Purpose. Improving the efficiency of passenger traffic on non-electrified sections of the railway of Ukraine by optimizing the structure and creating principles for building a traction electric drive of a promising autonomous electric train powered by traction engines from the system of onboard storage of electricity. Methods. The methodological basis of the study are the general theoretical provisions and principles of the system approach of theoretical electrical engineering, theoretical mechanics, theory of electrical machines and converters. The basic principles of management theory and the basics of decision theory are used. Results. The general principles of construction of the traction electric drive of the perspective autonomous electric train with power supply of traction engines from onboard energy storage devices are formulated. The functional scheme of the traction electric drive of the perspective autonomous electric train is offered, the analysis of work of the electric drive in the modes of traction and regenerative braking is carried out. The mass parameters of two types of energy storage devices, namely electrochemical batteries and supercapacitors, have been determined. The basic requirements to the system of automatic control of the traction drive of the electric train are formulated. It is shown that in the future the use of autonomous battery electric trains will be technically possible and economically justified on non-electrified sections of Ukrzaliznytsia.
Purpose. The actual state of many of the existing testing stations for traction electric machines does not meet modern requirements for the organization of repair and technical control. At most of these stations, mutual loading stands with low energy efficiency are used. The purpose of the work is to determine the rational mode of loading electric traction machines, which will ensure a decrease in the total power of the power sources of the test station, an increase in energy efficiency and the quality of tests. Methodology. The methodological basis of the work is the general theoretical provisions and principles of the systematic approach of theoretical electrical engineering, theoretical mechanics, the theory of electric machines and converters. The substantiation of the energy and electromechanical principles of mutual loading of traction electric machines is performed using the basics of generalization and systematization of physical quantities and concepts, the theory of electric circuits, the theory of mechanical systems, and the theory of electric machines. The analysis of thermal processes and energy parameters of the electric machine test system was performed using the theory of heating a homogeneous solid body and known methods of calculating thermal circuits. The results of theoretical studies have been confirmed experimentally. Findings. The analysis of the expression for determining the energy efficiency coefficient of heating the windings of traction electric machines, obtained in the work, shows that the starting current is the most rational when testing the traction motors of electric rolling stock of mainline transport for heating. The use of this load current allows reducing the electricity consumption for tests by 20-30% (compared to the hourly mode) without reducing the quality of tests, as well as reduces the time of heating tests by three to four times. Originality. The expediency of conducting the heating tests of traction motors of main electric rolling stock with a load current equal to the current of the start-up mode has been scientifically substantiated, which ensures the energy efficiency increase of the tests and a corresponding reduction in the total cost of electricity for acceptance tests. The method of analytical determination of the weighting coefficients of influence on the temperature excess of the armature winding of electric losses was proposed, the use of which allows evaluating the influence of the mutual loading modes of the tested traction electric machines on the discrepancy degree of the thermal loads of their armature windings. Practical value. The results of theoretical studies allow determining the rational modes of mutual loading of traction electric machines, which make it possible to reduce the electricity consumption for conducting their heating tests and shorten the time of conducting heating tests. In addition, it becomes possible to propose a method of evaluating the quality of acceptance tests of traction electric machines, which takes into account the discrepancy degree in the thermal loads of the windings.
Purpose. The safety of the transportation process in railway transport and its continuous operation to a large extent depend on the reliability of the means of railway automation and communication. In this case, special role in ensuring the efficient and safe operation of railways belongs to the systems of interval control of the train movement, as well as automatic locomotive signaling in conjunction with the systems of monitoring the driver's vigilance and automatic train stop. Therefore, the main purpose of the article is a detailed analysis of the operation reliability of these systems, in order to be able to correct service techniques and improve operational work, based on the information received. Methodology. To prevent halting and failures in the operation of automatic locomotive signaling devices, it was analyzed the failure statistics of all devices of railway automatics, which can lead to disturbances in its work. It was identified the most responsible devices, whose control will greatly affect the system performance and increase the reliability of the work as a whole. Findings. Analysis of statistical data showed that the main causes of malfunctions in the automatic locomotive signaling system are the failure of the decoder, locomotive filter and amplifier, and the main reason for the malfunction is equipment wear. Originality. The results of the work aimed at increasing the efficiency and reliability of the operation of the railway equipment are continuously implemented in the operational work, automating a large number of technological processes and improving the failure rate performance. However, ignoring this, the analysis of the operation of devices on the railways for the period 2013–2017 showed that a significant part of the reasons for the deterioration of the reliability of all systems of railway automation and separately considered locomotive alarm system accrue to the human factor, embodied in violations of the technology of work and non-compliance with the requirements of technological maps and manuals, as well as poor repair and inspection of devices in repair and technological areas. Practical value. The analysis showed that the issue of improving both the systems themselves and the devices of railway automatics, as well as the methods of their inspection, operation and maintenance, will increase the level of safety and reliability of transportations.
Purpose. Given the need to improve the performance of modern mainline rolling stock, the authors analyze the possibility of using deeper regulation of attenuation. Methodology. The analysis of the operation of the thyristor-pulse converter of ER200 electric train is performed. It is established that in the acceleration mode at the limit traction characteristic it is necessary to consider two zones: the zone of constant value of traction force and the zone of constant power. A method for determining the minimum value of the attenuation coefficient for different types of DC and PC traction motors was proposed. The methods of theoretical research and analytical calculation of electrical circuits, theoretical foundations of electric traction, mathematical modeling of electrical and energy processes were used for the analysis. Findings. The complex of theoretical research and calculations allows confirming the technical possibility of deep attenuation use to regulate the speed regulation and obtain additional across-the-line positions for the rolling stock with DC and PC traction motors. The minimum attenuation coefficient value for different types of traction motors was determined. Originality. The methodology for determining the minimum value of the attenuation coefficient for traction motors of main electric locomotives in terms of using deeper magnetic flux control, replacing the use of experimental research data with theoretical studies. The essence of the studies is to form the required type of the limit traction characteristics by reducing the minimum permissible value of the excitation coefficient, which will reduce the electricity consumption. The research on determination of quantitative indicators of electricity consumption for the analysis of energy saving reserves on the main transport was further developed. Practical value. The results of theoretical research can be the basis for the modernization of main electric locomotives of direct and pulsating current with the systems of deep attenuation regulation. The research conducted will make it possible to create recommendations on designing the systems of magnetic flux regulation for traction engines with the improved technical and economic characteristics which are capable to increase the transport process efficiency on the main transport.
Purpose. Increasing the operational indicators of suburban transportation on railways electrified by alternating current due to the modernization of traction static converters of ER9M electric trains. Methodology. The methodological basis of the study is the general theoretical provisions and principles of the system approach of theoretical electrical engineering, the theory of power converters. The main principles of construction of traction static converters of electric rolling stock of railways are used. Findings. The analysis of the basic rectification schemes of alternating current electric trains was performed. As an alternative scheme, it is proposed to introduce a controlled rectification scheme based on a four-zone rectification scheme, which is similar to electric locomotives, which allows using most of the known advantages of non-contact traction electric drive control systems. Some energy figures are calculated for the fully controlled and semi-controlled circuit. As a result of the comparison, the modernization option based on a semi-controlled rectification scheme was selected. The required values of starting power of the transformer and power factors for schemes with uncontrolled, fully controlled and semi-controlled rectifiers are determined. A selection of modern semiconductor elements is offered for the configuration of converters. It was shown that in the case of modernization of the rectifier scheme, there is no need for significant capital investments due to the preservation of the main traction transformer and traction motors of the electric train. Practical value. The obtained results can be used by enterprises that carry out major repairs of alternating current electric trains.
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