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On the basis of experimental data thereis a mathematical model in thisarticle. Its made from the registration options in acfual operation mode of the locomotive. This mathematical model describes the technical condition of the locomotive and evaluates the parameters and characteristics. Considerable attention is paid to complex state operation of the facility. In dealing with the mathhematical model it’s defined the main locomotive operation indicator.

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

In article the reasons of shutdowns of high-speed switches of a direct current are analysed and distribution of the disconnected currents is received. Such numerical characteristics as population mean and a mean square deviation of function of distribution of the currents which are disconnected by the high-speed switch are considered. The hypothesis of distribution of probability of refusal in operation of the switch is checked. Conclusions are drawn on applicability of the given calculation methods for definition of admissible number of shutdowns of high-speed switches on sites of traction network of a direct current.

Analysis of the causes of errors of measurement of phase shifts of harmonic components in electrical railway traction networks and describes how to improve the accuracy of measurement.

The factors affecting the operational reliability of the assembly platform of a rail service car maintaining the repair and installation on the railways are considered in the paper. An assessment and analysis of a system of quantitative indices of reliability is performed, the methods for their separate determination by mechanical equipment and hydro and electrical equipment is described. The strategy of maintenance and repair combined with the use of methods and means of a modern diagnostic system is considered; it ensures the estimation of the object reliability during its design, operation and repair.

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

Is executed the analysis of the permissible range of the fluctuation of the phase of signal on the entrance of digital measuring device with a study of phase relationships in the tractive networks of the power supply of rail transport, characterized by high noise level.

In the work completed a study of shape vertices a unimodel probability density function (kurtosis) on the output of the nonlinear converter «phase shift - code, which is the most important parameter for evaluating conditions of finding mode to this function. To increase the accuracy of assessment shifts phases when there is high level of random noise is defined not only quality, but also quantitative dependence of the kurtosis probability density function on the output of the nonlinear converter «phase shift - code» of Standard deviation phase fluctuations of the signal at its input. The mathematical model of the distribution function on the output of the converter «phase shift - code» for research and implementation of algorithms improve noise immunity measure phase shifts between harmonic components of voltage and current in traction power supply rail transport networks.

In work done modeling and analysis of noise immunity of the proposed measurement method of phase shifts between harmonic components of voltage and current in traction power supply rail transport networks and estimation of maximum permissible noise level, where workability digital devices used to study phase shifts in these conditions. The simulation results have shown that the probability density function on the output of the nonlinear converter «phase shift - code» remains a unimode at any ratio range converter and standard deviation of the phase of the input signal. Implementation of researched ways of microprocessor-based digital device guarantees the stability and accuracy of measurement results in traction phase shifting networks of power supply of railway transport in the presence of high levels of industrial noise, nonlinear fast variable nature of the traction load, sparking the pantographs for electric locomotives in contact network and use recovery systems based on pulse converters.

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.