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This article describes the standard field reduction system of traction electric motors of a contactor-resistors type using inductive shunts, its drawbacks are revealed. An improved field reduction system of traction electric motors of an AC locomotive based on IGBT transistors has been developed and proposed. The proposed solution will allow to exclude the copper-containing inductive shunt from the power circuit, while providing reliable protection in non-stationary operating modes of the electric locomotive, as well as reduce electricity consumption for train traction. To prove the advantages of the proposed the field reduction system of traction electric motors, a method of comparative analysis of electromagnetic processes of the mathematical model of the standard and proposed systems of the field reduction of traction electric motors of an electric locomotive obtained in the MatLab Simulink environment was applied. As a result, it is proved that the implementation of the field reduction systems of traction electric motors using IGBT transistors with the developed control algorithm provides an increase in the power factor of an electric locomotive on average by at least 4%, and also significantly reduces the ripple current of the traction electric motor.

An urgent issue is to increase the power factor of electric rolling stock. One of the ways to increase the power factor in the traction and regenerative braking modes was proposed by the scientists of IrGUPS - this is the use of a rectifier-inverter converter on IGBT with modified control algorithms. This solution allows to significantly reduce the consumption of reactive current from the contact network, increase the capacity of railway sections, increase the technical speed, increase the efficiency of the traction power supply system, and also increase the amount of electricity returned to the contact network in the regenerative braking mode. The study of the performance of this converter is of interest. The transported volumes of goods on the railway lines of the Russian Federation continue to increase. One of the key links in ensuring the specified growth rates of tonne-kilometer work is the availability of powerful traction rolling stock equipped with an appropriate traction drive. A powerful traction drive is characterized by the consumption of significant current. To ensure its flow over the arms of the converter, a parallel connection of power semiconductor devices is used. For modern converters of electric locomotives, 4 parallel branches of power switches are used in the arm. The features of the parallel operation of the arm branches affect the performance of the converter on IGBT transistors. This article proposes to consider one of these features, namely the influence of parasitic inductances on the distribution of currents in the parallel branches of the converter, depending on the connection point of the AC power bus. The study was carried out using the Matlab Simulink software package. The article discusses various options for the topology of connecting power buses and presents diagrams of the distribution of currents in the parallel branches of the arm for each connection method. An assessment was made of such parameters as the spread of the peak current of switching on the branches of the arm, the time of current equalization during the conduction period, and the difference in the magnitude of the current in specific branches. Based on the results of the study, as well as taking into account the existing dimensions for the equipment of AC electric locomotives, a conclusion was made about the most optimal option for connecting power buses.

The article deals with the issue of improving the energy efficiency of DC and AC electric locomotives operated at the enterprises of JSC “Russian Railways». The main goals and objectives of the development program and energy strategy of JSC «Russian Railways» are analyzed and briefly considered. In accordance with these tasks, the relevance of scientific research in the field of improving the energy efficiency of electric locomotives is substantiated. The current data on traction rolling stock, on modern traction resource management systems and on Russian and foreign scientific research in the field of energy efficiency are analyzed. As a result of the analysis, it was found that most of the studies are aimed at studying the influence of key operational factors on energy efficiency indicators, so, in this case, on the specific power consumption for train traction. However, the reverse question has been poorly studied - the selection of the train mass and the technical speed on the basis of a preliminary assessment of the specific power consumption for train traction by analyzing the statistical data of trips on a certain section of the railway. The purpose of this study is to assess the possibility and develop a method for determining the optimal values of the key parameters of the operation of electric freight locomotives in order to achieve maximum operational efficiency in relation to them according to the criterion of energy efficiency. Two models were created in the program «Complex of calculations of traction power supply» (CORTES) - for DC and AC electric locomotives, describing the dependence of the energy efficiency indicator (specific power consumption for train traction) on operational indicators, such as the train mass and the technical speed. The initial data for further modeling were obtained by modeling trips on a conditional site.

The paper deals with benefits of a new rectifier-inverter converter of an electric locomotive based on IGBT-transistors. Main directions of heavy haul traffic's development are considered for Siberia and Russian Far East electrified railways. Throughput and carrying capacity of power supply devices extremely depends on the voltage level in the catenary network of electrified sections of railways. Objects of our research are electric parameters of the 25 kV, 50 Hz AC traction power supply system. Operation parameters of two different types of the electric locomotive’s rectifier-inverter converters are calculated and discussed. We investigated operation parameters for thyristor-based and IGBT-transistors- based rectifier-inverter converter. Current and voltage curves for the thyristor and the transistor type of the rectifier-inverter converter are given and discussed. Similarity factor of current curves for electric locomotives was calculated by equivalent sinusoid’s .method. Quantitative assessment of the voltage level, currents and voltage losses in the AC catenary network is given. The graph-analytical method was used for constructing currents and voltages vector diagrams. It is proved that electric locomotives with a new rectifier-inverter conversion based on IGBT transistors provides a reducing of the total voltage losses in three times in the traction network comparing the thyristor conversion's operation.