Journal of Transsib Railway Studies V.3(39), 2019

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 article considers phenomenological and modelling approach to researching of interaction of a deformable wheel and a plane of support, their advantages and disadvantages are mentioned. In the context of phenomenological approach the five methods of locomotive tangent tractive force calculation were considered. There certainly must be pseudo-creeping to let locomotive tangent tractive force do work and change the kinetic energy of a train in the point of wheel and rail contact. Locomotive tractive force experts calculate the power as product of the locomotive tangent tractive force and the velocity of translational motion of a train, although in fact the velocity of the point of force application must be assumed. It is applied to a wheel pair, then the velocity of this point must be used to calculate the locomotive power. According to this fact the locomotive power is found several tens of times reduced.

The results of the train traction electricity consumption forecasting, which were obtained on the basis of existing methods and the interval regression method, was analyzed. The errors of forecasting according to three methods compared with the real electricity consumption were determined. The authors put forward the software for calculating the predicted values of electricity consumption for train traction, taking into account the operational indicators of the electrified railroad under conditions of uncertainty in the initial data.

The expediency of introducing dynamic models of defect development into the practice of vibration diagnostics of rotor mechanical units is substantiated. It is shown that as a basis for the creation of models it is advisable to use empirical data. An example of a dynamic model of a small gear defect of a wheel-gear unit is given. The approximate amount of work on the creation of dynamic models is determined. Methods of realization of dynamic models of defects "in the big" are offered.

In accordance with the long-term development program of JSC Russian Railways until 2025, it is planned to increase the level of economic connectivity of the territory of Russia by expanding the network of high-speed and high-speed transportation. This involves not only the construction of new high-speed highways, but also the modernization of the structures of individual components of rolling stock, as well as the introduction of energy and resource-saving technologies. The use of contact elements with an extended service life is one of the most economical and least costly ways to ensure reliable, economical and environmentally friendly transmission of electricity to rolling stock. An increase in the service life of the current collector element can be achieved, among other things, by reducing wear by the correct selection of contact pair elements, both from the point of view of their tribocompatibility and the ability to ensure high quality current collection. A methodology for conducting experimental studies of contact pairs of current collection devices has been developed and successfully tested at OSTU, which involves bench tests for each pair of contact materials “contact insert - contact wire” in order to determine their optimal combination to reduce wear and increase resource. Estimation of the amount of wear and prediction of the life of the elements of the contact pair is carried out including using mathematical models. However, the use of existing models for predicting wear under conditions of high-speed movement is not accurate enough due to the lack of consideration of the aerodynamic effects and the speed of the rolling stock on current collection processes. This article discusses the improvement of the mechanical component of the wear model of the elements of contact pairs of current collection devices in high-speed conditions. The graphs of the mechanical wear of the contact elements are obtained experimentally and as a result of calculation by a mathematical model. The analysis of the graphs allows us to conclude that it is possible to use an improved mathematical model for modeling the mechanical component of the wear process of the elements of contact pairs with a maximum error value of not more than 5 %.

This article presents the results of changes calculations in the energy efficiency indicators of the Moscow Central Ring, such as the specific consumption of electricity released for traction by trains of traction substation meters, specific recovery, technical losses of electricity in the traction power supply system when it is transferred to electric rolling stock, including technical recuperation energy loss, depending on various installation options of rectifier-inverter converters in traction substations part.

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 paper considers the influence of the force characteristics of the damping apparatus on the value of the maximal longitudinal forces arising between the cars. Using the computer program MSC.ADAMS, we performed the simulation of shunting collisions of cars and train transient movement modes. The dependences of the maximal forces at cars' collision at various velocities on the shape of the elastic elements' force characteristics are determined. The operation of various shock dampers for the case of the train starting off electric braking and movement through the parts of the longitudinal track profile was estimated. It is shown that shock dampers with a rapidly growing line of load lead to the emergence and propagation of large shock forces along the train, while a slow growth of the force leads to their reduction due to the amplitude increase in elastic vibrations propagated along the train length . We propose to use high-energy-damping devices to reduce the longitudinal forces in the train, which are characterized by the force slew rate substantially depending on the compression velocity of the shock damper.

The operational reliability of the electrification and power supply system and the associated traffic safety is mainly determined by the technical condition of the contact network-an element that is extremely difficult to reserve in any way. The state of the contact network devices of the East Siberian railway is indirectly characterized by periods of electrification of sections. The equipment of the contact network, put into operation in the 1960s and 1970s, has developed its design life, does not have the required load capacity enough and reduces the reliability of the electrified section. The article shows that the purpose of improving the reliability of electrical equipment in the operation of power supply devices is to predict the state of its elements, in particular the metal supports of the contact network, as an object of study. Correctly assess the state and resource of the contact network devices will allow the use of the latest diagnostic systems by personnel in practice, using mathematical apparatus and modeling methods. It is shown that by monitoring various parameters characterizing the support, it is possible to detect a change in the technical condition of the object of study in time and to carry out maintenance in the period of time when there are deviations of parameters beyond unacceptable limits. The statistical data on the state of the support economy at the VSZHD are summarized, the main types of damage to metal support and supporting structures are given. It is shown that new types of damage to metal structures, not classified earlier, are revealed, that qualitative and quantitative assessment of the state of metal supports of the contact network, which have various structural damage is possible using methods, modeling, simulation and evaluation of the state of structures. FEMAP, an independent computer-aided design system from Siemens PLM, is used as an independent full-featured environment for modeling, simulation and evaluation of the results of the analysis of the characteristics of metal supports of the M6/10 model

The article outlines modern approaches to determining the maximum permissible continuous current of current collectors when stopping and in motion. The features of techniques that reliably take into account operational factors when conducting tests in laboratory conditions are considered. A mathematical model is given for studying the distribution of current load in emergency mode of breaking a current-carrying shunt.

The article deals with the issues of improving the model of interaction with customers through the introduction of digitalization projects in the sphere of freight rail transport, describes the changes in the main functions of the company's divisions and technological aspects. The technological and economic effects of the development and implementation of freight transport digitalization projects on the example of improving the digital platform of interaction with customers are determined. The model of CRM-system implementation of transport services digitalization is worked out, investments on its development and implementation are defined. The main categories of risks with the greatest direct impact on the effectiveness of the new model implementation of interaction with customers are considered. The digital platform of interaction with the client allows to carry out the order of freight transportation service by rail without any additional financial and technological expenses connected with obtaining the qualified electronic signature, to simplify the organization of contractual work to obtain services and payments for them.

The article describes the possibility of applying diagnostic algorithms, taking into account the complexity of the examination, applied to a specific problem of searching for damage in receiver of station's tonal track circuit. The aim of the work is to justify the need to take into account the complexity of the survey when compiling these algorithms. The order of compiling the diagnostic algorithm is shown, conditional probabilities, diagnostic weights, private and general diagnostic values are calculated. On the basis of the calculations performed, algorithms for diagnosing taking into account the complexity of the examination in receiver of the tonal track circuit was compiled. The work results presented in the article can be used for technical maintenance of automation systems of operating railways.

The wet method of cleaning the blast furnace gas from the particles of grate dust is one of the most common. The hollow nozzle scrubber is the device for wet cleaning of blast furnace gas in which the cleaning of blast furnace gas is carried out due to the interaction of particles of grate dust with droplets of dispersed technical water. The principle of cleaning the blast furnace gas in the hollow nozzle scrubber is based on the inertial mechanism of collision of grate dust particles with droplets of dispersed process water. After the particles are wetted, stick together and fall out of the flow of the cleaned gas under the influence of gravity. In this paper, we propose a method for calculating the efficiency of blast furnace gas purification in a hollow nozzle straight-through scrubber, which is based on the division of the volume of this gas purification apparatus into even sections. Because the trajectory of the droplet in the blast furnace gas flow in the hollow nozzle scrubber has a parabolic shape, radial component of the absolute velocity of the droplet s taken into account in this technique to determine the efficiency of catching dust particles. The correction factor in the expression for determining the fractional efficiency coefficient of the blast furnace gas purification from the grate dust determines the presence of «dead zones» when the dusty gas is irrigated with technical water sprayed by involute injectors. In addition, the presented method takes into account the increase in the efficiency of cleaning the blast furnace gas due to the process of condensation of water vapor from the flow of dusty gas in the lower part of the hollow nozzle scrubber.

The use of new self-supporting insulated wires and high-temperature wires in the operation of power lines allows increasing the capacity of lines and, as a rule, reducing operational costs. An optimal utilization of the power line load capacity depends on the precise determination of the permissible current loads. The values of permissible currents and steady-state temperature are the main parameters of the line operating mode, affecting the strength and sag of the conductor. The temperature of the wire depends on weather conditions and current load. There are methods for determining the temperature and permissible currents for widely used traditional wires such as AC. They are partially outlined in the EIS (Electrical Installation Standard) and the standard of PJSC FGC UES (Federal Grid Company of Unified Energy System) of 2013. However, there is lack of studies in new types of wires. The paper considers the effect of weather conditions and load on the temperature and real-power losses in insulated and high-temperature wire, and solar radiation is under special consideration. For comparison, we present the results of calculations on traditional AC wires. The research shows that solar radiation, being taken into account, provides an increase of real-power losses of about 2 % with the given values of load and weather conditions. Calculations of permissible current values according to the developed technique for classical AC wires reveal a high coincidence with the values from PJSC FGC UES standard. The relative error is within two percent, and the proposed method is more generalized. It allows simultaneous analysis of both uninsulated and insulated wires. Due to the widespread use of self-supporting insulated wires, power industry experts can use the developed software in the design and operation of modern power lines to optimize capacity.