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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.

The paper considers the use of simulation modeling in the reengineering of technological processes for repairing rolling stock units on the example of repairing a bogie model 18-578 of an open-top car. The most time-consuming sub-process of repairing the bolster of this bogie was considered as the object of reengineering. Three options for reengineering of this subprocess were considered, implying a complete replacement of the technological equipment currently in use at repair operations (positions) with more efficient positions of the subprocess. To substantiate the choice of the most preferable reengineering option, the values of such indicators of the functioning of the subprocess under consideration as its productivity per shift (throughput), the load factor of the resources used at the repair positions, the volume of work in progress at the end of the shift, the number of workers employed in production and the costs associated with the possible purchase of new technological equipment. Simulation modeling of the functioning of the considered sub-process of bogie bolster repair was carried out on the basis of the methods of the queuing theory. The construction of simulation models and their assessment of the above indicators were carried out in the Arena RockWell Software environment. When developing simulation models for each of the possible options for reengineering a subprocess, the discipline of its organization and maintenance was taken into account. In the article, for each of the reengineering options, the calculated quantitative estimates of the listed indicators are presented, obtained using the corresponding developed simulation models. The use of these assessments reduces the risks in the development and subsequent implementation of organizational and technical solutions associated with the modernization of the considered technological sub-process of repair of the bolster of a gondola car bogie.

Microminiaturization elements of communication systems contributed to development Internet of Things, which led the expansion of various railway transport services. One of the Internet of Things component`s is the wireless sensor network (WSN). Feature of WSN is a dynamically changing spatial and information network environment. It complicates the adoption of promptly reliable management decisions based on assessments of the states of network elements. One of the directions of making a reliable decision in a complex network environment on the WSN is using cognitive maps in the WSN control nodes. In this article discusses various models of cognitive maps for assessing the states of network elements and network processes, which can also be used for railway transport services.

Station radio communication is an integral part of the technical means involved in the organization of a safe transportation process. Increasing the signal power in places with a complex electromagnetic environment remains an urgent issue. A passive repeater can serve as a solution to this issue, therefore the purpose of this work is to test the possibility of increasing the signal power level using a passive repeater.The article provides an analysis of a passive repeater used as a device that improves the quality of radio communications in places with a difficult electromagnetic environment. The differences between the use of a passive repeater and active relay stations are given.An analysis of the existing methods for calculating the parameters of passive repeaters was carried out, on their basis, modeling and calculation of the parameters of a passive repeater were carried out for the development and conduct of research in real conditions at a railway station. The design, materials of manufacture of the passive repeater, as well as the measurement scheme in real conditions are presented.The study is based on theoretical calculations and performance checks in real conditions and comparison of the results obtained. As a result of the study, it was found that the use of a passive repeater in a complex electromagnetic environment makes it possible to increase the signal power level, thereby increasing the stability of radio communication.It was noted that it is necessary to refine the existing method for calculating a passive repeater, since the above technique was used when calculating passive repeaters over long distances. A variant of fastening passive repeaters without the development and installation of additional new structures is proposed, the need to organize further protection against overvoltage is indicated.The results obtained will be useful in the development of new radio relay communication lines and the modernization of existing ones for places with a difficult electromagnetic environment and rough terrain.

The influence of systematic failures to the functional safety of automated control systems of hazardous technological processes is considered. It is shown that stability ensuring of the process control system to systematic failures is an actual task for today. Approaches to increase the robustness to systematic failures recommended by IEC 61508 are presented. Special attention is paid to methods based on diversion. The functional diversity and technology diversity have been revealed in detail. Examples of using diversification in railway automation systems are given. The main problems of using diversification to increase resistance to systematic failures are formulated. The main advantages of using diversification are increased resistance to systematic failures and reduced risk of dangerous failures through the usage of diversified protection methods at the functional levels of the APCS. The disadvantages of using diversification are a significant increase in the costs of developing and automated process control system maintenance, the difficulty of confirming the different behavior of diversified channels in case of systematic failures, and the lack of an effective method to assessing the sufficiency of the obtained diversification for a given level of safety integrity.