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The paper presents a calculation of the magnetic field over the cable with damage. The cable with damage is replaced to equivalent circuit «conductor - shield». The conductor and the shield is considered as two single-wire lines, loaded on the characteristic impedance to avoid reflections. For this equivalent circuit defined sine wave signal change in the conductor and the cable shield. These results indicate that in cable fault location conductor current is significantly changed and shield current reaches the maximum value. The values of the shielding factor is determined at dif-ferent frequencies for the continuous tubular aluminum conductor and steel spiral conductor. The magnetic field is determined on the earth surface over the cable with metal shield having a «con-ductor - shield» damage taking into account the shielding factor. The results show that the module and phase of magnetic field is incremented in the cable fault location, which can be fixed on the earth surface. The results of calculation will improve the methods and hardware for cable fault lo-cation searching.

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.

In this paper we consider an alternative method to solving problems of technical diagnostics of railway wheels, which consists in developing a system for monitoring critical states of near-surface layers of metal, which has the ability to detect incipient defects in the metal structure of the rolling surface of a wheel.