as a structural material. Statistical modeling using the finite element method in the SOLIDWORKS Simulation software package was performed. Comparison of the strength characteristics of carriage assemblies made of traditional materials and aluminum matrix composite showed the possibility of reducing their weight in the case of composite use without reducing the strength of structural elements. The static characteristic of the carriage in which the composite material was used coincides with the static characteristic of the carriage made of traditional materials, which confirms the possibility of using an aluminum matrix composite without making significant changes to the carriage design. To evaluate the dynamic characteristics of the composite carriage and its effect on the dynamic characteristics of the pantograph, modeling was carried out using the methods of multibody modeling of SOLIDWORKS Motion. The obtained simulation results indicate an improvement in dynamic characteristics when using composite materials, which has a beneficial effect on the reliability and quality of current collection.

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 article examines the technique of designing diagnostic system of infrastructure of electrical railways based on use of bayesian networks for prediction of probabilities of failures. To achieve maximum effectiveness of diagnosis we should minimize the number of input parameters, while maintaining the required accuracy. It is proposed to create a mathematical model of the diagnostic system, that will allow to evaluate the influence of each parameter on the accuracy of prediction of failures. To compensate the lack of source data we can use the advantage of bayesian networks - the opportunity to generate network structure by the method of expert evaluations. Generated bayesian network will perform the failure probability calculation with limited information.