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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.

In this article the problems of efficiency of functioning of production systems of the locomotive repair enterprise are solved. In particular, the object of research is the technological processes of repair and maintenance of electric locomotives at the enterprises for repair of traction rolling stock. The article presents a mathematical description of the production process of such enterprises, on the example of the service locomotive depot «Moskovka». The mathematical model is described on the basis of queueing theory (QS) and Markov chains. A graph of the technological state of the locomotive during repair in the depot, where the process of transition of the repaired rolling stock from the state to the state, i.e. the relationship of technological movements of the electric locomotive on the territory of the depot, as well as the time of technological operations described transition matrix. The distribution of repair requests is described by the Poisson law, the delay of the electric locomotive in the depot areas in the planned types of repair in accordance with the accepted norm, and in the unplanned form of repair, the applications are delayed in accordance with the distribution of erlang. Based on the results of the mathematical description of the model of the production process of the repair enterprise, a simulation model of the operation of the Moskovka depot was created, implemented on a computer with the help of professional software of a new generation - AnyLogic. The paper describes the logic diagram of the simulation model, selected methods and modeling libraries. According to the results of the study, the overall assessment of technological performance indicators of the locomotive repair enterprise, in the conditions of probabilistic, dynamic changes in the repair task. By means of the methods of research of technological processes of depot «Moskovka» realized in article, it is possible to design any repair enterprises on repair of a rolling stock of the railroads, for the purpose of identification of «bottlenecks» of production process.

The article discusses the approach to generalized evaluation of technical condition of the diesel locomotive power plant functional subsystems based on the reduction of private parameters extracted by results of the analysis graph model to one-dimensional time function with use of mathematical expression of a nonlinear medium. Results of generalized evaluation of technical condition of the power plant fuel system are presents.

A variant of application of a contact compensated chain suspension with levers and lateral current collection for a three-phase traction power supply system (TSTE) is considered. Two different-phase contact suspensions are located on different sides of the track axis. The electric rolling stock must have two current collectors that press on the contact wire from the track axis in opposite directions. The description of the design of the contact suspension as a whole and the main components, in particular, the fastening of the rods, which makes it possible to provide a vertical zigzag and limit the transverse movement of the contact wire, is made. At points at the supports, the levers are connected to the consoles and have a knot to create angular rigidity. In addition, the rotation of these levers is limited towards the axis of the path and in the opposite direction. This prevents the possibility of lashing of different-phase contact wires. In accordance with this design, a mathematical model of this contact suspension was developed based on the finite element method, which provides calculation in statics and dynamics, taking into account the current collector. To describe the pantograph, a common three-mass model is used. Based on the analysis of the results obtained using this model, the influence of the design parameters of the suspension, cross wind and the speed of the pantograph movement on the quality of the current collection is determined, the limits of applicability of the suspension under consideration, depending on the value of these parameters, are established. It has been determined that, in contrast to a conventional contact suspension with a vertical current collection, for suspensions with a lateral current collection, a side wind has a significant effect on the quality of the current collection. It is the wind speed that is the main factor limiting the possibility of using a suspension with lateral current collection.

The article discusses the approach to evaluation of technical condition of the diesel locomotive power plant fuel system as a part of an integrated microprocessor control systems. Presents an approach of generalized evaluation of technical condition of the power plant fuel system. By results of the analysis of a fuel system graph model set of control parameters is selected, the algorithm allowing to establish the reasons of controlled parameters output of admissible limits is developed.

The article discusses the approach to operational evaluation of technical condition of the diesel locomotive power plant functional subsystems as a part of an integrated microprocessor control systems. Presents an approach to operational evaluation of technical condition of a fuel system. By results of the analysis of a fuel system graph model set of control parameters is selected, the algorithm allowing to establish the reasons of controlled parameters output of admissible limits is developed.

The article presents a method of calculation of the thermal state of the pantograph head. The density of the suspension zigzag distribution, taking into account a number of assumptions, has replaced the contact wire position function in the plan. Results of calculating the temperature of the pantograph head at different width of the zigzag of the typical suspension, including zero, are presented. The influence of sinusoidal and tangential contact suspensions on the temperature distribution of the pantograph head is estimated.

The results of infrared studies of the process of heating parts collector and brush assembly dc electrical machines. Proved diagnostic parameters for assessing the technical condition of the collector-brush assembly of electric motors: the ratio of changes in the elevation of temperature in time and space.

The aim of the work, the results of which are presented in this article, is to identify effective parameter of the heating process in the collector-brush unit of DC traction motor. The article suggests a detailed equivalent thermal equation of DC traction collector-brush unit. An experiment in a laboratory according to the theory of experimental design in the central rotatable terms of the second order are held, and the analysis of the results are presented. A method for processing the results of thermographic study of the machine is described. The regression equation, reflecting the degree of influence of the mode parameters of the machine on the intensity of the heating area of traction motor collector-brush unit, is compiled. The correct use of mathematical apparatus is confirmed by quantitative calculations Student's criteria assessing the significance of the coefficients of equations and F-Fisher criterion within the 5 % significance level. The results can be used to supplement the methods of DC traction motors and collector-brush unit technical condition diagnostics.

In article advanced techniques of laboratory and natural aerodynamic researches of a pantograph and its elements are considered. It is specified that carrying out modeling by means of computational fluid dynamics methods doesn't allow to replace pilot studies completely now. Need of correction of the received results because of influence of change of density of the environment during experimental studies locates. Density of the environment is offered to consider it as an integrated indicator. The main methods of measurement of density of the environment are given, their advantages and shortcomings are listed. The conclusion is drawn that it is most expedient to use ultrasonic measuring instruments to control of an indicator of density. The principle of operation of these measuring instruments is described. The example of use of an advanced technique of laboratory researches of the aerodynamic device for regulation of force of contact pressing of a current collector is given. Researches were conducted for device wing angles of rotation from zero to fifteen degrees with an interval of five degrees. After that aerodynamic characteristics of a wing of the aerodynamic device were under construction and comparison to results of modeling was carried out by means of a computing hydraulic gas dynamics them. The results received in OSTU laboratory well were correlated with results of computational fluid dynamics modeling that testified to adequacy of the applied technique.

The subject of the study is the fuel utilization system of a diesel power plant as a diesel locomo-tive or other vehicle main lead, which is a complex technical system consisting of actual diesel in-ternal combustion engine, fuel lines and low pressure fuel processing and high pressure line includ-ing various elements of liquid fuels consumption dosing and control. The aim of our study was to analyze the system functioning, to determine the dynamic proper-ties and the nature of changes in the internal parameters of the system as a whole. To achieve the goal the system analysis methods were used. The processes of complex technical system operation were interpreted by means of the continuous linear stationary deterministic model of the list of others. For this particular model the body of mathematics developed on the basis of linear differential equations with constant coefficients is the most complete one. The chosen mathematical model was presented by us in the first stage in the form of a finite graph as a subgraph of obtained earlier generalized model which had both methodological and theoretical foundation. In accordance with the methodology of the systematic approach the graph model of the diesel power plant fuel utilization system operation was described in relation to major significant factors affecting the system parameters transformation dynamics. Given the complexity of the of fuel ignition and combustion mechanism located in the diesel engine cylinder, the use of the techniques of the modern automated control theory is adopted for numerical processes simulation with the system described in terms of the said theory. The criteria of efficiency, mechanical loads and thermal loads levels were chosen as the fuel utilization system internal state variables. Taking into account the Pareto principle the most important efficiency criterion components were chosen for the analysis; and the system of differential equations of the efficiency dynamics in the form of three balance equations was created. The factual description of the included equations allowed us to derive preliminary qualitative conclusions about the dynamic properties of the internal criteria: controllability, observability and stability of the fuel utilization system. The differential equations system parameters linearizing procedure and the introduction of small deviations allowed us to obtain the dynamic mathematical model of the fuel and air transfor-mation in the diesel engine heat cylinder. As the result of transformations we have obtained the equations presented in the form of the matrices, which allowed us to conclude that the process of the fuel and air transformation in the cylinder is controllable, the system is asymptotically stable, and the process is stochastic with the presence of perturbing parameters influenced by the engine's variable modes of operation. The further research areas have been suggested, and the practical results have been predicted: the creation of optimal (in terms of efficiency) control system with the technical solution in the form of the optimal controller (in relation to fuel consumption).

The article is devoted to the improvement of the testing method of current collectors of electric rolling stock considering collision efforts from the overhead catenary. The article discusses the features of collision effects on pantographs of electric rolling stock at high speeds. An analysis of the existing methods for testing collision effects on pantographs in laboratory installations and in linear conditions has been carried out. The analysis is carried out and the drawbacks of the percussion pendulum installation for testing current collectors, described in GOST 32204-2013, are identified, and its characteristics are calculated. The design of a shock stand with smaller dimensions and expanded functionality is proposed, and its parameters and characteristics are calculated. When calculating the characteristics of the test bench, mathematical and computer modeling was applied using the MATLAB Simulink environment. The method of bench collision testing using accelerometers and high-speed video camera. It was established that the proposed test bench retains the full functionality of the test facility regulated by GOST, while having smaller dimensions and wider functionality.

The article provides for the design features of pantographs of an electric drive train, a system of movable frames, which are made in the form of two articulated rod-type levers. Single-lever pantographs are distinguished by improved mass-dimensional indicators, which allows them to be used in the cramped conditions of the roof space of two-system electric locomotives. This requires high mechanical characteristics, as well as the need to use structural materials of increased strength, precision processing methods and high precision during assembly. It becomes especially important to control the transverse and advanced cruelty of the moving frame system during research, periodic and qualification tests, as well as during operation. The article describes a methodology that allows conducting research with a high degree of labor intensity, increasing the speed of measurements, and reducing the influence of the human factor.

The contact line is a special kind of power overhead line with multiple electrical connections of wires, which form a complex topology of the linear electrical circuit. Analytical models simplify the real topology of the contact line and it limits their functional application. It is possible to take into account the topology of contact line when using tools of computer simulation, but it entails complicating the computational algorithms of the model. The aim of this article is to determine the conditions for the application of current distribution models and the development prospects in this area. The article describes the existing models for calculating the current distribution in DC contact line: a model of natural current distribution, linear analytical models, model with an infinite number of droppers, a model with a direct application of Kirchhoff's circuit laws in matrix form, and a finite element model. The article contains the main provisions and calculation capabilities of each model. Contact line KS-250-3 acts as a calculation catenary for the comparison of current distribution models. You can use the results of the article to select the optimal design distribution model for the design of the contact line, thermal analysis, current-carrying capacity calculation, identification and elimination of «weak point».

In general, improvement of methods for electrical calculations aimed at increasing the accuracy of the results. One of the ways to improve the methods of calculation is the account in the calculation of the various factors that affect the accuracy of calculation of the traction power system parameters. This article describes an approach aimed at improving the method of calculation in the electrical part to improve the accuracy by changing the algorithm for calculating and accounting for a number of additional factors.

The article considers the processes of current collection in the system of AC electric traction in high-speed traffic. The existing devices of pantograph and catenary interacting by means of a sliding electrical contact are presented. The comparison of solutions with different horizontal geometry of the contact wire, which affects the speed of the lateral displacement of the contact wire at the catenary supports relative to the axis of the railway track, is given. It is shown that the speed at which the contact point moves along the pantograph strip is also important for assessing the wear of the sliding contact, as is the span length of the catenary supports, the curvature of the track and the speed of the train in the span limits. For the synthesis and analysis of the pair "pantograph strip - contact wire" with a sliding contact, a model for calculating the contact surface is obtained and the energy processes leading to wear of the components of the current collection system are considered. The results of modeling the interaction of the pantograph and the catenary with various variants of the zigzag arrangement of the contact wire are obtained. When implementing a technical solution in areas with high-speed traffic, the preferred method proposed in the article is the arrangement of the contact wire of a chain suspension with a zigzag period increased by two times compared to the traditional one. This solution provides a reduction in the speed of lateral displacement and increases the dynamic stability of the pantograph, reduces the cyclic load on the supporting and supporting structures of the catenary and increases the life of the contacting elements of the current collection system during high-speed traffic.

The article presents an improved mathematical model of the thermal state of the pantograph head for calculating the temperature distribution when interacting with different catenary with a double contact wire. The model takes into account the unevenness of the pantograph contact pressure on the wires along the suspension span and between them, allows using the databases of the car-laboratory for testing the contact network, calculating the thermal conditions of the skid on various sections of electrified Railways, including transients between them. The paper presents graphs of the zigzag distribution density of the contact wire of the Moscow - Saint Petersburg high-speed line, and defines the transient and steady state thermal states of the pantograph head when the pantograph interacts with them.

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 considers the current situation regarding the organization of control over the use of traction and energy resources of JSC «Russian Railways». The main provisions of the proposed method are stated. The influence factors on the specific electric power consumption of electric locomotives of series 2ES6 and VL10, as well as the evaluation of the quality of the constructed models of multiple nonlinear regression were estimated. New scientifically grounded technological solutions and developments are proposed that allow to reduce the specific consumption and unproductive losses of electric energy within the boundaries of the railway accounting areas.

The article describes the design of a universal measuring pantograph, designed to obtain during the test trips sets of accurate and adequate information on the quality of current collection due to the possibility of modeling parameters and characteristics of advanced domestic and foreign current collectors, mounted on a modern electric rolling stock. Presented the results of his testing at the West-Siberian railway.

A mathematical model of thermal processes (dynamic) contact current collector with contact suspension (in motion), which allows to estimate the temperature distribution of heating the current collector during movement. The experimental evaluation of the proposed cooling device performance is given. The thermal model of the current collector in motion mode has been verified.

The method of practical realization of decision of the special case of a transport task is examined. It allows to find optimal and the set amount of routes the nearest to it on the size of criterion of optimality. A method provides large flexibility in the decision of questions of planning of optimal organization of vehicular process at making, both strategic plans and operative plans in case of origin of situations of type "accident", "congestion", or other force-majeure circumstances.

The actual process of interaction of pantograph with catenary associated with random processes. The main factors affecting the pantograph are vibrations of the rolling stock, aerodynamic, the instability of the dynamic properties of the pantograph and overhead catenary, etc. In view of the plurality of influencing the current collection of factors theoretically investigate the dynamical system "Pantograph - catenary" in full It is a complex task. A more rational to theoretical studies and sufficient for practical use is to consider deterministic processes. In the numerical simulation of the current collectors are the most common types of the following design schemes (models): lumped mass pantograph model; pantograph multibody schematics; pantograph multibody schematics in CAD-systems, which describe in detail the geometric dimensions and physical properties of each element of the pantograph. In the design of the pantographs is an integral part of the calculation of interaction of pantograph with contact suspension. Contact suspension counted in the calculations in the form of a concentrated mass interacting with the pantograph skid or a spatial system composed of resilient elements of finite length (catenary with distributed parameters). The second type of catenary model is used in the interaction with the first two types of models considered by the current collectors. Based on the features of each of the presented kinds of models, present the technique of the pantograph model selection, depending on the purpose of the simulation.

Resistive heating of the pantograph head due to the flow of traction current through the conductive elements of the upper node, has an uneven distribution along the frame structure and depends on the location of the contact wire on the insert. The aim of the work is to develop a mathematical model for calculating power losses in the pantograph panhead, allowing to estimate its value, taking into account the zigzag of the contact wire during the movement of electric rolling stock. The subject of the study is the pantograph panhead. The paper gives an example of calculating the frame skid of a pantograph equipped with carbon strips. Experimental studies of the current distribution over the shunts of the panhead depending on the position of the contact wire were carried out in February 2021 in the laboratory "Designs of contact networks, power lines and current collection devices" using a complex for testing current collection devices. The calculation of the heating power of the panhead is determined by the Joule-Lenz law. The results of the calculation showed that the maximum heating power is observed when the contact wire is in the middle of the panhead, while the places of the greatest losses located along its edges are above the places where the shunts are attached. The model makes it possible to obtain a functional dependence of the heating value along the panhead. The obtained results of the skid heating power distribution make it possible to supplement the complex model of the thermal state of the pantograph developed at the Omsk State Transport University with the participation of the authors of the article. The versatility of the developed model makes it possible to investigate various zigzags of the contact wire and evaluate the effect on the distribution of traction current along the panhead, depending on the location of the shunts and their number.

The article presents the results of measurements of electricity on active and passive sectioning posts the traction power supply system direct current sections of railways with III and IV path profile type. Basic characteristics of operating modes sectioning posts for the purpose of assessing the amount of electricity transferred and duration of work electricity storage in different modes are considered. The most observed voltage values, volumes of transmitted energy and duration of each case are defined. Choice of theoretical distribution laws, allowing to use the experimental values obtained in further calculations in modeling of operating modes electricity storage is completed.