Locomotive Traction Research Articles

An analysis of the impact of agricultural tractor seat cushion materials to the level of exposure to vibration

During everyday operations with tractors, drivers are exposed to harmful effects of various factors. In addition to unfavourable temperature and humidity, dust and noise, one of the factors harmful to driver’s health is vibrations. They come from the tractor engine and from the roughness of the ground and are transferred to the cab and through the seat to the body of the driver. In case of high level magnitude vibrations and a long period of exposure to them, many health problems occur. The harmful effect of the vibrations is especially obvious in older models of tractors. High intensities of vibrations (above permitted limits) were found during the measurements of vibrations at the driver seat in such tractors. This study is an attempt to reduce the vibration levels using various vibration-absorbing components, such as cushions, at driver’s seat. The results of the measurements showed that the vibration levels were significantly lower in comparison to original seats.

Geometrical specifications accuracy influence on the quality of electromechanical devices

To improve the quality of electromechanical products is possible due to the geometrical specifications optimization of values and tolerances. Electromechanical products longevity designates the rolling-contact bearings of the armature shaft. Longevity of the rolling-contact bearings is less than designed one, since assembly and fitting alter gaps, sizes and geometric tolerances for the working parts of the basic rolling bearing details. Geometrical models of the rolling-contact bearing details for the armature shaft and the end shield are developed on the basis of an electric locomotive traction motor in the present work. The basic elements of the details conjugating with the adjacent details and materializing the generalized and auxiliary coordinate systems are determined. Function, informativeness and the number of geometrical specifications for the elements location are specified. The recommendations on amending the design documentation due to geometrical models to improve the accuracy and the quality of the products are developed: the replacement of the common axis of the shaft’s technological datums by the common axis of the basic design datums; coaxiality tolerances for these design datums with respect to their common axis; the modifiers for these auxiliary datums and these datums location tolerances according to the principles of datums uniformity, inversion and the shortest dimension chains. The investigation demonstrated that the problem of enhancing the durability, longevity, and efficiency coefficient for electromechanical products can be solved with the systematic normalizations of geometrical specifications accuracy on the basis of the coordinate systems introduced in the standards on geometrical product specifications (GPS).

A study of the dynamics of the processes in locomotive traction motors during switching

A mathematical model for studying the dynamic variations in the voltages and currents of traction electric motors in the case of switching has been proposed. The influence of the behavior of the transition resistance of switching devices on the mode of operation of a traction electric motor has been studied.

Оптимізація керування мотор-вентилятором охолодження тягових двигунів вантажного локомотива з асинхронним тяговим приводом при русі на ділянці з заданим профілем та графіком руху

The work is devoted to the development of methods for control optimization of the motor-fan of traction engines of a freight locomotive with an asynchronous traction drive when moving to sections with a specified profile and traffic schedule. The peculiarities of the methodology are the following: the method is based on the solution of the problem of conditional minimization by the criterion of the economic efficiency of the ventilation and cooling system by the Weyl method over the generalized golden section; as the optimization parameters, the following values are chosen: the temperature of the motor-fan on and the number of pole pairs of the motor-fan motor, and inequalities are also established; The task of analyzing the ventilation and cooling system of traction motors is based on modeling the thermal conditions of an asynchronous traction motor according to the generalized equivalent thermal scheme.

Utilization of waste cooking oil as an alternative fuel for Turkey.

This study is based on three essential considerations concerning biodiesel obtained from waste cooking oil: diesel engine emissions of biodiesel produced from waste cooking oil, its potential in Turkey, and policies of the Turkish government about environmentally friendly alternative fuels. Emission tests have been realized with 35.8kW, four-cylinder, four-stroke, direct injection diesel tractor engine. Test results are compared with Euro non-road emission standards for diesel fuel and five different blends of biodiesel production from waste cooking oil. The results of the experimental study show that the best blends are B10 and B20 as they show the lowest emission level. The other dimensions of the study include potential analysis of waste cooking oil as diesel fuels, referring to fuel price policies applied in the past, and proposed future policies about the same issues. It was also outlined some conclusions and recommendations in connection with recycling of waste oils as alternative fuels.

PERFORMANCE AND EMISSION OF POLLUTANTS OF AN AGRICULTURAL ENGINE WITH TWO POWER TAKE-OFF SETTINGS

Farming operations are usually performed implements driven by a power take-off (PTO) from tractors. Some manufacturers offer PTO settings named as economic (540E). Such configuration drives implements at lower tractor’s engine rotation, thus providing lower fuel consumption. An engine performance using standard (540) or 540E settings are different and poorly studied. The amounts of pollutants emitted by engines vary mainly with the applied load and rotation. The aim of this study was to compare the performance and exhaust emissions of a farming tractor engine under different PTO loads, using both standard (540) and 540E settings. Specific fuel consumption using 540E was an average 14.7% less than the standard setting. However, 540E promoted increasing levels of gas opacity, CO, CO2, NOx, and HC for the highest PTO power demands.

Multiple Fault Diagnosis for Three-level Inverter Via Wavelet Analysis and Support Vector Machine

Inverter is an important part in the locomotive traction system. In this paper a fault diagnosis method of three-level NPC inverter with two IGBT failures concurrently in different bridges was introduced. With the Simulink toolbox in Matlab, We obtained the output voltages’ difference between faulty and fault-free cases, get Ua、Ub、Uc , d-q transformation on Ua、Ub、Uc , put three-phase into two-phase, Ud and Uq. Making use of wavelet analysis to process Ud and Uq, extracted the fault feature and construct the feature vector. The samples which contain the fault information were accessed finally. With the LIBSVM toolbox, the multi-fault classifiers were established. Finally, the simulation samples were trained and tested. Experimental results showed that the classification result was fine and achieved the desired objective.

APPROXIMATION OF UNIVERSAL MAGNETIC CHARACTERISTIC FOR MODELLING ELECTRIC TRACTION MACHINES

Purpose . The scientific work is aimed to obtain an analytic expression describing universal magnetic characteristic and enabling to take into account the demagnetizing effect of the armature. On the basis of the universal magnetic characteristics one need to obtain universal expressions for inductive parameters of electric traction machines of direct and pulsating currents. Methodology. A universal magnetic characteristic (UMC) is the dependence of the relative units of the magnetic flux on the magnetomotive force (MMF) of the excitation winding. Since MMF was built for machines operating under load, therefore, in fact it is a dependency on the MMF and on the MMF of the armature reaction. For the calculation of electromechanical characteristics at constant excitation one can use one of the well-known expressions approximating the UMC. However, during modeling the electric traction engine operation in wide ranges of excitation change it is necessary the expression, in which there is a second variable in the form of MMF of the anchor reaction. Such an expression is also necessary to determine the inductive parameters of electric traction engine, to a large extent dependent on the current. The expression for the approximation of the UMC with two variables can be obtained by analyzing the magnetic field distribution in the air gap at the calculated pole arc. Findings . The author obtained expression for approximation of the UMC, which depends on two variables: MMF of excitation and MMF of armature reaction. For a particular mode of excitation weakening it is possible to convert the expression into the function of one variable, for example, the anchor current. Also, the MMF of excitation winding can be the argument. Originality . For the UMC approximation it was proposed a methodology that makes it possible to record into approximating expression the second variable in the form of the anchor reaction MMF. Practical valu e. Due to the presence of speed characteristic or saturation ratio of this electric traction engine, one can determine its inductive parameters in a particular operation mode or to obtain their dependencies on the winding currents for all modes of operation.

Friction self-oscillation decrease in nonlinear system of locomotive traction drive

The problems of the friction self-oscillation decrease in a nonlinear system of a locomotive traction drive are considered. It is determined that the self-oscillation amplitude decrease in a locomotive wheel pair during boxing in traction drives with an elastic linkage between an armature of a traction electric motor and gearing can be achieved due to drive damping capacity during impact vibro-damping in an axle reduction gear with a hard driven gear. The self-oscillation amplitude reduction in a wheel pair in the designs of locomotive traction drives with the location of elastic elements between a wheel pair and gearing can be obtained owing to the application of drive inertial masses as an anti-vibrator. On the basis of the carried out investigations, a design variant of a self-oscillation shock absorber of a traction electric motor framework on a reduction gear suspension with an absorber located beyond a wheel-motor unit was offered.

ESTIMATION OF FUEL CONSUMPTION IN AGRICULTURAL MECHANIZED OPERATIONS USING ARTIFICIAL NEURAL NETWORKS

ABSTRACT This study aimed to develop artificial neural networks for the estimation of tractor fuel consumption during soil preparation, according to the adopted system. The multilayer perceptron network was chosen. As input data: the soil mechanical penetration resistance, the mobilized area by implements, the working gear and the tractor engine speed. The number of layers and neurons varied to form different architectures. The adjustment was verified based on various statistical criteria. The values estimated by the networks did not differ significantly from those obtained experimentally. The conclusion was that the networks showed adequate reliability and accuracy to predicting the fuel consumption in each tillage system, in function of the input data and this can be a useful tool for planning and management of agricultural operations.

OPTIMALISASI KEBUTUHAN TRAKTOR UNTUK PENGOLAHAN TANAH SAWAH DI KECAMATAN WUNDULAKO KABUPATEN KOLAKA

This study was conducted from October to November 2016 at the sub district of Wundulako in Kolaka regency. It aimed to analyze the finansial feasibility of hand-traktor operation at the sub district of Wundulako in Kolaka regency and to analyze the number of optimal hand-tractor needed to cultivate farm lands at the sub district of Wundulako in Kolaka regency. The study used a simple random sampling method involving 65 out of 180 farmers who owned a hand-tractor. Data were analyzed usingthe cost ratio revenue analysis (R/C ratio) and analysis of machinery needs. Types of data used were primary and secondary data. Results of the study showed that the financial feasibility of farmers who awn a hand-tractor to rent the showed an R/C ratio of 1,,46, so renting hand-tractor in the research site was beneficial with an R/C ratio of > 1. The results of a needs analysis conducted engine then obtained optimal machine to meet the needs of tractor engines with an average of 7.74 hectares of paddy processed that as many as 13 units of the machine with the efficient level of work machine 62%, and if the level of efficiency of the engine increases to 100% then tractor optimal requirements needed 7 units with the same processing area, while the increase in the work efficiency of 200% is obtained tractor engine 4 units. Further, if all tractors work the land with a total of 503 hectares processed at the rate of efficiency of 62%, 100%, 200%, the tractor is needed to optimize the needs of the 811, 503 and 251 units.Keywords : renting of hand-tractor, needs for hand-tractor.

International benchmarking of longitudinal train dynamics simulators: benchmarking questions

ABSTRACTLongitudinal train dynamics (LTD) simulations have been playing an instrumental role in the development of larger trains, especially freight trains. LTD simulators have been reported from all around the world, but without standards or standard questions to assess the correct implementation of LTD analysis and the state of LTD studies. Under this situation, the Centre for Railway Engineering initiated the International Benchmarking of Longitudinal Train Dynamics Simulators. Eight teams involving 10 institutions from five countries across three continents have participated in the benchmark and submitted their results. This paper describes the benchmarking questions so other researchers will be able to repeat the simulations in the future and benchmark their programs against the current participating software. The question information includes train configurations and characteristics of the wagon connection system, locomotive traction and dynamic brake characteristics, resistance formula, track data, train driving controls and output requirements. The question information will also enable researchers to replicate the benchmark by providing relevant formulas, data sheets, figures and descriptions.

Field Failure Resolution of a Tractor Engine Exhaust System Using Constrained Single Objective Optimization and Stochastic Analysis

Field Failure Resolution of a Tractor Engine Exhaust System Using Constrained Single Objective Optimization and Stochastic Analysis

Steam Engines for Heavy Haulage on Common Roads — Early Trials and Early Apprehensions: 1856–1861

In 1856, a steam-powered traction engine was an exciting spectacle in a public procession. A year later, one travelled 85 miles over English roads, drawing a train of heavily loaded wagons — taking three days but showing what steam haulage could achieve. Engineers, manufacturers and entrepreneurs then vied in developing and deploying traction engines — alongside parallel developments in applying steam power to agriculture. But what were the dangers of massive steam engines working on public roads? Given the presence of very many horses on the roads, a noisy engine might cause one to rear up or bolt, throwing a rider or overturning a horse-drawn carriage. Regulation was needed! This should include equitable toll charges on turnpike roads, especially if heavy engines might cause serious damage. Legislation — eventually passed in 1861, after laborious parliamentary consideration — included speed restrictions and the possibility of banning daytime journeys in some urban localities.

Modernization of Diesel-electric Locomotive 2M62 and TEP-70 Locomotives with Respect to Electrical Subsystem

In article analysing typical electrical locomotives were manufactured with analogous control systems (2M62, TEP-70) of the entire power train and electric drive, which have a lot of deficiencies. The major deficiency was high fuel consumption. The locomotive traction force Fk= f(v) for the theoretical traction requirements must be inversely proportional to the movement speed v. This characteristics is called hyperbole, it allows optimum control of the locomotive in the entire speed range, i.e. to use the diesel engine power to its full extent. Once such locomotive traction characteristics are created, the diesel engine capacity in the hyperbole characteristics is constant. To solve this task the traction characteristics Fk= f(v) and traction generator load characteristics Ug= f(Ig) must be hyperbolic shape. In order to improve energy characteristics of diesel-electric locomotives 2M62, TEP-70, analysis of their automatic control systems was performed. Based on this, the systems which were proposed by the authors and implemented, have enabled significant reduction of fuel consumption, improved driver's working conditions, traffic safety, etc. Especially important technical tasks to be solved were to improve general reliability of locomotives, and to reduce operation costs. The authors have proposed not to use special electric machines for excitation of traction generators, but to replace them with contactless semiconductor static converters and to use microprocessor based locomotive parameters control systems.

Эволюция технических требований на колесные пары для скоростного подвижного состава

The article presents retrospective review of the technical requirements for the creation and testing of wheelset for speed rolling stock in the Soviet Union and Russia since the 1980s until now.Creation of wheelsets performed using both domestic experience and the experience of foreign companies. The domestic experience in development of technical requirements for the wheel sets accumulated during the development of domestic passenger cars of locomotive traction and electric multiple unit trains (EMU).To a large extent this contributed to the experience of operating high-speed electric locomotive CHS200 with Aurora and Troika trains as well as EMU ER200 with speeds up to 200 km/h. Then - the creation of high-speed train ES250 Sapsan with a design speed 250 km/h, and EMU ED6 with design speed 160 km/h.The most productive was the last decade, when for designing high speed rolling stock European companies with relevant experience were involved. The joint work of research institutes of JSC Russian Railways and leading European companies led to the appearance in Russia of rolling stock with the range speed up to 250 km/h (design speed of 300 km/h).Improving the regulatory framework will be the basis for the transition to the next stage in the development of high-speed transport in Russia with even higher speeds. In this case even higher reliability requirements will be presented to the running part of the rolling stock. Development experience obtained in the previous stages will contribute to this challenge.

Calculation of locomotive traction force in transient rolling contact

To represent the wheel–rail contact in numerical simulations of rail vehicles, simplified models (Fastsim, Polach etc.) are usually employed. These models are designed for steady rolling only, which is perfectly suitable in many cases. However, it is shown to be limiting for simulations at very low vehicle speeds, and therefore it does not actually allow simulation of vehicle running at arbitrarily variable speed. The simplified model of transient rolling, which involves calculation of the stress distribution in the discretised contact area, overcomes this disadvantage but might be unnecessarily complex for more simple simulations. In this paper, an approximative creep force computation method for transient rolling is presented. Its purpose is not to study the transient phenomena themselves but provide a simple and readily available way to prevent incorrect results of the numerical simulation when the vehicle speed approaches zero. The proper function of the proposed method is demonstrated by a simulation of start-up and interrupted sliding of a four-axle locomotive.

Impact of electric locomotive traction of the passenger vehicle Ride quality in longitudinal train dynamics in the context of Indian railways

Rail transport is one of the major modes of transportation in India. The dynamic performance of a railway vehicle, in terms of serviceability and safety, was evaluated on the basis of specific performance indices such as ride quality and comfort. This paper is an attempt to analyse the longitudinal dynamic model of the passenger train for the attainment of better vehicle ride quality and comfort. The modelling has been done in two phases: in the first phase, a mathematical model was analysed which was further used for the evaluation of the longitudinal dynamic forces that appear on the buffer, draw gear and fastening devices during the braking process. The second phase includes simulation of longitudinal train dynamics considering the effects of forces like rolling resistance, brake force, coupler force and the gravitational force acting externally on a vehicle for better ride quality and comfort in comparison to the traction effect on WAP-5 and WAP-7 Indian locomotives. The Sperling ride index and ISO 2631 were used respectively to calculate the ride quality and comfort using filtered RMS accelerations. Simulation results revealed that WAP-5 was better at an initial speed of 30 km.h-1 and 45 km.h-1 , whereas, the WAP-7 gave better ride quality and comfort than WAP-5 at and above the speed of 60 km.h-1 .

Tractor Power Take-Off Torque Measurement and Data Acquisition System

Abstract. With the mechanization of agricultural operations, agricultural machinery management has become an extensive research field. Sizing tractors and implements to provide the most efficient power transfer has become an ongoing process with advances in technology. Utilization of the rotational power transferred through gear trains from the tractor engine to the power take-off (PTO) shaft is one of the most efficient methods of power transfer to an implement. This research used commercially available torque sensors that were installed on a tractor PTO shaft for measuring the torque delivered to an implement. The torque sensor was calibrated using the Nebraska Tractor Test Lab’s (NTTL) dynamometer by following the Organisation for Economic Co-operation and Development (OECD) Code 2 test procedure for varying PTO loads. The calibration of the sensor was verified using the full load at varying speeds test as described in the OECD Code 2. Tractor PTO shaft torque values measured by the torque sensor were compared to the NTTL’s dynamometer torque measurement. Differences in torque values measured between the sensor and the dynamometer ranged from 3 to 23 N·m. Student’s t-test showed no significant difference between the measurements during the full load varying speed tests which demonstrated that the sensor can be mounted on the tractor’s PTO shaft for torque data collection in field operations. Keywords: Data Acquisition, LabVIEW, Power Take-off, Torque, Tractor.

Влияние новой конструкции щеткодержателей на эксплуатационный ресурс щеток тяговых электродвигателей электровозов

The article is devoted to the solution of the actual task of improving the current collector unit of collector traction electric motors of electric locomotives, which currently constitute the overwhelming majority of electric vehicles of the electric rolling stock of Russia. Based on the classical theory of commutation and using O.G. Wegner's idea on the need to establish in advance the current of the switched section equal to the current in the parallel branch of the armature into which it enters, the justification is given for the application of a new design of the sliding contact for collectors of traction motors. The article analyzes the factors accompanying the changed configuration of the brush, such as the current density and heating in a new designed brush, and also reviews comparison of areas of sparkless operation of traction motors with standard and experienced brush holders. Also, the results of operational tests on the North Caucasian Railway of the VL80 electric locomotive no. 1676 are shown, one of the traction engines of which was equipped with experienced brush holders. Experienced brush holders provided a significant reduction in brush wear. On the basis of the conducted studies, it was concluded that the decrease in wear of brushes during the operation of the engine with experienced brush holders is mainly due to a decrease in the influence of mechanical factors on the sparking. During operation, under the influence of mechanical factors, the running edges of the brushes are subject to vibration, and significant current breaks off, which cause an increased spark wear of the brushes. Using the example of a new brush contact configuration, it is shown that the brush contact, namely its design and geometric dimensions, has a significant effect on the nature of current commutation in collector traction motors.