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The article presents the results of research on the efficiency of the electric energy storage system in traction power supply on the example of one of the sections of JSC "Russian Railways". The results of measurements of electric values of electric rolling stock when moving along the railway section under study are considered. Based on simulation modeling, an assessment of the impact of power storage systems on the capacity of the railway section is obtained. Graphs of changes in the minimum travel interval and the minimum voltage on the current collector of an electric moving train depending on the power of the storage system, energy intensity, and threshold voltages for charge and discharge modes are constructed. An algorithm for the operation of the power storage system at a traction substation or linear device has been developed. Based on the simulation results, a graph of the degree of charge is constructed and a series characteristic is determined that allows maintaining the discharge depth at the level of no more than the specified one. Based on the results of calculations, the power, energy intensity and charging characteristics of the storage system are determined, which provide the required voltage level at the current receiver of an electric moving train within the boundaries of interstation zones.

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 article discusses the issue of improving the efficiency of converting units of DC traction substations. An algorithm for calculating electricity losses in converting units is given by the system-fixed effective values of the phase voltage of the primary winding of the transformer and the load current of each converter unit. Using the example of a conventional traction substation, an assessment of the influence of the operation settings of the regime automation of converting units on the loss of electrical energy is given.

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.

A variant of application of a contact compensated chain suspension with levers and lateral current collection for a three-phase traction power supply system (TSTE) is considered. Two different-phase contact suspensions are located on different sides of the track axis. The electric rolling stock must have two current collectors that press on the contact wire from the track axis in opposite directions. The description of the design of the contact suspension as a whole and the main components, in particular, the fastening of the rods, which makes it possible to provide a vertical zigzag and limit the transverse movement of the contact wire, is made. At points at the supports, the levers are connected to the consoles and have a knot to create angular rigidity. In addition, the rotation of these levers is limited towards the axis of the path and in the opposite direction. This prevents the possibility of lashing of different-phase contact wires. In accordance with this design, a mathematical model of this contact suspension was developed based on the finite element method, which provides calculation in statics and dynamics, taking into account the current collector. To describe the pantograph, a common three-mass model is used. Based on the analysis of the results obtained using this model, the influence of the design parameters of the suspension, cross wind and the speed of the pantograph movement on the quality of the current collection is determined, the limits of applicability of the suspension under consideration, depending on the value of these parameters, are established. It has been determined that, in contrast to a conventional contact suspension with a vertical current collection, for suspensions with a lateral current collection, a side wind has a significant effect on the quality of the current collection. It is the wind speed that is the main factor limiting the possibility of using a suspension with lateral current collection.

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 article deals with the issue of using electric power storage systems in railway transport. It is noted that they are used in renewable energy sources and on hybrid shunting diesel locomotives. The possibility of using electric power storage systems to improve the efficiency of using electric power for train traction is indicated. The introduction of electric energy storage systems in the traction power supply system is hampered by high capital costs and the need to strengthen several adjacent inter-substation zones at once. It is proposed to consider the possibility of creating a mobile energy storage system, all the equipment of which will be placed in containers installed on cargo platforms, which will allow such a system to be quickly moved. The purpose of introducing a mobile power storage system is to temporarily strengthen the traction power supply system during a planned overhaul or emergency repair of one of the tracks on double-track sections of the railway. In this case, there is a need for a batch pass of trains alternately in even and odd directions on the same track. The possibility of using a mobile energy storage system is considered on the example of a real section of the railway. For a given schedule of passing train packages, the dependence of the storage capacity taken off from time, the maximum power and the nominal effective energy intensity of the storage system are determined. An estimate of the electricity storage system cost is given. It is shown that more than 70 % of the total cost of the electricity storage system falls on the imported energy conversion subsystem. It is concluded that it is necessary to develop domestic converter subsystems.

The contact network is one of the most vulnerable elements of the traction power supply system. The prevailing number of events in the power supply sector is connected with the contact network. The article is devoted to the method of contactless diagnostics of the contact network of electrified Railways. The paper proposes to use a method for diagnostics of the contact network based on optical elements, followed by digital data processing and calculation of geometric parameters. This method is characterized by a low cost of the device in contrast to analogues and high accuracy of calculation. The analysis and selection of optimal installation locations for optical devices is given. The method of contactless diagnostics of wires of the contact network of electrified Railways is presented.

The article discusses methods in evaluating the current settings for turning on and off the second converter unit when introducing power backup systems for DC traction substations. The analysis of the advantages and disadvantages of existing methods. The algorithm for calculating the current settings. A comparative analysis of the operating currents of the automation of the converter unit is carried out on the example of traction substations of the current section of the West Siberian Railway.

The article deals with issues related to theoretical and experimental studies of operating modes of the traction power supply system. The analysis of the comparison of voltages on the tires of traction substations with uncontrolled rectifiers and tires of traction substations with converter units equipped with a system of non-contact automatic voltage regulation is shown, the differences between them are shown. The modes of operation of the active partitioning post with the point of increasing voltage have been studied in detail. As a result of research, it was found that the observation time of maximum voltage values at substation tires above the average no-load voltage level is about 5 -10% of the time of day, about 7 - 8% at active posts, and 10 - 13% at passive posts. The maximum power in the active mode of the post sectioning with the point of increasing the voltage at lower voltage in the contact network is 2.9 MW. The average amount of electricity returned to the contact network point of increase of voltage, in one case is 170 kWh. The average duration of work in active mode for one case is 8,6 minutes.

Transfer of railway lines on the high-speed movement demands strengthening of traction power supply system.Such strengthening can be carried out on the basis of symmetrizing transformers and coaxial cables use.Means of computer modeling of such networks which can be realized on the basis of the methods developed at Irkutsk state transport university are necessary for the solution of practical application of traction networks with the symmetrizing transformers and coaxial cables.Complex technical solution including both from the designated ways of traction power supply strengthening is of interest. Strengthening provides the additional effects consisting in improvement of electric power quality in the feeding high-voltage networks and not traction consumers' power supply,and also in decrease in losses of the electric power and energy efficiency increase. Results of computer modeling of 2х25 kV traction power supply systems with Woodbridge symmetrizing transformers and coaxial cables are given.Modeling was carried out for three options: traditional scheme of 2х25 kV traction network; traction power supply system equipped with the modified Woodbridge transformers; the complex technical solution which is included the symmetrizing transformers and coaxial cables. Modeling results have allowed the following conclusions: application of coaxial cables promotes increase of contact net voltage; due to use of Woodbridge modified transformers it is possible to lower significantly negative sequence asymmetry factor on high voltage buses of traction substations; the greatest effect takes place at complex use of the symmetrizing transformers and coaxial cables.

The article analyzes the influence of parameters and operating modes of traction power supply system on the value of the useful energy recovery and the amount of electricity losses caused by the energy recovery through the traction power system to various consumers. The amount of energy lost in recuperation determines the degree of efficiency of its use. The approaches to the sequential determination of the recuperation energy efficiency and the calculation of the numerical values of the quantities characterizing the parameters of the traction power supply system, which are necessary for an adequate analysis of the energy distribution flow distribution, are proposed. It is determined that it is sufficient to use the regression analysis method to estimate the influence of the parameters and operating conditions of the traction power system on the energy efficiency of the recovery. The values of the relative resistance of the contact network are calculated depending on the type of the contact suspension, as well as on the traction network supply circuits. It is shown that the parameters and operating modes of traction power supply system affect the losses in the contact network, the losses in rectifier-inverter converters and traction transformers of direct current traction substations, the amount of energy recovery from tires of traction substations, as well as the relative change in losses in the system traction power supply with the use of regenerative braking.

Researching subject which are presented in article is the emergency modes in 25 kV traction power supply systems caused by the short circuits (SC). The research purpose consisted in the analysis of calculation SC currents errors evolving from the reactances determined by SC power at the simplified modeling of external network. For achievement of formulated purpose comparative calculations of SC currents for a number of standard schemes of 25 kV system when using full models in phase coordinates and with use of simplified electric power system (EPS) reactances are executed. Modeling has shown that calculations of SC currents of contact network of deadlock substation by EPS reactances give the acceptable accuracy for feeder current of substation near which there is a short circuit. The calculation error of remote substation feeder current can reach +100% at SC power on inputs of substation about 300 MV·A, but decrease to values about 10% at the SC power of 2500 … 3000 MV·A. At food of group of traction substations from two 110 kV lines calculation error for equivalent reactances it is much less, however at SC power about 300 MV·A errors reach 35% and decrease to 10% at SC power on substation inputs more than 550 MV·A. Variant of traction substations power supply from two 220 kV power lines differs in small calculation errors of SC currents for equivalent external power supply reactances: differences from full scheme don't exceed 9% at SC powers of 1200 MV·A or more. The received results can be used at improvement existing and creation of new definition techniques for SC currents in 25 kV traction networks.

The analysis of wave processes in the system including electric transmission lines, traction substations, AC traction network and electriclocomotives is necessary to accurately assess to energy performance of its work. This system contains concentrated and distributed parameters, consequently the analysis of such a system is difficult and the rolling stock which is also a part of this system represents a dynamic load. The proposed mathematical model of the alternating current traction power supply system allows us to consider electromagnetic processes at its various points taking into account wave processes.

In article the issues of electric power imbalance in train traction research are considered, including the method providing an estimation of the contribution of imbalance components to its total value with the possibility of their separation between the participants of the transportation process: the electrification and power supply service, the automatics and telemechanics service, the directorates of locomotive traction and motorized rolling stock. Described method allows in more detail to analyze the factors that affected the change in the components of imbalance and further develop organizational and technical measures to reduce it.

The aim of the research presented in the article was to develop computer models for determining the electromagnetic fields (EMF) generated by three-phase 25 kV traction power supply systems (TPSS). In contrast to traditional single-phase TPSS, three-phase systems are electromagnetically balanced, provide symmetric loads of substations, increase voltages at current collectors of rolling stock, reduce asymmetry and non-sinusoidality in 110 - 220 kV supply networks. However, the issues of quantitative assessment of electromagnetic safety conditions in three-phase traction networks remain unstudied. To implement the formulated goal, we used the methods of modes and EMF simulation developed at the Irkutsk State University of Railway Transport, the distinctive feature of which is the use of phase coordinates; in this case, the models of TPSS elements are formed on the basis of lacelike equivalent networks. The simulation was carried out for three-phase TPSS schemes of different complexity, in which case the complex traction network was implemented by modifying the model of a real TPSS of one of the main railroads of Eastern Siberia. Simulation results indicated that compared to the typical TPSS 25 kV, the maximum electric field strength increases by 2.5 % in the three-phase system. The maximum value of the magnetic field strength decreases by 26 %. Similar indicators for average values are 2.6 and 19 %. The proposed methodology and the developed computer models can be used in the design of promising three-phase TPSS. In the conditions of power engineering digitization, the application of this technique in practice will allow to apply a scientifically validated approach to the analysis of electromagnetic safety conditions traction networks and to develop its improvement.

The paper discusses the use of automated electricity metering systems to control parameters of the traction power supply system in terms of speed and heavy movements. As the main control system offered an automated system for monitoring energy efficiency of transportation process. The results of testing of the system considered in the measurement example, the boundaries of the active area of railways DC Shalya - Podvoloshnaya Sverdlovsk railway.

The article discusses a problem of the efficiency of the regenerative braking’s increase on the DC railway section. For the detection of the causes of the decrease of the specific regeneration’s level on the area an algorithm is offered, which enables to determine the causes of the decrease of the specific regeneration’s level on the arbitrary monitoring’s area in view of the determination of the locomotive’s capacity for work, work parameters of the electric traction system and the executed graphic time-table. In the article the main phases of the algorithm’s work were considered by the example of the one of the railway sections.

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 outlines methodological approaches to assessing the effectiveness of measures aimed at improving the efficiency of recuperative braking application and the use of energy recovery. An example of calculating the energy efficiency of recuperation on a double-track section of direct current is given. The analysis of the influence of changes in such parameters of the section as technical and district speed of freight trains on the efficiency of energy recovery. The article presents the results of estimating the energy recovery components that form the economic efficiency of recuperation, and describes the approaches to predicting the change in this efficiency, depending on the change in the influencing factors.

Recently, for the analysis of complex nonlinear processes, more and more attention is paid to the mathematical apparatus of wavelet transform. This is due to the fact that unlike the traditional Fourier transform, the wavelet transform provides information about the signal under study in the time-frequency domain. The purpose of research is to analyze and simulate a non-sinusoidal non-stationary mode based on the packet wavelet transform, the use of this method for transmitting the digital data stream of the signal under study. The simulation was carried out using the software package Simulink. In the study found that packet wavelet transform with high precision allows to determine the presence of higher harmonics in the power system, the efficiency of using wavelet transform to compress digital data stream of the test signal.

The article deals with the modeling of the electric rolling stock and traction power supply system with the aim of solving the problem of reducing the electric power consumption for the traction of trains in the conditions of changing the schedule of freight trains. Simulation modeling is performed for the conditions of changing the mass of the train and the load on the axis. The description of the results obtained is based on regression models, the order of application of models in practice is given.

Paper is devoted to the development of an improved algorithm for calculating the traction power supply system for further practical implementation in order to improve the accuracy of calculations of the traction power supply system by combining traction and electrical calculations with considering the current train situation. The relevance of the task is due to the need to improve the accuracy of calculations of throughput and carrying capacity under the conditions of power supply devices with considering the criteria for energy efficiency of the transportation process. The available solutions to this problem in the form of ready-made software systems and algorithms are considered. A numerical experiment was carried out for the DC section in the program "Complex of calculations for traction power supply", which showed that the relative error that determines the convergence of traction and electrical calculations is from 1.6 % to 5.1 %. The main reason for the discrepancy is the insufficiently correct calculation of the voltage at the current collector of the electric rolling stock. An improved algorithm for calculating the traction power supply system is proposed. The distinguishing feature of this algorithm is the implementation of a clarifying full traction calculation before compiling instant schemes and instant electric and traction calculations. As a result of the research, a general algorithm for joint traction and electrical calculations with considering the parameters of railway sections and the current training situation has been developed,. A conclusion about the advantages of the proposed algorithm and promising directions for further research is made.

The paper discusses the main limiting factors limiting the volume of transportation of high-volume freight trains. Designated approaches to solving the problems presented by the use of compensating devices. The paper presents the method of selecting installation sites and the power of compensating devices in the traction network, taking into account the growth in traffic volumes, allowing to evaluate the positive effect of the installation of compensating devices on the prospect of increasing traffic volumes. Determination of perspective power consumption is proposed to carry out using power consumption forecasting. To assess the effect of the installation of compensating devices in the traction network, three criteria have been proposed: unloading traction transformers, increasing the voltage level at the consumer, and unloading the power transmission lines.