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The subject of the research is the power thyristor converter of AC electric locomotives and its influence on the power factor of the locomotive. A new method for increasing the power factor of AC electric locomotives with thyristors power converters is proposed and analyzed. These electric locomotives include locomotives of the 2ES5K, VL85, EP1 series, etc. At the initial of the paper, the existing methods of increasing the power factor are briefly considered and their disadvantage in comparison with the proposed method is indicated. The drawback of existing converters is also analyzed, which consists in the presence of a thyristor opening delay at the beginning of the supply voltage half-cycle. The proposed method implies the modernization of the control circuits of the thyristors of the converter, due to which, at the beginning of the half-period, a control current is spontaneously created on the control electrode by means of the supply voltage. As a result, the thyristors open with a minimum delay after the start of the half-cycle. To verification the effectiveness of the proposed solutions, a computer simulation of the operation of the power circuit of an electric locomotive in the ORCAD program was carried out. Simulation was carried out for two options: a power circuit with standard converters and a power circuit with converters upgraded in accordance with the proposed method. During the simulation, the change in the value of the power factor of an electric locomotive was investigated at different currents of traction motors, zone and angle of regulation. Analysis of the oscillograms of converter various arms currents the revealed that when using the modernized converters, the moment of the end of the network switching occurs earlier than in the standard circuit. There is also no area with negative voltage at the output of the converter at the beginning of the half-cycle. At the end of the paper, the values of the electric locomotive power factor are given under various conditions. These results show that the use of the proposed method increases the power factor of an electric locomotive by an average of 1.2 percentage points.

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.

The author considered the problem solving of control of the boiler hermeticity of railway tanks using contemporary control methods. The author described the activities and equipment which are necessary for assessment of technical state of large-volume vessels. The implementing algorithms of step-by-step operations for monitoring and analyzing the results processing are proposed. The proposed method of technical condition of the railway tanks boilers is based on the use of serial thermal imaging equipment, which allows to reduce the economic costs of monitoring and improve the working culture of the flaw inspector.

Abstact. During automated rheostat tests of locomotives itʹs necessary to control a lot of parameters of the diesel generator set and support systems. Due to the features of perception of the information by human the control is brought to the observation of a small number of parameters. Implementation in practice of rheostat tests of automated systems of inspection and testing allowed to expand the amount of received information. In this article is offered using automated control systems of diesel-generator sets parameters during rheostat tests which allow to accumulate and analyze test date using developed protocols forms and pivot tables with parameters in entire range of loads, also it helps to determine the quantitative index of a technical condition of diesel-generator set.

A modern solution to the problem of improving the efficiency of the traction rolling stock maintenance and repair processes based on the use of new information technologies is the transition to a locomotives predictive repair promising system. The key element of the predictive repair system in the issue of operational assessment and management of the locomotives technical condition are onboard microprocessor control systems with built-in diagnostic, monitoring and monitoring subsystems. The onboard microprocessor control systems have the ability to carry out continuous or discrete measurement, registration, transmission and accumulation the values of large package analog and discrete locomotive equipment parameters. The functionality of the onboard microprocessor control systems based on information technologies makes them an exceptionally effective means of efficiently organizing maintenance and repair impacts on the locomotive park in order to ensure specified operational reliability and performance indicators.

In article presented the mathematical model of fuel heating of the high pressure pipeline of diesel engines fuel equipment and calculation results of temperature of its external surface at various temperatures air and the fuel equipment technical conditions.

Considered the features of modern automatic control systems of pantographs. The spectral density analysis of pantograph contact force at high speeds showed requirements for robust control systems, which allows to significantly improve the quality of the current collection. Proposed the ways to improve the automatic control systems for pantographs, aimed at improving the speed and reducing the inertia of the system.

The subject of the article is automated locomotive control functions on the example of electric locomotives in order to assess the current stage of development of the intellectual functionality of on-board control systems. The literature often talks about creating a «smart» or «digital» locomotive. However, it is more correct to talk about the introduction of cybernetic systems with feedback. Such systems were on the locomotive from the very beginning of their appearance and were designed to automate steam control, later to control automatic brakes. These automation systems were mechanical and pneumomechanical. With the advent of electric locomotives, electrical automation systems based on electrical devices, relay circuits are being introduced, which are eventually replaced by diode, transistor control circuits. Later, digital and analog chips were used. The current stage of automation development is associated with on-board microprocessor control systems. The author proposes to divide the intellectual functions of the locomotive into seven directions, for each of which to evaluate their implementation: train driving, drive and brake control, diagnostics, collection of emergency circuits, ensuring train safety, managing the comfort of the locomotive crew. The entropy of the space of intelligent functions is proposed to be estimated according to the modified Shannon formula, where, in addition to the probability of the function being in demand for one trip, the degree of automation of the control process is taken into account. As a result of the analysis, it is shown that the intellectual functions of the locomotive developed already in the 19th century, today the degree of their implementation can be estimated at 60 %, and full implementation can be expected by the middle of the 21st century. The calculation results are summarized in two tables and one dynamic graph. It is concluded that an "intelligent" locomotive is a stage in the evolutionary development of automated locomotive control systems.

The paper describes a mathematical model of gas-dynamic movement through the through defects in the body of the boiler tank cars. The mathematical model allows to take into account the processes of gas flow at low pressure drop and the impact of the level of roughness of the inner surface of the through channel formation jet escaping gas. The comparison of the results of theoretical modeling and experimental studies of the velocity of the gas flow and temperature under different conditions. The study identified the laws of gas flow through a series of classic models through defects. Shows the dependence of the temperature of the escaping gas flow from the exhaust velocity and the level of roughness of the internal surface of the through channel, which allows us to estimate the nature of gas flow and temperature gradient. The obtained results allow to adjust the level of sensitivity to rejection temperature during thermal leakage control boilers railway tanks.

In the article the paper considers mathematical modeling of fuel equipment of high pressure and regulator of the rotation frequency of the crankshaft of the diesel engine. Analysis of factors affecting fuel equipment, mathematical modelling of the process of fuel into the cylinders, as well as mathematically describes the speed control of the crankshaft of the diesel diesel engine. Joint mathematical model of fuel equipment and rotation speed regulator. Presented algorithm and program calculation process the fuel feed to the cylinders of a diesel engine with a light hydraulic characteristics of generalized elements of fuel equipment and provision of the Executive mechanism of the regulator of the rotation frequency of the crankshaft of the diesel engine. In the work used mathematical and simulation, system analysis methods, the comparative method, methods of theoretical knowledge (formalisation), common logical methods and techniques of research (analysis, synthesis, classification, analogy ).

The article presents the results of experimental studies to assess the possibility of using thermal methods of controlling the leakage of the boiler of a railroad tank car. This paper reflects the research of formation of the thermal field on the outer surface of the tank in the area of end-to-end defect such as a crack, by throttling through the gas medium due to the pressure differential. Presented thermograms show the localization of the defect with a detailed description of the anomalies of the thermal fields, recorded by the imager. Also confirmed the experiments described in the work on Joule and Thomson for throttling gas through local obstacle.

The development of traction rolling stock is closely associated with an increase in the maximum traction force for adhesion the wheels to the rails. The negative factor in this aspect of development is slipping. The article proposes a new method of protection against slipping of wheel sets of electric locomotives 2(3)ES5K «Ermak». The method implies redistribution of tractive forces between wheel sets and minimization of sanding. The paper discusses the principle of operation of the anti-slip system and the principle circuit of the power section, and simulates some modes of wheel sets in the Multisim software package.

Modern locomotive on board microprocessor-based control systems (MSU) can be used for not only controlling locomotive equipment, but for analyzing the process of their functioning too by means of mathematical statistics. It is confirmed by authors of this article. Through the article is offered method of nearby-failure condition diagnostic by the means of MSU data correlation analysis.

The subjects of the study are the problem of controlling the crew in space by means of an automatic system for controlling the gap between the electromagnet poles and ferro-rails in the system of high-speed land transport based on the levitation effect. One of the main conditions for comfortable levitation mode of the crew is the absence of vertical deformations of the crew during multipoint suspension due to non-uniform distribution of lifting and guiding forces. In order to ensure the stability of the crew's electromagnetic suspension, various combinations of control system feedbacks are proposed. The results of the study of the electromagnetic suspension control system using the electromagnet current feedback in the land speed vehicle levitation mode are presented. The main requirement to the control system of an electromagnetic suspension in the levitation mode is the maximum permissible deviation of the permissible air gap ±5 mm under the action of the impulse of the aerodynamic force in the horizontal plane and the speed of its application. The principle of subordinate regulation of the control system parameters with the use of regulators in accordance with the functional two-loop system of automatic regulation with current feedback has been proposed. The application of the double-loop automatic control system at supply voltage fluctuations corrects the electromagnet current and excludes the deviation of the maximum permissible gap between the electromagnet and the ferro-rail. The performed calculations prove that the introduction of the electromagnet current feedback decreases the velocity transfer coefficients and thus increases the signal speed.

In this article, the authors have studied the electromagnetic processes of an inverter based on thyristors and IGBT transistors of an AC electric train in the regenerative braking mode. To accomplish this task, a method was used to compose instantaneous replacement schemes and systems of differential equations corresponding to a certain time interval of the rectified voltage diagram and the currents of the inverter arms. On the basis of the study were given the disadvantages of thyristor inverter and the advantages of transistor.

The work relates to the application of a new method of noncontact RFID monitoring of the condition of insulators for overhead power lines, including signaling, centralizing, blocking, and longitudinal power supply lines . A significant number of accidents occur due to the breakdown of insulators and imperfection of control methods. It is proposed to use a non-contact RFID control system for overhead power line insulators, which consists of a reader with a transceiver and an antenna, standard insulators with RFID indicators and special software. The aim of the research is the influence of climatic factors on the components and assembly structures of pin insulators with RFID indicators and the operation of the RFID control system in general. The selected study samples are a radio frequency tag, an aluminum-coated plastic cap with an integrated tag, and a pin-shaped porcelain insulator with an RFID indicator in the assembly. The climatic tests were carried out in the testing center of technical means of railway transport of the Ural State University of Railway Transport (IC TSZHT USUPS). Temperature changes were simulated from -60 to +50 ° С with air humidity up to 93%. The results on the adhesive properties and electrical conductivity of a conductive coating on a polyethylene surface and the stability of the functioning of RFID tags are presented and analyzed. Suggestions for improving the components and assembly design are given. Firstly, to use a screw thread on the top of the pin instead of a special knurling, which will reduce mechanical stress during installation of the structure of individual components and will reduce the error in the installation dimensions to improve the reception and transmission of signals between the reader and the tag. Secondly, sandblasting of the surface of the polyethylene cap can improve the adhesion of the surface to the conductive coating, which will increase the electrical conductivity of the structure. The result of this work proves that the developed RFID control system of insulators functions in the climatic conditions specified by GOST, which allows to recommend its implementation in the lines ts use in lines of devices with a voltage of 6-10 and 35 kV.

The article suggests that the reason for the increased wear of the tires of electric locomotives with an asynchronous traction drive is the increased sliding speed in the contact of the wheels with the rails. It is shown that in thrust modes with high sliding speeds, frictional self-oscillations can develop in the drive. The stability zones of the drive are constructed in the space of its parameters. The model of an asynchronous drive with a «jammed rotor» for the study of skidding modes has been substantiated. It is recommended to install a clutch control system (СCS) on the electric locomotive to reduce wear on wheels and rails. СCS intelligent sensors create an additional feedback channel for the system of optimal traction control - the implementation of maximum traction forces with minimal friction losses. The methods and recommendations presented in the article are applicable to various designs of traction drives.

In article stages realization of complex systems non-contact thermal control of the main knots and systems locomotives are considered. The developed techniques of an assessment technical conditions sections refrigerators, electrical machines and the fuel equipment of a high pressure locomotives with use thermovision control method are presented.

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 drawbacks of the step-by-step automatic voltage control system under load AVC and the non-contact automatic voltage control system NAVC with the reactor switching device of the converter transformer used in the traction power supply are analyzed. The scheme of a thyristor-reactor switching device (TRSD) connected to the primary winding of the transformer is considered. A brief description of the operation of a transformer with TRSD and the procedure for calculating the symmetrical and asymmetrical external natural characteristics of a converter unit with TRSD are given. Based on the dependence of the energy indicators of the converter unit on the resistance of the uncontrolled reactor TRSD, a method is proposed for calculating the rational resistance of an uncontrolled reactor, where the power factor of the converter unit is taken as the criterion of rationality. The method includes two stages: the first is the calculation of the values of the power factor of the converter unit depending on the resistance of the uncontrolled reactor and the load current of the converter unit; the second is the determination of the average load current value of the power factor of the converter unit for each considered value of the resistance of the uncontrolled TRSD reactor and the determination of the rational for the considered external natural characteristics of the unit. In accordance with the presented methodology, the calculation of the minimum permissible and rational resistances of the uncontrolled reactor TRSD as part of a converter unit with a converter transformer TRDP-16000/10 was made. Taking into account the selected rational value of the resistance of the uncontrolled reactor TRSD, a calculation was made and the external natural characteristics of a converter unit with a TRSD and a converter transformer TRDP-16000/10 are presented. The performance check of the presented calculation method for solving the problem of choosing the rational resistance of an uncontrolled reactor was carried out on a physical model of a converter unit with a TRSD, with a 12-pulse rectifier unit, with a 30 kVA transformer and a linear primary voltage of 380 V. Comparison of experimental and calculated values showed a slight discrepancy, the permissible error was not exceeded. Determination of the resistance value of an uncontrolled reactor based on the developed methodology provides the highest values of the power factor of the converter unit.

The article presents the results of the research conducted by the authors, the purpose of which was to development a model for recognizing defects in axle caps of a wheel-motor block of a locomotive in order to implement automatic advance notification of management structures about the need for maintenance or repair operations to eliminate defects at an early stage of their occurrence. The research used the following interdisciplinary and mathematical methods: computer and mathematical modeling, methods of mathematical statistics, methods of the theory of artificial intelligence and parametric reliability. As a result of the research, a mathematical formalization of the model for recognizing one of the defects in the axle caps of the wheel-motor block of the locomotive - the groove (chipping) of the babbitt layer was obtained. With the help of the obtained model, it is possible to implement automatic recognition of defects, pre-failure states not only of axle caps, but also of other units of technical systems. The developed model can be used in monitoring systems, control, diagnostics of the technical condition of the locomotive fleet, in order to reduce downtime in repairs and forced costs for scheduled operations. The proposed model solves the range of problems described in the development concept of JSCo Russian Railways associated with the implementation of the actual repair system for the current technical condition of the locomotive, as well as with the digitalization of the company's advanced areas.

In clause the organization and perfection of process of repair axle box units of a rolling stock by results of diagnostics is considered. The diagnostic model of object, and also a technique of perfection of repair on an actual condition with application of technical diagnostics and the analytical means, based on concept ТРМ is resulted.

The article is devoted to the description of the requirements for the accuracy of control devices and the development of methods to ensure the claimed dimensional accuracy by methods of dimensional analysis. The conditions for ensuring the accuracy of the assembly scheme, the determination of the dimensional chain and dimensional analysis of the dimensional chain during the assembly of the control device, as well as the main causes of errors during assembly and ways to eliminate them are listed. In addition, the consequences of the influence of irregular gaps in the interfaces of the control device parts on the measurement accuracy are presented, various types of assembly dimensional chains are considered, tasks solved when calculating the dimensional chain. The paper presents a compiled dimensional chain of the technological process of assembling a measuring instrument for monitoring the alignment of the inserts of motor-axial bearings of traction electric motors of locomotives, which represents a dimensional chain of the first type and is a chain with linear dimensions and vertically parallel links. The purpose of the work is to substantiate the calculated tolerances and limit deviations of the links of the assembly dimensional chain, providing the required value of the closing link for the proper functioning of the assembled measuring instrument. The paper describes the selection of the closing link of the dimensional chain, the selection of the links that make up the dimensional chain, the calculation of the limiting deviations of the closing link that ensure the required measurement accuracy during operation of the control device and the calculation of the limiting deviations of the components of the links of the dimensional chain by the "maximum-minimum" method. Thus, the article presents a solution to the design problem of dimensional analysis, which consists in determining the accuracy of the component links of the dimensional chain when assembling the control device according to the known calculated tolerance of the closing link and its limit deviations.

In the article suggests a changing the algorithm of the rectifier-inverter converter electric locomotive VL85. This will allow the individuallyto regulatevoltageon traction engines. In this case willpreserve a singlecentralized system ofcontrol of allelectricconverters. The proposed solutions may be used for liquidation started spinning of wheel locomotive. Tractive force the remaining wheelsets will not decrease.

The article presents the main requirements for the development of traction motors commutation control digital device and the results of the development and testing of this device on the test bench. Justified the expediency of application of the input highpass filter when the power of the testing traction engine from the thyristor converter. Presented the technique of processing the diagnostic signal from bipolar brushes to filter out noise of different physical nature.