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The aim of this article is results representing of work focused to automation of electrical machines armature coils diagnostics process based on wave response method. Technical decisions used in development of mobile device for insulation diagnostics via wave response method described. Techniques of generalized diagnostics coefficient calculation described. Article presents test results of NB436V and NB-431P auxiliary machines installed VL-10 electromotive.

This paper describes an algorithm evaluating the effectiveness of energy-saving devices and technologies, based on the methods of mathematical statistics. Diagram presented in the article. It can be applied in the traction system and power supply without traction. Approbation of the algorithm is executed in the traction power supply system. The developed algorithm includes five stages: 1. Stage calculate the required number of observations. The basis of this stage is to evaluate the dispersion and calculating on it the desired number of observations. 2. Stage of the collection and processing of data obtained before the implementation of energy-saving devices and technologies. Collection is carried out on of electricity consumption and factors influencing the process of electricity consumption. Processing includes the calculation of the correlation matrix, the coefficients of determination and the parameters of the regression equation. 3. Stage of the collection and processing of data obtained after the implementation of energy-saving devices and technologies. Data collection is carried out according to the parameters selected in step 2 and the processing is done by the calculation of the parameters of the regression equation. 4. Stage of comparing the data before and after the introduction of energy saving devices and technologies. Comparison of the data obtained before and after the introduction of energy saving devices and technologies produced using the Chow test and nonparametric mathematical statistics such as omega-square (Lehmann-Rosenblatt). 5. Stage of calculating electric power saving. The calculation is made on the consumption of electricity obtained by the regression equation before the introduction of energy-saving devices or technology by substituting the values of the factor after implementation and actual consumption of electricity after the introduction of energy-saving devices or technology. Approbation of the algorithm was successful.

The article presents statistical studies of acoustic control signals when diagnosing power transformers of the railway power supply system. Statistical processing of acoustic monitoring data was carried out on the example of transformers with different levels of insulation condition. Comparisons of histograms of the experimental distribution of amplitudes and dominant frequencies of signals with the nearest theoretical distribution laws, performed in the STATISTICA program according to control data obtained from the automated system. The conducted studies have shown a close correlation of defects registered by the acoustic method with the distribution of signals in the form of laws of distribution of random variables. It is shown that for power transformers with mechanical oscillations, both during the passage of the train and at idle, the distribution of amplitudes and dominant frequencies of the recorded signals corresponds to a uniform law. The distribution of amplitudes and dominant frequencies is not centered around a certain average value. For power transformers containing partial discharges, the cause of which is the deterioration of the insulating properties of the windings under the influence of high voltage, the best approximation, both amplitudes and dominant frequencies, showed the Lognormal distribution. The signals are centered around a characteristic mean value. When the train passes, the acoustic system registers both high-frequency signals from the PD and low-frequency signals from body vibrations. There are two components in the distribution law - uniform and lognormal distribution densities. Thus, by the type of distribution of the recorded signals, their amplitude and dominant frequency, it is possible to determine the presence of a defective state of the insulation of power transformers. The study was carried out with the financial support of the Russian Foundation for Basic Research within the framework of the scientific project No. 20-38-90231.

The article deals with the problem of diagnosing the technical condition of the collector-brush unit of DC motors. The topicality of this problem in the engines operating on the railway transport, which are in the most severe operating conditions, is particularly noted. These studies are aimed at improving the reliability of diagnosing the technical condition of the collector-brush unit through the use of a new method of diagnosing the condition of collector DC motors’ commutation. The proposed method of diagnosis is based on a new principle of processing diagnostic information about the spark pulses under the brushes. The article presents the histograms of the distribution of the pulses' intensity of different sections of the armature winding. The research conducted an experiment using a digital control device that allows to identify and digitize a useful diagnostic signal from multipolar brushes with a high sampling rate and transfer it to a computer. Analysis of the experiment’s results showed that the average value of the pulse’s area increases with increasing the spark’s intensity. Nevertheless, severe sparking at the collector leads to the law of distribution becomes double-modal, and as a result, dramatically increases the standard deviation of the values of the pulses’ areas. Described effect makes misinformation in the diagnosis procedure using the parameters of the laws of distribution of the spark’s intensity. The proposed method of diagnosis allows to eliminate this effect. The copyright for a new method of diagnosing is protected by a patent.

The article proposes a method for increasing the efficiency of power supply systems for non-tangible consumers due to quadratic accumulation of electric energy on reactive elements in the frequency-beating mode. The proof of the energy efficiency of the beating regime in comparison with the full resonance regime with respect to the implementation of quasiresonance pulsed power supplies is given. The article also deals with the choice of the optimal beat frequency by the criterion of the maximum ratio of the accumulated energy on the reactive elements of the circuit to the one expended from the primary source.

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.

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 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.

The main engineering problem associated with the degradation of permafrost and cyclic freezing-thawing of seasonal permafrost soils is a decrease in the bearing capacity of engineering structures due to the degradation of the main physical-mechanical properties of the embankment soils. The cyclical change in temperature leads to regular freezing-thawing of the soil, as a result of which such types of deformations occur as heaving during freezing and settlement during thawing. The purpose of this work is to highlight new information about complex measures to stabilize the subgrade of railways and highways in the cold regions of China. The paper considers such measures as thermosiphon stabilization, rock fill, installation of ventilation pipes and laying of thermal insulation boards. This paper also describes the disadvantages of existing measures for stabilizing the temperature regime of the embankment and its base. Considered the main transport network of the Qinghai-Tibet plateau, including the Qinghai-Tibet railway and four highways. The experimental section of the Wushu-Xining expressway on the Qinghai-Tibet plateau was chosen as the object of the study of numerical modeling; a numerical calculation of the temperature and moisture content fields of the typical embankment was carried out, as well as numerical calculation of the embankment with rock fill for the 10th year of operation. The calculations were carried out on the basis of the «Freeze-Cold» software package specially developed for engineering calculations of the freezing and thawing process in soils. The calculation showed that rock fill allows to reduce the area of the soil thawing, raising the front of frozen soil, helps to reduce the degradation of frozen soil, which ultimately has a positive effect on the bearing capacity of the entire engineering structure. Analysis of the collected data and calculated values allows to conclude that the use of rock fill of 0,8 meters depth as an insulating material to maintain the stability of the thermal regime of the embankment on frozen ground in the considered region of the Qinghai-Tibet Plateau.

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

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.

In article methods of valuation electrical parameters and mathematical models of electic processes of reinforced concrete construction are considered. The conclusion that influence of reinforced mesh was not taken into account in describe models had been done. Method for prediction of reinforced concrete foundation which based on equation system of electric field in conductors and finite element method and allowed explicit geometry of object include reinforced mesh was suggested by authors. Authors done the assumption about invariability of potential of reinforced mesh which covered of concrete layer for direct current and alternating current due to ratio of steel and concrete resistance. Realization of nethod was done by dint of software complex Comsol Multiphysics. Research object was reinforced steel foundation TSS-4, which is located in ground. Result of research was represented color epure of potential distribution and line of current density. Reinforced concrete construction current and current which flow into armature were determined by dint of integration of normal current density on surface where set the external potential and surface of armature. On the grounds of determine values of model current resistance of model depending on resistivity of concrete and ground were calculated.

This article presents an algorithm and a method for calculating power flow of an open electric network with a voltage of 6-35 kV, taking into account the temperature dependence of active resistances. Calculation of the electric and thermal conditions of the electric network is carried out with a joint solution of the equations. The determination of stresses in the nodes is carried out using the inverse matrix of the nodal and intrinsic conductivities. The inverse matrix of nodal and intrinsic conductivities is determined based on the well-known direct Jordan-Gauss method. The equation of the heat balance of the wire used to calculate the actual temperature is solved numerically. Convective heat transfer is recorded only for forced convection, because wires of overhead power lines with a voltage of 6 kV and higher are located on various types of poles, at a height of at least 10 m. This fact allows us to abandon the use of formulas for natural convection and use expressions only for forced convection. Accounting for solar radiation in the presented algorithm is possible on the basis of two methods: simplified and considered in the standard of PJSC FGC UES, which allows you to take into account the actual location of the wire relative to the north. Using the test circuit as an example, the steady-state mode was calculated taking into account the temperature dependence of the active resistances. The results of a numerical experiment are presented, confirming the operability of the developed algorithm. The refinement in determining active power losses with and without taking into account the heating factor for the considered circuit is about 13%. Verification of the algorithm that implements the method of calculating the steady state (SS) of an open electrical network of a medium voltage class taking into account the temperature dependence of active resistances showed that in technically acceptable modes the developed algorithm has good accuracy in comparison with the RastrWin3 software package.

Special attention on the Belarusian Railway is paid to the issues of operation of curved-linear sections of the track, since in the framework of solving the problem of increasing train speeds; one of the significant obstacles to changing the speed regime is the discrepancy between the actual position of the curve of the project documentation. The automated systems of mobile diagnostic tools used on the road fully allow us to evaluate the actual parameters of the curves, which can form the basis for modeling the desired positions of the curves for the purpose of their certification. For this purpose, various orders and orders are drawn up annually, which set the main parameters of the curves in the plan and level, as well as the volume of work on the reconstruction (modernization) of the curves in order to bring them to the project documentation. In the Methodology introduced at the Belarusian Railways for evaluating the actual parameters of the installation of curves of track sections, general provisions given for the regulations that determine the procedure for performing actions when performing qualitative and quantitative assessments of the parameters of the geometry of the rail track. Depending on the state of the actual parameters, it is assumed that the curve will be assigned a certain status, which determines the order of its further operation, and depending on the ratio of the actual parameters relative to the design parameters, the degree of violation. The parametric analysis of this technique allowed us to generalize the results of structural, functional and informational analyses of the order of assessment of the level of disorder of curves, with assigning them the appropriate status, and the value of indicators that determine the degree of violation. The study of the parameters of curved sections revealed discrepancies in the qualitative and quantitative estimates of the same track sections, as well as the need for a comprehensive assessment of the actual and design parameters of the rail gauge geometry.

The article describes a software module of the initial image processing which allows to perform the contour image analysis in order to find, recognize and evaluate graphic images of various types of inhomogeneities. Application of software module will improve the accuracy of the evaluation of the internal surface of closed vessels in the absence of access control.

The article is devoted to finding ways to improve the maintenance of infrastructure. And suggested the expediency of refinement tools used methodology Urra, allowing significantly taken into account in the risk assessment process imperfect operation of the infrastructure associated with the influence of the «human factor».

The models of complex organizational and technological parameters of operation of liner-straightening machines cyclic action on the example of the VPR-02 and VPRS-02 using a probabilistic assessment of the reliability of their work. For her study conducted two etapa checks: logical and mathematical. After sampling in accordance with GOST 8.207-76 inspect it belongs-rise normal distribution using Pearson's chi-squared test. Next calculated reliability and risk completion of the planned scope of work machine systems, complexes, components and individual machines in the planned period of time. The models are based on actual field tests of databases, technical and economic indicators of machines, components and systems in real operating conditions. This model optimizes track works with a given reliability at stave-builder, all kinds of repair and current maintenance of railway track. And also give the opportunity to the WHO-define more rational modes of operation of track machines for you, edits, tamping and straightening the railway line, thereby increasing pa O-workings of these machines. They enable organizations operating these machines more reasonably expect the required number of cars processes track works, their cost and labor. The proposed method models quantify the technical reliability of the liner-straightening machines; allow predicting the main complex organizational and technological performance of a particular machine at the design stage of technological processes track works. This method is versatile and can be used to evaluate the technical reliability of any machine systems, components and separate machines.

The article presents a nonlinear mathematical model of heating a two-layer body with allowance of the finite velocity of heat propagation and the temperature dependence of the properties of materials. A numerical solution of the nonlinear hyperbolic heat conduction problem is obtained for the case when the absorption of the radiation energy is modeled by a volumetric heat source. The implementation of the grid method using a three-layer implicit difference scheme in solving a nonlinear heat conduction problem in a two-layer body with allowance for the relaxation of the heat flux and the conjugation conditions in the case of ideal contact at the interface junction is considered. The described algorithm for calculating the temperature field for high-intensity heating of a coated body, taking into account the dependence of the thermophysical characteristics of materials from temperature, is based on the implementation of the sweep method with iterative correction of the coefficients. Programs are developed and the results of calculating the temperature fields are presented using nonlinear hyperbolic heat conduction equations and the corresponding linear ones taking into account the average integrated thermal and optical characteristics of the materials. Based on a comparison of the results obtained the necessity of taking into account the temperature dependence of the properties of materials during the study of processes of high-intensity heating of bodies.The developed mathematical model on the basis of a system of nonlinear hyperbolic equations can be used to create technological processes using methods for processing the surface of multilayer bodies by laser radiation.

The article is devoted to numerical methods for solving nonlinear heat conduction problems with considering for the relaxation of heat flow. A mathematical model is developed on the basis of a non-linear heat equation of the hyperbolic type for calculating the temperature field in an infinitely extended (unlimited) plate. The implementation of the grid method using a three-layer implicit difference scheme for solving the nonlinear hyperbolic heat conduction problem is presented for the case when the absorption of radiation energy is modeled by a volumetric heat source. A numerical solution of the nonlinear heat conduction problem in an unbounded plate is obtained taking into account the relaxation of the heat flow on the basis of the finite difference technique using the sweep method and iterative refinement of the coefficients. A calculation algorithm with a graphical representation of the results of calculating the temperature field in an unbounded plate under the influence of concentrated energy flows is described. A comparison of the results of calculations of temperature fields in mathematical modeling on the basis of the nonlinear hyperbolic heat equation and the corresponding linear model using the mean integral values of thermophysical and optical characteristics is presented. The significant differences obtained between the temperature fields corresponding to the nonlinear and linear problems justify the need to take into account the temperature dependence of the thermophysical characteristics and the absorptivity in the study of high-intensity processes of heating the bodies. The developed nonlinear mathematical model of body heating with allowance for the finite speed of heat distribution and the temperature dependence of the material properties, can be used to select the modes for processing mode bodies with high-intensity energy flows.

Substantiated the application of the probabilistic analysis of the break-even on the basis of a Monte Carlo method for the study of freight as a complex stochastic systems. Analysis was carried out on the basis of data of the Ulan-Bator railway.

The article deals with the locomotive lifecycle problem at vehicle technical maintenance and repairing service. It proposes to encapsulate the statistic methods into the automatic locomotive depot control system basing on the example of management with the minimum stock spare parts level. In such a group of companies as "Locomotive technologies" the efficacy of maintenance and repairing technological processes is improved by creation and implementation of the information management control system "Network diagram" into the locomotive depot service. Its implementation was started in 2016 and should be completed by the end of 2017. In practice methodological approaches of international (ISO) and national (GOST) standards of management quality and reliability, lean manufacturing and statistic methods of management in conditions of locomotive depot service are proposed to be used basing on the principle of "Built-in quality". In this case logical constructions, algorithms and formulas are encapsulated into “Network diagram” software significantly reducing the training level demands of the depot personnel. The article also proposes to control the minimum level of stock spare parts in the locomotive depot in terms of “Network diagram” software through encapsulation of probabilistic-statistical methods of minimum stock calculation according to the data on intensity of parts consumption and the time of their delivery to the depot.

The article presents the results of the development and implementation of a method for controlling the technological processes of repairing locomotives based on network planning. The methodology allows you to track online bottlenecks during current repairs and reduce the duration of the critical path by varying the time indicators of events and works, using the aggregate-nodal repair method, redistributing resources between critical and non-critical works. The developed methodology is based on the adjustment of basic repair networks, taking into account the workload of process equipment and repair personnel, the availability of spare parts and materials, the need for unscheduled work during the planned installation of a particular locomotive for repair. This approach was implemented within the framework of the automated control system (ACS) «Network Schedule» and provides control and adjustment of the implementation of technological operations according to the indicators of technological preparation of repairs. An algorithm has been developed for determining a generalized performance indicator when assessing the quality of functioning of an automated maintenance and repair control system for a locomotive in service locomotive depots.

The authors consider the question of the limits of applicability of the capacitor method for measuring the real part of the dielectric constant of printed circuit boards and telecommunications cabled rail transport using the example of FR-4 fiberglass laminate and the cable PK-75-4-12 in the frequency range from 10 Hz to 100 MHz. The measurements were carried out at a constant temperature and humidity of a known material. Comparison of the obtained values with the passport data on the material is carried out; a measurement procedure is developed with overlapping frequency ranges by changing the values of the measuring resistors from larger to smaller with increasing frequency of the input signal. It is shown that in the high-frequency region, the measurement accuracy is directly affected by the parasitic inductance of the capacitor sample under study, as well as the active resistance of the leads and plates and its increase due to the skin effect. The article also discusses the ways of accounting and calculating the parasitic elements of a capacitor. One of these ways is to study the characteristics of the elements of the sample at the first proper serial resonance of the capacitor under study.

In the article presents the network model of processes of planning and the accounting of transportations, and also processes of execution of documentation at freight dispatch in the intra republican message of the railroads of Uzbekistan by means of composite document management. Composite document management provides the movements of documents in paper and in electronic medium, and also their composite decisions. The special the automated system (AS) will support processes of electronic document management and to make the reporting in the automated mode. For mathematical modeling of process of document management in this work it is used methods of network planning and management. It is described characteristics of the offered technology of planning and the accounting of transportations, and also execution of carriage documents at freight dispatch in the intra republican. It is applied, the PERT method for calculation of accidental temporary characteristics of works. Temporary characteristics of events are determined by a method of a critical way. Tables with the sequence of works with the indication of optimistic, probabilistic and pessimistic assessment of duration of performance, and also with results of calculations for determination of average time and dispersion are made. The network schedule of works, in compliance of technology of document management by means of which terms of performance of work are evaluated, entering document management process is made. Durations of critical and noncritical ways are determined. The results received in article confirm efficiency of the offered technology of document management. Use of this technology providing filling of documents electronically and fixing with the digital signature (DS), it is expected to lower expenses of time of consignors and the railroad, to increase productivity of works and quality of the provided services, to create the centralized information base.

In this article the tasks of simulation of flows on the railways are discussed. The main purpose of this work is to create a new simulation technology such a complex system as the rail network. Scientific novelty consists in the application of a combination of agent-based and discrete-event approaches in a given subject area. During the conducted study the models of behavior of agents were created, the problematic situation was highlighted and discrete-event part of the model was developed for this situation. The main categories of regular and emergency situations are analyzed, a list of situations for modelling are created. Choices for removal emergency situations were discussed, an algorithm for their processing (discrete-event part of the model) was chosen. An illustration of the study is a simulation model of the railway section of the West-Siberian railway with the possibility of rebuilding the train schedule, which depend on the addition of regular or emergency situation. As a result of the simulation, output such as a traffic graph and an information table are generated. There are plans to use new technology for creating model of "transport hub”.