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The article presents results ofmodeling andfull-scaletesting of the devicefor remotediagnosisinsulatorscatenaryrailway transport. The maincauses ofbreakdownof insulators. Presents statistics offailurecatenaryinsulators. The plotof the contactnetwork is presentedin the form ofthe line modelwith distributed parameters. To create a virtual model of the device and the line was selected program Multisim 12.0. Described bya block diagramof the devicefor remote monitoringcatenaryinsulators. Shows theprinciple of operationof the deviceto control thecatenaryinsulators. Present a schemeof the experimentat the siteof contact networkOSTUlandfill. Parameters are calculatedareaof contact network. Chosenform ofdiagnosingpulsesto determine thepossible location ofthe faultyinsulator.

In connection with the negative effects caused by the fault of the insulators used in an overhead power transmission line of 6 - 10 kV, it is suggested controlling a condition of a post insulator by the device that responses when breakdown current goes through an insulator. The work of the device for identification of insulators defects is described. Equivalent circuits of an alarm device connection with an insulator in an overhead power transmission line are given. The basic processes, that occur in a system of a supporting insulator of an overhead power transmission line in a serviceable condition and if there is a defect in view of geometric capacitance, absorption current, steady leakage current and surface current of breakdown, are considered.

The article considers one of the ways of improving the energy efficiency of AC electrical system railways 25 kV, 50 Hz. The proposed approach allows to determine the optimal location and capacity of an unregulated device for compensation reactive power according to the criterion of minimum active power losses in a traction electrical system. Modeling of trains on the site was made using instant schemes. Description of the traction power supply system implemented by the node potential method and Steinmetz’s symbolic method. Optimal value of reactive power for all possible locations of a compensating device was calculated numerically by an optimization method of Hooke-Jeeves according to the criterion of minimum active power losses in the traction network. The mathematical model allows to consider the elements of the traction network, schedules of trains, change of traction loads of electric locomotives, schemes of overhead network. The proposed approach was considered on the example test problem, which solution allowed to determinate the optimal location and required value of reactive power of an technical device. The placement of a compensating device in a certain place will allows to minimize the power loss in the contact network, track circuit and traction transformers from the flow of the reactive component of the current in average for all instant schemes with various traction loads. An unregulated technical device for compensating reactive power which is located between two traction substations reduces energy consumption for traction of trains on the 1 - 2 %.

The article considers one of the ways of improving the energy efficiency of three-phase power supply system of industrial and railway enterprises. Presented and proved a theorem, which allows to determine the necessary conductivity and the reactive branch currents compensating device with asymmetric structure, for which the equivalent conductivity of these elements and the load will be symmetrical and active. In three-phase electric circuit of an alternating sinusoidal current reactive elements allow to redistribute active and reactive power between the phases. The use of a compensating device with asymmetric structure will reduce losses from the occurrence of reactive currents, reverse currents and zero sequence in low-voltage three-phase power system. As an example of the use of the theorem and the calculated expressions for determination of conductance of the branches of the asymmetric compensating devices a special test problem was considered. It shows the values of power losses, the coefficients of voltage unbalance with and without using the device. Considered possible options for the practical implementation of such technical devices.

In this article, the technical condition monitoring of power supply line for devices of railway automatics is considered. The algorithm of determining location of the break with using the mathematical apparatus of discrete Fourier transform is proposed.

Article is devoted to production and occupational exposure to «biological factor» for workers оf railway transport. Purpose - improving the system of occupational safety in railway transport under the influence of workers pathogenic organisms. To identify gaps in the system of assessment «biological factor» has been studied Russian normative documentation for a special assessment of working conditions and carried out long-term work on hygienic assessment of working conditions. The article defines the term «biological factor», justify the need for of risk assessment of the harmful factor, expand the list of sources and professional group of railway workers potentially exposed to «biological factor». In this article presents a device for protection and prophylaxis railway workers from biological factor. The principle of operation of the device is based on the integrated use of methods of ultrasonic treatment and ionization to disinfect the indoor air of railway stations, bus stations, subway stations. According to the results of studying the Russian regulatory documentation in the transportation of dangerous goods by railway, identified the main problems and their solutions, in terms of biological safety: formulated the term «biologically dangerous goods»; the necessity of creating a class or sub-class «biologically dangerous goods» and its implementation in the existing rules; developed a simple list of «biologically dangerous goods»; the possibility of the impact of these goods on railway workers.