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In the article the possibilities of improving the adjustment properties and technical characteristics of electric rolling stock with collector traction motors are considered. Semiconductor devices can improve the smoothness of the traction motors start-up due to a more even voltage increase, smooth regulation of the field current in the traction and braking modes. Variants of simplified power circuits of eight-axis direct current electric locomotives with a minimum number of switching electrical devices have been developed, allowing to reduce weight and size of the equipment, increase the reliability of power circuits operations. Circuit solutions for protecting the wheelset of an electric locomotive from boxing and skidding by enhancing the traction motors field are considered. The role of semiconductor converters in the improvement of rolling stock with a combined and dual power is noted. The ways to improve the efficiency of electric braking by collector traction motors are listed. The necessity of using adaptive microprocessor control systems for semiconductor converters for expanding their functional capabilities and realizing optimal parameters of direct current rolling stock is noted.

The article presents the results of experimental researches of process of commutation in traction DC motors. In order to generalize the results of tests of low power engines for electric locomotive’s traction motors, belonging to high power engines, by using the theory of similarity and dimensions we defined the ranges of varying parameters of the operation mode in the experiments. In result of the conducted researches proved the effectiveness of the parameters of laws of distribution of intensity sparking to improve the reliability of the test as low power engines and high power engines.

In this article the generalized results of researches of change of intensity of wear of electrical brushes in the traction motors of electric locomotives. On the basis of the conducted research the author proposes an algorithm to predict the operating life of the brushes, given the parameters of the operation. In order to increase the reliability of the calculation has been developed algorithms, which allow additionally taking into account the effect of the collector’s surface.

The article describes themain types ofdamageinsulatorscontact network, presents statisticsfortheirfailures. Identified weaknessesin existing methodsof diagnosingsayabout the relevance ofthe problem, especially in the areasof railwaysDC. Made experimental investigationson the measurementof the electrostaticfield on theinsulator strings. Analysis of the studiesshowed that the presencein the string of faultyinsulatorsleadsto an increase inthe electrostatic fieldaround them. Proposed a technicaldevice noncontact measurementof electrostatic fieldandmethod of determining thefaultyinsulatorin the string.

The article presents a universal energy-efficient stand for load testing of asynchronous traction motors, and DC motors. It is proposed to use two options of schemes for testing of traction DC motors with serial excitation and asynchronous motors, and traction motors DC parallel (independent) excitation and asynchronous motors, each of which allows you to implement energy-efficient test method - the method of mutual loading. Given the advantages of the use of the proposed stand. The calculation of the main parameters recorded during the test: currents, voltages and power are invited to perform with the help of mathematical models. Each of the mathematical models takes into account the work of the subjects of the asynchronous traction motors and traction motors DC series or parallel (independent) excitation) by the method of mutual loading: electrical and mechanical link. In conclusion, the article sets out the intended results from the implementation of energy-efficient universal stand for load testing of asynchronous traction motors, and DC motors.

This article describes the algorithm for polynomial interpolation analog-to-digital converter with a duration of calibration1 ms. There is an example of reconstruction the missing values for a given accuracy of processing the input signal

The article deals with the problem of diagnosing the technical condition of the collector-brush unit of DC motors. The topicality of this problem in the engines operating on the railway transport, which are in the most severe operating conditions, is particularly noted. These studies are aimed at improving the reliability of diagnosing the technical condition of the collector-brush unit through the use of a new method of diagnosing the condition of collector DC motors’ commutation. The proposed method of diagnosis is based on a new principle of processing diagnostic information about the spark pulses under the brushes. The article presents the histograms of the distribution of the pulses' intensity of different sections of the armature winding. The research conducted an experiment using a digital control device that allows to identify and digitize a useful diagnostic signal from multipolar brushes with a high sampling rate and transfer it to a computer. Analysis of the experiment’s results showed that the average value of the pulse’s area increases with increasing the spark’s intensity. Nevertheless, severe sparking at the collector leads to the law of distribution becomes double-modal, and as a result, dramatically increases the standard deviation of the values of the pulses’ areas. Described effect makes misinformation in the diagnosis procedure using the parameters of the laws of distribution of the spark’s intensity. The proposed method of diagnosis allows to eliminate this effect. The copyright for a new method of diagnosing is protected by a patent.

Single-phase transformer with an additional tap at the middle point of the secondary winding is a very common element in the various electrical circuits, including on-board electric rolling stock. A typical case is powered from the transformer zero full-wave rectification circuit. The aim of the article is to provide a detailed description of the computer model developed by the author of said transformer, built on the basis of a combination of circuit and operational design principles. The proposed model can also be used to describe the process in a single-phase two-winding transformer without additional tap, given the possible connection group I / I-6 or I / I-0. Connection groups can be considered individually for each half of the secondary winding in case of using of additional tap. Shows an example of embedding the transformer model in a more complex computer model of the electric traction DC motors excitation current stabilization system, which includes a computer model of a saturable reactor, thyristor rectifier, system of pulse-phase rectifier control and control loop with a proportional-integral current regulator and boost nonlinearity. Obtained during the simulation graphics excitation current in the field winding of collector traction motor and its reactive component show that the above system of stabilization of the current and its computer model of functional and successfully fulfill their functions: at the downturn of the armature current excitation current is maintained by the growth of the current make-up of excitation control rectifier. The correct operation and ease of use of the developed computer model of a single-phase transformer with an additional tap at the middle point of the secondary winding is stated.

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.