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The article presents a criterion for choosing the optimal type of wavelet function for digital processing of current and voltage values in the analysis of the electric network mode. The increase in the share of electric receivers that distort the quality of electricity sets the task for researchers to use more advanced mathematical tools for analyzing and modeling such power supply systems. The discrete wavelet transform allows the harmonic analysis of currents and voltages under non-stationary non-sinusoidal modes. One of the key tasks in the development of digital technologies in the electric power industry is the creation and development of intelligent electric networks with the introduction of new algorithms for digital data processing and decision making. In this case, algorithms for compression and remote recovery of data on the consumption and production of electrical energy in the cloud should be developed. The wavelet transform eliminates the negative spreading effect characteristic of the Fourier transform in the analysis of non-sinusoidal non-stationary modes. Based on the Parseval equality, the wavelet transform makes it possible to determine the spectrum energy of individual frequency ranges determined by the depth of decomposition and the sampling frequency of the signal under study. The calculation of the energy of the spectrum of wavelet coefficients allows the compression of the flow volume of instantaneous values of voltages and currents. The article presents the results of continuous and discrete wavelet current conversion when switching a battery of static capacitors. Information compression ratio exceeded 5.3. The wavelet transform was performed using eight different wavelet functions. The criterion for choosing the optimal mother wavelet determines the condition of the maximum energy of the spectrum and the minimum standard deviation when restoring the original signal.

In article process of expeditious calculation of capacity and intertrain intervals is considered within the concept of coordinate management of train service. The technique directed to the solution of problems of search of reliable intertrain intervals in real time, calculation of the postemergency set operation and estimation of reliability of traction power supply system, based on use of the device of artificial neural networks and modern means of interval regulation of the movement of railway transport is offered.

The article discusses the assessment of the impact of train schedule on the amount of electricity consumption for traction on sections of DC I-th profile type way. The proposed parameters of the train schedule, influencing the electricity consumption for traction on sections of DC I-th profile type way. The major scheduling options included statistical quantities and parameters characterizing the conditions of the batch passing trains, stop and solid thread schedules for truck-driving. Based on simulation modeling provided the main based on changes in the volume of electric energy for traction on the plot of the traction electric supply system when changing the parameters of the timetable. The dependences of the volume change of electrical energy for traction allow you to evaluate and determine the ranges of the parameters of the graph in which the variation of volume is minimal. in the considered ranges of the parameters of the train schedule, the amount of electricity for the areas of DC with the I-th profile type varies within 1 % with the constancy of other factors..

The article considers the issue of providing protection for the contact network when removing 3.3 kV traction substations from the Nazivoye direction of the Omsk power supply distance of the West Siberian Railway. When the 3.3 kV switchgear is brought out to repair, the protection zone for connection of the contact network of adjacent traction power supply system objects (traction substations, sectionalizing stations, parallel connection points) increases. To ensure the protection of the DC contact network, lowered settings for the operation of high-speed circuit breakers are introduced, which inevitably limit the capacity of the section for the passage of freight trains. Considered the existing order of withdrawal of equipment for repair with the inclusion of a traction substation post section. The limitations of skipping freight trains during the implementation of the existing scheme are estimated. Short circuit currents are also calculated and the settings for the protection of high-speed circuit breakers are selected when the sectioning station is switched off and the sectional disconnectors of the station are switched on. It was found that the condition for selecting the protection settings is not fulfilled when detaching from the minimum value of the short-circuit current. To reduce the limitations, a prototype of a short-circuit contactor of a direct current 3.3 kV grid has been developed. The use of a short-circuit-breaker allowed the protection of the contact network, for the time of the withdrawal of the switchgear equipment for repair, without transferring to lower settings for the operation of circuit breakers. Also in the article are given the technical characteristics and features of the proposed device design. The results of a test of a short-circuit of a 3.3 kV direct current contact network in the Dragunskaya-Novokievskaya-Lubinskaya section are presented. The main directions for further work are determined.

The article contains the main provisions of the methodology for determining the indicators of electric locomotives energy efficiency. The results of indicators calculations for electric locomotives of series 3ES5K, EP2K and 2ES6 are presented with reference to the current sections of railways. The proposed approach can be used to establish the level of energy efficiency of various series of electric rolling stock and their objective comparison when operating at different sites with trains of various masses with the aim of further creating an automated system for optimizing the use of traction resources of JSCo Russian Railways.

Some aspects of soil testing are discussed this article to determine the stamp bearing capacity of piles. The techniques of plating tests has been proposed with anchoring of the shell or casing piles future. This method allows you to evaluate the resistance of piles on its end and side surfaces.

The operational reliability of the electrification and power supply system and the associated traffic safety is mainly determined by the technical condition of the contact network-an element that is extremely difficult to reserve in any way. The state of the contact network devices of the East Siberian railway is indirectly characterized by periods of electrification of sections. The equipment of the contact network, put into operation in the 1960s and 1970s, has developed its design life, does not have the required load capacity enough and reduces the reliability of the electrified section. The article shows that the purpose of improving the reliability of electrical equipment in the operation of power supply devices is to predict the state of its elements, in particular the metal supports of the contact network, as an object of study. Correctly assess the state and resource of the contact network devices will allow the use of the latest diagnostic systems by personnel in practice, using mathematical apparatus and modeling methods. It is shown that by monitoring various parameters characterizing the support, it is possible to detect a change in the technical condition of the object of study in time and to carry out maintenance in the period of time when there are deviations of parameters beyond unacceptable limits. The statistical data on the state of the support economy at the VSZHD are summarized, the main types of damage to metal support and supporting structures are given. It is shown that new types of damage to metal structures, not classified earlier, are revealed, that qualitative and quantitative assessment of the state of metal supports of the contact network, which have various structural damage is possible using methods, modeling, simulation and evaluation of the state of structures. FEMAP, an independent computer-aided design system from Siemens PLM, is used as an independent full-featured environment for modeling, simulation and evaluation of the results of the analysis of the characteristics of metal supports of the M6/10 model

The traffic speed increasing on the railways makes strict requirements to the supporting and supporting structures of the contact network, as well as to the parameters and indicators of the contact suspension. The presence of dry friction in the cantilever attachment points indicates a negative effect on the accuracy of adjusting the wires of the contact suspension and on its parameters. The article presents the results of studies of the dry friction value in the console fastening points depending on the type of the contact suspension and suggests a method for reducing friction in the console attachment points. The results of calculations of the effect of friction in the console attachment points on the tension variation along the length of the anchor section are presented.

The possibility of fatigue crack propagation in the region of compression stresses is considered. After each semi-cycle of cyclic loading the stress-strain distribution near the tip of the crack is determined by the finite element method. It is shown that maximum of the tension stresses increases in the region of compression. The obtained results allow to present the possible ways of the above-mentioned fatigue crack propagation.

The mathematical method of calculation of currents of corrosion of two models of grounding models - ekvipotentsialny and nonkvipotentsialny is presented. Soil and electric corrosion of both models is considered. The mathematical method of calculation of sizes of corrosion currents and potentials will allow to estimate a corrosion condition of elements of grounding system of traction substation.

On an inside factory industrial transport different transporting machines (railway faucets, motovozy, electric locomotives and other), moving on a claotype way, are used. For realization of the required manipulation loads the transporting machines indicated higher must be stopped at one or another points (positions) of claotype way with high enough exactness, that is provided with a help. The analysis of existent control system rotined that they provided exactness of keeping of transporting machines not always. For the increase of exactness of the system of the automated keeping, oriented to application on an inside factory claotype railway transport technical solution, protected patent of Russian Federation.

The article deals with the issue of the formation of defects of thermomechanical origin (sliders) on the rolling surface of wagon wheels during their skidding along the rail, since such defects affect traffic safety to a greater extent. In addition, such defects on the tread surface of the wheel are difficult to eliminate in the repair industry. It is known that the slider is formed when the wheel is jammed and its translational movement (sliding) along the rail, the so-called skid. As a result, in the area of contact between the wheel and the rail, intensive wear of the wheel material is observed, as a softer element, and a wear area (slider) is formed. The slider is evaluated by such a parameter as the depth relative to the wheel tread. An algorithm for calculating the depth of the slider is given under the condition of a short-term movement of the wheel along the rail skidding. The initial data were determined and a calculation was made with the construction of graphs that reflect the dependence of the slider depth on the speed of the rolling stock and the load on the axle of the wheelset during short-term skidding. A technique for calculating the maximum temperatures in a pair of sliding friction "wheel-rail" is described. The values of the maximum temperatures in the contact patch are calculated when the wheel moves along the rail skidding. Based on the results of the calculations, graphs of changes in the maximum temperatures on the wheel tread surface in the area of friction on the rail under various operating conditions were plotted. An assessment is made of the possibility of indirect determination of the depth of the hardened metal layer in the area of the slider, depending on its dimensions, measured when the wheelset was received for repair.

The article outlines the principles of quantitative evaluation of information security from the viewpoint of the theory of games. Definitions of the game matrix and its quantitative interpretation. Offered practically implemented method of analysis, planning and design of information security based on the proposed models.

The results of the study the strength characteristics of loess loam under triaxial when exposed vibrodynamic load of high-speed trains. Research carried out on triaxial vibration, based on the principle of operation of the plant simulation vibrodynamic exposure to periodic changes in hydrostatic pressure in the working chamber triaxial. The experimental values of specific cohesion and angle of internal friction, and the values of their relative decline under the influence of vibrodynamic load.

This article discusses the problem of loss of elastic properties of Pandrol Fastclip rail fasteners during operation. The research is related to predicting the dynamics of changes in the elastic properties of the Pandrol Fastclip clamping terminals during their long-term operation and provides for the creation of control methods (regulation) by pressing the fastening terminals on the sole of the rails, which guarantees the safety of trains with set speeds. On the basis of the conducted research, the design of a device that increases the pressing force of the fastening terminals on the sole of the rails has been developed. This device will provide optimal parameters for attaching rails to the sub-rail base at all stages of railway track operation. At the same time, there will be no need to replace the expensive imported elastic terminals of the Pandrol Fastclip fastening in cases of a decrease in the elasticity of the terminals in the current path. The research results are relevant for dozens of foreign railways where modifications of the Pandrol Fastclip fastener are operated: Pandrol Fastclip FC, Pandrol Fastclip FCA, Pandrol Fastclip FE, Pandrol 350, Pandrol SFC, Pandrol 1520, etc. The proposed technology for carrying out work to improve the technical condition of the intermediate rail fastening structure will not require the provision of "windows" in train schedules, which will not affect the carrying capacity and capacity of the railway track and will not affect the delays of scheduled trains.

Issues related to the wear of the rail and wheel tread of a locomotive are always of great interest to both operational services and scientists. Knowledge of the influence of technical and operational factors on the intensity of wear of the materials of the contacting bodies would save material and financial resources. The proposed article is devoted to determining one of these parameters, namely, the depth of indentation of the material of the rail head into the material of the wheel rim flange. The force interaction of the bandage crest and the rail head occurs mainly at the level of irregularities in the contact area. The wear of the material of the contacting bodies will be determined by the depth of penetration of irregularities in the contact area and the speed of relative slip. An important parameter for assessing the magnitude and nature of wear is the relative penetration depth of the contacting bodies. In this case, the magnitude of the collapse of one of the contacting bodies is equal to the depth of penetration of another body into it. Calculations of the main radii of curvature of the surfaces of the rail head and bandage crest at the point of their contact are made, and the dimensions of the contact area are determined. As a result, expressions were obtained for calculating the depth of mutual penetration of the materials of the shroud crest and the rail head. The rail head material has a deeper penetration into the shroud tongue material. The force contact between the bandage crest and the rail occurs mainly within the limits of plastic deformation of their materials. Formulas are obtained for determining the magnitude of the approach of the contacting bodies and the highest normal stress in the contact zone. An estimate of the values of the collapse of the material of the rail head and the bandage crest was made, which makes it possible to judge the percentage of their wear. With force contact, the wear of the wheel rim flange is much higher than the wear of the rail head.

In this paper we consider an alternative method to solving problems of technical diagnostics of railway wheels, which consists in developing a system for monitoring critical states of near-surface layers of metal, which has the ability to detect incipient defects in the metal structure of the rolling surface of a wheel.

The necessity of searching for new methods to improve the dynamic rationalized properties of the traction drive, which does not create contradictions between the conclusions based on the results of numerical parametric analysis and the results of the analysis of nonparametric factors, is established. A modified base point method is proposed that takes into account the possible presence of areas of conservatism of a rational parameter and provides for a procedure for checking for conservatism. The search results using this method for a rational version of a traction drive with a support-frame suspension of an electric motor and a gear reducer coincide with the empirical choice of different manufacturers of locomotives.

In this paper we study the problem of interpolation signals neutral convolution vector. We propose an interpolation method, which has the best result in terms of even distribution of interpolation errors in the spectral region. Presents the results of a numerical experiment. The effectiveness of the proposed method in the sense of improving the accuracy of a discrete signal recovery in the receive path of the communication of railway equipment.

In microprocessor automatic block signalling (ABS) systems all the basic functionality is implemented in software. Current technique used by Russian educational organisations for training of engineering staff is solely based on functionality exploration of the microprocessor ABS equipment. We suggest that this approach is not sufficiently effective and could be improved. In our view, the improvement could be achieved by addition of extensive ABS algorithm development practice to the Railway Signalling Engineering curriculum. In this article, we present a prototype of a special microprocessor learning board, which supports development and debugging of various ABS algorithms. Along with the functional diagram, we give some technical details and present preliminary results of implementing and using this prototype.

In the paper the device for reactive power compensation for the electric locomotives based on passive adjustable compensator was described. This configuration of the compensator improve the power factor of the electric locomotive in all operational modes and raise value of the power factor to its maximum possible value. The management of the compensator unit is based on the extremum seeking control autonomous voltage inverter. Mathematical modeling of electric locomotive showed increase the power factor to a value of 0,98.

A method for predicting the performance of the current collection with increasing speeds using machine learning is proposed. Methods for obtaining statistically reliable data on the contact pressure of current-carrying electric rolling stock without the need for direct measurement based on design data and analysis of external factors (weather, operational) accompanying the interaction are considered.

The analysis of functioning of difficult transport systems is provided in article, the basic principles of use of simulation modeling in the organization of transportation process on railway transport are characterized. The method of creation of object-oriented model for the description of dynamics of interaction of cargo station and a way of uncommon use is considered.

This article is about technical and economic indicators of the operation of freight locomotives at the ranges of Russian Railways. The most attention is paid to such indicators as train mass, fuel consumption, technical and district speed. There is an analysis of technical and economic indicators during the period from 2010 till 2019. Based on the analysis of technical and economic indicators in the real mode of operation of freight diesel locomotives it's presented calculation of dimensionless train mass coefficients, fuel efficient use, district and technical speeds. The presented calculation fully characterizes as well using degree of technical and economic characteristics of diesel locomotives in of power and time as the effectiveness of system organization in their operation. To know the operating modes of diesel-generator sets of diesel locomotives in train work is source material for the analysis of technical characteristics of locomotive power equipment and making recommendations on their optimization in relation to operating conditions

The article deals with the distribution of the electrostatic field around the garland of porcelain suspension insulators containing defects. Achieved the distribution simulation of the electrostatic field around insulators in the software package Elcut. We get a picture of field distribution around the insulators for the environment with different dielectric constants. A comparative analysis of simulation results and experimental studies on the basis of which revealed the possibility of diagnosing the parameters of insulators of the electrostatic field.