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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.

The results of mathematical modeling of the optimization of maintenance cable lines are presented in article. The results can be used to calculate the optimal frequency and number of major repairs and substitutions of cable lines.

Using the example of operating gas fields in the Western Siberia, the issue of the correct choice of voltage class, considering all the periods of gas fields life cycle, appears. Wrong choice of the voltage class leads to braking development of a gas field. Gas field technological scheme during the each period of the life cycle is considered, the dynamics of the electrical load is estimated. The analysis of existing methods of choosing the voltage class is carried out and their flaws are revealed. Mathematical models of the optimal voltage class calculation and discounted costs calculation are developed using the theory of experiment planning. An algorithm of choosing the optimal voltage is developed and the distribution and supply networks of the external power supply system of the existing gas fields in Western Siberia are investigated. Progressive voltage class for power supply and distribution network is proposed. Conclusions are made.

In article the algorithm of operation of the existing regime automatic equipment of transforming aggregates is considered. Earlier it was read that use of automatic equipment of switching on switch-off of reserve transforming aggregates is an effective remedy of lowering of losses in case of regulation of power of substation depending on tractive loading. Defining factors of assessment of efficiency of automatic equipment are the current and temporal settings, and also restriction of number of switchings in days. The analysis of diagrams of tractive loading showed that there is rather large number of temporal intervals where operation of automatic equipment is ineffective. On the one hand it is connected to the fact that loading is above a point of equality of losses in case of one and two transforming aggregates quite short time, and automatic equipment connects the reserve transforming aggregate already in the course of lowering of loading and disconnects it after a temporal setting. On the other hand - operating restriction of number of switchings of the reserve transforming aggregate in days doesn't allow to gain the considerable economic effect. The decision on use of regime automatic equipment with the existing settings can be the positive if at the same time the estimated effect in the form of abbreviation of losses of the electric power is above cumulative damage from switching of the reserve transforming aggregate. Regime automatic equipment in most cases, it is necessary to consider not as means of obtaining economic effect, and as means of reliability augmentation of operation of semiconductor rectifiers at the peak moments of loading what in turn influences reliability of electrical power supply of pull of trains in general.

In the article, on the basis of the thermodynamic analysis of the working process in the turbine, a method is presented for determining the generation of electricity based on heat consumption and an assumption is made about the possibility of instrumental measurement of the amount of generation and the implementation of accounting in real operating conditions of the steam turbine. This indicator can become an important indicator in the district heating system and automatic regulation of heat energy supply, such a statement of the problem in the district heating system was made for the first time and requires additional research. The article discusses the influence of electricity generation on thermal consumption on the efficiency of the power system of district heating. Dependences of electricity generation based on heat consumption on the share of steam supplied to the heating extraction are obtained. Specific power generation has been determined taking into account regeneration.

The issue of designing devices with optimal characteristics of converting an electrical signal and its shape without distortion is relevant when developing a device with small dimensions for electric rolling stock. In this article, the influence of transformer parameters on the form of voltage transmission is considered and recommendations are given on the choice of values of these parameters. This applies to pulse, differential, and low-power transformers. The study of this issue is moving from theory to constructive calculation. In the era of digital twin design, the computational mathematical model of the transformer will allow for a quick decision on compliance with the inherent requirements for the product. Being universal, the proposed model allows performing calculations for any pulse transformer, provided that the appropriate initial data is specified and will allow obtaining an estimated characteristic of the transformer already at the design stage. The study showed the relationship between the transformer design, the materials used for the magnetic circuit and the shape of the output signal. Obviously, the dissipation inductance and the capacitance of the windings are the main parameters that introduce distortion into the signal. Modeling of the winding design and the selection of magnetic alloys or ferrites help to reduce eddy currents in the magnetic circuit, which improves the characteristics of the output signal and reduces the effect of the constant component of the current at the end of the pulse. A transformer model with reduced core dimensions made of steel with a smaller rolled thickness and a homogeneous domain structure, as well as the use of a distributed winding along the core, which has a minimum intrinsic capacitance, had the least effect on the output signal with an acceptable signal distortion of 3 %. The resulting transformer model can be used to create a finished product.

The growth of production capacity requires a constant increase in fuel consumption, which leads to an inevitable decrease in fossil fuels, whose reserves are limited. As a result, it is necessary to gradually switch to the use of secondary energy resources, in particular, the use of secondary gases generated as a result of production processes. This article discusses the use of natural gas conversion by adding it to a high-temperature converter gas stream in order to reduce its temperature to reduce the thermal load on the heating surface and further use as the main fuel in power units. Using the Ansys Fluent universal software package, a computational model of a natural fuel converter gas pipeline was developed, and the distribution contours of the composition and temperature of the fuel mixture formed by the chemical interaction of gases were obtained. The analysis of the obtained fuel mixture was carried out, and the efficiency of the obtained synthesis gas was compared with the initial fuel. It was shown that as a result of a chemical reaction, the resulting gas has an increase in thermal efficiency by 64 %. The results of this study demonstrate the possibility of further application of the resulting fuel mixture as the main fuel for technological processes.

The paper deals with the problem of the presence of thermal inertia in thermoelectric converters of general industrial design, used to measure temperature in most technological installations with an ambient temperature above 200 ° C. The aim of the study is to develop an algorithm for predicting the temperature of the environment with known thermal characteristics of the temperature sensor and to implement the algorithm directly in a general industrial programmable logic controller (PLC). As the main method, the work uses the method of mathematical modeling and description of the object in transfer functions and in the form of differential equations. The work uses a previously developed engineering technique for determining the thermal inertia time of industrial sensors, based on a single disturbance and an assessment of the dynamic characteristics of an object. On the basis of the research and mathematical modeling, algorithms for predicting the temperature of the medium by the parameters of the thermal inertia of the temperature sensor and the rate of change of the thermocouple signal have been developed and implemented. The implementation of the algorithms in the TIA Portal environment based on the Siemens Simatic S7-300 PLC using the PID Control library is proposed.

In article the technological actions for suppression of formation of harmful emissions from power objects using organic fuel are described - natural gas, coal and fuel oil. The methods of purification of combustion gases of the main pollutants are offered. Devices of cleaning of large volume of combustion gases of the increased concentration of ashes, and technology of combustion of fuel are presented.

The problem of optimizing train driving modes continues to be relevant for a long time, despite a large number of scientific research and development in this subject area. This is due both to the general complexity of the implementation of the technological process of running the train, and to parametric uncertainty and significant variations in the parameters of the control object itself and the external environment. Well-known methods for calculating energy-optimal train driving modes (calculus of variations, the maximum principle, dynamic programming) and auto-driving systems based on them assume some simplifications of the original problem, and, as a result, implement quasi-optimal control in practice. In this regard, the development of methods for searching for the global extremum of a functional defined on the set of permissible trajectories of a train as a dynamic system is both theoretically and practically a significant task. The aim of the work is to create a computationally efficient metaheuristic algorithm for searching for energy-optimal control as a global extremum of the objective function, the values of which are calculated using a reference model of the control object. The authors have developed a problem-oriented evolutionary algorithm for calculating the optimal control of train movement based on the theory of random search. Its features are the proposed specialized operators of local random search, taking into account the specifics of the control object as a multi-mode system; combined procedures of local and global optimization based on the concept of a multi-island population algorithm with superpopulation, as well as a method of selection (selection) of promising options based on the clustering algorithm. Computational experiments have shown good convergence of the algorithm and repeatability of the calculation results. Based on the solutions obtained, a train running time controller can be implemented that implements asymptotically optimal control.

The article examines the technique of designing diagnostic system of infrastructure of electrical railways based on use of bayesian networks for prediction of probabilities of failures. To achieve maximum effectiveness of diagnosis we should minimize the number of input parameters, while maintaining the required accuracy. It is proposed to create a mathematical model of the diagnostic system, that will allow to evaluate the influence of each parameter on the accuracy of prediction of failures. To compensate the lack of source data we can use the advantage of bayesian networks - the opportunity to generate network structure by the method of expert evaluations. Generated bayesian network will perform the failure probability calculation with limited information.

Currently, according to regulatory documents, the resistivity of power line wires is assumed to be the same for any permissible load current and the heating temperature of the wires is equal to 20 degrees. This account of resistivity causes significant errors that significantly affect the operating modes of power transmission lines. This article analyzes the influence of outdoor air temperature, load current, solar radiation intensity, wind speed and direction on the heating temperature of overhead power lines, and as a result, on the value of the resistivity of the wires and power and electricity losses in them. The example of the BAM highway shows that even in the conditions of one region, the outdoor air temperature varies, depending on the time of year, within a very wide range. This in turn requires careful consideration of the dependence of the resistivity value of the line wires on the external air temperature. At the same time, it is shown that it is permissible to ignore the intensity of solar radiation, wind speed and direction on the heating temperature of overhead power lines due to the lack of comprehensive information about these factors and their opposite direction. However, this assumption will only be valid for operating currents in the range from zero to double the current value corresponding to the economic density. When calculating power losses, especially in heavily loaded lines, it is necessary to take into account all external temperature influences. Due to the appearance of sensor temperature sensors, it is proposed to use them directly to measure the heating temperature of line wires and then calculate their resistivity.

This article discusses a modern method for diagnosing track circuits using broadband signals. The relevance of this research stems from significant shortcomings of traditional track circuits, such as low information content, strong dependence on ballast condition, and high operating costs, which lead to significant economic losses and risks to traffic safety. The proposed approach using broadband signals enables continuous monitoring of track conditions in real time, precisely localizing defects such as breaks, current leaks, insulation deterioration, and microcracks, which is impossible using traditional methods. This not only improves traffic safety but also significantly reduces the number of false alarms. The paper presents a detailed mathematical model of broadband signal propagation, taking into account key attenuation factors: the effect of current leakage through ballast, sleepers, and track connections. A comprehensive analysis of the signal's frequency characteristics was conducted, including a study of the skin effect in rails and the dependence of the complex ballast impedance on external conditions such as humidity and temperature. To minimize signal loss, a comprehensive approach based on adaptive frequency range optimization and data processing algorithms was proposed. The study focuses on the principle of matched filtering, which maximizes the signal-to-noise ratio at the filter output through effective signal compression and intelligent parameter selection. A structural diagram of the diagnostic system with a detailed description of its functional components was developed and presented. The study results demonstrate that the implementation of a monitoring system based on broadband signals enables continuous monitoring of infrastructure conditions without interrupting service, significantly improving the accuracy and speed of defect localization. Practical implementation of the developed method can significantly reduce operating costs and improve the overall reliability, safety, and throughput of rail transport.

To improve the accuracy of the diagnosis of the technical condition of rolling stock, it is necessary to develop new algorithms for the digital processing of signals coming from sensors at the time of the passage of the axes of wheeled pairs of wagon carts during the uniform movement of the train on the straight section of the railway track. The use of modern mathematical application software packages to model digital-based data processing algorithms reduces the cost and time of developing automated systems to diagnose the technical condition of the rolling stock of railways. To assess the accuracy of the fixation by the magneto-induction sensor of the moment of passage of wheel pairs axly, an asthigmatic model is proposed, allowing to investigate not only the energy properties of the sensor, but also the shape of the output signal, taking into account the real dimensions of its magnetic core. The developed model allows you to classify the pore. The developed model allows to classify the order of astigmatism model magnetoinduction sensor based on a set of discrete virtual sensors

The article deals with the consumption of fuel and energy resources, including a significant proportion of these resources spent on the organization of electric heating (773.7 million kWh). It was noted that until recently in the reporting of JSC « Russian Railways » there were two different approaches in determining the actual volume of electric energy consumed by electric heating equipment, not equipped with individual metering devices based on the calculation-analytical and calculation-statistical methods. It was found that the results of calculations by both methods have a significant deviation between them (up to 100 %). The purpose of the study is to determine a unified approach that allows to accurately record the consumption of electric energy in these conditions. The characteristic features of each of the applied methods were analyzed, comparative studies on a number of objects of four Railways (October, Sverdlovsk, South Ural, East Siberian), characterized by different climatic characteristics were carried out. At the same time, studies were carried out on the applicability in practice for the regulation of fuel and energy resources of the automated system « Stationary energy » . According to the research results, the value of the deviation of the actual consumption of electric energy from the calculated for both applied methods is shown. A method for determining the actual consumption of electric energy for heating on the basis of a preliminary calculation of the allowable volume consumption of thermal energy with subsequent conversion into electrical energy is proposed and confirmed by tests. The results obtained were adopted when updating the « Methods of analysis and planning of electricity consumption for non-traction needs in JSC « Russian Railways » , approved by the order of JSC « Russian Railways » from 22.08.2018 № 1866p in terms of determining the resource requirements for heating. Based on the results, changes were made to the procedure for filling in the data in the corporate management reporting of EO-10U.

The article discusses the issues of improving safety when performing production work near railway tracks, which are associated with a high level of risk for personnel. The purpose of this work is to develop and substantiate a promising system for notifying work crews about the approach of rolling stock, which can increase the effectiveness of safety measures at railway infrastructure facilities. The methodological basis of the study was the analysis of the causes of accidents related to the shortcomings of existing warning systems, as well as modeling the signal generated by an electromagnetic sensor when the wheel crest passes over it. To implement the system, it is proposed to use the LoRaWAN network and LoRa radio modules combined with Arduino microcontrollers. As part of the research, a structural diagram of the system and a working layout have been developed, including transmitting devices with a composition detection sensor and receiving devices integrated into workers' signal vests. As a result, a mathematical model of the signal generated by a change in the magnetic flux caused by the wheel approaching the sensor has been obtained. The dependence of the magnitude of the electromotive force on the position of the wheel relative to the coil is proved. Graphs of the dependence of the magnetic flux and the induced signal on the transit coordinate are constructed. The proposed system can be used as the main or auxiliary means of notification during repair and other work near the tracks. The conclusion is made about the prospects of the development for implementation in the industrial safety system of Russian Railways. The proposed system has high potential efficiency, can function independently and independently of weather conditions, and also serve as a reliable complement to the work of alarm systems. The introduction of this technology can significantly reduce occupational injuries at railway infrastructure facilities.

The article discusses the operation of systems for interval regulation of train traffic based on a digital radio channel in the absence of radio communication. The aim of the study is to determine the maximum allowable time for the absence of radio communication between the radio blocking center and a moving train in the interval control system. Criteria are proposed that allow assessing traffic safety, as well as reducing the throughput of train traffic in interval control of train traffic systems. The results of calculating the maximum permissible time of radio communication absence in interval control of train traffic systems for freight trains are obtained. Taking into account the maximum allowable time for the absence of radio communication will completely eliminate the likelihood of a dangerous convergence of trains and ensure compliance with the allowable speed mode with a minimum interval of freight trains.

The article presents the results of research of a point magneto-induction sensor based on a mathematical model, which allows you to increase the reliability of automated systems for diagnosing technical condition rolling stock in the course of train movement by improvement the accuracy of the initial information, that is, the moments of fixation passing of wheelset axles over magneto-induction sensors. At the first stage of developing a stigmatic mathematical model the analytical dependence of the value of the magnetic flux in the magnetic core and the output EMF value on resistance of the air gap between the sensor and the wheel crest. At the second stage of development of the mathematical model found time dependence of the magnetic resistance of the air gap between the core of the magneto-induction sensor and the comb wheels of a railway car moving along a straight track at a constant speed. On the basis of application the developed stigmatic model allows evaluating the energy parameters of magneto-induction sensors depending on the properties of modern magnetic materials. The simulation results showed that the MMF value is constant the magnet determines the main parameters of magneto-induction sensors, so the use of modern magnets based on rare earth they allow to eliminate the traditional disadvantage of outdated types of magneto-induction sensors, that is, to reduce their size and weight. The application of the proposed stigmatic model expands the scope of possible solutions to extreme problems for selection and justification parameters of magneto-induction sensors, helps to improve the accuracy of systems for diagnosing the technical condition of the car fleet and traffic safety on railway transport.

The article presents the results of measurements of electricity on active and passive sectioning posts the traction power supply system direct current sections of railways with III and IV path profile type. Basic characteristics of operating modes sectioning posts for the purpose of assessing the amount of electricity transferred and duration of work electricity storage in different modes are considered. The most observed voltage values, volumes of transmitted energy and duration of each case are defined. Choice of theoretical distribution laws, allowing to use the experimental values obtained in further calculations in modeling of operating modes electricity storage is completed.

The article deals with the application and use of heat pump installations as a low-potential source of heat energy to provide consumers with heat energy in the building heating system. Today, one of the most environmentally friendly and economical alternative sources of thermal energy is a heat pump unit. The use of these devices will reduce COemissions. The main advantages and disadvantages that appear during the operation of heat pumps are listed. Based on the results of tests of boilers using organic fuels (coal, fuel oil, natural gas)and low-potential heat sources with an electric drive, the dependences of the heat transformation coefficient of the heat pump and the efficiency of boilers operating on organic fuels on the cost of conventional fuel per unit of released energy are constructed. The coefficient of heat transformation of heat pump installations in the range of changes in operating parameters 3,0 < µ < 5,0 is determined. A graph of the dependence of the energy conversion coefficient on the temperature of the heat carrier in the heating system and the ambient temperature is constructed. A schematic diagram of the connection of a heat pump installation to the building heating system is proposed. Studies were conducted in the period from April 1 to April 21, 2021 in the laboratory auditorium of the educational building of OmGUPSa and the readings of the main parameters of the operation of the heat pump unit with the Vitocal 242-S heat pump were recorded. Based on the results of the main parameters, the following are calculated: the thermal load on the room heating system; the temperature of the coolant in the supply pipeline; the amount of electricity consumed by the heat pump; the conversion coefficient of the COР. The optimal values for this heat pump unit under the specified operating modes are estimated.

The calculation of the forecast demand for electric energy by energy systems and complexes of the constituent entities of the Russian Federation is an urgent task. The use of deterministic methods for objects of a similar scale is practically excluded due to the absence or significant incompleteness of the source data. Statistical data available in official sources in an unchanged format is usually presented for a period of 3 - 5 years, which is insufficient for the use of artificial neural networks. The article attempts to study the properties of similar energy systems and complexes. Modern power systems and complexes belong to closed subsystems, the set of elements and connections of which is equivalent to the set of elements of local subsystems of a higher level energy system. This means the inadmissibility of drawing up predictive rules of functioning without taking into account heterogeneous external influences. The system and subsystems are presented as a "black box". Interactions between the system and the external environment and within the system are carried out by the transmission of signals, which are described by a finite set of factors available for analysis and forecasting. The analysis of the possibility of supplementing the general population with statistical data on other objects with a similar structure is carried out. The property of heteromorphism of energy systems and complexes is confirmed. The example of energy systems in the regions of the Russian Federation shows the possibility of a similar approach if non-collinear groups of factors are applied to the analysis. The results of 15 calculations of the most energy-intensive entities of the country are presented, in 28 % of cases the accuracy of forecasted power consumption accuracy is less than 5 %. A further increase in the accuracy of the forecast should develop in the direction of increasing the number of input factors, subject to the condition of the absence of their collinearity and multicollinearity. It is shown that energy systems and complexes of various scales can be described by non-Gaussian stable distributions with infinite dispersion of non-Gaussian distributions, which makes incorrect the use of such methods as the simple extrapolation method, as well as statistical methods based on the assumption that the random distribution law is normal.

The use of new self-supporting insulated wires and high-temperature wires in the operation of power lines allows increasing the capacity of lines and, as a rule, reducing operational costs. An optimal utilization of the power line load capacity depends on the precise determination of the permissible current loads. The values of permissible currents and steady-state temperature are the main parameters of the line operating mode, affecting the strength and sag of the conductor. The temperature of the wire depends on weather conditions and current load. There are methods for determining the temperature and permissible currents for widely used traditional wires such as AC. They are partially outlined in the EIS (Electrical Installation Standard) and the standard of PJSC FGC UES (Federal Grid Company of Unified Energy System) of 2013. However, there is lack of studies in new types of wires. The paper considers the effect of weather conditions and load on the temperature and real-power losses in insulated and high-temperature wire, and solar radiation is under special consideration. For comparison, we present the results of calculations on traditional AC wires. The research shows that solar radiation, being taken into account, provides an increase of real-power losses of about 2 % with the given values of load and weather conditions. Calculations of permissible current values according to the developed technique for classical AC wires reveal a high coincidence with the values from PJSC FGC UES standard. The relative error is within two percent, and the proposed method is more generalized. It allows simultaneous analysis of both uninsulated and insulated wires. Due to the widespread use of self-supporting insulated wires, power industry experts can use the developed software in the design and operation of modern power lines to optimize capacity.

The authors consider the question of the limits of applicability of the capacitor method for measuring the real part of the dielectric constant of printed circuit boards and telecommunications cabled rail transport using the example of FR-4 fiberglass laminate and the cable PK-75-4-12 in the frequency range from 10 Hz to 100 MHz. The measurements were carried out at a constant temperature and humidity of a known material. Comparison of the obtained values with the passport data on the material is carried out; a measurement procedure is developed with overlapping frequency ranges by changing the values of the measuring resistors from larger to smaller with increasing frequency of the input signal. It is shown that in the high-frequency region, the measurement accuracy is directly affected by the parasitic inductance of the capacitor sample under study, as well as the active resistance of the leads and plates and its increase due to the skin effect. The article also discusses the ways of accounting and calculating the parasitic elements of a capacitor. One of these ways is to study the characteristics of the elements of the sample at the first proper serial resonance of the capacitor under study.

This article examines the enhancement of local control and monitoring systems for railway turnouts at stations based on wireless technologies. Instead of the traditional four-wire turnout control scheme, a wireless communication system utilizing a microcontroller and LoRa radio module is proposed. A custom-developed application installed on a tablet authenticates users via login credentials, password, and an NFC card. The application provides functionalities such as viewing the current status of the turnout, switching it to the required position, sending control commands, and recording and archiving operational data. Each command issued is saved both in the tablet’s internal storage (local database) and in a remote server database via the internet. For every command, parameters such as date, username, turnout number, status, and type of operation performed are logged. The newly developed scheme and mobile application enable wireless control of turnouts from the locomotive cabin, creating the possibility of performing shunting operations without the involvement of a shunting operator. The article presents the system’s operating algorithm, user interface, schematic solutions, and key functions of the tablet application. Furthermore, a structural diagram of the wireless turnout control system and a practical model based on an experimental prototype are provided. During the development of the software and hardware solutions, the requirements for ensuring traffic safety based on switch control schemes were thoroughly analyzed and taken into account through the following measures: prior to switching to local control, the section’s occupancy status is automatically verified; the switch position is visually indicated on the tablet; and all commands issued by the user are archived in both local and server databases. Furthermore, the ability to remotely control the switch enables safe operation without the involvement of a maneuvering agent. The proposed approach is considered technically suitable and practice-oriented for implementation in the automation of railway infrastructure.

Nowadays a frequency-controlled externally excited synchronous motor intensively uses in highly automated high-power electric drives. Earlier there were less reliable and more carefully maintained electromechanical direct current systems in these applications. At the same time, setting up of the closed-loop automatic control systems with subordinate regulation of the synchronous machines is the more difficult task. This is because a synchronous machine is a more complex control object. The purpose of this work is a comparative analysis of transients. In this case, saturation is taken into account according to the magnetic flux in the air gap. The coordinates of the machine are regulated by two different automatic control systems. The first system is typical, which uses field-oriented control of the magnetic field of the stator, the second system is upgraded, it selects the law of control of the magnetic field depending on the static load. Special attention in the current article is paid to the method of accounting for the saturation of the magnetic system of the motor and the construction of a mathematical and simulation model convenient. This article substantiates the feasibility of synthesizing more complex automatic control systems are ones with variable structure. The choice of the magnetic field control law in such systems avoids the negative effect of saturation of the machine's magnetic system on the quality of transients. The models presented in the current work can be used in the design of real controlled synchronous electric drives operating under high loads.