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The experience gained in the operation of high-voltage vacuum circuit breakers VBO-25-20/ 630UHL1 indicates an incorrect assessment of the mechanical resource of its individual components and elements. Despite the repeated improvement of the design of the main switch drive, applicable both as part of the new «Ermak» series locomotives starting from number 1000 series, and in earlier numbers, the dynamics of malfunctions continues to persist to the present time. One of the most important elements of the main switch is a latch designed to hold the elements of the drive mechanism in the on position, the failure of the latch entails the failure of the entire section of the locomotive. The article considers three latch upgrades previously proposed by the manufacturer, a kinematic scheme of the drive with a vacuum arc-extinguishing chamber of the switch is developed, the parameters of the preload and trip springs in the drive are calculated, the forces operating during operation are determined. On the example of the latest modernization of the latch using the finite element method in the SolidWorks Simulation software package, a strength calculation was carried out, according to the results of which the stresses arising in its design were determined. As a result of the analysis of the finite element model, the forces critical for the structure are determined, a graph of the dependence of the structural strength margin and the maximum stress in the structure on the acting forces is developed. According to the results of the study, the force at which the most favorable value of the safety factor is provided is determined, for which it is proposed to reduce the critical force by changing the parameters of the compression springs and disconnecting the drive of the arc extinguishing chamber. A loading diagram with the drawing dimensions of two modified springs has been developed.

When modeling the traction power supply systems, reflecting the processes of interaction of electric traction power supply and mobile electrical loads (electric and electric) is one of the elements of movement imitation organization trains in space. The effect of moving trains in simulations (MI) in MatLab on schedule at the analyzed site traffic necessitates sequential switching models of electric rolling stock (EPS) to the traction network, so that its effect is realized by moving the site. However, in this case, there really is not the processes taking place in reality. This is due to the realization of the simulation method of discrete movements, characterized in that the CSE, one located on a cell - the traction network model at one time, thereafter jumps to another. While EPS previous cell is switched off and switched on the next cell. Thus there does not exist in reality switching processes that distort the results of the studies. Methods to reduce the negative consequences of such distortions are addressed in this article.

The calculation of the performance indicators of the traction power supply system in steady-state modes is focused on solving a wide range of tasks related to the choice of parameters of the power equipment of traction substations, the placement of linear equipment, the cross section of the contact suspension, the comparison of options for technical and economic indicators. Currently, the appearance of various regulated devices in the traction power supply system necessitates the improvement of calculation methods and algorithms used in various software complexes. In this paper, the issues of constructing substitution schemes for modeling the operation of the traction power supply system in steady-state modes, taking into account the devices for automatic switching on and off of the backup converter unit of the traction substation and the accumulation of electricity. The corresponding substitution schemes and fragments of calculation algorithms that take into account the characteristics and operating modes of these devices are presented. The use of the proposed substitution schemes allows us to take into account in the calculations the difference in the external characteristics of the converter units, to assess the compliance of the automation settings with the level of electric traction load and the effect of the device on the voltage level on the substation tires and in the contact network, the load capacity of traction substations, and for the accumulation device, taking into account the charging and discharge characteristics, to additionally assess the impact on the effectiveness of regenerative braking. The proposed algorithms of the devices are designed to improve the methods of calculating the indicators of the traction power supply system. The paper proposes an improved method for calculating the indicators of the traction power supply system, based on simultaneous traction and electrical calculations, based on the database of calculations performed for various conditions of electric rolling stock on the railway section.

In this article, the authors have studied the electromagnetic processes of an inverter based on thyristors and IGBT transistors of an AC electric train in the regenerative braking mode. To accomplish this task, a method was used to compose instantaneous replacement schemes and systems of differential equations corresponding to a certain time interval of the rectified voltage diagram and the currents of the inverter arms. On the basis of the study were given the disadvantages of thyristor inverter and the advantages of transistor.

The drawbacks of the step-by-step automatic voltage control system under load AVC and the non-contact automatic voltage control system NAVC with the reactor switching device of the converter transformer used in the traction power supply are analyzed. The scheme of a thyristor-reactor switching device (TRSD) connected to the primary winding of the transformer is considered. A brief description of the operation of a transformer with TRSD and the procedure for calculating the symmetrical and asymmetrical external natural characteristics of a converter unit with TRSD are given. Based on the dependence of the energy indicators of the converter unit on the resistance of the uncontrolled reactor TRSD, a method is proposed for calculating the rational resistance of an uncontrolled reactor, where the power factor of the converter unit is taken as the criterion of rationality. The method includes two stages: the first is the calculation of the values of the power factor of the converter unit depending on the resistance of the uncontrolled reactor and the load current of the converter unit; the second is the determination of the average load current value of the power factor of the converter unit for each considered value of the resistance of the uncontrolled TRSD reactor and the determination of the rational for the considered external natural characteristics of the unit. In accordance with the presented methodology, the calculation of the minimum permissible and rational resistances of the uncontrolled reactor TRSD as part of a converter unit with a converter transformer TRDP-16000/10 was made. Taking into account the selected rational value of the resistance of the uncontrolled reactor TRSD, a calculation was made and the external natural characteristics of a converter unit with a TRSD and a converter transformer TRDP-16000/10 are presented. The performance check of the presented calculation method for solving the problem of choosing the rational resistance of an uncontrolled reactor was carried out on a physical model of a converter unit with a TRSD, with a 12-pulse rectifier unit, with a 30 kVA transformer and a linear primary voltage of 380 V. Comparison of experimental and calculated values showed a slight discrepancy, the permissible error was not exceeded. Determination of the resistance value of an uncontrolled reactor based on the developed methodology provides the highest values of the power factor of the converter unit.

The purpose of this article is to analyze the voltage drop in the contact network caused by poor-quality operation of an alternating current electric locomotive when passing heavy trains. Heavy-haul traffic is considered today as a valid and necessary tool for increasing weight norms and increasing the throughput of railway sections. The article provides statistics on the passage of heavy and connected trains on the Krasnoyarsk railway for 2019 and 2020. For the effective use of heavy traffic, it is necessary to solve a number of problems, one of which is to reduce the voltage in the overhead network when passing heavy trains, this negatively affects the speed of the train along the haul, the conditions for cooling the power equipment of the electric locomotive deteriorate, etc. As a result of the analysis of the operation of the thyristor rectifier-inverter converter, a number of disadvantages were revealed. The reason for the low power factor of the electric locomotive lies in the use of an outdated element base based on thyristors, their closure is carried out only in the next voltage half-cycle, long-term switching and a large opening angle of thyristors leads to a significant reactive current in the contact network. Based on the analysis the voltage losses at the current collector, it was concluded that it is necessary to reduce the duration of the switching process of the arms of the rectifier-inverter converter, in which a short circuit occurs in the secondary winding of the traction transformer. An alternative version of the converter based on fully controlled semiconductor devices - IGBT transistors is proposed. The ability to open and close at any time of such elements allows you to minimize the phase angle and increase the power factor. Due to the almost instantaneous switching of transistors, the distortion in the contact network is minimized.

In article the reasons of shutdowns of high-speed switches of a direct current are analysed and distribution of the disconnected currents is received. Such numerical characteristics as population mean and a mean square deviation of function of distribution of the currents which are disconnected by the high-speed switch are considered. The hypothesis of distribution of probability of refusal in operation of the switch is checked. Conclusions are drawn on applicability of the given calculation methods for definition of admissible number of shutdowns of high-speed switches on sites of traction network of a direct current.

In article possibilities of decrease in number of not selective shutdowns of high-speed switches by use of the relay - the differential shunt are described at full removal of a package of steel on a branch of smaller section. Results of experimental evaluation of the work of the relay - the differential shunt are given at full removal of a package of steel in a branch of smaller section and its trial operation. Conclusions are drawn on earlier undescribed property of the relay - the differential shunt, at full removal of a package of steel on a branch of smaller section - with increase in speed of increase of current, the considerable time lag of operation of the relay appears.

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.

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.

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.

This article examines the enhancement of local control and monitoring systems for railway turnouts at stations based on wireless technologies. Instead of the traditional four-wire turnout control scheme, a wireless communication system utilizing a microcontroller and LoRa radio module is proposed. A custom-developed application installed on a tablet authenticates users via login credentials, password, and an NFC card. The application provides functionalities such as viewing the current status of the turnout, switching it to the required position, sending control commands, and recording and archiving operational data. Each command issued is saved both in the tablet’s internal storage (local database) and in a remote server database via the internet. For every command, parameters such as date, username, turnout number, status, and type of operation performed are logged. The newly developed scheme and mobile application enable wireless control of turnouts from the locomotive cabin, creating the possibility of performing shunting operations without the involvement of a shunting operator. The article presents the system’s operating algorithm, user interface, schematic solutions, and key functions of the tablet application. Furthermore, a structural diagram of the wireless turnout control system and a practical model based on an experimental prototype are provided. During the development of the software and hardware solutions, the requirements for ensuring traffic safety based on switch control schemes were thoroughly analyzed and taken into account through the following measures: prior to switching to local control, the section’s occupancy status is automatically verified; the switch position is visually indicated on the tablet; and all commands issued by the user are archived in both local and server databases. Furthermore, the ability to remotely control the switch enables safe operation without the involvement of a maneuvering agent. The proposed approach is considered technically suitable and practice-oriented for implementation in the automation of railway infrastructure.