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The subjects of the study are the problem of controlling the crew in space by means of an automatic system for controlling the gap between the electromagnet poles and ferro-rails in the system of high-speed land transport based on the levitation effect. One of the main conditions for comfortable levitation mode of the crew is the absence of vertical deformations of the crew during multipoint suspension due to non-uniform distribution of lifting and guiding forces. In order to ensure the stability of the crew's electromagnetic suspension, various combinations of control system feedbacks are proposed. The results of the study of the electromagnetic suspension control system using the electromagnet current feedback in the land speed vehicle levitation mode are presented. The main requirement to the control system of an electromagnetic suspension in the levitation mode is the maximum permissible deviation of the permissible air gap ±5 mm under the action of the impulse of the aerodynamic force in the horizontal plane and the speed of its application. The principle of subordinate regulation of the control system parameters with the use of regulators in accordance with the functional two-loop system of automatic regulation with current feedback has been proposed. The application of the double-loop automatic control system at supply voltage fluctuations corrects the electromagnet current and excludes the deviation of the maximum permissible gap between the electromagnet and the ferro-rail. The performed calculations prove that the introduction of the electromagnet current feedback decreases the velocity transfer coefficients and thus increases the signal speed.

In this article, the authors have studied the electromagnetic processes of an inverter based on thyristors and IGBT transistors of an AC electric train in the regenerative braking mode. To accomplish this task, a method was used to compose instantaneous replacement schemes and systems of differential equations corresponding to a certain time interval of the rectified voltage diagram and the currents of the inverter arms. On the basis of the study were given the disadvantages of thyristor inverter and the advantages of transistor.

The article presents a method for determining the thyristor shoulders of the rectifier-inverter converter (inverter) of an electric locomotive, on which the control pulses are passed. The method is based on the analysis of the duration of the current switching of the thyristors of the inverter shoulders and the rate of rise of the rectified current in the inverter circuit of the electric locomotive. The implementation of the method is carried out by refining the software of the microprocessor control system of the electric locomotive. The simulation of electromagnetic processes of rectifier inverter Converter of AC locomotive series 3es5k "Ermak" in the mode of regenerative braking during emergency operation is carried out on the example of missing control pulses on thyristor shoulders VS2 and VS7. As a result of modeling, data are obtained that confirm the effectiveness of the method proposed by the authors

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

In this article a shielding effectiveness calculation method for the radio electronic equipment is considered. Monolayer and multilayer shields made with aluminum, cuprum, steel is investigated. Interaction of pulse magnetic field and conductive shield is simulated using finite difference time domain method. Frequency and time dependencies for the shield impedances are shown. Also pictures of electromagnetic field distribution near shielding are presented. Time dependencies of electric field on the shield external and internal borders are shown.

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 devoted to the problem of elimination of thermomechanical damage on the surface of rolling wheel pairs of cars, which arising from the use of brake shoes to reduce their speed. A new design of the brake shoe equipped with electromagnets, which provides braking without jamming the wheel pair. Article contains calculation of the braking force and the provide slowdown .

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.