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Possibilities of expansion of settle of typical elementary links of mechanical oscillation systems are considered. As examples of links for transformation of movement the screw and level mechanisms are offered. Introduction of new links is equivalent of elementary links with transfer function of differential of second order. The method for definition of parameters of dynamical absorbtions of oscillation are offered.

The purpose of the article is to consider the issue of calculating and selecting the settings for the operation of the short-circuit switch KZKS-3.3 when organizing the protection of a direct current contact network in emergency mode. The shorting circuit is measured by the voltage module. When the triggering conditions are met, it is the voltage module that collects the circuit to turn on the switching device of the short circuit. The important question is to choose the optimal installation location of the short-circuit switches and the voltage trip settings. The initial information necessary for the calculation of the settings is determined. The calculation procedure and equivalent circuits for the most common power supply circuits and sectioning of the contact network are given. For current protection of high-speed circuit-breaker feeders, contact formulas are given for determining the sensitivity zones. To select the optimal installation location of the short-circuit and select the voltage pick-up setting from the allowable range, a potential diagram of the contact network section is constructed. The analysis based on the potential diagram allows us to conclude that the organization of protection of the contact network in emergency mode using short circuits is effective.

In the Russian Federation, most railway accidents take place at passive level crossings. The majority of scientific papers on the topic of crossings deal with the improvement of active level crossings operation. At present, there is no effective way to improve safety at passive level crossings. The subject of the study is passive level crossings. The aim of the paper is to develop a set of preventive measures to avoid accidents at passive level crossings. The article describes the cases of traffic accidents at level crossings of the West Siberian railway, studies the scheme of passive level crossings and offers a schematic diagram of the accident prevention system at passive level crossings. The work algorithm of the accident prevention system at passive level crossings and the algorithm of giving the locomotive a notification of an emergency situation at passive level crossings are presented. Using the existing coding scheme of the train protection system as a transmission line for information about an emergency situation at a level crossing allows simplifying significantly the scheme of the developed system. The paper also calculates the maximum permissible time of occupation of the crossing by motor vehicles and the time of coding change in the automatic locomotive signaling system of continuous type. The proposed accident prevention system at passive level crossings does not require additional equipment to organize the communication channel and is cost-neutral. Equipping passive level crossings with this system will improve train safety, reduce the number of accidents and increase the efficiency of the railway transport complex in general.

The article considers the issue of providing protection for the contact network when removing 3.3 kV traction substations from the Nazivoye direction of the Omsk power supply distance of the West Siberian Railway. When the 3.3 kV switchgear is brought out to repair, the protection zone for connection of the contact network of adjacent traction power supply system objects (traction substations, sectionalizing stations, parallel connection points) increases. To ensure the protection of the DC contact network, lowered settings for the operation of high-speed circuit breakers are introduced, which inevitably limit the capacity of the section for the passage of freight trains. Considered the existing order of withdrawal of equipment for repair with the inclusion of a traction substation post section. The limitations of skipping freight trains during the implementation of the existing scheme are estimated. Short circuit currents are also calculated and the settings for the protection of high-speed circuit breakers are selected when the sectioning station is switched off and the sectional disconnectors of the station are switched on. It was found that the condition for selecting the protection settings is not fulfilled when detaching from the minimum value of the short-circuit current. To reduce the limitations, a prototype of a short-circuit contactor of a direct current 3.3 kV grid has been developed. The use of a short-circuit-breaker allowed the protection of the contact network, for the time of the withdrawal of the switchgear equipment for repair, without transferring to lower settings for the operation of circuit breakers. Also in the article are given the technical characteristics and features of the proposed device design. The results of a test of a short-circuit of a 3.3 kV direct current contact network in the Dragunskaya-Novokievskaya-Lubinskaya section are presented. The main directions for further work are determined.

In article temporary characteristics and results of the analysis of operation of the relay - the differential shunt are considered at full removal of a package of steel on a branch of smaller section. Conclusions are drawn on opportunities of its application at pass by the electrorolling stock of the isolating interfaces. The method of the choice of settings of the relay - the differential shunt, considering time delay at its operation is offered.