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This article discusses the improvement of the electrical component of the wear model of the elements of contact pairs of current collector devices under conditions of high-speed movement. The histograms of the electrical wear of contact elements obtained by calculation using the existing and improved mathematical models are presented. Analysis of the obtained histograms allows us to conclude that the calculation accuracy is improved according to an improved mathematical model by taking into account the influence of the aerodynamic effects of the air flow and the speed of the rolling stock.

Considered the features of modern automatic control systems of pantographs. The spectral density analysis of pantograph contact force at high speeds showed requirements for robust control systems, which allows to significantly improve the quality of the current collection. Proposed the ways to improve the automatic control systems for pantographs, aimed at improving the speed and reducing the inertia of the system.

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.

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 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.

The article presents a method of calculation of the thermal state of the pantograph head. The density of the suspension zigzag distribution, taking into account a number of assumptions, has replaced the contact wire position function in the plan. Results of calculating the temperature of the pantograph head at different width of the zigzag of the typical suspension, including zero, are presented. The influence of sinusoidal and tangential contact suspensions on the temperature distribution of the pantograph head is estimated.

The article is devoted to the improvement of the testing method of current collectors of electric rolling stock considering collision efforts from the overhead catenary. The article discusses the features of collision effects on pantographs of electric rolling stock at high speeds. An analysis of the existing methods for testing collision effects on pantographs in laboratory installations and in linear conditions has been carried out. The analysis is carried out and the drawbacks of the percussion pendulum installation for testing current collectors, described in GOST 32204-2013, are identified, and its characteristics are calculated. The design of a shock stand with smaller dimensions and expanded functionality is proposed, and its parameters and characteristics are calculated. When calculating the characteristics of the test bench, mathematical and computer modeling was applied using the MATLAB Simulink environment. The method of bench collision testing using accelerometers and high-speed video camera. It was established that the proposed test bench retains the full functionality of the test facility regulated by GOST, while having smaller dimensions and wider functionality.

In accordance with the long-term development program of JSC Russian Railways until 2025, it is planned to increase the level of economic connectivity of the territory of Russia by expanding the network of high-speed and high-speed transportation. This involves not only the construction of new high-speed highways, but also the modernization of the structures of individual components of rolling stock, as well as the introduction of energy and resource-saving technologies. The use of contact elements with an extended service life is one of the most economical and least costly ways to ensure reliable, economical and environmentally friendly transmission of electricity to rolling stock. An increase in the service life of the current collector element can be achieved, among other things, by reducing wear by the correct selection of contact pair elements, both from the point of view of their tribocompatibility and the ability to ensure high quality current collection. A methodology for conducting experimental studies of contact pairs of current collection devices has been developed and successfully tested at OSTU, which involves bench tests for each pair of contact materials “contact insert - contact wire” in order to determine their optimal combination to reduce wear and increase resource. Estimation of the amount of wear and prediction of the life of the elements of the contact pair is carried out including using mathematical models. However, the use of existing models for predicting wear under conditions of high-speed movement is not accurate enough due to the lack of consideration of the aerodynamic effects and the speed of the rolling stock on current collection processes. This article discusses the improvement of the mechanical component of the wear model of the elements of contact pairs of current collection devices in high-speed conditions. The graphs of the mechanical wear of the contact elements are obtained experimentally and as a result of calculation by a mathematical model. The analysis of the graphs allows us to conclude that it is possible to use an improved mathematical model for modeling the mechanical component of the wear process of the elements of contact pairs with a maximum error value of not more than 5 %.

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.

A mathematical model of thermal processes (dynamic) contact current collector with contact suspension (in motion), which allows to estimate the temperature distribution of heating the current collector during movement. The experimental evaluation of the proposed cooling device performance is given. The thermal model of the current collector in motion mode has been verified.

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 actual process of interaction of pantograph with catenary associated with random processes. The main factors affecting the pantograph are vibrations of the rolling stock, aerodynamic, the instability of the dynamic properties of the pantograph and overhead catenary, etc. In view of the plurality of influencing the current collection of factors theoretically investigate the dynamical system "Pantograph - catenary" in full It is a complex task. A more rational to theoretical studies and sufficient for practical use is to consider deterministic processes. In the numerical simulation of the current collectors are the most common types of the following design schemes (models): lumped mass pantograph model; pantograph multibody schematics; pantograph multibody schematics in CAD-systems, which describe in detail the geometric dimensions and physical properties of each element of the pantograph. In the design of the pantographs is an integral part of the calculation of interaction of pantograph with contact suspension. Contact suspension counted in the calculations in the form of a concentrated mass interacting with the pantograph skid or a spatial system composed of resilient elements of finite length (catenary with distributed parameters). The second type of catenary model is used in the interaction with the first two types of models considered by the current collectors. Based on the features of each of the presented kinds of models, present the technique of the pantograph model selection, depending on the purpose of the simulation.

The article describes the design features of the current collection system of the Moscow monorail and revealed its shortcomings, limiting the possibility of increasing the speed of electric rolling stock. The features of a promising new generation of monorail transport system with increasing speed (up to 150 km / h), the message "city - the airport," which is proposed to use the contact current collection system with flat working surfaces of the current collector and the current lead. The aim of the work was to develop measures and technical solutions for improving the current collectors to provide reliable, cost-effective and environmentally-friendly electric power transmission on board the electric rolling monorail transport systems. The proposed technical solutions have allowed to increase the average life of the contact elements of the current collectors of electric rolling on the active sites of the Moscow monorail from 30 days to 5 months. A preliminary design and manufactured model sample collector rolling device for the new generation of monorail transport system with increased speed. A basic model of the pantograph, which allows to unify all the major components and spare parts for the current collectors of options for different speeds, load current, and other operating conditions and choose the appropriate model, taking into account technical and economic feasibility. The results can be used for the improvement of existing and development of new designs for current collectors of electric rolling monorail transport systems for the high speeds.

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.

Resistive heating of the pantograph head due to the flow of traction current through the conductive elements of the upper node, has an uneven distribution along the frame structure and depends on the location of the contact wire on the insert. The aim of the work is to develop a mathematical model for calculating power losses in the pantograph panhead, allowing to estimate its value, taking into account the zigzag of the contact wire during the movement of electric rolling stock. The subject of the study is the pantograph panhead. The paper gives an example of calculating the frame skid of a pantograph equipped with carbon strips. Experimental studies of the current distribution over the shunts of the panhead depending on the position of the contact wire were carried out in February 2021 in the laboratory "Designs of contact networks, power lines and current collection devices" using a complex for testing current collection devices. The calculation of the heating power of the panhead is determined by the Joule-Lenz law. The results of the calculation showed that the maximum heating power is observed when the contact wire is in the middle of the panhead, while the places of the greatest losses located along its edges are above the places where the shunts are attached. The model makes it possible to obtain a functional dependence of the heating value along the panhead. The obtained results of the skid heating power distribution make it possible to supplement the complex model of the thermal state of the pantograph developed at the Omsk State Transport University with the participation of the authors of the article. The versatility of the developed model makes it possible to investigate various zigzags of the contact wire and evaluate the effect on the distribution of traction current along the panhead, depending on the location of the shunts and their number.