Journal of Transsib Railway Studies V.3(43), 2020

The subject of the research is the power thyristor converter of AC electric locomotives and its influence on the power factor of the locomotive. A new method for increasing the power factor of AC electric locomotives with thyristors power converters is proposed and analyzed. These electric locomotives include locomotives of the 2ES5K, VL85, EP1 series, etc. At the initial of the paper, the existing methods of increasing the power factor are briefly considered and their disadvantage in comparison with the proposed method is indicated. The drawback of existing converters is also analyzed, which consists in the presence of a thyristor opening delay at the beginning of the supply voltage half-cycle. The proposed method implies the modernization of the control circuits of the thyristors of the converter, due to which, at the beginning of the half-period, a control current is spontaneously created on the control electrode by means of the supply voltage. As a result, the thyristors open with a minimum delay after the start of the half-cycle. To verification the effectiveness of the proposed solutions, a computer simulation of the operation of the power circuit of an electric locomotive in the ORCAD program was carried out. Simulation was carried out for two options: a power circuit with standard converters and a power circuit with converters upgraded in accordance with the proposed method. During the simulation, the change in the value of the power factor of an electric locomotive was investigated at different currents of traction motors, zone and angle of regulation. Analysis of the oscillograms of converter various arms currents the revealed that when using the modernized converters, the moment of the end of the network switching occurs earlier than in the standard circuit. There is also no area with negative voltage at the output of the converter at the beginning of the half-cycle. At the end of the paper, the values of the electric locomotive power factor are given under various conditions. These results show that the use of the proposed method increases the power factor of an electric locomotive by an average of 1.2 percentage points.

The article presents the results of a study of the effect of the functional relationship between the parameters of the microgeometry of the brake disc surface and the level of the stress-strain state of the contact area on the thermal resistance coefficient. The results of an experimental study of the process of changing the step and altitude parameters of the microgeometry of the surface of the brake disc under the influence of normal and tangential forces realized during friction are obtained. It was found that under the influence of normal and tangential forces, the height parameters of the microgeometry tend to increase, and the step parameters tend to decrease. It is shown that when calculating the contact thermal resistance, it is necessary to take into account the functional relationship between the geometric parameters of the microroughness of the brake disc surface and the level of the stress-strain state of the contact area. The calculations performed without taking into account this connection lead to overestimated values of the contact thermal resistance and, accordingly, to errors in determining the values of heat fluxes passing through the contact area of the mating surfaces. The values of the constants, which depend on the design features of the friction unit of the disc brake and are used to determine the nature of the change in the geometric features of microroughnesses, have been specified. The correction of the input parameters of the microgeometry of the surface of the brake disc is performed, taking into account the dynamics of changes in their geometry under the influence of force loading. It is shown that it is advisable to take into account the dynamics of changes in the surface microgeometry in the analytical determination of the contact thermal resistance of a disc brake. The results obtained are recommended to be used in calculating the friction characteristics and assessing the heat fluxes passing through the area of mutual contact of the brake disc and brake pads of the disc brake.

The article proposes a method of using the mathematical apparatus of the theory of fuzzy sets in automation of the locomotives reliability management, because when writing algorithms there is a problem of transition from not fully formalized concepts of human communication to formalizing software. Examples of the fuzzy sets use in calculating the locomotives reliability are described. When calculating the reliability parameters manually, the volume of calculations does not allow you to move to more complex algorithms. When there are automated systems, it is necessary for each indicator of the transportation process, which affects its reliability, to set the function of belonging to a dangerous and normal value using the mathematical apparatus of the theory of fuzzy sets. Then the risk of a dangerous event will be assessed in probability, taking into account the logical claim to the risk.

The article substantiates the need to update the normative documentation for the selection of smoothing devices for DC traction substations. General requirements for smoothing devices, labor protection and electromagnetic safety requirements are formulated. The main schemes of smoothing devices used at DC traction substations are considered. Recommendations have been developed for the selection of smoothing device schemes for the modernization and construction of new traction substations, taking into account their energy efficiency.

This article touches upon the energy efficiency of train traction at Russian Railways. The relevance of scientific research in this issue has been substantiated. Requirements for organizational and technical measures implemented to improve the energy efficiency of train traction are given. The groups of factors that actually affect energy efficiency indicators have been identified. The creation of an intelligent system for monitoring and planning energy efficiency of train traction is proposed. The goals and objectives of creating such a system are formulated. The main features and classes of intelligent systems in the context of their application for solving the problems indicated in the article are described. The functional diagram of the proposed system and its description are given.

The wheel-motor unit of freight electric locomotives is characterized by the dynamic effect of a wide range of the disturbances due to irregularities in the track. This is one of the main reasons for the high damageability of the gear casings, observed recently, and it indicates the need to improve its design. The proposed design changes for the casing should be directly related to the assessment of the level of the dynamic loading during its operation. The results of the numerical and experimental determination of the natural frequencies of metal casings of traction gear used on electric locomotives of the VL85 and 2 (3) ES5K series are presented. For the numerical determination of the natural frequencies of the enclosures, a modal calculation of the solid model of the enclosure in the Ansys Workbench software environment was performed using the finite element method. A comparative analysis of the distribution of deformation fields in the sidewalls of the casing for a casing that is not fixed to the traction engine and rigidly fixed is carried out. For the experimental evaluation of the natural frequencies of the gear casings, a vibration transducer fixed on the casing was used; the method of excitation of vibrations with a single blow was used to excite vibration. As the result of the experiment, the peak values of vibration acceleration were revealed at some frequencies, which testifies to the emerging resonance phenomena for the casing, and the values of such dynamic parameters for the casing design as natural frequency, Q-factor of the oscillating system, logarithmic damping decrement, relaxation time were obtained. The values of the natural frequencies of the gear housing are obtained by solving a system of Lagrange differential equations of the second kind. The mathematical model of the considered mechanical system created for this purpose takes into account the elastic nature of the casing attachment to the traction motor. The values of the frequencies of the natural vibrations of the gear housing obtained make it possible to evaluate its dynamic loading at the frequencies close to the resonant ones.

In the article it is developed a model for the locomotives life cycle managing in their maintenance and repair using automated technical diagnostic systems. Based on statistical analysis of data on the operation of locomotives, the impact of the reliability of the locomotive and its maintenance and repair system on the efficiency of locomotives is theoretically justified. A method of analyzing the technical diagnostic systems effectiveness using the mathematical apparatus of information theory and of predicting the duration of maintenance and repair time with the dynamic use of accumulated statistics on the duration of previous repairs has been developed.

The article presents the main results of experimental studies within the boundaries of the Fadino - Novoseletsk, Novoseletsk - Strela interstitial zones of the Entrance - Irtysh section. As a result of the research identified problems that currently hinder the online monitoring of operational parameters of the electric rolling stock (EPS) and power supply devices: a lack of data on the work of the traction substations, the presence of EPS without registration motion parameters (RAPS), the lack of process data collection with RAP, the lack of a single source and process for obtaining data, insufficient memory storage device of cartridge, lack of data latch on the locomotive in General, lack a set of fixed parameters, non-constant sampling of parameter fixing, insufficiently detailed final documentation, imperfect software for exporting data from cartridges and lack of binding to global time. Shown the possibility of joining data from different automated systems of JSC "RZD" and measuring systems OSTU, which will allow us to estimate the losses in the traction network, the expense on own needs of electric rolling stock , the electric power consumption for traction and return of electric energy to contact network, as well as move forward with implementation of predictive control operation modes of the electric rolling stock and power infrastructure and Railways in a changing environment in the transportation process, to ensure the best conditions for the realization of tractive effort, regenerative braking, set train schedules, including in case of critical restrictions on the part of the power supply system, preventing train traffic from stopping.

The problem of the assessment of the continuous welded rail track stability at its thermal elongation is considered in this paper. The method for determining the stress-strain state of various elastic objects developed by the specialists of JSC “VNIKTI” is analyzed on the example of a rail of a continuous-welded track section. The essence of the method is to determine the dependence of the natural frequencies of rail vibrations on the applied longitudinal force. As a means of obtaining such a dependence, a modal analysis of a track section model carried out using the finite element method was chosen. The methodology for calculating the natural frequencies of rail vibrations and the description of the created model of the track section and its properties are presented in the paper, the contact interactions of the model elements and boundary conditions are defined in it. Calculations for determining the natural frequencies and modes of rail vibrations are performed, the first four modes of rail vibrations obtained by calculation and experimental methods are shown. The assessment of the adequacy of the created model of the track section is carried out by comparing the natural frequencies and modes of rail vibrations obtained by calculation, by modal analysis methods and experimentally when measuring vibrations on a full-scale object - assembled rails and sleepers, having a similar design compared with the model. It was decided to use the distance between the vibration nodes as a criterion for comparing the obtained modes of natural rail vibrations. The first mode of vibration is selected for further studies. Calculations were carried out and the dependence of the natural frequency of the first vibration mode of the rail on the longitudinal force applied to it was obtained using the created model of the track section. The obtained dependence can be used in the method proposed by the specialists of JSC “VNIKTI” in order to determine longitudinal force, applied to the rails on the full-scale section of the continuous welded rail track.

The globalization of world economic processes poses challenges for the international transport corridors (ITC) development and their sections as part of national transport systems. The tariff policy and regulatory environment of the transportation process form the institutional prerequisites and cargo base of the ITC, which can become a barrier or driver of its development. The purpose of the work is assess the transport corridor development potential and increase the attractiveness of the ITC by using multimodal transportation schemes to attract cargo flows (including export) from related directions. The paper provides an analysis and development of methods for assessing the prospective transport corridor cargo base in the conditions of competition between enterprises of transport modes, taking into account the national transport network configuration. The article presents a method for assessing the cargo base in the conditions of monomodal and multimodal transportation based on logistics principles-reducing the time and cost parameters of the transportation organization scheme. The possibilities of transport modes integrative development are show in the zone of gravity of the transport corridor due to the transport in multimodal transport organization. The geographical Russian Federation «transit» location on the Eurasian continent opens up wide opportunities for the convergence of the European and Asian countries economies through the development of the ITC that runs through our territory. The article considers the prospects for the ITC «North-South» development, which depend on geopolitical and infrastructural (technological) factors. The technological factor relate to such problems of the Russian transport system as the congestion of infrastructure at the approaches to the ports of the Azov-black sea basin, the Moscow-Likhaya-Rostov-on-don-Krasnodar railway, etc., which directly affect the potential of the transport corridor. A graphical diagram present main railway and automobile communications of the ITC «North - South» and road network with distances for tariff calculations.

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.

The national program of socio-economic development of the Far East in the period to 2024 and a term until 2035 [1], approved September 24, 2020, provides for the modernization of the transport infrastructure of the Eastern site of "Russian Railways", in 2021 carrying capacity which should reach 144 million tons and by 2025, capacity will be increased to 182 million tons. In addition, the program provides for the implementation of measures to increase production capacity of the far Eastern seaports and development activities in the Arctic region and the Northern sea route as competitive Intercontinental transport corridor for cargo between the ports of the Asia-Pacific region and the European Union. to ensure the passage of promising volumes of cargo traffic, it is necessary to resolve issues that hinder the effective functioning of the far eastern transport hubs. Currently, the railway infrastructure of transport hubs has a maximum load. In 2018, the unloading of cars that arrived as part of block trains at the port stations of the Far Eastern Railway amounted to 994.46 thousand cars, while loading amounted to 426.88 thousand cars. Such a disparity in the volume of loading and unloading of goods leads to the accumulation of a large number of empty rolling stock at the port stations of the Eastern Polygon of railways, which must be sent for loading at the stations of the western direction. the released rolling stock occupies the tracks of the station and the port, thereby making it difficult to perform shunting work and limiting the station's ability to receive loaded cars. The purpose of this study is to develop proposals for the organization of work with empty car traffic at the eastern railway landfill. This requires to solve the following tasks: to analyze the workloads of the stations and the far Eastern sea ports interaction technology to all the traders in the transportation process, to develop actions on the organization of work of the regional logistics center with the empty wagons, to determine the economic efficiency of the activities. An important areas of work of the regional logistics center of the Far Eastern Railway is to improve the technology of working with the released rolling stock and the organization of a transport and logistics system for the accelerated return of empty gondola cars to the loading station. This paper presents an organizational scheme of interaction between rolling stock operators and management units of Russian Railways to regulate the movement of empty rolling stock. To improve the efficiency of operating the car fleet, it is necessary to organize an operational exchange of information between various owners of rolling stock, the regional logistics center of the Eastern polygon and the unloading station, which should consolidate the car traffic to form a special empty route. the conclusion of the study is to determine the potential economic efficiency of reducing the turnover of block train cars in the direction of «nakhodka-vostochnaya station-loading stations of the east siberian, west siberian and krasnoyarsk railways».

Non-public railway tracks and junction stations of mainline railway transport are the most important links of the «railway - clients» system. At these points, car traffic is generated and extinguished, as well as information and documents are exchanged. When organizing interaction, it is necessary to take into account the interests of not only the carrier and the owner (user) of the non-public track, but also the owners of rolling stock. The most effective solution is to develop an automated interaction management system. The purpose of the work is to determine the factors that lead to idle of cars while waiting for technological operations to be performed with them. This will allow you to find control solutions aimed at eliminating (reducing) the negative impact on the operation of the “railway - clients” system. To achieve this, an algorithm has been developed for the presence of a car on non-public railway tracks, and factors that have a negative impact on the idle of cars on non-public tracks have been identified. The proposed algorithm is the basis for developing a mathematical model for calculating the time spent by a car on non-public tracks. The presence of cars on non-public tracks is presented as a control object for the subsequent development of an automated control system for the interaction of junction stations and non-public tracks. It will have a comprehensive approach to calculating the costs and risks of all participants in the «railway - clients» system.

The article presents the results of the studied soils on physical and thermophysical characteristics in the territory of the city of Omsk. The lack of such data can lead to erroneous calculations in the design of ground probes using low-potential energy of the earth. A method for determining the minimum distance between wells is proposed, which allows to eliminate soil freezing and increase the efficiency of heat transformers.

The paper considers the use of simulation modeling in the reengineering of technological processes for repairing rolling stock units on the example of repairing a bogie model 18-578 of an open-top car. The most time-consuming sub-process of repairing the bolster of this bogie was considered as the object of reengineering. Three options for reengineering of this subprocess were considered, implying a complete replacement of the technological equipment currently in use at repair operations (positions) with more efficient positions of the subprocess. To substantiate the choice of the most preferable reengineering option, the values of such indicators of the functioning of the subprocess under consideration as its productivity per shift (throughput), the load factor of the resources used at the repair positions, the volume of work in progress at the end of the shift, the number of workers employed in production and the costs associated with the possible purchase of new technological equipment. Simulation modeling of the functioning of the considered sub-process of bogie bolster repair was carried out on the basis of the methods of the queuing theory. The construction of simulation models and their assessment of the above indicators were carried out in the Arena RockWell Software environment. When developing simulation models for each of the possible options for reengineering a subprocess, the discipline of its organization and maintenance was taken into account. In the article, for each of the reengineering options, the calculated quantitative estimates of the listed indicators are presented, obtained using the corresponding developed simulation models. The use of these assessments reduces the risks in the development and subsequent implementation of organizational and technical solutions associated with the modernization of the considered technological sub-process of repair of the bolster of a gondola car bogie.

The influence of systematic failures to the functional safety of automated control systems of hazardous technological processes is considered. It is shown that stability ensuring of the process control system to systematic failures is an actual task for today. Approaches to increase the robustness to systematic failures recommended by IEC 61508 are presented. Special attention is paid to methods based on diversion. The functional diversity and technology diversity have been revealed in detail. Examples of using diversification in railway automation systems are given. The main problems of using diversification to increase resistance to systematic failures are formulated. The main advantages of using diversification are increased resistance to systematic failures and reduced risk of dangerous failures through the usage of diversified protection methods at the functional levels of the APCS. The disadvantages of using diversification are a significant increase in the costs of developing and automated process control system maintenance, the difficulty of confirming the different behavior of diversified channels in case of systematic failures, and the lack of an effective method to assessing the sufficiency of the obtained diversification for a given level of safety integrity.