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An increase in the speeds of the electric rolling stock has an impact on the energy indicators of the operation of the traction power supply system. One of the technical solutions to the task of equalizing the traction load schedule to reduce voltage losses in the contact network is the use of electricity storage systems. The article presents the results of simulation modeling, which allow us to estimate the change in the energy indicators of an electric train with an increase in movement speeds for conditions of a single electric train following a section. According to the results of traction calculations, the influence of the voltage level on the electric train current collector on the technical speed is shown, the deviation of which for the typical voltage values in high-speed traffic is about 1%. For the selected section of rapid movement and technical speeds, the voltage level for traction calculations is justified. The dependences of the change in the average values of the load and the technical speed with an increase in the maximum speed up to 250 km/h are determined. Statistical estimates for the voltage on the pantograph of the Velaro RUS electric train are determined. The influence of the energy intensity of the onboard storage system with the corresponding charging characteristic on the reduction of maximum currents is shown. Dependences are obtained for the voltage drop on the electric train current collectors with an increase in movement speeds. The assessment of the maximum energy intensity of storage devices for the most severe operating conditions with a single electric train track on the site was carried out. These results allow us to determine the prospects for improving the method of calculating energy indicators and the use of accumulation systems in areas of rapid movement as on-board systems and compare their effectiveness with stationary systems based on simulation modeling, in which various control algorithms are implemented.

The calculation of the performance indicators of the traction power supply system in steady-state modes is focused on solving a wide range of tasks related to the choice of parameters of the power equipment of traction substations, the placement of linear equipment, the cross section of the contact suspension, the comparison of options for technical and economic indicators. Currently, the appearance of various regulated devices in the traction power supply system necessitates the improvement of calculation methods and algorithms used in various software complexes. In this paper, the issues of constructing substitution schemes for modeling the operation of the traction power supply system in steady-state modes, taking into account the devices for automatic switching on and off of the backup converter unit of the traction substation and the accumulation of electricity. The corresponding substitution schemes and fragments of calculation algorithms that take into account the characteristics and operating modes of these devices are presented. The use of the proposed substitution schemes allows us to take into account in the calculations the difference in the external characteristics of the converter units, to assess the compliance of the automation settings with the level of electric traction load and the effect of the device on the voltage level on the substation tires and in the contact network, the load capacity of traction substations, and for the accumulation device, taking into account the charging and discharge characteristics, to additionally assess the impact on the effectiveness of regenerative braking. The proposed algorithms of the devices are designed to improve the methods of calculating the indicators of the traction power supply system. The paper proposes an improved method for calculating the indicators of the traction power supply system, based on simultaneous traction and electrical calculations, based on the database of calculations performed for various conditions of electric rolling stock on the railway section.

One of the properties of the reliability of the power supply of electric rolling stock of railways is the trouble-free operation of the traction power supply system in various modes of its operation. For post-emergency and forced modes of operation of the traction power supply system, a decrease in load capacity is characteristic. In order to ensure the throughput and carrying capacity of the railway section by traction power supply devices, it is proposed to consider the use of electric power storage devices on electric rolling stock and in the traction power supply system. Studies conducted by domestic and foreign researchers allow us to evaluate the effectiveness of alternative solutions to improve the reliability of power supply, which include various options for the use of electric power storage devices on electric rolling stock and in the traction power supply system. This article presents the results of a review of these solutions, a simulation model of a traction power supply system and an electric rolling stock with power storage devices based on various batteries and a supercapacitor is proposed. Modeling of changes in the modes of operation of the traction power supply system is carried out taking into account the state control of switching devices. The calculation results allow us to estimate the voltage drop at the output of electric power storage devices, including taking into account the exponential zone of the discharge characteristics of batteries, to estimate the voltage change for a given electric traction load depending on the energy intensity of the storage device, made on the basis of the most common types of batteries and a supercapacitor.

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 presents the results of experimental researches of process of commutation in traction DC motors. In order to generalize the results of tests of low power engines for electric locomotive’s traction motors, belonging to high power engines, by using the theory of similarity and dimensions we defined the ranges of varying parameters of the operation mode in the experiments. In result of the conducted researches proved the effectiveness of the parameters of laws of distribution of intensity sparking to improve the reliability of the test as low power engines and high power engines.

Shotcrete lining is one of the most common types of temporary supports in tunnel construction. The influence of shotcrete lining on design calculations of permanent lining is difficult, because there is no method of designing at the present time. This leads to increasing in consumption of materials and labour of construction. The information about the influence of the basic mechanical properties of soils, geometrical size of construction per value of temporary shotcrete lining factor was obtained during research. These data formed the basis for futher development method of designing. Empirical correlations of stress distribution between temporary shotcrete lining and permanent monolithic reinforced concrete lining were obtained during theoretical research. Results of experimental research tensity of temporary shotcrete and permanent lining confirmed the possibility of using in the designing this empirical correlations. Using in the designing proposed empirical correlations will leads to reduction in consumption of materials and labour of construction.

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.

In this article, the process of wear of the material of the ridge of the wheel brace during the movement of the locomotive in a curve of a given radius is considered. The methodology of the study considered in this article was that, based on the expression for the depth of penetration of the rail head into the material of the bandage ridge, the movement of the wheel along the inner rail in the curve was considered. It was taken into account that the contact point on the ridge of the bandage will move along the edge of the rail with slippage and that the contact area is a fairly narrow surface with a border close to an ellipse. Formulas for calculating the speed and the slip path of the contact point of the ridge of the locomotive wheel brace with the rail are obtained. As a result of the study, equations were derived to estimate such quantities as the volume, intensity and wear rate of the bandage (per revolution of the wheel). It is shown that the expressions obtained as a result of the work carried out can be used to calculate the intensity of wear of the brace ridge when the locomotive is moving in a curve of a given radius. The amount of the ridges material wear of the wheelset bandages can be determined on the basis of the equations obtained individually for a specific locomotive series and a given range of its operation.

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.

In research consider a methodology the remaining life assessment of rail with fatigue crack in lower flange. Obtain the stress intensity factor equations for crack size and kind of stress: bending stress, thermal and residual stress. Make up an fatigue strength analysis of rail P65 and under different conditions of loading and remaining life calculation of damaged rail when given conditions of loading. Submit a assessment evaluation rail reinforcement in cyclic crack growth rate.