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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 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.