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

The article is devoted to assessing the influence of diagnostic parameters for assessing the technical condition of the collector profile of rolling stock traction motors on the value of the mechanical force in the «brush-collector» contact. The results of the experimental studies of the parameters of the collector profile for traction motors EK810Ch of mainline electric locomotives 2ES6 are presented. Four-stage numerical experimental studies were carried out for the following conditions: the first stage - the height differences of the lamellas and harmonics were taken into account; the second stage - the height differences of the lamellas are taken into account without the influence of harmonics (with reduced beating); the third stage - harmonics are taken into account without the influence of differences in the heights of the lamellas (with reduced beating); the fourth stage - harmonics are taken into account without the influence of differences in the heights of the lamellas (with a multiplying factor up to a given beat). Using a mathematical model of brush movement along the collector, a degree of relationship was established between the diagnostic parameters that characterize the state of the traction motor collector profile, with the value of the mechanical force in the «brush - collector» contact. A diagnostic parameter is proposed that characterizes the spread of mechanical force values in the «brush - collector» contact of a traction motor, determined from the ratio of the force of elastic interaction of the brush with the collector and the average value of this force. An analysis of the results of the numerical experiment showed that the contact instability coefficient is largely determined by the value of the standard deviation of the lamella drops and, to a small extent, depends on the values of the harmonic amplitudes. The harmonic composition of the collector profile has practically no effect on the value of the contact instability coefficient at small values of the lamella drops. It is concluded that it is possible to use diagnostic parameters for assessing the state of the traction motor commutator surface to determine possible poor contact between the brush and the commutator. It is proposed to evaluate the quality of repair of collectors of traction motors taking into account the standard deviation of the differences of the lamella.

Proposed method for choice rational combinations of the sectional speed of an electric rolling stock under the terms of the maximum mileage with preset wear of current collector stripes and the adjustment of the catenary of existing and projected sections of power supply. The principle of operation and functionality of computer software "Program for the simulation of contact force using a nonlinear autoregressive neural network with exogenous inputs" is considered.

Wearing parts of the cylinder-piston group and crank mechanism is one of the main reasons for putting a diesel engine into repair. Timely detection of the occurrence of intense wear allows you to prevent negative consequences, make timely repairs, eliminate the likelihood of unplanned exit of the locomotive from service. As a result of the study of the intensity of accumulation of wear products in engine oil, a mathematical model has been developed, which is implemented with the use of an artificial neural network apparatus. Its use allows to carry out an operational assessment of the technical condition of diesel engine parts in an in dividing way and to improve the technological process of repairing diesel engines of the D49 type

The wheelset and its components (the axle and the wheel) are subject to technical regulation. Therefore, in order to establish the assigned service life in accordance with TRCU 001/2011 (Technical Regulations of the Customs Union) and the examination frequency taking into account the durability parameters of rolling stock components in accordance with VNIIZhT RD 27.05.01-2017, it is necessary to assess the operational loading obtained from the running testing results, with respect to the part strength characteristics which are calculated during the bench tests. At present, to estimate the stress-strain state (SSS) in various machine-building structures, the strain measurement method is widely used, which allows to assess their performance with high accuracy. However, determining the SSS of a wheelset is not only a difficult task due to the constant rotation and movement of the wheelset relative to the bogie, but also expensive due to the employment of special non-contact measuring systems. Development of a dynamic model using modern software systems allows determination the stress-strain state of the wheelset elements by creating dynamic models as a system of perfectly rigid and elastic bodies connected by strength members and hinges. To confirm the adequacy of the parameters obtained in the simulation, verification is carried out according to the results of running dynamic strength tests. Thus, using the obtained model of the rolling stock and the track it is possible to make life and durability assessment as well as optimize the main rolling stock components. On the example of a freight gondola car model, a diagram of the dependence of dynamic stress amplitude distribution on the frequency of the occurrence in the wheel has been obtained, and considering the results of the earlier bench tests of standard specimens and full-scale wheels the period has been determined for durability from the moment of crack initiation in the wheel up to its fracture, as well as the assessment of the safety factor for durability is given.

In the article there is the increase of rail circuits work stability in conditions of heavyweight traffic for AC traction sections. There is a coordinate plane graph of backward traction circuit base diagnostic states in the paper. We analyzed the results gained in the researching and suggested the way to coordinate rail shunt location and to evaluate the insulation resistance in backward traction circuit.

The article presents the results of studies of the effect of material properties and wheel failures on the process of their machining on the on the car wheel lathe. Developed by complex criterion that takes into account the effect of various factors on the allowable cutting speed. The proposed method for assessing the machinability of cutting wheels through additive criteria. The quantitative characteristics of the machinability of cutting are obtained, taking into account the macroscopic imprecision of the geometric shape, defects in the thermomechanical interaction of the wheel, brake pad and rail, surface defects of the rim, work hardening and the presence of zones of increased hardness. The results can be used in the development of methods to reduce the consumption of carbide cutting tools for machining parts of rolling stock with operational defects.

The experience of the railways electrification in Russia and the justification of the current type choice for the electrification of the Ulan-Bator Railway are considered. The calculation of the maximum mass of the wagons of freight trains of an AC electric locomotive of 2ES5K and an electric locomotive of direct current 2ES6 in the conditions of the Ulan Bator Railway is performed. The rationale for choosing the kind of current for the electrification of the Ulan Bator railway is presented.

The article presents the method of calculating the amount of products of combustion of diesel fuel, gas-and-diesel and model calculations are made in relation to the diesel engine 16ЧН26/26 (2A-5D49). Parameters of the working cycle of a diesel engine operating on different types of hydrocarbon fuels, derived using a combination of methods Grinevetskiy-Mazinga and vibe. Calculation of the amount of harmful emissions and the amount of greenhouse gases is made using the method of equilibrium composition due to changes in the thermodynamic parameters and elemental composition of fuel burnup fuel mixture the positions of controller driver

The introduced results of the investigation by valuation of efficiency the employment of the locomotives of the diesel (the diesel locomotives 3TE10M, UzTE16M3) and of the electrical (the electric locomotives 3VL80S) tractions in the plainly direction of railway track by the method of averagin design values. Modified average significances main indicator move working of the investigations of the diesel locomotives 3TE10M, UzTE16M3 of the evaluation mind numeral and table facts, and also graphic arts dependences, representative oneself arithmetical mean value with taking into account of the movement goods trains without any stops and with stops on the spaces stations, passing - tracks and divides points, which have received in the result to uses of the traction calculation for different conditions organization of the goods movement. Designate equations for organization calculation values mention exponents in the accepted range changing of the masses trains

The results of the investigations on the evaluation of efficiency use of the diesel locomotives UzTE16M4 in the mountainous direction Kumkurgan - Tashguzar of the Uzbek railways track by of the movement goods trains with stops and without any stops on the spaces station are presented.

Investigation of instantaneous and average velocities of train movement, their properties and their application, including calculation of speed coefficients and movement time. Determination of influence of the movement speed and its restrictions, stops and delays onto travel time losses and traction energy consumptions of loaded and empty trains. Time and energy saving estimation due to the application of regenerative braking on the electric locomotive. Development of the recommendations for increasing average speed, decreasing travel time and energy consumption of freight trains.

The experience gained in the operation of high-voltage vacuum circuit breakers VBO-25-20/ 630UHL1 indicates an incorrect assessment of the mechanical resource of its individual components and elements. Despite the repeated improvement of the design of the main switch drive, applicable both as part of the new «Ermak» series locomotives starting from number 1000 series, and in earlier numbers, the dynamics of malfunctions continues to persist to the present time. One of the most important elements of the main switch is a latch designed to hold the elements of the drive mechanism in the on position, the failure of the latch entails the failure of the entire section of the locomotive. The article considers three latch upgrades previously proposed by the manufacturer, a kinematic scheme of the drive with a vacuum arc-extinguishing chamber of the switch is developed, the parameters of the preload and trip springs in the drive are calculated, the forces operating during operation are determined. On the example of the latest modernization of the latch using the finite element method in the SolidWorks Simulation software package, a strength calculation was carried out, according to the results of which the stresses arising in its design were determined. As a result of the analysis of the finite element model, the forces critical for the structure are determined, a graph of the dependence of the structural strength margin and the maximum stress in the structure on the acting forces is developed. According to the results of the study, the force at which the most favorable value of the safety factor is provided is determined, for which it is proposed to reduce the critical force by changing the parameters of the compression springs and disconnecting the drive of the arc extinguishing chamber. A loading diagram with the drawing dimensions of two modified springs has been developed.

The article includes research results of analyzing and evaluating 3ТЕ10М diesel locomotive`s efficiency on a hilly-mountainous direction Marokand-Navoi of Uzbekistan railways while hauling freight trains with and without stopping on through stations (division points).Main parameters of basic movement work of researched UzTE16M3 diesel locomotives are shown as tabled values and graphic dependencies,also equations of organizing necessary calculations mentioned above in accepted range of mass variation are marked here.

In the article the most effective way to detect heat losses associated with loose-Stu walling. A method for use of aerodynamic and thermodynamic - cal research with the possibility of the use of rail transport.

In order to extend the service life of electric machines traction rolling stock has been proposed recovery technology insulation using infrared energy, will improve the quality of insulation in terms of the breakdown voltage and hardness. This article analyzes and estimated of experimental studies conducted in two different meaningful of the work in this direction. Presents an analysis these works in terms of distinctive features and conclusions of the pilot studies. According to the analysis formulated a new hypothesis about the need to address when capsulating the insulation and its elasticity. Also set new directions for future research.

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.

The method of creation of mathematical models of the mechanical oscillatory systems which are turning on in the structure mechanisms with kinematic couples of slippage is offered. It is shown that introduction of mechanisms can be interpreted as introduction to initial model of the additional feedback, in general, to steering on absolute speedup and on an absolute deviation. A basis of the offered technology of creation of mathematical models are representations that in the presence of the mechanism or a mechanical chain of other look power and kinematic indignations form various structures of dynamic interactions. The analytical ratios defining dynamic properties of systems are received. The features of dynamic properties which are shown in various forms of dynamic interactions and frequency characteristics are considered.

The paper describes the physical nature of the occurrence of disturbing forces in traction gears during intermating teeth and determination of the amplitude-frequency content of the spectrum. In addition, the experimentally determined defects arising elements locomotive traction gearing.

The possibilities of improving speed and reducing the time of passenger trains on the Trans-Siberian railway, including through new passenger locomotives EP1, EP2K, EP20.

In article are considered standard technologies of ultrasonic inspection of under-hub parts of press-fitted wheelset axles accordingly to existing regulations: GD (Guidance Document) 07.09-97 and STO (Standard of the Organization) Russian Railways 1.11.002-2008, and proposed improve-ment measures of nondestructive inspection that are confirmed by calculation and experimentally

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.

The article consider the mathematical model for integrated evaluation of the innovation cars operational efficiency in the freight traffic. Created the complex systems of freight rolling stock efficiency indicators of the innovation cars providing aggregate multiplicative effect of increase in productivity. Presents the calculations of the rolling stock productivity indicators model change from operation for one production cycle of innovation cars in the cargo movement. The executed in the article researches and received modeling results show that the rolling stock use efficiency in the cargo movement are consider into account of influence factors from the innovation cars implementation.

The article presents the method of calculation of heat capacity working relations in the process of fuel combustion. Analytical dependence of heat capacity ratio are presented depending on the temperature of products of combustion, excess air ratio and proportion of burnt fuel for different formulations of mixed types of hydrocarbon fuel.