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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.

The use of twelve-pulse rectifiers instead of six-pulse rectifiers leads to increased efficiency and efficiency of traction substations of the underground. On the basis of experimental research and analysis of circuit solutions, the conclusion is made about the advantage of a twelve-pulse rectifier circuit of a serial type over parallel-type circuits. The use of rectifiers with a parallel type circuit is possible only if there is an equalization reactor, without which technical and economic indicators are reduced. The introduction of the most rational twelve-pulse bridge rectifier schemes of the sequential type can be carried out by upgrading the installed equipment, or by industrial development by manufacturers of dry transformers with different typical power and rectifiers with tablet avalanche valves with coolers based on heat pipes.

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.

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 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 existing protection does not provide protective potential of traction substation grounding grid for the entire period of operation. This disadvantage is removed by improving of automatic drainage unit. The basis of the automatic drainage system is automatic control of drainage current by changing the pulse width of current. This method of current control allows the defined potential remain at the set value. The article presents a functional diagram describing the basic units of the improved automatic drainage unit. The results of the automatic drainage unit tests illustrate that the automatic drainage unit limits the current flowing through the grounding grid to the traction substation, allowing the potential remain at the set value Improved automatic drainage unit has great advantages in relation to existing and operated drain units at this moment and it can be recommended for introduction to the electrification infrastructure of the railway industry. Also this automatic drainage unit can be used for protection of other metal underground structures such as pipelines and other metal structures influenced by stray currents.

This article presents the results of changes calculations in the energy efficiency indicators of the Moscow Central Ring, such as the specific consumption of electricity released for traction by trains of traction substation meters, specific recovery, technical losses of electricity in the traction power supply system when it is transferred to electric rolling stock, including technical recuperation energy loss, depending on various installation options of rectifier-inverter converters in traction substations part.

The results of measuring the components of electromagnetic interference on DC traction substations and AC.

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.

The purpose of the article is to consider the issue of calculating and selecting the settings for the operation of the short-circuit switch KZKS-3.3 when organizing the protection of a direct current contact network in emergency mode. The shorting circuit is measured by the voltage module. When the triggering conditions are met, it is the voltage module that collects the circuit to turn on the switching device of the short circuit. The important question is to choose the optimal installation location of the short-circuit switches and the voltage trip settings. The initial information necessary for the calculation of the settings is determined. The calculation procedure and equivalent circuits for the most common power supply circuits and sectioning of the contact network are given. For current protection of high-speed circuit-breaker feeders, contact formulas are given for determining the sensitivity zones. To select the optimal installation location of the short-circuit and select the voltage pick-up setting from the allowable range, a potential diagram of the contact network section is constructed. The analysis based on the potential diagram allows us to conclude that the organization of protection of the contact network in emergency mode using short circuits is effective.

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 a method of the additional resistance calculating of ground grid drainage unit. This work has two main objectives: development of algorithm for determining the optimal values of additional resistance and to study the possibility of reducing losses in reverse traction network through drainage unit of traction substation. The calculation is carried out with a view to ensuring the normative values of the protective potential on the grounding grid and minimize losses in the reverse traction network. The method is based on the application of the reciprocity theorem, which allows to change the direction of the currents from the source to the load on the reverse one if the system is linear. The calculation of the values of additional resistance and power loss in the reverse traction network for average current on the considered traction substation of the Western-Siberian railway. In results the selection method of optimal values for the additional resistance is offered. This method can be used for designing of traction substation grounding grid protection.

Corrosion processes at various constructive changes of grounding system of traction substation are considered: construction of new cable lines, expansion of the territory of substation, etc. Calculation of corrosion processes of the grounding system consisting of three electrodes is carried out: steel in concrete, the metal gauze in soil, a steel vertical electrode in soil. Results of calculations are presented, the analysis of corrosion processes is made under various conditions.

The mathematical method of calculation of currents of corrosion of two models of grounding models - ekvipotentsialny and nonkvipotentsialny is presented. Soil and electric corrosion of both models is considered. The mathematical method of calculation of sizes of corrosion currents and potentials will allow to estimate a corrosion condition of elements of grounding system of traction substation.

The article deals with the introduction of a twenty - four pulse rectifiers with various rectification circuits on direct current traction substations. The results of the operation of a twenty-four-pulse rectifier installed at one of the traction substations prove the expediency of using such a converter. The variants of the existing equipment modernization, which is a part of the six- and twelve-pulse rectifiers in order to use it in the creation of twenty-four-pulse rectifiers, as well as the requirements for the creation of such rectifiers in industrial design are given.