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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.

The article describes the structural scheme, the algorithmic basis, functional composition and some technological characteristics of the hardware and software of information system of operating control parameters of the electric power in the traction power supply network, structural peculiarities of information-measuring complex, the hub characteristics of the data collection substation, type of equipment used in information and computational complex structure of servers for processing and storage, data volumes and characteristics of the necessary communication lines.

The article is devoted to the issue of power loss measurement in DC traction networks. The purpose of the work is to define the indicators characterizing the degree of determining the energy loss values accuracy when using the method of restoration of the train situation. In the article the analysis of methodical error the value arising at measurement of power losses in a traction DC network is conducted. The occurrence of the error is caused by the indirect measurement method, which is based on the principle of synthesis of instantaneous circuits in real time. The synthesis is based on direct measurements of currents and voltages on the busbars of adjacent feeding and switching points, for example, a traction substation and a sectionalizing station. The data obtained are processed in accordance with the algorithms adopted in the article, as a result of which the coordinates of loads and their current consumption are calculated. In the process of synthesizing instantaneous circuits, it is possible that such a train situation may occur, which will lead to the emergence of a methodical measurement error, due to the peculiarities of the logical and mathematical apparatus of the train situation recovery method. In this paper, has been performed a probabilistic analysis of the possibility of occurrence of methodological error when several traction loads will be present simultaneously on the measuring section, that is, the dependence of the occurrence of the measure of uncertainty on the daily size of train traffic and the dependence of the occurrence of the measure of uncertainty on the minimum inter-train interval. As a result of the study, the proposed method application the limits were established by energy loss measurement the permissible error the criterion. The methodological error the value of the measurement at different variants method of movement on the railroad studied section was assessed

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 outlines modern approaches to determining the maximum permissible continuous current of current collectors when stopping and in motion. The features of techniques that reliably take into account operational factors when conducting tests in laboratory conditions are considered. A mathematical model is given for studying the distribution of current load in emergency mode of breaking a current-carrying shunt.

Now there is no efficient decision to estimate a corrosion condition of an underground part of reinforced concrete support of contact network which is not demanding digging of a support. This problem makes actual a task of development of a hardware and software system of definition of a corrosion condition of an underground part of reinforced concrete support of contact network. As a result of work the software module allowing to realize panoramic shooting of an internal surface of an underground part of a support, to increase quality of the received images, to carry out searching of inhomogeneities and to determine their geometrical parameters, and also to make the analysis of the found inhomogeneities. Implementation of results of work will allow to reduce time and labor costs, and also to increase efficiency of diagnostic works on support of contact network.

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 describes the design features of the current collection system of the Moscow monorail and revealed its shortcomings, limiting the possibility of increasing the speed of electric rolling stock. The features of a promising new generation of monorail transport system with increasing speed (up to 150 km / h), the message "city - the airport," which is proposed to use the contact current collection system with flat working surfaces of the current collector and the current lead. The aim of the work was to develop measures and technical solutions for improving the current collectors to provide reliable, cost-effective and environmentally-friendly electric power transmission on board the electric rolling monorail transport systems. The proposed technical solutions have allowed to increase the average life of the contact elements of the current collectors of electric rolling on the active sites of the Moscow monorail from 30 days to 5 months. A preliminary design and manufactured model sample collector rolling device for the new generation of monorail transport system with increased speed. A basic model of the pantograph, which allows to unify all the major components and spare parts for the current collectors of options for different speeds, load current, and other operating conditions and choose the appropriate model, taking into account technical and economic feasibility. The results can be used for the improvement of existing and development of new designs for current collectors of electric rolling monorail transport systems for the high speeds.

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.

The quality of a track circuit monitoring system is defined to the great extent by its ability to automatically analyse the acquired data, i. e. identify the state of a track circuit. Machine learning techniques can be applied to implement this functionality. Designing a machine learning algorithm requires a learning data set from the subject domain. In this article we discuss a basic principle of track circuit mathematical model design that could be used to generate such data set. We also apply this principle and a combination of some existing methods to design and demonstrate a mathematical model of the 25 Hz AC track circuit.

In article the algorithm of operation of the existing regime automatic equipment of transforming aggregates is considered. Earlier it was read that use of automatic equipment of switching on switch-off of reserve transforming aggregates is an effective remedy of lowering of losses in case of regulation of power of substation depending on tractive loading. Defining factors of assessment of efficiency of automatic equipment are the current and temporal settings, and also restriction of number of switchings in days. The analysis of diagrams of tractive loading showed that there is rather large number of temporal intervals where operation of automatic equipment is ineffective. On the one hand it is connected to the fact that loading is above a point of equality of losses in case of one and two transforming aggregates quite short time, and automatic equipment connects the reserve transforming aggregate already in the course of lowering of loading and disconnects it after a temporal setting. On the other hand - operating restriction of number of switchings of the reserve transforming aggregate in days doesn't allow to gain the considerable economic effect. The decision on use of regime automatic equipment with the existing settings can be the positive if at the same time the estimated effect in the form of abbreviation of losses of the electric power is above cumulative damage from switching of the reserve transforming aggregate. Regime automatic equipment in most cases, it is necessary to consider not as means of obtaining economic effect, and as means of reliability augmentation of operation of semiconductor rectifiers at the peak moments of loading what in turn influences reliability of electrical power supply of pull of trains in general.

Resistive heating of the pantograph head due to the flow of traction current through the conductive elements of the upper node, has an uneven distribution along the frame structure and depends on the location of the contact wire on the insert. The aim of the work is to develop a mathematical model for calculating power losses in the pantograph panhead, allowing to estimate its value, taking into account the zigzag of the contact wire during the movement of electric rolling stock. The subject of the study is the pantograph panhead. The paper gives an example of calculating the frame skid of a pantograph equipped with carbon strips. Experimental studies of the current distribution over the shunts of the panhead depending on the position of the contact wire were carried out in February 2021 in the laboratory "Designs of contact networks, power lines and current collection devices" using a complex for testing current collection devices. The calculation of the heating power of the panhead is determined by the Joule-Lenz law. The results of the calculation showed that the maximum heating power is observed when the contact wire is in the middle of the panhead, while the places of the greatest losses located along its edges are above the places where the shunts are attached. The model makes it possible to obtain a functional dependence of the heating value along the panhead. The obtained results of the skid heating power distribution make it possible to supplement the complex model of the thermal state of the pantograph developed at the Omsk State Transport University with the participation of the authors of the article. The versatility of the developed model makes it possible to investigate various zigzags of the contact wire and evaluate the effect on the distribution of traction current along the panhead, depending on the location of the shunts and their number.