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The aim of the article is to find out the impact of the increase in the force in the upper link of a three‑point hitch on the performance parameters of the tractor set Claas Arion and the carried plough Pöttinger equipped with a traction roller and the cultivator Väderstad. During aggregation of the tractor with the plough with an average increase in the force in the upper link of a three‑point hitch by 25 kN, a decrease of slippage in average by 8.25 %, a decrease in fuel consumption by 1.875 ml / m³ and an increase in effective performance by 0,225 m³ / s were achieved. During aggregation of the same tractor with the carried cultivator with an increase in the force by 40 kN, an average decrease in slippage by 2.64 %, a decrease in effective fuel consumption by 2 l / ha and an increase in effective performance by 0.6 ha / h were achieved. The changes in the observed parameters were demonstrably influenced by the change in the force in the upper link, which was more significantly shown during the aggregation of the tractor with the plough equipped with a traction booster. [ABSTRACT FROM AUTHOR]

Copyright of Technical Transactions / Czasopismo Techniczne is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Technical Transactions / Czasopismo Techniczne is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the experimental validation of a novel cooling concept applied to a high-speed switched reluctance machine topology for traction applications. By circulating the coolant between the coils and the stator poles, the winding and the stator iron are virtually thermally decoupled. A number of test motorettes are used to demonstrate the potential of the cooling concept at current density values up to 27 A/mm2 continuously. The measurements are also used to validate a thermal model of the machine, and further improvements of both the model and the experimental setup are proposed. [ABSTRACT FROM AUTHOR]

In the second half of the 19th century, the area known as Lezíria, in Portugal, started to use portable steam and traction engines in agricultural production. Out of more than a hundred original examples, all of them manufactured in England, little more than a dozen survive today, with different levels of preservation. This article studies these for the first time through an archaeological perspective, identifying their use and importance in different agricultural activities in the production of goods such as olive oil. [ABSTRACT FROM AUTHOR]

In this study, the simulation of an electrification system and traction power system of a 25 kV AC feed railway line was performed with all its subcomponents using MATLAB/Simulink. The power ow theory was used while modeling the railway electrification system. The transformer substation, catenary, rail, and vehicle were modeled together with the operational data. This model is used in order to determine the number of transformers, the distance of feeding centers, and the frequency of trips. The optimum design of electrification projects depends on these criteria. A dynamic structure was created with a new algorithm developed for vehicle load characteristics. The simulation of the electrification system and traction power system is performed before the analysis stage, together with the vehicle and other design parameters. This analysis is performed for the best performance of the systems. In this study, the power simulation of the railway was conducted for three different operation scenarios using MATLAB/Simulink. [ABSTRACT FROM AUTHOR]

significant role is played by traction control system (TCS) in road vehicles, because slip occurs during driving on wet road or snowy surface. However, it is very dangerous to drive on the icy or snowy road without traction control system, because in that condition the vehicle can lose its path. In such condition, to control a vehicle is very difficult task for drivers. Drivers can regulate easily the traction torque of vehicle driving on difficult surface by using TC system. It also makes our journey safe. Owing to such system high way automation system can be made safer. In high way automation system it plays very crucial role as well. Therefore, TCS estimates the slip of each wheel and distribute traction torque between the wheels. Thus, it makes better the longitudinal performance of a given vehicle. In simulation it is analyzed that traction control system plays important role in road vehicles. So, there are four different cases of traction torque distribution shown while driving on different road conditions. Therefore, traction torque is distributed with respect to the slip of each wheel. In case of increasing slip in either of the wheel the traction torque will be distributed accordingly. Actually, in the given system a torque is distributed corresponding to the slip of each wheel. When a wheel loses its traction then traction control system activates and minimizes the torque of the given wheel. In contrast, it will involve maximum traction torque to opposite wheel. Similarly, it can be observed that traction torque will be reduced to the wheel which is spinning. Control system will observe the whole phenomenon of slip and distribute traction torque either high or low according to the value of slip. However in this research work cost effective and very simple techniques are adopted. [ABSTRACT FROM AUTHOR]

The harmonic currents injected by high speed electric trains cause not only the pollution of power quality (PQ), but can also excite harmonic resonance in the traction power supply system (TPSS) of high speed railway (HSR). It is essential to build a proper harmonic distribution and prediction model for high speed electric trains. This paper presents an approach to obtain the probability density of harmonic current based on a non-parametric Kernel density estimation method, which can describe the probability distribution characteristics using a data-driven mechanism. A prediction algorithm for harmonic current based on confidence intervals, which can simulate harmonic current injection using a continuous sampling method, is presented in this paper. The new high speed CRH380AL electric multiple units (EMU) are used to illustrate the method. The results show that the proposed approach and algorithm can be useful for harmonic source simulation in harmonic power flow calculation and PQ assessment. [ABSTRACT FROM AUTHOR]

The experiment was conducted on IGKV research farm in wet puddle condition in April month of 2015. The wet tillage practice was carried out by power tiller cage wheel attached with five tines cultivator. Paddy production increases by puddling of soil before transplanting. Cage wheel is an important traction device for any prime mower. The lug is wing provided in cage wheels which interact with the wet soil to churn the soil .The cage wheel 730 mm diameter with 30°, 45° and 60° lug angle and three different diameter of 73 mm, 680 mm and 780 mm of 30° was tested at 0 to 50 mm, 50 to 100 mm, 100 to 150 mm and 150 to 200 mm, depth of water level in wet land field. The result was found that cage wheel C1 of 30° lug angle with 730 mm diameter give better performance than other cage wheel. The cage wheel showed the best result in 50-100 mm water level in respect to maximum tractive efficiency was found in the range of 73-78% at 996 N to 1009 N draft and drawbar power was in the range of 478.08 W to 484.32 W. While maximum drawbar power was (523.16 to 555.28 W) was observed at 0 to 50 mm water level. Therefore cage wheel of 30° lug angle with 730 mm diameter was found suitable for wet land paddy field condition. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A Traction Control System (TCS) is used to avoid excessive wheel-slip via adjusting active brake pressure and engine torque when vehicle starts fiercely. The split friction and slope of the road are complicated conditions for TCS. Once operated under these conditions, the traction control performance of the vehicle might be deteriorated and the vehicle might lack drive capability or lose lateral stability, if the regulated active brake pressure and engine torque can't match up promptly and effectively. In order to solve this problem, a novel coordinated algorithm for TCS is brought forward. Firstly, two brake controllers, including a basic controller based on the friction difference between the two drive wheels for compensating this difference and a fuzzy logic controller for assisting the engine torque controller to adjust wheel-slip, are presented for brake control together. And then two engine torque controllers, containing a basic PID controller for wheel-slip control and a fuzzy logic controller for compensating torque needed by the road slope, are built for engine torque control together. Due to the simultaneous and accurate coordination of the two regulated variables the controlled vehicle can start smoothly. The vehicle test and simulation results on various road conditions have testified that the proposed method is effective and robust. [ABSTRACT FROM AUTHOR]

This paper investigates a method to increase fuel economy of motors for an electric vehicle (EV) traction system. The low-torque region of an EV motor is frequently used in everyday urban driving and in fuel economy measurement. Pulsewidth modulation (PWM) carrier harmonic iron loss accounts for a high percentage of total loss for EV motors in this region. This paper reveals the relationship between phase current and carrier harmonic iron loss for a permanent-magnet synchronous motor (PMSM) in the low-torque region. Thus, a novel carrier harmonic loss reduction technique is proposed and applied to two sets of three-phase windings for a concentrated winding PMSM. The loss is successfully reduced in a 70-kW EV motor as well as a two-dimensional finite-element method (2-D-FEM) calculation. The efficiency of the developed motor is calculated and compared with that of a conventional motor in the JC08 mode driving cycle. [ABSTRACT FROM PUBLISHER]

Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently, automotive traction systems are increasingly being revised from combustion engine drives to electric propulsion. The high power cables of electric vehicles are routed close to various communication, sensor, or control units. This circumstance results in a tightened challenge for the developing engineers, who need to ensure the electromagnetic compatibility of these miscellaneous and adjacent systems. A trial-and-error approach in the development process of electromagnetic interference filters can only be avoided if the influence of the network impedances within the high voltage traction harness on conducted RF disturbances is known. This contribution presents the current methodology of determining the conducted emissions of power inverters for electric driven cars. It highlights the differences between the traditional low-voltage cable wiring and novel high-voltage traction harnesses, and their impact on the network impedances. An adaption of the line impedance stabilization networks used recently to the characteristic impedance of the high-voltage cables applied shows the influence of termination mismatch on conducted emissions within the traction harness. High-voltage components employed in a car are usually supplied by a traction accumulator battery, which acts as transmission line termination. The influence of a battery's input impedances on disturbances within a component level EMC test setup is shown. [ABSTRACT FROM PUBLISHER]

Tractors play an important role in agricultural mechanization. A repairable mechanical system (as agricultural tractor) is prone to deterioration or repeated failures. In this study, the owners of three hundred tractors, which include Massey Ferguson (MF285 model and MF399 model), John Deere (JD3140 model) and Universal (U650 model), were interviewed, from five regions of Khouzestan Province. A regression model was used to predict the tractors failure rate. The machine failure pattern was carefully studied and key factors affecting the failure rate were identified in these regions. The data obtained from farm records valid by using questionnaire was separated into two groups according to how those tractors were stored. Results showed that the majority of recorded failures were observed in the electrical system for all tractors. According to the results of the research, different storage policies significantly affected the failure rate for MF285, MF399 and JD3140 tractors (63%, 55.5% and 61.6% respectively), whereas inside storage of U650 tractors slightly decreased the failure rate (7.4%). Also, closed storage condition was found to reduce annual repair and maintenance costs by 33.6%, 33.6%, 29.6% and 2.56% in comparison with open air storage condition for the study tractors respectively. The observational estimate showed that all tractors were in the wear out period under outside storage conditions, against inside storage had a considerable effect on the failure rate of MF285, MF399 tractors and they were commonly in a randomized breakdown period within their useful life, JD3140 tractors were in the beginning of wear out period, but U650 tractors were in the wear out period for both storage conditions. Therefore, it can be said that by storing the tractors out of the weather conditions slowly exposed by failure and breakdowns, especially in warm climate and presented of dust haze phenomenon. [ABSTRACT FROM AUTHOR]

In the present investigation a contribution is offered in order to improve the knowledge of the influence of both speed and tyre type on a medium power tractor vibrations. The vibrations transmitted from the ground to the driver's seat of a ballasted wheeled tractor of medium power, equipped with a front suspension axle and a suspended cab, have been measured and analyzed. Two different tyres, namely, types A and B, at two different forward speeds, 11.1 and 13.9 m s-1, have been experimentally tested, during the simulation of the front agricultural implements transportation on a rectilinear plane tract of a conglomerate bituminous closed track. This work has been done by applying standards recommended by ISO 2631/1, 1997. Results were obtained on the basis of the measurement of both the root-mean-square (RMS) acceleration and the frequency analysis, conducted for any axis on the tractor rear axle and on the operator seat. In particular, different results were obtained for the two tyres and along all the axes. Furthermore, the acceleration was not strictly proportional to the forward speed increases. [ABSTRACT FROM AUTHOR]

An investigation was carried out on tractor seat design for better operator comfort during operation. The project objectives were mainly aimed to increase the ride comfort by improving the seat suspension which is used in Indian tractors. Tests were conducted for haulage operation and also for field operation. During haulage operation tests were carried out on existing seats used in Indian tractors with three new selected suspension systems of the two most selling models of MF 241 and MF 1035. The model MF 241 equipped with a existing seat is mostly used in India, while the model MF 1035 consists of exported benchmark seat (for comparison) which is a seat whose suspension appeared to majority of operators is used for more comfortable and rest three selected seat suspensions were replaced to same existing seat used in India. Tests were conducted with three different operators representing 5th, 50th and 95th percentile (SM1, SM2 and SM3) of the population of India. Best suspension system was selected, based on weighted RMS acceleration awx, awy, awz for each axis and the acceleration vector sum av performance. The values of weighted RMS acceleration awx, awy, awz, and acceleration vector sum av of different suspension systems were compared with exported benchmark seat as well as existing seat mostly used in India. The changes in the vibration peak along with speed were compared graphically. It was observed that the SP2 suspension gives better result among three selected suspensions. The results were comparable with exported benchmark seat in higher speed range which was available in developed countries. [ABSTRACT FROM AUTHOR]