Pdf utilization of electrical energy pdf notes uee. Whatever may be source or principle of working of traction motor, all provide tractive effort characteristics to encounter train resistance and provide acceleration. In order to make the required tractive effortspeed curves for electric drives with asynchronous traction motors of acac system in dieselelectric locomotives, it is necessary to look for the optimum way of controlling traction motor. Despite their predominant use in the literature, linear approximations of such curves may fail to predict correctly key characteristics of vehicle performance eciency such as torquespeed pro. Traction energy consumption of electric locomotives and electric multiple units at speed restrictions article pdf available july 2015 with 6,234 reads how we measure reads. The control equipment is provided for manual and automatic operation. Type of electric drives, choice of motor, starting and running characteristics, speed control, temperature rise, particular applications of electric drives, types of industrial loads, continuous, intermittent and variable loads, load qualization. Tools, wires, types of wiring, accessories, lamp circuits. If electric supply is used for driving a locomotive, the system is known as electric traction.
The speed time curve is the curve showing instantaneous speed of train in kmph. The curve drawn between speeding kmhr along yaxis and timing seconds along xaxis is called speedtime curve. The paper describes a programme which has been prepared for a highspeed digital computer for calculating speedtime curves, energy consumption and motor heating for a train with given characteristics travelling on a given route. Full text of speedtime curve study of electric railway load conditions. Maximum horse power of steam locomotive is a 100 b 500 c 1500 d2500. Electric vehicle performance and consumption evaluation.
Dec 01, 2009 in order to make the required tractive effortspeed curves for electric drives with asynchronous traction motors of acac system in dieselelectric locomotives, it is necessary to look for the optimum way of controlling traction motor. Dynamics of torquespeed profiles for electric vehicles and. One is a plot of empirical data, and the other was plotted mechanically using a device developed at mit. A railway electrification system supplies electric power to railway trains and trams without an onboard prime mover or local fuel supply. Read in detail about electric traction braking system,magnetic braking,plugging,resistance braking,regenerative braking, speed time curve braking. What is an electric locomotive systems and their types in. Train movement and energy consumption electrical engineering. Typical speed time curve of a train is shown in fig 2. Basic modeling for electric traction systems under uncertainty conference paper pdf available october 2006 with 2,771 reads how we measure reads. Utilization of electrical energy and traction 2160907 chapter7.
Speed profile optimization of catenaryfree electric. The duty cycle of traction drive is explained below with the help of speed time curve and power torque time diagram. Among these curves, the speedtime curve is generally is used. Download uee notes pdf 6 unit vii electric traction ii. Traction with speed time graph steam locomotive transformer. An887 ds00887apage 4 2003 microchip technology inc. Electricity is typically generated in large and relatively efficient generating stations. Data evaluation having in mind that the monza track is a high speed circuit, achieved top speed of 340 kmh, is ordinary. From starting to the stage when locomotive attains maximum speed, the period is known as acceleration period, as the vehicle is constantly accelerated. A free powerpoint ppt presentation displayed as a flash slide show on id.
The typical speed time curve for a locomotive is shown in figure given above. Such a traction system is used in steam locomotives, ic engines, and in the maglev trains high speed trains electric traction system. Tests experiences in small radius curves of continuously. But this last offered a further expansion until which one we know today. Traction motor used for traction purpose is dc series motor, separately excited dc series motor, three phase induction motor, synchronous motor and permanent magnet synchronous motor. Essential driving mechanism of an electric locomotive is shown in fig. Oct 19, 2016 the most vital factor against electric traction is the initial high cost of laying out overhead electric supply system. The analysis prior to the preparation of the programme is given in some detail to illustrate the preliminary work necessary before a problem can be solved on one of. Which of the following is the disadvantage of electric traction over other systems of traction. The mechanics involves conversion of overhead electrical powerdieselsteam power in rail horse power to haul a train encountering acceleration, train, grade, curve resistance and similarly braking. The aspect of vector control using the asynchronous. If the speedtime curves are similar, the specific energy consumption of the curve having higher maximum speed is a higher than that of lower maximum speed. Optimization of energy consumption in electric traction system by. In other words, there is a tradeoff between how much torque a motor delivers, and how fast the output shaft spins.
Jul 31, 2014 among these curves, the speedtime curve is generally is used. The most vital factor against electric traction is the initial high cost of laying out overhead electric supply system. The traction system that doesnt use electricity at any stage of a vehicle movement is referred to as a nonelectric traction system. Which of the following is an advantage of electric traction over other methods of traction.
Discuss in detail about series parallel control of electric traction motor with example. If we assume core loss is a quadratic function of speed, it would be 1692 watts at 1200 rpm. Electric traction system requirements, terms, advantages. Speed time curve of main line service differs from those of urban and suburban services on following account a it has longer free running period b it has longer coasting period. If track faults arent eliminated speed restrictions have to be used that cause additional traction energy and time consumption of railway vehicles in operation 14, 15. In a steam locomotive electric power is provided through a battery system b diesel engine generator c overhead wire d small turbo generator. Traction with speed time graph free download as word doc. Transmission systems for heavy traction internet archive.
The graph above shows a torquespeed curve of a typical d. Unlike the monaco track were climbs and hills prevail and a top speed of 289 kmh can be achieved according to the te curves. Motor characteristics are frequently given as two points on this graph. The speed time curve is the curve showing instantaneous speed of train in kmph along ordinate and time in seconds along abscissa. Review of existing electric traction systems in india. The speedtime curve gives complete information of the moion of tt he train. Pdf basic modeling for electric traction systems under. Full text of speedtime curve study of electric railway. The curve drawn between speeding kmhr along yaxis and timing seconds along xaxis is called speed time curve. Slop of the curve at any point gives the acceleration at the corresponding instant or speed.
The aspect of vector control using the asynchronous traction. Read in detail about electric traction braking system,magnetic braking,plugging,resistance braking,regenerative braking,speed time curve braking. The locomotion in which the driving force is obtained from electric motor is called the electric traction system. Speed time, distance time and simplified speedtime curves, attractive effort for acceleration and propulsion, effective weight, train resistance, adhesive weight, specific energy output and consumption. Speed time, distance time and simplified speedtime curves, attractive effort for acceleration and propulsion, effective weight, train resistance, adhesive weight, specific energy output, and consumption. Calculation of speedtime curve for run on track with gradients and curves. Battery electric drive, diesel electric drive, etc. The speedtorque natural curve of asynchronous motor n fm is shown in fig.
It offers several benefits over other systems, including quick start and stop, very efficient, pollution free, easy to handle and easy speed control. Ppt electric traction system powerpoint presentation free. As used in mechanical engineering, the term tractive force can either refer to the total traction a vehicle exerts on a surface, or the amount of the total traction that is parallel to the direction of motion in railway engineering, the term tractive effort is often used synonymously with tractive force to describe the pulling or pushing capability of a locomotive. Speedtime curves for different services trapezoidal and quadrilateral. At base speed of 1200 rpm, output power would be 20056 watts. Full text of speed time curve study of electric railway load conditions. Electric traction docsanjeet8143 linkedin slideshare. Note that torque is inversely proportioal to the speed of the output shaft. Introduction to train movement and energy consumption 2. The torquespeed curves shown below are actual curves for the green maxon motor pictured at right used by students in 2. There are various system of electric traction existing such as electric train, trolley buses, dieselelectric vehicles and gas turbine electric vehicles.
Crest speed, average speed and schedule speed of train 4. Systems of train electrification, speedtime curves for different services, schedule speed, tractive effort, specific energy consumption, traction system auxiliaries, traction motor. For a given power, the efficiency is best at lower speed. Speed restrictions are needed because of transport safety due to railway. Quadrilateral speedtime curve pertains to which of the following services. Speed time curves for train movement the movement of trains and their energy consumption can be conveniently studied by means of speedtime and speeddistance curves. In electric traction for a trapezoidal speedtime curve. The curve drawn between speed and time is called the speedtimecurve. List the advantages and disadvantages of electric traction. Jan 18, 2019 catenary free operated electric trains, as one of the recent technologies in railway transportation, has opened a new field of research. An electric locomotive requires much less time for maintenance and repairs than a steam locomotive and such vehicles can, if desired, be kept in service for 95% or more. Consider the drive travel between two consecutive stations on a level track.
Speedtime curve of main line service differs from those of urban and suburban services. There are four distinct periods in it, acceleration period, free running period, coasting period. Suryanarayana, new age international p limited, publishers, 1996. Ppt electric traction system powerpoint presentation. The train is accelerated at the maximum possible torque, and the power increases linearly with speed.
An electric locomotive can be started at a moments notice whereas a steam locomotive requires about two hours to heat up. Among these curves, the speed time curve is generally is used. Electric traction 1701 however, the steam locomotive suffers from the following disadvantages. Splitphase ac induction motor the splitphase motor is also known as an induction startinduction run motor. Simplified speedtime curves gives the relationship between acceleration, retardation average speed, and the distance between the stop, which are needed to estimate the performance of a service at. Utilization of electrical energy pdf notes uee pdf notes. Utilization of electrical energy pdf free download uee notes uee pdf notes utilization of electrical power including electric drives and electric traction by n. The slow but continuous rotation of the energy meter even under no load is known as. Electric traction is the most efficient of all other systems and is going to be the future system to be 5312. A wellformulated solution for this problem should consider the characteristics of the energy storage device using validated models and methods. Speed profile optimization of catenaryfree electric trains.
In electric traction for a trapezoidal speedtime curve, the. This curve gives the speed at various time instance after the start of run directly. Involves use of electricity at some stage or other. Pdf traction energy consumption of electric locomotives. Electric railways use either electric locomotives hauling passengers or freight in separate cars or electric multiple units passenger cars with their own motors.
The speed time curve gives the complete information about the motion of the train. The curve may be broadly split into the following periods. Vehicles having a hydrodynamic coupling, hydrodynamic torque multiplier or electric motor as part of the power transmission system may also have a maximum continuous tractive effort rating, which is the highest tractive force that can be produced for a short period of time without causing component harm. Power failure for few minutes can cause traffic dislocation for hours. May 12, 20 tractive effort, when multiplied with speed at which the train is required to run, gives the horsepower. There are various system of electric traction existing such as electric train, trolley buses, diesel electric vehicles and gas turbine electric vehicles. System such a diesel electric drive, electric drive etc. Speed time, distance time and simplified speedtime curves, attractive effort for. Pdf traction energy consumption of electric locomotives and. System of electric traction mechanics of train movement. The application of digital computers to electric traction. For the on road test a specified trajectory in brussels is driven figure 2, including city, suburban and highway driving styles. Utilization of electrical energy pdf notes uee pdf notes unit i electric drives.
Unless the traffic to be handled is heavy, electric traction becomes uneconomical. There are various system of electric traction existing such as electric train, trolley buses, dieselelectric vehicles and. Full text of speedtime curve study of electric railway load. Catenaryfree operated electric trains, as one of the recent technologies in railway transportation, has opened a new field of research. Importance of tractive effort lies with its capability to start a train on the gradient and run it up to a speed of around 30 kmph whereas that of horse power is its ability to achieve and run at the maximum permissible speed. Special features of traction motor, methods of electric brakingplugging rheostatic braking and regenerative braking. The curve gives the speed at various instants after the start of run directly. Dynamics of torquespeed profiles for electric vehicles. What is an electric locomotive systems and their types in india. Overall efficiency of steam locomotive system is close to a 5 to 10% b 25 to 30% c 55 to 60% d 75 to 80%. Here power is applied to the vehicle from an overhead wire suspended above the. Speed time, distance time and simplified speed time curves, attractive effort for acceleration and propulsion, effective weight, train resistance, adhesive weight, specific energy output and consumption. Sketch the typical speedtime curve for main line service and to sub urban services. Nov 30, 2015 the electric traction system is the most efficient of all other traction system such as steam and internal combustion ic engine type systems.