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The subject of the research is the power thyristor converter of AC electric locomotives and its influence on the power factor of the locomotive. A new method for increasing the power factor of AC electric locomotives with thyristors power converters is proposed and analyzed. These electric locomotives include locomotives of the 2ES5K, VL85, EP1 series, etc. At the initial of the paper, the existing methods of increasing the power factor are briefly considered and their disadvantage in comparison with the proposed method is indicated. The drawback of existing converters is also analyzed, which consists in the presence of a thyristor opening delay at the beginning of the supply voltage half-cycle. The proposed method implies the modernization of the control circuits of the thyristors of the converter, due to which, at the beginning of the half-period, a control current is spontaneously created on the control electrode by means of the supply voltage. As a result, the thyristors open with a minimum delay after the start of the half-cycle. To verification the effectiveness of the proposed solutions, a computer simulation of the operation of the power circuit of an electric locomotive in the ORCAD program was carried out. Simulation was carried out for two options: a power circuit with standard converters and a power circuit with converters upgraded in accordance with the proposed method. During the simulation, the change in the value of the power factor of an electric locomotive was investigated at different currents of traction motors, zone and angle of regulation. Analysis of the oscillograms of converter various arms currents the revealed that when using the modernized converters, the moment of the end of the network switching occurs earlier than in the standard circuit. There is also no area with negative voltage at the output of the converter at the beginning of the half-cycle. At the end of the paper, the values of the electric locomotive power factor are given under various conditions. These results show that the use of the proposed method increases the power factor of an electric locomotive by an average of 1.2 percentage points.

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 article presents a method for determining the thyristor shoulders of the rectifier-inverter converter (inverter) of an electric locomotive, on which the control pulses are passed. The method is based on the analysis of the duration of the current switching of the thyristors of the inverter shoulders and the rate of rise of the rectified current in the inverter circuit of the electric locomotive. The implementation of the method is carried out by refining the software of the microprocessor control system of the electric locomotive. The simulation of electromagnetic processes of rectifier inverter Converter of AC locomotive series 3es5k "Ermak" in the mode of regenerative braking during emergency operation is carried out on the example of missing control pulses on thyristor shoulders VS2 and VS7. As a result of modeling, data are obtained that confirm the effectiveness of the method proposed by the authors

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.

This article is devote to the development of software for analyzing and transforming data from studies of the collector surface traction motors using a device of control profile commutator PKP-4M. The use of this computer application during the processing of the experimental data will improve the reliability of the control profile of the commutator, and to calculate the main diagnostic parameters characterizing the effect of the profile on the commutation process.

In the article suggests a changing the algorithm of the rectifier-inverter converter electric locomotive VL85. This will allow the individuallyto regulatevoltageon traction engines. In this case willpreserve a singlecentralized system ofcontrol of allelectricconverters. The proposed solutions may be used for liquidation started spinning of wheel locomotive. Tractive force the remaining wheelsets will not decrease.

With the purpose of providing capacity on the West-Siberian railway, in recent times, adjustable reactive power compensation devices have been introduced. The schematic construction and parameters of such devices on the market are significantly different. In connection with this, it is necessary to choose from the set of schemes the most effective, corresponding to specific technical and economic conditions. The article assesses the power losses in the main equipment of two devices from different manufacturers, namely static thyristor compensators of reactive power produced by "KER Holding" Kazan and "Aidis groups" Moscow, installed on the Alambay and Novaya Dubrava sectional posts of the West Siberian Iron roads. The power losses in the equipment are calculated taking into account additional losses from the influence of higher harmonic components. The analysis of the circuit design of both devices in terms of loss reduction is carried out. Dependences of power losses in their elements on the generated reactive power and the current of the thyristor-reactor group are constructed. Probabilistic functions of the distribution of the current of the titrator-reactor groups of devices are given at preset settings. The results of measurements of power consumption of devices for own needs are presented. The effect of reducing power losses in the traction network from switching devices with losses in their main equipment is compared. On the basis of the work done, the elements with the greatest losses are identified. The features of each device, affecting the power loss in the main equipment, are described. Conclusions are drawn about the effectiveness of the schemes under consideration. Methods for reducing power losses in basic equipment and consumption for energy consumption are proposed.