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Investigation of instantaneous and average velocities of train movement, their properties and their application, including calculation of speed coefficients and movement time. Determination of influence of the movement speed and its restrictions, stops and delays onto travel time losses and traction energy consumptions of loaded and empty trains. Time and energy saving estimation due to the application of regenerative braking on the electric locomotive. Development of the recommendations for increasing average speed, decreasing travel time and energy consumption of freight trains.

The aim of the work is to study and evaluate the energy efficiency of regenerative braking of an electric locomotive when a freight train is moving at an unsteady and steady speed, to determine the degree of influence on the return of electricity of various factors, first of all, the mass of the train, the speed of movement, resistance to movement, the steepness of the slope of the track profile, driving conditions, the efficiency of traction motors and the needs of an electric locomotive own needs. Also, the purpose of the study is to develop recommendations for improving the energy efficiency of regenerative braking of an electric freight locomotive. Methods used: mathematical analysis, methods of traction calculations and energy balance. The equations of the energy balance of the movement of a freight train and its components in the mode of regenerative braking are considered, which make it possible to identify the main factors affecting the return of electricity at unsteady and steady speed. The calculated dependences of the return of electricity during regenerative braking of an electric locomotive with loaded and empty freight trains consisting of 71 four-axle cars, when moving with reduced speed and constant speed on sections of track with slopes of different steepness, characterizing the influence of individual factors on the return of electricity during regenerative braking of an electric locomotive, are obtained. It is shown that the specific return of electricity during regenerative braking of an electric locomotive with a loaded freight train weighing 7100 tons when moving with a decrease in speed on a track section with a zero profile is approximately the same as with a steady speed of movement on descents with a steepness of 6 ...7 ‰. The specific return of electricity during regenerative braking of an electric locomotive with an empty freight train weighing 1775 tons when moving with a decrease in speed on a track section with a zero profile is approximately the same as with a steady speed on descents with a steepness of 11 ‰ or more. The conditions under which the maximum return of electricity is achieved during regenerative braking of electric freight locomotives are determined. Recommendations have been developed to improve the energy efficiency of regenerative braking of electric freight locomotives.

The results of mathematical modeling of the heating process of the wheel material during braking mode of the locomotive are presented in article. The results can be used to calculate the temperature change for any point of the wheel during the braking operation.

The purpose of the work is to assess the energy efficiency of recuperative braking of a passenger DC electric locomotive when a train is moving at an unsteady and steady speed, to determine the degree of influence of the speed of movement and electric heating of passenger cars on the return of electricity during recuperative braking of an electric locomotive, to develop recommendations for improving the energy efficiency of passenger DC electric locomotives. The following methods were used: comparative analysis, methods of traction calculations, linear regression analysis, energy balance method. The equations of the energy balance of the movement of a passenger train and its components are considered in the mode of regenerative braking, allowing to identify the main factors affecting the return of electricity. The dependences of the return of electricity during regenerative braking, allowing to evaluate the influence of the train running mode and electric heating of passenger cars on the return of electricity during regenerative braking of an electric locomotive, are obtained. Developed recommendations to reduce the energy consumption of passenger trains. The conditions under which it is possible to increase the return of electricity during regenerative braking of passenger electric locomotives are determined. The developed proposals will allow increasing the energy efficiency of passenger DC electric locomotives.

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 article describes the general principles of the computational model of the traction power supply DC Railway to assess the potential energy recuperative braking, as well as ways of approbation the resulting model to determine its adequacy.

A method to an assessment of influence on the expenditure of electrical energy for traction of trains, parameters of graphic time-table in the conditions of using the regenerative braking is being considered in the article. The retrieval of version with the minimal using of energy is based on the modeling of graphic time-table by different train-to-train intervals in the conditions of burst-mode access’ organization on the railway section. By results of modeling it is proposed to represent the derived dependence by changing of electrical energy’s expenditure on parameters of graphic time-table in the form of analytic function of several variables n-order forthe following using by normative plotting of movement for the purpose of curtailing electrical energy’s expenditure for traction on the trains.

The article analyzes the components of the energy efficiency of regenerative braking and the factors influencing the effectiveness of the use of regenerative braking and energy recovery. Methods of evaluating the energy efficiency of recovery and the results of experimental studies of the effectiveness of recovery. Achieved justification for the use of the method of simulation modeling as a method for evaluating the potential of regenerative braking. It shows the sequence of the work.

The article discusses a question, which is bonded with the traffic safety, namely the integrity’s verification of the braking highway’s of the freight train before the departure. There was given a range of reports in the absence of the braking highway’s integrity’s test by the locomotive crews. There was the verification’s order developed and his testing done. There were made the suggestions for improvement of the safety devices in terms of automation of the integrity’s verification of the braking highway.

The article is devoted to the experimental study of the force interaction of the working elements of a disc brake in order to establish the dependence of the coefficient of static friction, taken as a criterion for the potential frictional properties of the friction unit, on the pressing force of the brake linings to the brake disc and the coefficient of mutual overlap. The experiments were performed on a full-scale stand, the basis of which is an electric drive with a power of 75.0 kW and a full-scale disc brake of the LT-10 tram. The stand allows to measure the static friction force under conditions of real forces, pressures, geometry of the contact area, as well as the coefficient of mutual overlap. TR119 and UT22-B were taken as friction materials for brake linings, in the first of which, according to the characteristics declared by the manufacturer, the coefficient of friction decreases with increasing temperature, in the second it increases. During the experiments, these materials worked in a pair of friction with the material steel 35, from which the brake disc is made. The experimental results were processed using the methods of mathematical statistics and presented in graphical form. It is shown that in the range of loads realized during braking, the stress-strain state of the contact area of the working elements of the disc brake according to the criterion of microstrains corresponds to an unsaturated elastic contact. This type of contact is typical for the studied overlap coefficients (0,33; 0,66; 0,98). It was found that with an increase in the pressing force of the brake linings to the brake disc, the static friction coefficient tends to decrease, and with an increase in the overlap coefficient, an increase in the static friction coefficient is observed for all specified values of the pressing force. At the same time, the UT22-V material is characterized by lower values of the coefficient of static friction compared to the TR119 material. Field of application of the results: development and design of advanced designs of disc brakes.

The article discusses a problem of the efficiency of the regenerative braking’s increase on the DC railway section. For the detection of the causes of the decrease of the specific regeneration’s level on the area an algorithm is offered, which enables to determine the causes of the decrease of the specific regeneration’s level on the arbitrary monitoring’s area in view of the determination of the locomotive’s capacity for work, work parameters of the electric traction system and the executed graphic time-table. In the article the main phases of the algorithm’s work were considered by the example of the one of the railway sections.

In this article, the currently existing methods for determining such a technical parameter as the sliding friction coefficient were considered. The coefficient of friction is one of the main parameters characterizing the operation of tribological pairs of any engineering system. Stable and efficient operation of tribological pairs in such systems, along with high strength and fatigue characteristics, are not only the basis of safety, but also a promising direction in terms of economic benefits in the design and operation of various devices and systems. Accordingly, this area of research is very relevant for the railway industry, and for railway rolling stock in particular. This is caused by a large number of friction pairs in different nodes of passenger and freight cars, locomotives, ensuring safe and uninterrupted movement of rolling stock as a whole on iron drogs. Tribological processes are important both directly during movement and during braking processes. In this matter, the factor of determining and analyzing the sliding friction coefficient comes to the fore. One of these friction pairs is the «pad-wheel» system, which is the executive body of the braking system of a railway train. Optimization of contact in this system is one of the determining factors for the growth of braking efficiency during braking, increasing the working life of the elements of the friction pair, reducing the likelihood of defects. The search for new approaches to the study of friction issues is a direct catalyst for scientific and technological progress in the engineering industry.

In article the design of an automatic pneumatic brake of the car with the braking accelerator is offered. Use of the developed accelerator of braking of an automatic pneumatic brake by freight cars allows to reduce a brake way of the train and to reduce longitudinally dynamic forces in the train when braking.

The article is devoted to the problem of elimination of thermomechanical damage on the surface of rolling wheel pairs of cars, which arising from the use of brake shoes to reduce their speed. A new design of the brake shoe equipped with electromagnets, which provides braking without jamming the wheel pair. Article contains calculation of the braking force and the provide slowdown .