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The article contains methodology for assigning losses in two-element frequency converter (in rectifier and dc-ac converter). which allow to replenish mathematical model of back to back rig test method for induction motors and to use it in design induction motor rig test, also for calculation electrical power test rig which consumed from electrical network. Practical value of the methodology is no need in using electrical measurement instrument for ac-dc power with frequency different from 50 Gz.

The article contains information about policy public corporation «RZD» in energy-saving and energy efficiency. Assessment of energy efficiency of application back-to-back method in testing induction tractive motors was executed as an example on modeling testing process of motors type NTA-1200.

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.

He method of researching the dynamic properties of the railway crew in the action on it harmonic parametric perturbation, caused by the changing rigidity of the base of the rail, is set out. For such differential equations there are no regular methods of solving them, moreover, their exact solutions are not known at present, so they are used by approaching methods. A two-degree mechanical system with a harmonic parametric perturbation described by a system of ordinary homogeneous differential equations is considered. One of the hard-bone parameters is a function of time and varies from 2000 to 3000 N/m. To calculate the boundaries of dynamic instability (parametric resonance) a method of generalized Hill definers is used, which does not require the introduction of small parameters. The area of interaction of parametrically excited and forced vibrations has been determined.

In this paper analyzed the design of cast and weld side frames three-piece bogies. The directions of further improvement design side of a bogie frame.

One of the many topics on which he worked V.V. Lukin in end of his life, was to improve the cast parts bogies freight wagons using the finite element method. In this paper the authors shows that the method of finite element analysis of the stress-strain state of two of the most essential parts a three-element bogie freight cars to further improve the their design.

On the basis of experimental data thereis a mathematical model in thisarticle. Its made from the registration options in acfual operation mode of the locomotive. This mathematical model describes the technical condition of the locomotive and evaluates the parameters and characteristics. Considerable attention is paid to complex state operation of the facility. In dealing with the mathhematical model it’s defined the main locomotive operation indicator.

Annotaion. The relevance of carrying out research works on improving the regulatory and methodological base in the development of promising railroad rolling stock structures with the use of new structural materials with nonlinear properties during deformation (physical nonlinearity) is substantiated in the work. The possibility of using the finite element method (FEM) procedure for creating such constructions is considered. Dependence of stresses on deformations is approximated by a cubic parabola. This made it possible to obtain generalizations of the well-known relations and algorithms of the classical theory of FEM with a nonlinear relationship between stresses and deformations. The proposed technique was tested in the evaluation of the stress-strain state (SSS) of an aluminum gondola car under various standard loads according to the 1st design mode. The effect of physical nonlinearity on the SSS of a spiral beam of a freight gondola car of aluminum alloy AMg6 was estimated. The calculation of the stresses generated by the action of a longitudinal force with eccentricity shows that the stresses in the nonlinear approximation are 13% lower than the corresponding stress values obtained by calculation in the linear theory. The results obtained can be recommended for the development of pilot projects of new structures optimized for weight and strength characteristics.

Features of the methods of calculation of a braking distance of the train applied now are considered. The main shortcomings of the most widespread method of definition of a braking distance on speed intervals are shown. Authors offered the new method of calculation allowing to consider critical parameters of process of braking (speed of a brake wave; character of an indicator diagram of the brake cylinder and mode of a brake; the actual initial speed for calculation of a way of action of brakes of the train). For verification of the offered method computer modeling is executed and the analysis of results of the different methods of calculation of braking length received at application is carried out. The new method allows to make calculation of braking length of the rolling stock more precisely.

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.

Railway transport faces the challenges not only to ensure uninterrupted transportation of national economic goods, but also to develop new locomotives and increase the efficiency of their use. In particular, the currently accepted mode of starting diesel locomotives of the UzTE16M type leads to additional consumption of fuel resources, therefore, research on the development and improvement of the conditions for starting diesel locomotives of this type is relevant. Based on the study of previous studies and designs of various systems in order to facilitate the start of diesel locomotives with electric transmission, it is necessary to establish the available reserves of the power circuit and control circuits. The article considers a mathematical model of torsional oscillations in a diesel generator start-up system with two concentrated mass moments of inertia. Torsional oscillations between the traction generator and the crankshaft of diesel locomotives of the UzTE16M type have not been previously considered. In this article, the problem of torsional oscillations of the reduced masses of the armature of the traction generator and diesel engine in the mode of starting the DG from the battery and additional devices is solved. The Lagrange method has derived a system of mass oscillation equations based on generalized coordinates of elastic oscillations between the masses of the armature of a traction generator and a diesel engine with a variable mass moment of inertia. For the resulting system of equations, the solution is performed by the method of operational calculus, taking into account the accepted functions of mass moments of inertia, moments of driving forces and resistances. Conclusions are drawn that the operation of the diesel starting system on diesel locomotives of the UzTE16M type is determined by the functions of the reduced mass moment of inertia of the diesel, the driving torque and the angular velocity function; the resulting solution makes it possible to calculate the driving torque and the range of angular velocity changes when starting the diesel generator set of UzTE16M locomotives for further comparison with experimental data; when using the recommended electric scheme for starting a diesel locomotive, an increase in the driving torque of the diesel crankshaft and the angular acceleration speed of the traction generator armature is achieved. Based on the developed model, it is recommended to determine the angular velocity of the diesel crankshaft.

This article contains results of experimental studies on the formation of corrosion products as a result of aggressive environment and electric currents action on the reinforced concrete structures. There are discussed a method of creating models with artificial electrocorrosion under conditions close to real working. The results of testing models using the X-ray method and modeling their strength characteristics are presented.

In this article, the main methods of technical diagnostics of diesel fuel equipment are considered. The faults they detect are listed. The principles of the methods work are examined in detail, the shortcomings and advantages of the chosen methods are revealed.

Annually locomotive-building plants, equipment suppliers and service companies develop organizational and technical measures aimed at improving the reliability of products. Thus, within the framework of the contract for the supply and maintenance of electric locomotives of the ERMAK series, a number of corrective measures have been implemented in more than thirty directions, many of which have achieved a positive result. However, during the long-term operation, more and more new hidden technical defects are revealed, and in rare cases, the measures taken are not enough. The manifestation of systemic inconsistencies is random in nature, thereby they negatively affect the dynamics of the average daily mileage and the linear mileage completed over the entire life cycle, causing unpredictable fluctuations, and as a result, the organization of service planning and budgeting to support the life cycle of locomotives. Therefore, there is a need to develop a model for a more accurate forecast of the average daily mileage for a long period, considering the impact of system inconsistencies and corrective measures to improve the reliability of nodes. The article uses the Pareto principle to analyze system malfunctions of locomotives manufactured by PC NEVZ LLC for the period of operation from 2018 to 2021, analyzes the dynamics of the average daily mileage of the locomotive fleet of the Far Eastern Traction Directorate with the use of a statistical and analytical method, analyzes the impact of failures on the average daily mileage using the Fourier time series forecasting method. On the example of malfunctions of power current-carrying buses of a rectifier-inverter converter and malfunctions of latches of a high-voltage vacuum circuit breaker, the influence of malfunctions of critical nodes is evaluated.

In this paper we presented an option accounting compliance joints through mathematical modeling of prefabricated single-walled cylindrical geometric op-totropnyh shells on the basis of the contact boundary value problem of structural type.

A mathematical model describing the dynamics of mechanical oscillatory systems «rolling stock train -railway track» in the vertical longitudinal plane of symmetry. Is equivalent to converting the design scheme. Linearization of nonlinear characteristics in ways. A model of the «generalized» track to assess the existing shock pulses from the joints of rails.

The article deals with the suitability of wave response method aptitude for traction engines turn-to-turn armature coil insulation testing and development of testing coil adequate model for further researching of physical processes occurring while testing. The method of wave response readout in armature coil reported is described in the article. The equivalent circuit of armature coil relating to wave response method is given. The wave responses got during physical model testing, simulating in MATLAB are shown. The real and simulating results analysis allows you to approve the proposed equivalent circuit adequacy. This equivalent circuit may be used for simulating of traction engines insulation fails relating to wave response method.

This article is devote to the development of software for analyzing and transforming data from studies of the collector surface traction motors using a device of control profile commutator PKP-4M. The use of this computer application during the processing of the experimental data will improve the reliability of the control profile of the commutator, and to calculate the main diagnostic parameters characterizing the effect of the profile on the commutation process.

Each of the proposed circuits is composed of inverters. These devices are sources of non-sinusoidal voltage, whose frequency can vary within a wide load range of the test engine. Therefore, to measure the power in such conditions requires either the use of special complex of hardware-software complexes to perform the direct measurement or the development of indirect methods for determining capacity. Such methods proposed for each of the schemes. The essence of the developed methods consists in a preliminary experimental determination of the dependency of the losses in the rectifiers and rectifier-inverters circuits from the power supplied to him. These dependencies are further processed during the test, using only the General-industrial electric meters that measure power consumed by the frequency Converter, and the power consumed (generated) asynchronous motors is determined by the indirect (calculated) by. On the other hand, pre-experimentally received dependence of losses in frequency converters from power consumption trolled (generated) asynchronous motor energy, you can calculate the power consumed by the frequency Converter from the network in a wide range of loads that can be used in the design of testing stations for asynchronous traction motors.

The article shows the relevance of applying the method of mutual test load of asynchronous traction motors of railway rolling stock. On the basis of the recommendations of existing standards in testing of asynchronous motors is made up of a sequence of acceptance testing of asynchronous traction motors provided in the form of an algorithm. In line with the scheme proposed for testing procedures on the use of the basic equipment of the circuit. The analysis of the main types of tests, the comparison of the classical means for testing the functionality of the inverters eliminated the need for additional DC sources in determining the resistance of the stator windings, additional brake and step-down transformers during short circuit and experience to carry out simultaneous testing of two induction motors increased speed at the stand of mutual load.

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 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».

The article describes themain types ofdamageinsulatorscontact network, presents statisticsfortheirfailures. Identified weaknessesin existing methodsof diagnosingsayabout the relevance ofthe problem, especially in the areasof railwaysDC. Made experimental investigationson the measurementof the electrostaticfield on theinsulator strings. Analysis of the studiesshowed that the presencein the string of faultyinsulatorsleadsto an increase inthe electrostatic fieldaround them. Proposed a technicaldevice noncontact measurementof electrostatic fieldandmethod of determining thefaultyinsulatorin the string.

In this article a shielding effectiveness calculation method for the radio electronic equipment is considered. Monolayer and multilayer shields made with aluminum, cuprum, steel is investigated. Interaction of pulse magnetic field and conductive shield is simulated using finite difference time domain method. Frequency and time dependencies for the shield impedances are shown. Also pictures of electromagnetic field distribution near shielding are presented. Time dependencies of electric field on the shield external and internal borders are shown.

The method of definition of dynamical reactions in mechanical oscillation systems with rigid body with two degrees of freedom is discussed. Understandings about possibilities of creature of structural analogy schemes in relations with systems of automatic feed-back control are used. Transformations of structural schemes for selection of chain of feed-back ties in accordance in examination of object are shown. Such ties represent the dynamical reactions which are looked. Compare analysis with using several approaches are made. Peculiarities of method of definition of dynamical reactions in contacts of rigid body with elastic elements of mechanical oscillation systems are shown.