The article proposes a method for determining the optimal location of a self-supporting fiber-optic cable laid along the supports of high-voltage power transmission lines. The methodology is focused on the use of both a manual calculation method and with the use of electronic computing equipment.

Keywords: fiber-optic communication line, electric field, induced voltage potential, electrothermal degradation, optimization of placement of self-supporting fiber-optic cable

The problem of creating semiconductor thermoresistors (PTR) capable of dissipating large amounts of heat is an urgent problem of semiconductor technology. The article presents a brief analysis of the possibilities of using high-power ATGM, the picture of the distribution of thermal fields in the mass of the thermistor under certain boundary and initial conditions. It is shown that when selecting a thermistor material, special attention should be paid to the specific thermal conductivity of the material.

Keywords: High power thermistors, current density, thermal conductivity, energy balance, similarity criteria

The article is devoted to the analysis of emergency situations related to the damage of gas-insulated switches on ultrahigh-voltage lines. The results of mathematical modeling of aperiodic oscillatory process produced in the Simulink system, which occurs when a high-voltage power line containing shunt reactors is switched on under the nominal voltage, are presented. The variants of using a switch with a set of pre-switched resistors in order to minimize the destructive influence of the aperiodic process that occurs when an overvoltage pulse occurs are considered. The results of the simulation of the switching process in the application of high-voltage switches with a set of pre-switched resistors. The simulation was performed on the parameters of the current transmission line with a nominal voltage of 500 kV on the site of the substation "Eletskaya" - nuclear power plant "Donskaya".

Keywords: shunt reactor, aperiodic process, high-voltage power lines

The authors examine the peculiarities of fiber-optic cable electric parameters changes under the influence of a strong homogeneous alternating electromagnetic field. Variants of the process which can be used to describe the influence of the electromagnetic field on the fiber-optic cable are proposed.

Keywords: Fiber optic cable, electrothermal degradation, kevlar, electrical conduction

The authors examine an alternative method of traction station load balance which needn’t capital investments for technical extension. The authors solve the task of loading partial balancing and suggest exploited transformer construction changing.

Keywords: Balancing transformer, the coefficient reverse sequence, regulation voltage under load.