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The purpose of this article is to analyze the voltage drop in the contact network caused by poor-quality operation of an alternating current electric locomotive when passing heavy trains. Heavy-haul traffic is considered today as a valid and necessary tool for increasing weight norms and increasing the throughput of railway sections. The article provides statistics on the passage of heavy and connected trains on the Krasnoyarsk railway for 2019 and 2020. For the effective use of heavy traffic, it is necessary to solve a number of problems, one of which is to reduce the voltage in the overhead network when passing heavy trains, this negatively affects the speed of the train along the haul, the conditions for cooling the power equipment of the electric locomotive deteriorate, etc. As a result of the analysis of the operation of the thyristor rectifier-inverter converter, a number of disadvantages were revealed. The reason for the low power factor of the electric locomotive lies in the use of an outdated element base based on thyristors, their closure is carried out only in the next voltage half-cycle, long-term switching and a large opening angle of thyristors leads to a significant reactive current in the contact network. Based on the analysis the voltage losses at the current collector, it was concluded that it is necessary to reduce the duration of the switching process of the arms of the rectifier-inverter converter, in which a short circuit occurs in the secondary winding of the traction transformer. An alternative version of the converter based on fully controlled semiconductor devices - IGBT transistors is proposed. The ability to open and close at any time of such elements allows you to minimize the phase angle and increase the power factor. Due to the almost instantaneous switching of transistors, the distortion in the contact network is minimized.

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.

Results of the analysis of normative and legal documents of the Russian Federation, and also the internal normative documents establishing the main target indicators and requirements to activities for energy saving in «Russian Railways» Holding are given in article. Need of carrying out updating of Power strategy of «Russian Railways» Holding and revision of the list is proved by the mechanism of its realization.

In this paper, the possibility of controlled shunt reactor (CSR) to absorb excess charging capacity in long lightly loaded transmission lines of 110 kV electric networks Nordic branch of JSC "IDGC of Siberia" - "Omskenergo." The emergence of excess reactive power leads to an increase in the voltage at the nodes of the power system and the emergence of significant power loss. The application of CSR, The calculation of the required power, the place of installation, pre-feasibility study.

The article describes the types of irrational electric power losses for train traction and sets the annual planning levels of their improvement. Represented the basic methods of irrational electric power losses determination which are currently used in JSC "Russian Railways". Shown an example of the irrational losses determining algorithm in case of making up for train delay and given its description. Formulated technical results of the proposed method for determining the irrational electric power losses .

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.

According to electric calculations, the overhead system and power lines being the part of the railway power supply are distributed parameters circuits. Wave processes in the overhead system have a negative impact on the power supply lines, laid in the vicinity of the railway, and increase the power losses in the traction power supply system. For the study of wave processes the method of mathematical modeling of non-sinusoidal signals transmission to the uniform two-wire distributed parameters line is provided. The mathematical model is based on the well-known line differential equations (telegraph equations) using Fourier series. The power line is a three-wire line. The paper presents an algorithm to bring the power line equations to the form of two-wire line equations. To assess the correctness of the mathematical model the research was carried out on the physical model of the line. Using the mathematical model there were given the findings of distributed parameters circuits various modes. The proposed method of mathematical modeling of different shape signals transmission to the distributed parameters line adequately reflects the phenomena occurring in the line and can be used for the analysis of electromagnetic processes both in the overhead system and power lines.

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.

The article sets forth the procedure for preparation of energy saving programmes for the system of traction electric supply. List of key measures aimed at reduction of losses of electric power in traction network and equipment of traction substations, and also on increase of carrying capacity of railway sections. Presents the results of studies evaluating the potential of energy efficiency of the system of traction electric supply of Railways.

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 article describes the current state of railway non-traction electric power supply system in the electric grid complex. The main drawbacks of the existing electricity metering system in 0.4-10 kV distribution networks are shown. The main directions of non-tractive electric grid complex innovative development are considered, including directed to increase the efficiency of electric energy transformation, transmission and consumption processes due to the management of distribution networks operating modes. The basic principles of "Digital district power supply" constructing are given.

Global investment projects of JSC "Russian Railways" to increase turnover suggest an increase in the load on the existing areas of electrified railways, in connection with what is urgent problem of passing the required number of pairs of trains at railway stations. Electricity consumption in railways AC characterized by a rather high consumption of reactive power due to the specifics of electric rolling alternating current, which leads to increased levels of stress and loss of power and, consequently, reduce the energy efficiency and the potential capacity and carrying capacity of the railways. One of the least capital-intensive, and in some cases the only possible rational way to strengthen the system of traction power supply AC is the use of transverse devices for reactive power compensation. The article describes the method of determining the power and choice of accommodations in the area of ​​the railway regulated and unregulated devices transverse reactive power compensation systems, traction power supply 25 kV and 2 × 25 kV. The calculation of the input impedance of the external inductance and traction power supply, the main options for power supply circuits and sectioning traction network devices and placing transverse compensation of reactive power, check to ensure a minimum level of voltage at the pantograph of electric rolling stock. The results can be used as the design of new railway sections, and in dealing with increasing the capacity of sites in operation.

Various converters are operated at electric railways traction substations whose rectifiers design includes plug-in power rectifiers and pill ones. Such a variety of rectifiers design causes the problem of the power supply reliable operation unavailability both of volumes and of quality information concerning the characteristics and diagnostic parameters of power semiconductors rectifiers. For a possible prediction of the diodes and thyristors proper operation, new instruments as well as simple technologies of the preventive diagnostics, correspondent to the state and industry standards and instructions should be developed. One of the most accurate methods to determine not only the serviceability of rectifiers but also to forecast their wear - life, is the diagnostic method of recurrent peak backward current. This method is the basis for the design of a peak backward current meter which is used on the Western-Siberian railway. Using this device the screening of about thirty thousand rectifiers was carried out which resulted in the sorting of out-of-work rectifiers, predicting long term rectifiers conditions. The statistical analysis of the research allowed to determine the number of measures to improve the reliability of traction substations converters.

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 considers an approach that allows to reduce the asymmetry of consumed currents by traction substations of railways from a three-phase power supply system using a compensating device with an asymmetric structure installed at the substation. Reactive currents of the compensating device allow to redistribute between phases of the traction transformer active and reactive power of asymmetric traction load and to receive symmetric load of three-phase power supply system. The theorem is proposed to determine the conductivities and reactive currents of the branches of a compensating device with an asymmetric structure depending on the traction loads. The article presents the calculated expressions, which can be used to calculate the conductivity and reactive currents of the branches of the compensating device for any traction load of the feeders, in which the equivalent load, including the reactive currents of the branches of the device and the currents of the feeder zones will be symmetrical and active. As an example of the application of the theorem and the proposed expressions, a test problem is presented in which the secondary winding of a traction transformer with asymmetric traction load of feeders is considered, the conductivity of the branches of the device is calculated. With the use of vector diagrams shows the receipt of a symmetrical system of currents of the secondary winding of the traction transformer. Mathematical expressions allowing to realize the necessary law of regulation of reactive currents of the device are given. The necessary ranges control of reactive currents of the compensating device on traction substation on the set probabilistic laws of change of traction loadings are defined. Various options for the practical implementation of a compensating device that will provide the necessary inductive or capacitive current of each branch are considered.

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 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 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..

In the paper the device for reactive power compensation for the electric locomotives based on passive adjustable compensator was described. This configuration of the compensator improve the power factor of the electric locomotive in all operational modes and raise value of the power factor to its maximum possible value. The management of the compensator unit is based on the extremum seeking control autonomous voltage inverter. Mathematical modeling of electric locomotive showed increase the power factor to a value of 0,98.

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.

The article describes the structural scheme, the algorithmic basis, functional composition and some technological characteristics of the hardware and software of information system of operating control parameters of the electric power in the traction power supply network, structural peculiarities of information-measuring complex, the hub characteristics of the data collection substation, type of equipment used in information and computational complex structure of servers for processing and storage, data volumes and characteristics of the necessary communication lines.