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Railway transport faces the challenges not only to ensure uninterrupted transportation of national economic goods, but also to develop new locomotives and increase the efficiency of their use. In particular, the currently accepted mode of starting diesel locomotives of the UzTE16M type leads to additional consumption of fuel resources, therefore, research on the development and improvement of the conditions for starting diesel locomotives of this type is relevant. Based on the study of previous studies and designs of various systems in order to facilitate the start of diesel locomotives with electric transmission, it is necessary to establish the available reserves of the power circuit and control circuits. The article considers a mathematical model of torsional oscillations in a diesel generator start-up system with two concentrated mass moments of inertia. Torsional oscillations between the traction generator and the crankshaft of diesel locomotives of the UzTE16M type have not been previously considered. In this article, the problem of torsional oscillations of the reduced masses of the armature of the traction generator and diesel engine in the mode of starting the DG from the battery and additional devices is solved. The Lagrange method has derived a system of mass oscillation equations based on generalized coordinates of elastic oscillations between the masses of the armature of a traction generator and a diesel engine with a variable mass moment of inertia. For the resulting system of equations, the solution is performed by the method of operational calculus, taking into account the accepted functions of mass moments of inertia, moments of driving forces and resistances. Conclusions are drawn that the operation of the diesel starting system on diesel locomotives of the UzTE16M type is determined by the functions of the reduced mass moment of inertia of the diesel, the driving torque and the angular velocity function; the resulting solution makes it possible to calculate the driving torque and the range of angular velocity changes when starting the diesel generator set of UzTE16M locomotives for further comparison with experimental data; when using the recommended electric scheme for starting a diesel locomotive, an increase in the driving torque of the diesel crankshaft and the angular acceleration speed of the traction generator armature is achieved. Based on the developed model, it is recommended to determine the angular velocity of the diesel crankshaft.

The existing protection does not provide protective potential of traction substation grounding grid for the entire period of operation. This disadvantage is removed by improving of automatic drainage unit. The basis of the automatic drainage system is automatic control of drainage current by changing the pulse width of current. This method of current control allows the defined potential remain at the set value. The article presents a functional diagram describing the basic units of the improved automatic drainage unit. The results of the automatic drainage unit tests illustrate that the automatic drainage unit limits the current flowing through the grounding grid to the traction substation, allowing the potential remain at the set value Improved automatic drainage unit has great advantages in relation to existing and operated drain units at this moment and it can be recommended for introduction to the electrification infrastructure of the railway industry. Also this automatic drainage unit can be used for protection of other metal underground structures such as pipelines and other metal structures influenced by stray currents.

In the article the finite element model of the electrical contact pin wire - collector strip, which takes into account the complex interaction of electric and thermal processes. As the contact wire is selected worn MF-100, the current collection plate - two brands VJZ-metal and graphite. Microgeometry the body surface at the contact point is obtained based on the model of Greenwood - Williamson. It was considered the two extreme cases of possible contact between the contact wire to the plate. The results were analyzed and compared with the known experimental data. Calculated at what proportions contact force and contact current due to burnout occurs spark or arc. Identify ways to improve the model.

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.

The paper is devoted to the calculation of the electrical quantities distribution in the system of three conductors. The first conductor is located on the surface of a uniform soil and the other two conductors are located at depths of h and h . As result, analytic expressions of current, potential and leakage current density in the first underground construction with considering the influence of the second construction was obtained. The influence of second construction increases the value of electrical quantities in the underground construction. The analytic expressions were obtained using Fourier transform method. The analysis showed the influence of the leakage current and insulation resistance of the second construction on the electric quantities distribution in the first construction

The article presents a method of the additional resistance calculating of ground grid drainage unit. This work has two main objectives: development of algorithm for determining the optimal values of additional resistance and to study the possibility of reducing losses in reverse traction network through drainage unit of traction substation. The calculation is carried out with a view to ensuring the normative values of the protective potential on the grounding grid and minimize losses in the reverse traction network. The method is based on the application of the reciprocity theorem, which allows to change the direction of the currents from the source to the load on the reverse one if the system is linear. The calculation of the values of additional resistance and power loss in the reverse traction network for average current on the considered traction substation of the Western-Siberian railway. In results the selection method of optimal values for the additional resistance is offered. This method can be used for designing of traction substation grounding grid protection.

In article methods of valuation electrical parameters and mathematical models of electic processes of reinforced concrete construction are considered. The conclusion that influence of reinforced mesh was not taken into account in describe models had been done. Method for prediction of reinforced concrete foundation which based on equation system of electric field in conductors and finite element method and allowed explicit geometry of object include reinforced mesh was suggested by authors. Authors done the assumption about invariability of potential of reinforced mesh which covered of concrete layer for direct current and alternating current due to ratio of steel and concrete resistance. Realization of nethod was done by dint of software complex Comsol Multiphysics. Research object was reinforced steel foundation TSS-4, which is located in ground. Result of research was represented color epure of potential distribution and line of current density. Reinforced concrete construction current and current which flow into armature were determined by dint of integration of normal current density on surface where set the external potential and surface of armature. On the grounds of determine values of model current resistance of model depending on resistivity of concrete and ground were calculated.

The article presents the relevance of the use of sources of low-potential, secondary thermal energy, as well as a method for calculating the dependence of the propylene glycol temperature on the depth of a single-well coaxial collector, with constant values of the parameters of the geothermal well. The proposed methodology of the geothermal reservoir, allows to determine the optimal depth of the well, in which the increase in the temperature of propylene glycol in practical terms does not change, respectively, further drilling becomes economically inefficient.

The article presents the results of the studied soils on physical and thermophysical characteristics in the territory of the city of Omsk. The lack of such data can lead to erroneous calculations in the design of ground probes using low-potential energy of the earth. A method for determining the minimum distance between wells is proposed, which allows to eliminate soil freezing and increase the efficiency of heat transformers.