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In the article the possibilities of improving the adjustment properties and technical characteristics of electric rolling stock with collector traction motors are considered. Semiconductor devices can improve the smoothness of the traction motors start-up due to a more even voltage increase, smooth regulation of the field current in the traction and braking modes. Variants of simplified power circuits of eight-axis direct current electric locomotives with a minimum number of switching electrical devices have been developed, allowing to reduce weight and size of the equipment, increase the reliability of power circuits operations. Circuit solutions for protecting the wheelset of an electric locomotive from boxing and skidding by enhancing the traction motors field are considered. The role of semiconductor converters in the improvement of rolling stock with a combined and dual power is noted. The ways to improve the efficiency of electric braking by collector traction motors are listed. The necessity of using adaptive microprocessor control systems for semiconductor converters for expanding their functional capabilities and realizing optimal parameters of direct current rolling stock is noted.

Now the problem of development of the high-speed and high-speed movement on the main railway transport that is connected by increase of traffic safety of trains and ensuring reliable work of contact suspension brackets and current collectors of an electrorolling stock is actual. For increase of reliable work of current collectors there are some ways one of which is creation of the safety devices which are built in a design of current collectors and providing their automatic lowering in emergencies. In Omsk State Transport University the current collector equipped with safety devices of new generation on the basis of the operated pneumatic devices and providing protection at failure or the increased wear of contact elements, and also breakages of a runner is developed; at rise on height of more admissible at departure of an electrorolling stock for the sign «End of a Contact Suspension Bracket» or break of contact wires; at blows and arrivals on obstacles in a contact suspension bracket. For control and management of operation of safety devices the protective pneumatic contour located on the basis of a current collector in the special case is used. At operation of one of safety devices there is a depressurization of the pneumohighway of a protective contour therefore pressure of compressed air the drive of a current collector decreases and it falls under the influence of own gravity. Restoration of a current collector possibly only in the conditions of depot or point of maintenance of locomotives. Calculation of characteristics and parameters of the device of protection at blows and arrivals on obstacles in a contact suspension bracket needs to be carried out by the given technique for zones of normal, dangerous and emergency work. For an assessment of operability of safety devices and definition of their main technical indicators and parameters in laboratory of OSTU the shock and oscillatory complex is developed for research of interaction of a current collector with a contact network.

This article presents dynamic model for numerical researches of oscillations of the main frame of an electric locomotive taking into account the impact of longitudinal efforts arising in the automatic coupler.

One of the properties of the reliability of the power supply of electric rolling stock of railways is the trouble-free operation of the traction power supply system in various modes of its operation. For post-emergency and forced modes of operation of the traction power supply system, a decrease in load capacity is characteristic. In order to ensure the throughput and carrying capacity of the railway section by traction power supply devices, it is proposed to consider the use of electric power storage devices on electric rolling stock and in the traction power supply system. Studies conducted by domestic and foreign researchers allow us to evaluate the effectiveness of alternative solutions to improve the reliability of power supply, which include various options for the use of electric power storage devices on electric rolling stock and in the traction power supply system. This article presents the results of a review of these solutions, a simulation model of a traction power supply system and an electric rolling stock with power storage devices based on various batteries and a supercapacitor is proposed. Modeling of changes in the modes of operation of the traction power supply system is carried out taking into account the state control of switching devices. The calculation results allow us to estimate the voltage drop at the output of electric power storage devices, including taking into account the exponential zone of the discharge characteristics of batteries, to estimate the voltage change for a given electric traction load depending on the energy intensity of the storage device, made on the basis of the most common types of batteries and a supercapacitor.

The article considers a suitability of mathematical model of stretched rod to determine the relationship of the parameters oscillations of the contact wires and their tension. This model allows you to determine the tension by the frequency oscillations of the contact wire obtained after the passage of the current collector. In this case, the speed of the electric rolling stock will not affect the frequency of the damped oscillations. Thanks to the proposed model, the labor intensity is reduced of determining the tension of wires without interruptions in the movement of trains is reduced and there is an opportunity of operational monitoring of the state of the contact suspension remotely.

The article substantiates the need to update the normative documentation for the selection of smoothing devices for DC traction substations. General requirements for smoothing devices, labor protection and electromagnetic safety requirements are formulated. The main schemes of smoothing devices used at DC traction substations are considered. Recommendations have been developed for the selection of smoothing device schemes for the modernization and construction of new traction substations, taking into account their energy efficiency.

In article the way increases in system effectiveness of cooling locomotives in operation - use relaunches of heat carriers between contours is considered.

The subject of the study is energy efficiency of traction power supply system and traction electric drive of electric locomotives. The article is scientifically based on the assessment of the energy efficiency of the mutually connected system of electric traction of trains. The study is aimed at solving problems on reduction of voltage losses in the contact system, active power in the contact system and traction electric drive of electric locomotives. This is possible due to the full and continuous use of the electrical potential of the power supply system. The research methodology is based on the law of energy preservation, mathematical modeling of the energy process and spectral analysis of voltage and current on the current collector of the electric locomotive. Analytically and by results of calculation it has been proved that significant losses of voltage, active power in the contact system, traction electric drive of electric locomotives are caused by unsatisfactory operation of power regulators and mismatch of voltage level in the contact power network, which is necessary for realization of heavy and high-speed driving of trains. In order to eliminate the negative effect of the inductive coupling of AC traction power supply on the energy efficiency and speed of trains, it is proposed to increase the voltage in the DC contact system and develop power regulators of electric locomotives. Mathematical model of DC electric traction system shows possibilities of reduction of electric energy losses and increase of movement speed due to application of electric semiconductor variator for matching of high voltage in contact system with voltage of traction electric motors of electric locomotive.

The paper considers a traction power supply system with a voltage of 27,5 kV AC. In the MATLAB-Simulink software environment, a calculation model has been developed that takes into account the parameters of the external power supply system, the train schedule and the current consumption of the electric traction load in the inter-substation zone. It is shown that when choosing the power of the compensating device according to the average value of the reactive power consumed by one train, its passage through the inter-substation zone with direct current causes the same average power losses in the wires of the catenary as in the absence of a compensating device. An increase in the number of trains simultaneously located in the inter-substation zone with the same power of the compensating device entails a decrease in power losses in the wires of the catenary relative to a similar situation without a compensating device, however, the reactive power is only partially compensated. In the calculations of compensating devices, it is proposed to take into account the real existing train schedule, based on the probabilistic assessment of which the average daily reactive power consumed by the electric rolling stock is determined. In this case, it is necessary to take into account the power losses in the catenary. The use of unregulated compensating devices is advisable in areas with a constantly present load. When choosing step devices for transverse capacitive compensation, it is proposed to calculate their power based on a probabilistic analysis of the train traffic schedule and current consumption in the inter-substation zone. When the probability of the appearance of a certain number of trains exceeding 50%, the most effective are compensating devices, the power of which is selected on the basis of the average power consumption of all trains without taking into account the time of no load in the inter-substation zone, as well as two-stage devices, the power of the first stage of which is selected according to the current consumption of the two most likely occurrences of the number of trains.

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 analysis of the influence of operating modes and the development of the residual life, expressed through thermal wear of the insulation of the asynchronous traction motor. The research subject is to obtain new patterns of change in the residual life of the stator winding insulation, which make it possible to determine the specific life of the winding for each mode of the asynchronous traction motor. The research aim is to create a system for determining and assessing the residual life by developing methods and technical means of monitoring and comprehensive diagnostics, as well as theoretical justification using the method for determining additional thermal wear of the stator winding insulation, taking into account the combined effect of the starting transient process, the long-term allowable load schedule and the maximum allowable temperature values. To determine and assess the possible residual life, the method of sequential influence of starting transients, maximum permissible load curves, as well as long-term overloads at the maximum permissible temperature, taking place under various operating factors during the movement of electric rolling stock, was used. The expediency of determining the function of uneven resource development, which has a monotonic character and is approximated by a linear double exponential and exponential functions, is shown. Specific proportionality coefficients are experimentally determined, which characterize the decrease in the dielectric strength of the insulation with sequential alternation of maximum and long-term permissible loads and maximum permissible temperature values, followed by obtaining an analytical relationship that predetermines the insulation resource. It is shown that the determination and assessment of the residual resource under typical modes practically makes it possible to clarify the timing of preventive measures and predict the expected duration of accident-free operation and forestall the premature failure of the asynchronous traction motor.

Flow ranges are given in article by an air stream of the aerodynamic device of a current collector the AIST, received by calculation, using which aerodynamic characteristics of this device are defined. Experimental aerodynamic characteristics of a current collector the AIST of heavy and easy type with use of the aerodynamic device are provided.

The article describes trends in the technical development of fixing devices for containers, called a "fitting retainer". Containers have gradually conquered the transportation market in the USA, Europe and Asia. And each means of transport: road, marine and railway one needed devices to fix containers, because all participants of the transportation process are responsible for the safety of goods. In the period of the appearance of container transportations, commercial agreements between operators and transport companies played an important role, influencing the unification of overall dimensions and weights of containers and transported goods, which was a prerequisite to create fittings for containers and, as a result, fitting retainers for all means of transport. The domestic regulatory framework also required updating, monitoring a large number of flat wagon manufacturers and taking into account severe operating conditions of containers throughout the entire railway network. With the rapid development of the container transportation market on long routes from China to Europe and the transition to the technology of accelerated container train sets based on high-speed flat wagons, it becomes necessary to solve the issue of wind protection of empty containers and low loaded containers, taking into account the speed of up to 140 km/h. Well-known technical solutions from different manufacturers to fix containers in retainers of special shapes and with additional fixing through a retainer hole have been analyzed. An original technical solution of the fixing device is proposed, performed in the flat wagon opposite each fitting to install the container. By turning this device using man power, each corner of the container can be fixed to prevent empty containers from falling (tippling) from flat wagons when exposed to wind loads, which meets requirements of safety, operation and reliability of fixing the container in the flat wagon.

Principal directions for increase of locomotive operating efficiency are determined in the article based on statistical estimates as per data on the main domestic locomotive series. Work ratio is suggested as universal indicator. It is demonstrated that in addition to locomotives' reliability enhancement, increase of the trains' haulage management system efficiency is also a large reserve. It is proven that the number of locomotive units can be reduced at least by 2,000 thous. units.

In article the question about possibility of extension of service life of carriage wheels by influence on technological parameters of restoration of their driving profile is considered. The correlation analysis of statistical data on volumes of machining and the size of defects on a driving surface of the wheels coming to repair is made. The mechanism of purpose of an allowance for machining of a driving profile of a wheel which will allow to reduce an unreasonable consumption of metal of a rim of a wheel in shaving is offered.

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.

With the purpose of providing capacity on the West-Siberian railway, in recent times, adjustable reactive power compensation devices have been introduced. The schematic construction and parameters of such devices on the market are significantly different. In connection with this, it is necessary to choose from the set of schemes the most effective, corresponding to specific technical and economic conditions. The article assesses the power losses in the main equipment of two devices from different manufacturers, namely static thyristor compensators of reactive power produced by "KER Holding" Kazan and "Aidis groups" Moscow, installed on the Alambay and Novaya Dubrava sectional posts of the West Siberian Iron roads. The power losses in the equipment are calculated taking into account additional losses from the influence of higher harmonic components. The analysis of the circuit design of both devices in terms of loss reduction is carried out. Dependences of power losses in their elements on the generated reactive power and the current of the thyristor-reactor group are constructed. Probabilistic functions of the distribution of the current of the titrator-reactor groups of devices are given at preset settings. The results of measurements of power consumption of devices for own needs are presented. The effect of reducing power losses in the traction network from switching devices with losses in their main equipment is compared. On the basis of the work done, the elements with the greatest losses are identified. The features of each device, affecting the power loss in the main equipment, are described. Conclusions are drawn about the effectiveness of the schemes under consideration. Methods for reducing power losses in basic equipment and consumption for energy consumption are proposed.

The article assesses the state of the market of transport and cargo services in Uzbekistan, considers the problem of scientific justification of the rational placement of cargo facilities in the country. Analysis of the problems of transport services has shown that freight traffic flows have spread out, negative trends have manifested themselves in the form of regular growth in the cost of fuel and energy resources, tightening of regulatory requirements, growth of customs duties, sanctions in the form of cancellation of previously introduced benefits, and more. However, such indicators of rail freight transportation as the range of container transportation and average travel time are stable in rail traffic, i. e. the diversification of the cargo base and the tendency to full capacity utilization take place. Separately, it should be noted that rail transportation interacts with other transport industries - automobile, air, sea, river and other modes of transport - as partners, not as competitors - multimodal freight transportation is widely developed, special logistics agencies operate to ensure the organization of uninterrupted work during freight transportation. Uzbekistan's railways need to be reformed, and possibly restructured. At least, private capital funds are already being attracted to the system of private carriage operation. The article describes the scientific methods of analysis and synthesis, classification, mathematical statistics used in the study. A roadmap of qualitative transformations for the reorganization of the transport and cargo industry has been proposed, which will bring positive results for the transport infrastructure as a whole.The results of the study will further reveal the capabilities of terminal networks capable of providing in a short time the delivery of large volumes of necessary cargo to domestic and foreign markets, the uninterrupted functioning of the necessary infrastructure for the placement of cargo facilities on the railway network. The object of the study is the state of transport infrastructure with a decisive role in trade.

The article discusses the criteria used to calculate the probability of failures of devices of the current collection system due to ice and frost deposits on a catenary. The purpose of the work is to determine the influence of climatic and operational factors (including the number of vibrating pantographs, pneumatic drums on electric locomotives within the boundaries of the Directorate for power supply and devices for mechanical cleaning of ice at power supply distances) on the probability of the occurrence of failures of the current collection system and their severity, which will allow to increase the reliability of operation of traction power supply devices in conditions of ice formation and the efficiency of investments by Transenergo and the Traction Directorate for the purchase of these funds. To determine the likelihood of failures of current collection devices due to the formation of ice on the wires of the contact network, it is proposed to divide all factors into climatic and operational. The choice of factors in predicting failures was carried out using a probabilistic Bayesian network based on statistical methods of data processing, as well as correlation and regression analysis. As a result of the research, the factors influencing the likelihood of failures of current collection devices have been determined, and their significance has been assessed using the calculated variances. A method is given for calculating the probability of failure for a conditional distance of power supply, which makes it possible to assess the adequacy of the equipment of Transenergo and Traction Directorates with devices for mechanical cleaning of ice from a contact wire, vibropantographs and pneumatic drums.

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 presents the main results of experimental studies within the boundaries of the Fadino - Novoseletsk, Novoseletsk - Strela interstitial zones of the Entrance - Irtysh section. As a result of the research identified problems that currently hinder the online monitoring of operational parameters of the electric rolling stock (EPS) and power supply devices: a lack of data on the work of the traction substations, the presence of EPS without registration motion parameters (RAPS), the lack of process data collection with RAP, the lack of a single source and process for obtaining data, insufficient memory storage device of cartridge, lack of data latch on the locomotive in General, lack a set of fixed parameters, non-constant sampling of parameter fixing, insufficiently detailed final documentation, imperfect software for exporting data from cartridges and lack of binding to global time. Shown the possibility of joining data from different automated systems of JSC "RZD" and measuring systems OSTU, which will allow us to estimate the losses in the traction network, the expense on own needs of electric rolling stock , the electric power consumption for traction and return of electric energy to contact network, as well as move forward with implementation of predictive control operation modes of the electric rolling stock and power infrastructure and Railways in a changing environment in the transportation process, to ensure the best conditions for the realization of tractive effort, regenerative braking, set train schedules, including in case of critical restrictions on the part of the power supply system, preventing train traffic from stopping.

The purpose of the article is to consider the issue of calculating and selecting the settings for the operation of the short-circuit switch KZKS-3.3 when organizing the protection of a direct current contact network in emergency mode. The shorting circuit is measured by the voltage module. When the triggering conditions are met, it is the voltage module that collects the circuit to turn on the switching device of the short circuit. The important question is to choose the optimal installation location of the short-circuit switches and the voltage trip settings. The initial information necessary for the calculation of the settings is determined. The calculation procedure and equivalent circuits for the most common power supply circuits and sectioning of the contact network are given. For current protection of high-speed circuit-breaker feeders, contact formulas are given for determining the sensitivity zones. To select the optimal installation location of the short-circuit and select the voltage pick-up setting from the allowable range, a potential diagram of the contact network section is constructed. The analysis based on the potential diagram allows us to conclude that the organization of protection of the contact network in emergency mode using short circuits is effective.

The technique of a prediction of coefficient of Hurst on the basis of various ways of a prediction is offered. For a choice of a method of a prediction errors of underestimation and revaluation are entered. It is shown that if not to consider fluctuation of value of coefficient of Hurst, the demanded parameters of a multiservice network, the allocated resources of a network used for calculation or will be insufficiently for high-quality service of the arriving traffic (that is QoS indicators will worsen), or resources of a network will be inefficiently used.

This paper describes an algorithm evaluating the effectiveness of energy-saving devices and technologies, based on the methods of mathematical statistics. Diagram presented in the article. It can be applied in the traction system and power supply without traction. Approbation of the algorithm is executed in the traction power supply system. The developed algorithm includes five stages: 1. Stage calculate the required number of observations. The basis of this stage is to evaluate the dispersion and calculating on it the desired number of observations. 2. Stage of the collection and processing of data obtained before the implementation of energy-saving devices and technologies. Collection is carried out on of electricity consumption and factors influencing the process of electricity consumption. Processing includes the calculation of the correlation matrix, the coefficients of determination and the parameters of the regression equation. 3. Stage of the collection and processing of data obtained after the implementation of energy-saving devices and technologies. Data collection is carried out according to the parameters selected in step 2 and the processing is done by the calculation of the parameters of the regression equation. 4. Stage of comparing the data before and after the introduction of energy saving devices and technologies. Comparison of the data obtained before and after the introduction of energy saving devices and technologies produced using the Chow test and nonparametric mathematical statistics such as omega-square (Lehmann-Rosenblatt). 5. Stage of calculating electric power saving. The calculation is made on the consumption of electricity obtained by the regression equation before the introduction of energy-saving devices or technology by substituting the values of the factor after implementation and actual consumption of electricity after the introduction of energy-saving devices or technology. Approbation of the algorithm was successful.