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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.

The article describes a method for controlling electrical loads rail consumers using energy storage. Different types of energy storage devices used in rail transport were considered. Performed the optimization problem formulation, selected criteria and the method for its solution. As an optimization method used the method of Hooke-Jeeves. A method is proposed to determine the optimal parameters and the optimal control law of charging and discharging of the energy storage. The criteria and calculation expressions that can be used in the design and feasibility study of the effectiveness of implementation of the stationary energy storage for managing schedules loads rail consumers. The mathematical expression was proposed for the energy storage capacity determination. Two criteria were considered in the optimization problem: a minimum active power losses and minimum reduced costs, and a comparison of results. The form factor used to evaluate the changes in electrical loads. Control of reactive power in the AC mains can realize using semiconductor converters and an energy storage. As a variant the electrochemical cells (lithium-titanate batteries) could be used as energy storage for rail electric consumers. As a result, optimal control of electrical loads allows to get technical and economic effects.

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 article analyzes the results of the assessment operating time and power consumption of compressor equipment service locomotive depo Moscow West-Siberian Railway. The algorithms for data preparation for modeling and evaluating the efficiency of the production process are presented. The main factors influencing the power consumption of the compressor equipment are determined and the results of the assessment of their influence are presented. On the basis of the dependences obtained, a mathematical model of the process of power consumption of compressor equipment using fuzzy neural networks and its accuracy is determined. The interface of the developed program complex is presented at an estimation of influence of factors on process of power consumption of the equipment service locomotive depo Moscow West-Siberian Railway.

The article presents the equivalent circuit of three conductors, taking into account their mutual influence. The equivalent circuit contains the resistance and inductance of each conductor, the conductivity and the capacitance of their insulation relative to the earth, as well as the mutual inductances, conductivities and capacitances of the insulation between the conductors. The mathematical foundations of calculating the distribution of electrical quantities in the system of three conductors are considered, taking into account their mutual influence. An iterative incremental model of the software life cycle was chosen as the basis for automating this calculation, taking into account existing approaches to software development. Specific features of specialized software are specified. A structural scheme of the software complex and a block diagram of the calculation algorithm are proposed. The algorithm is based on the iterative calculation of currents and voltages for three conductors, taking into account their mutual influence. In accordance with the chosen model of the life cycle of the software, three versions of software with different functionality have been developed. This allowed us to effectively organize the processes of testing, debugging and implementation. As a result, the software complex has a window interface containing four tabs and allowing to enter the initial data for the calculation, display the results in the form of graphs and tables. For saving the results of calculations, a connection with the database has been implemented.

Efficient use of railway rolling stock is an important aspect of the transportation industry. The presence of wagons on access roads plays a significant role in the overall performance of logistics chains. The article discusses the main approaches to rationing the time spent by wagons, analyzes existing problems and suggests optimization techniques based on modern technological solutions. The purpose of this work is to develop a methodology for rationing the time spent by wagons on access roads, aimed at reducing downtime and increasing the speed of cargo turnover without compromising the quality of cargo handling. The research method includes an analysis of the current state of operation of access roads, identification of the main problems and limitations, as well as the application of the principles of queuing theory. The technological and interoperable components of the time spent by wagons on access roads, including unproductive downtime, are considered. Special attention is paid to the complexity of applying the analytical method due to the difficulties of classifying access roads, the need for accurate data collection and the approximation of the formulas used. The scope of the results includes planning and optimizing the operation of access roads of industrial enterprises, terminals and warehouse complexes integrated into multimodal supply chains. The proposed methodology makes it possible to take into account the specifics of technological operations, the technical characteristics of rolling stock and infrastructural constraints. The practical significance of the work lies in the possibility of reducing the downtime of wagons, improving the use of rolling stock and increasing the overall efficiency of the transport system. The implementation of the proposed approaches contributes to the adaptation of access roads to changes in external and internal conditions, as well as the integration of advanced technologies into logistics process management.

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 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.

The paper is devoted to the calculation of the electrical quantities distribution in the system of three conductors. The first conductor is located on the surface of a uniform soil and the other two conductors are located at depths of h and h . As result, analytic expressions of current, potential and leakage current density in the first underground construction with considering the influence of the second construction was obtained. The influence of second construction increases the value of electrical quantities in the underground construction. The analytic expressions were obtained using Fourier transform method. The analysis showed the influence of the leakage current and insulation resistance of the second construction on the electric quantities distribution in the first construction

This paper examines the feasibility of locating rolling stock on a track section based on the track line's input impedance, taking into account the influence of its hardware parameters and external factors. The aim of the paper is to evaluate the feasibility of using the track section's complex input impedance to pinpoint rolling stock locations in conventional track circuits. The article presents the results of modeling changes in the track section's input impedance using a 25 Hz code track circuit, traditionally used on railways in the Russian Federation and the CIS. Three basic track circuit calculation modes were used as input data: normal, shunt, and control. Using the analytical expressions of classical track circuit theory for these modes and the Smath Studio software package, graphs were obtained of the active and reactive components of the complex input impedance versus insulation resistance, the ordinate of the rolling stock's location, and the location of the rail break. The simulation results demonstrated that it is possible to use the complex input impedance of a track section to determine the location of rolling stock with an accuracy of 50 meters and pinpoint the location of a rail break with an accuracy of 100 meters. These results can be used in the development of rolling stock tracking systems, including high-speed vehicles, as well as in diagnostic systems for rail network components, which will ultimately enable the transition to predictive failure detection systems.

This paper describes an algorithm evaluating the effectiveness of energy-saving devices and technologies, based on the methods of mathematical statistics. Diagram presented in the article. It can be applied in the traction system and power supply without traction. Approbation of the algorithm is executed in the traction power supply system. The developed algorithm includes five stages: 1. Stage calculate the required number of observations. The basis of this stage is to evaluate the dispersion and calculating on it the desired number of observations. 2. Stage of the collection and processing of data obtained before the implementation of energy-saving devices and technologies. Collection is carried out on of electricity consumption and factors influencing the process of electricity consumption. Processing includes the calculation of the correlation matrix, the coefficients of determination and the parameters of the regression equation. 3. Stage of the collection and processing of data obtained after the implementation of energy-saving devices and technologies. Data collection is carried out according to the parameters selected in step 2 and the processing is done by the calculation of the parameters of the regression equation. 4. Stage of comparing the data before and after the introduction of energy saving devices and technologies. Comparison of the data obtained before and after the introduction of energy saving devices and technologies produced using the Chow test and nonparametric mathematical statistics such as omega-square (Lehmann-Rosenblatt). 5. Stage of calculating electric power saving. The calculation is made on the consumption of electricity obtained by the regression equation before the introduction of energy-saving devices or technology by substituting the values of the factor after implementation and actual consumption of electricity after the introduction of energy-saving devices or technology. Approbation of the algorithm was successful.

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 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.

Single-phase transformer with an additional tap at the middle point of the secondary winding is a very common element in the various electrical circuits, including on-board electric rolling stock. A typical case is powered from the transformer zero full-wave rectification circuit. The aim of the article is to provide a detailed description of the computer model developed by the author of said transformer, built on the basis of a combination of circuit and operational design principles. The proposed model can also be used to describe the process in a single-phase two-winding transformer without additional tap, given the possible connection group I / I-6 or I / I-0. Connection groups can be considered individually for each half of the secondary winding in case of using of additional tap. Shows an example of embedding the transformer model in a more complex computer model of the electric traction DC motors excitation current stabilization system, which includes a computer model of a saturable reactor, thyristor rectifier, system of pulse-phase rectifier control and control loop with a proportional-integral current regulator and boost nonlinearity. Obtained during the simulation graphics excitation current in the field winding of collector traction motor and its reactive component show that the above system of stabilization of the current and its computer model of functional and successfully fulfill their functions: at the downturn of the armature current excitation current is maintained by the growth of the current make-up of excitation control rectifier. The correct operation and ease of use of the developed computer model of a single-phase transformer with an additional tap at the middle point of the secondary winding is stated.

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 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.

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 is about defining corrosion state of overhead structures underground part. Specially designed concrete models are used for experiments and calculations. These models are made with the fabric technology of overhead structures creation. «Steel - Concrete» interface region parameters are calculated with a help of transient process which situated when DC power supply is connected to the scheme. There is a formulas and a methodic for calculation needed parameters. In the end of the article theoretical curve is located. It exactly coincides with an experimental curve.

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 article proposes a method for increasing the efficiency of power supply systems for non-tangible consumers due to quadratic accumulation of electric energy on reactive elements in the frequency-beating mode. The proof of the energy efficiency of the beating regime in comparison with the full resonance regime with respect to the implementation of quasiresonance pulsed power supplies is given. The article also deals with the choice of the optimal beat frequency by the criterion of the maximum ratio of the accumulated energy on the reactive elements of the circuit to the one expended from the primary source.

Incorporating passenger perspectives on the quality of ground public transport is paramount for enhancing urban mobility. This study champions the idea of making service quality perception the linchpin of urban transport policy formulation, thereby underscoring a user-centric methodology for cultivating sustainable transportation habits. By integrating passenger feedback, cities can effectively bolster user loyalty and entice new riders to embrace public transport. The research based on the importance of evaluating quality indicators within multimodal systems, which is essential for deciphering the spectrum of passenger sentiments. For urban transport to truly cater to citizen expectations, it is imperative to harmonize city authority ambitions, operator capabilities, and public desires, thereby creating sustainable urban ecosystems. At the heart of this approach lies a holistic planning system that encompasses operator-provided quality, regulator-set target quality, perceived quality, and desired quality. The study places emphasis on formalized assessment processes, acknowledging that passengers make rational choices, gravitating towards the most advantageous travel options. Integrating perceived quality indicators is invaluable for fostering informed management decision-making, which benefits both city administrations in strategic planning and transport companies in route and service optimization. Therefore, a comprehensive, user-centered quality assessment mechanism is pivotal for enhancing efficiency and satisfaction in urban transport, ultimately fostering a more sustainable and user-friendly urban environment.

The article presents a criterion for choosing the optimal type of wavelet function for digital processing of current and voltage values in the analysis of the electric network mode. The increase in the share of electric receivers that distort the quality of electricity sets the task for researchers to use more advanced mathematical tools for analyzing and modeling such power supply systems. The discrete wavelet transform allows the harmonic analysis of currents and voltages under non-stationary non-sinusoidal modes. One of the key tasks in the development of digital technologies in the electric power industry is the creation and development of intelligent electric networks with the introduction of new algorithms for digital data processing and decision making. In this case, algorithms for compression and remote recovery of data on the consumption and production of electrical energy in the cloud should be developed. The wavelet transform eliminates the negative spreading effect characteristic of the Fourier transform in the analysis of non-sinusoidal non-stationary modes. Based on the Parseval equality, the wavelet transform makes it possible to determine the spectrum energy of individual frequency ranges determined by the depth of decomposition and the sampling frequency of the signal under study. The calculation of the energy of the spectrum of wavelet coefficients allows the compression of the flow volume of instantaneous values of voltages and currents. The article presents the results of continuous and discrete wavelet current conversion when switching a battery of static capacitors. Information compression ratio exceeded 5.3. The wavelet transform was performed using eight different wavelet functions. The criterion for choosing the optimal mother wavelet determines the condition of the maximum energy of the spectrum and the minimum standard deviation when restoring the original signal.