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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.

When modeling the traction power supply systems, reflecting the processes of interaction of electric traction power supply and mobile electrical loads (electric and electric) is one of the elements of movement imitation organization trains in space. The effect of moving trains in simulations (MI) in MatLab on schedule at the analyzed site traffic necessitates sequential switching models of electric rolling stock (EPS) to the traction network, so that its effect is realized by moving the site. However, in this case, there really is not the processes taking place in reality. This is due to the realization of the simulation method of discrete movements, characterized in that the CSE, one located on a cell - the traction network model at one time, thereafter jumps to another. While EPS previous cell is switched off and switched on the next cell. Thus there does not exist in reality switching processes that distort the results of the studies. Methods to reduce the negative consequences of such distortions are addressed in this article.

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.

The paper considers a traction power supply system with a voltage of 27,5 kV AC. In the MATLAB-Simulink software environment, a calculation model has been developed that takes into account the parameters of the external power supply system, the train schedule and the current consumption of the electric traction load in the inter-substation zone. It is shown that when choosing the power of the compensating device according to the average value of the reactive power consumed by one train, its passage through the inter-substation zone with direct current causes the same average power losses in the wires of the catenary as in the absence of a compensating device. An increase in the number of trains simultaneously located in the inter-substation zone with the same power of the compensating device entails a decrease in power losses in the wires of the catenary relative to a similar situation without a compensating device, however, the reactive power is only partially compensated. In the calculations of compensating devices, it is proposed to take into account the real existing train schedule, based on the probabilistic assessment of which the average daily reactive power consumed by the electric rolling stock is determined. In this case, it is necessary to take into account the power losses in the catenary. The use of unregulated compensating devices is advisable in areas with a constantly present load. When choosing step devices for transverse capacitive compensation, it is proposed to calculate their power based on a probabilistic analysis of the train traffic schedule and current consumption in the inter-substation zone. When the probability of the appearance of a certain number of trains exceeding 50%, the most effective are compensating devices, the power of which is selected on the basis of the average power consumption of all trains without taking into account the time of no load in the inter-substation zone, as well as two-stage devices, the power of the first stage of which is selected according to the current consumption of the two most likely occurrences of the number of trains.

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 drawbacks of the step-by-step automatic voltage control system under load AVC and the non-contact automatic voltage control system NAVC with the reactor switching device of the converter transformer used in the traction power supply are analyzed. The scheme of a thyristor-reactor switching device (TRSD) connected to the primary winding of the transformer is considered. A brief description of the operation of a transformer with TRSD and the procedure for calculating the symmetrical and asymmetrical external natural characteristics of a converter unit with TRSD are given. Based on the dependence of the energy indicators of the converter unit on the resistance of the uncontrolled reactor TRSD, a method is proposed for calculating the rational resistance of an uncontrolled reactor, where the power factor of the converter unit is taken as the criterion of rationality. The method includes two stages: the first is the calculation of the values of the power factor of the converter unit depending on the resistance of the uncontrolled reactor and the load current of the converter unit; the second is the determination of the average load current value of the power factor of the converter unit for each considered value of the resistance of the uncontrolled TRSD reactor and the determination of the rational for the considered external natural characteristics of the unit. In accordance with the presented methodology, the calculation of the minimum permissible and rational resistances of the uncontrolled reactor TRSD as part of a converter unit with a converter transformer TRDP-16000/10 was made. Taking into account the selected rational value of the resistance of the uncontrolled reactor TRSD, a calculation was made and the external natural characteristics of a converter unit with a TRSD and a converter transformer TRDP-16000/10 are presented. The performance check of the presented calculation method for solving the problem of choosing the rational resistance of an uncontrolled reactor was carried out on a physical model of a converter unit with a TRSD, with a 12-pulse rectifier unit, with a 30 kVA transformer and a linear primary voltage of 380 V. Comparison of experimental and calculated values showed a slight discrepancy, the permissible error was not exceeded. Determination of the resistance value of an uncontrolled reactor based on the developed methodology provides the highest values of the power factor of the converter unit.

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 describes the general principles of the computational model of the traction power supply DC Railway to assess the potential energy recuperative braking, as well as ways of approbation the resulting model to determine its adequacy.

The article analyzes the components of the energy efficiency of regenerative braking and the factors influencing the effectiveness of the use of regenerative braking and energy recovery. Methods of evaluating the energy efficiency of recovery and the results of experimental studies of the effectiveness of recovery. Achieved justification for the use of the method of simulation modeling as a method for evaluating the potential of regenerative braking. It shows the sequence of the work.

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.

Application intellectual networks (smart grid) technologies for electric power quality management in systems of alternating current railroads’ power supply are considered. The structure of intellectual traction power supply system is described. Classification of management technical means for electric power modes and quality is given. The algorithm of intellectual electrical power traction systems modes’ modeling is offered. This algorithm differs by sharing of imitating and dynamic models of the active smart grid elements in its basis. The modeling results confirm applicability of the developed methods for the solution of electric power quality management’s problems.

The article presents the main results of experimental studies within the boundaries of the Fadino - Novoseletsk, Novoseletsk - Strela interstitial zones of the Entrance - Irtysh section. As a result of the research identified problems that currently hinder the online monitoring of operational parameters of the electric rolling stock (EPS) and power supply devices: a lack of data on the work of the traction substations, the presence of EPS without registration motion parameters (RAPS), the lack of process data collection with RAP, the lack of a single source and process for obtaining data, insufficient memory storage device of cartridge, lack of data latch on the locomotive in General, lack a set of fixed parameters, non-constant sampling of parameter fixing, insufficiently detailed final documentation, imperfect software for exporting data from cartridges and lack of binding to global time. Shown the possibility of joining data from different automated systems of JSC "RZD" and measuring systems OSTU, which will allow us to estimate the losses in the traction network, the expense on own needs of electric rolling stock , the electric power consumption for traction and return of electric energy to contact network, as well as move forward with implementation of predictive control operation modes of the electric rolling stock and power infrastructure and Railways in a changing environment in the transportation process, to ensure the best conditions for the realization of tractive effort, regenerative braking, set train schedules, including in case of critical restrictions on the part of the power supply system, preventing train traffic from stopping.

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 technique of parametrical identification of alternating current railroad traction network is offered. The technique allows receiving trellised equivalent circuits of a traction network which in the presence of measurements’ errors of voltage and currents vectors which aren't exceeding 0,5 % 0,5º give rather high precision of systems modes calculation of traction power supply, providing the correct solution of many practical tasks. Computer modeling showed that uniform traction network mode errors on voltages don't exceed 0,4 % and 0.2º , on currents - 0,9 %, 1.3º.

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.