Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan

About: Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan is a education organization based out in Dnipro, Ukraine. It is known for research contribution in the topics: Track (rail transport) & Bogie. The organization has 736 authors who have published 655 publications receiving 1468 citations. The organization is also known as: Institute of Railway Transport Engineers.

Model of Propagation of Traction Current Harmonics from Trains to a Track Circuit Receiver

Abstract: The problem considered in the work is related to ensuring the electromagnetic compatibility of new types of rolling stock with track circuits. The article presents a mathematical model for propagation of traction current harmonics in asymmetric rail line from multiple rolling stock units to a track circuit receiver. To simulate the distribution of return traction current harmonics in longitudinally inhomogeneous and asymmetric rail lines, a large number of parameters are required that characterize a specific design of a traction network and track circuits, which makes the task difficult for practical implementation. The mathematical model proposed in this work can be conditionally divided into three parts. In the first part, the distribution of the total traction current harmonic in both rails from all rolling stock units located in a feeder zone is determined without considering rails asymmetry. In the second, the distribution of traction current harmonics in rails, considering their electrical asymmetry, is determined for the problem track section. And in the third part, the propagation of the traction current harmonics from the rails to the track circuit receiver is investigated. The adequacy of the developed model was verified by comparing the results of calculations and measurements

Increase the resource of current collector elements of the electrified high-speed transport in operating conditions

Abstract: Purpose. The paper is aimed to determinate the main ways of increasing resource efficiency and exploitation of coal current collector surface inserts of speed electric rolling stock. Methodology. The research is based on the technique relies on the use of theory regulations of technical systems reliability, electromechanical processes, theory of statistics. Findings. The existing approaches to the production of current collector surface inserts in Europe and Ukraine were considered, a number of information sources was analyzed. The most effective ways of increasing current carrying capacity and wear resistance of current collector elements were determined. It has been established that the existing system for determining the quality of manufacturing of current collector elements have a number of drawbacks that make it difficult to control the input and makes diagnosing current collecting elements in operation impossible. On the basis of the facts, for the needs of the locomotive depot, we propose a new booth allowing avoiding the existing difficulties with diagnosing of current collector elements. During the study were established pervasive transgressions of technological standards of service pantographs. Originality. Based on the results of operational research carried out on the basis of the locomotive depot, obtained depending, based on which, it is proposed to introduce an operative diagnosing system of the current collector elements state during operation. In the course of a comparative analysis of existing and perspective development directions of current collector elements with high load current carrying capacity and durability, were definited constructive conditions for the optimal ratio is inserts. It was established that a significant proportion of failures occur due to imperfect maintenance system for which, on the basis of operational data, recommendations were developed. Practical value. Obtained results of the information sources analysis determine the need to implement coal inserts copper component in material, which will increase the load current carrying capacity of the current collectors. The numerous shortcomings of existing diagnostic systems carbon of current collector inserts skids pantographs were established, the solution of them should be the basis for the development of new means and diagnostic systems of current collector elements. It can improve service life of inserts and arrange culling of substandard of current collector inserts. The imperfect system maintenance of pantographs was established. The requirements increasing to this system will significantly reduce the amount of breakages caused by an increased transitive resistance in the «insert – pantograph».

Proposals for improving the process of forming programs of reforming the railway transport industry

Abstract: Purpose. The purpose of the work is to develop proposals for improving the process of forming measures and programs for reforming the railway transport industry of Ukraine in the process of European integration based on research, comparison and generalization of information. Methodology. A study of the content and the main provisions of legal acts declaring the conditions for the reform of the railway transport was carried out using analysis and synthesis methods. Methods of the system approach, comparison and generalization of the obtained data allowed developing proposals for improving the process of the formation of activities and programs. Findings. The need for reforming Ukraine's railway transport has been under consideration since 2006, but for a long time reform was limited only to the development of reforming plans and programs. Not being implemented within the framework of one program, the measures were reflected in the next or parallel one, with the corresponding change in the terms. The carried out analysis of their implementation does not allow talking about inactivity or denying the existence of positive changes, however, given the duration of the period 2006-2017, they occur very slowly. This situation requires new approaches to the development of programs and activities, as well as assessing their implementation, one of which is proposed in the work. Originality. The work justifies the need to evaluate the implementation of measures and programs for reforming the railway transport industry by two criteria: legal and practical. The developed basic principles for the formation of programs for reforming and developing the railway transport industry provide an opportunity to receive timely and reliable information on the status of their implementation. Practical value. We obtained the possibilities of constant monitoring of the state of financial support for reforms and directions of use of funds, which will prevent their misuse and significantly accelerate the implementation of certain activities, and then increase their effectiveness.

Definition of energy saving acceleration modes of trains

Abstract: Purpose. In modern conditions of rolling stock operation, the actual vital task is the increasing the efficiency of its use by reducing the cost of energy, including for the traction. It can be achieved by the way of locomotives power control systems creating, in particular the use of operating cards and on-board software and hardware. Methodo - logy. The article discusses ways of starting and acceleration of the train. Traction calculations with the definition of energy-efficient trajectories provide the search of a rational consumption of energy with time of running trains. When selecting energy saving train trajectories and the development of operating trains of reference cards, it is necessary to consider the variables such as: the profile area, weight of the stock, series of the locomotive and others. When the transmission power from the primary power equipment to the driving wheel pairs the inevitable losses that are described by the efficiency factor occur. For the most part of the locomotive elements the dependences of the efficiency factor are described by the nonlinear equations. Getting the energy-saving function of traction control at starting and acceleration to reduce the specific consumption of energy by improving the algorithm for calculating the trajectories of multiple trains was considered. The method of selection of energy-efficient trajectories at dispersal trains and power control electric and diesel locomotives with electric transmission which bases on the mathematical methods for evenly search and parametric optimization was offered. Findings. For the variables of the train situation and rolling stock was built two-parameter functional dependence of the power control locomotive and analytically determined the effectiveness of the proposed algorithm. Originality. In the work result the authors received the power saving function of traction control, which depends on the mass of the rolling stock and slant. In contrast to existing development of rational management of trains, this function requires much less computer time with a high accuracy of the calculations, which makes it possible to incorporate it into the onboard control system of the locomotive and energy savings. Practical value. Experimentally established algorithm, which is part of the on-board software package definition of energy-saving modes of conducting trains, will contribute to the reduction of energy expenses.

The Mathematical Support of Machine Surfacing for the Railway Track

Abstract: The condition of a railway track is characterized by many indices, including its geometric shape, both in the horizontal and vertical planes. The purpose of this paper is to create a mathematical tool to ensure the operation of track machines for surfacing, tamping, and alignment, which are equipped with automation systems. The developed mathematical model will be integrated into the AS "Strela" software package which is currently installed on machines. Scientific approaches used in the mathematical model allowed to reduce the operation of machines in "window", to simplify the work of maintenance personnel, to create an information base of track parameters, to establish rational parameters of curves during surfacing.