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The article is devoted to the improvement of regression models of the proper resistance of the elements of a grounding device when passing a sinusoidal current through it in order to increase their accuracy. This type of models allows for a fairly high accuracy in assessing changes in physical quantities. The accuracy of the description depends on the number of factors taken into account when constructing the model and the degree of the regression polynomial. The models presented in the article are based on an experiment to measure the proper resistance of the elements of a grounding device, in which a sinusoidal current with the following frequency was passed through cylindrical conductors of four diameters: 10 mm, 16 mm, 22 mm, 28 mm: 25 Hz, 50 Hz, 100 Hz, 200 Hz, 400 Hz, 800 Hz, 1000 Hz. The strength of the passed current varied from 6 to 40 A with a step of 2 A. Due to the large number of factors and the complex nature of the physical processes occurring inside the conductor, a multifactor regression analysis was used. The accuracy of the regression models presented in the article was increased by increasing the degree of the regression polynomial. After constructing the models, their adequacy was assessed and the coefficients of the obtained models were assessed for statistical significance. The adequacy of the models was assessed using the Fisher criterion. As a result of the assessment, it was established that the obtained models are adequate and accurately describe the experimental data. The practical significance of the research is that increasing the accuracy will allow obtaining more reliable information about the value of the intrinsic resistance of the elements of grounding devices, which in turn will simplify further automation of the design and modeling process of grounding devices.

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.

The question of the possibility of using concrete foundations support of a contact network as earthing. The analysis of the impact of the construction of the foundation for the spreading re-sistance. The results of the calculation of spreading resistance of the anchor bolt foundation metal support on the proposed formula.

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.

Corrosion processes at various constructive changes of grounding system of traction substation are considered: construction of new cable lines, expansion of the territory of substation, etc. Calculation of corrosion processes of the grounding system consisting of three electrodes is carried out: steel in concrete, the metal gauze in soil, a steel vertical electrode in soil. Results of calculations are presented, the analysis of corrosion processes is made under various conditions.

The mathematical method of calculation of currents of corrosion of two models of grounding models - ekvipotentsialny and nonkvipotentsialny is presented. Soil and electric corrosion of both models is considered. The mathematical method of calculation of sizes of corrosion currents and potentials will allow to estimate a corrosion condition of elements of grounding system of traction substation.

The paper deals with the protection of the buried structures under the influence of DC traction network stray currents. The paper presents an algorithm for joint operation of drainage units for simultaneous protection of the grounding grid and two isolated underground conductors with priority protection of the grounding grid. The proposed algorithm of joint drainage protection of buried structures allows providing the possibility of optimal protection: simultaneous keeping of the protective potential of buried structures with the minimum required drainage current, which allows reducing energy costs, reducing corrosion damage and extend the operating life of buried structures.

Recently, during overhaul of the railway track using modern materials such as geotextiles and penoplex. In turn, they make significant changes to the structure of the ballast, t. To. Are almost insulators. OSTU experimentally it has been ascertained that the contact resistance in the case of using a new type of cloth can be raised to 45 - 150 Om*km. Obviously, this leads to a significant increase in the capacity of the rail relative to a distant ground and can cause injury to personnel operating the traction members network. To determine the capacity of the rail at any point area must take into account the redistribution of power in the elements of the rail network, ie. E. In the rail and the transition resistance «rail - the land». The rail network is characterized by longitudinal rails Zp kilometricheskim resistance, transition resistance «rail - land» rp-s, and the characteristic impedance ZB kilometricheskim spreading factor γ rail network. Analysis of the results lead to the following conclusions: 1) contact resistance «rail-to-earth» has a significant impact on the value of the potentials arising on the elements of reverse current flow circuit; 2) the growth of the resistance «rail-to-earth», associated with seasonal fluctuations in soil resistivity, as well as in recent times, with the capital reconstruction of the roadbed, resulting in a significantly longer (up to several tens of kilometers) area, for which the potential can reach hazardous the value of human life; 3) in the circuit mode on a rail (m. E. When a metal short circuit) almost always rail network will occur potentials exceeding admissible values for several kilometers in both directions from the point of fault, which leads to removal of the dangerous potential at all metal construction connected with the rail and therefore requires a review of the principles of grounding structures.

The paper deals with the influence of stray currents on underground metal structures located near the traction rail network. The paper presents a system consisting of a traction rail network, a grounding grid and two isolated underground conductors located under the stray currents influence caused by electrified railway transport. Analytical expressions for the calculation of the distribution of electrical quantities in underground structures with their mutual influence were obtained. The expressions were obtained using Hartley integral transform, which in contrast to the Fourier transform allows carrying out integral transformations only with real-valued functions. The obtained expressions allow determining the zone of dangerous influence of stray current and can be used in the design of underground structure protection.