Comparison Between Ac And Dc Traction Pdf
File Name: comparison between ac and dc traction .zip
- Electric Traction Systems And Their Advantages
- What is the difference between an AC motor and a DC motor?
- AC Traction vs DC Traction
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The AC alternating current Drive, also known as Variable Frequency Drive, has been the standard in industry for many years. While it has been used in locomotives for over two decades especially in Europe , it has only been recently that the price of the drives has allowed them to be used in most of the new diesel-electric locomotives in the United States. The AC drive works by converting the traction alternator output to DC direct current and reconverting it to a variable frequency AC which powers AC traction motors.
Electric Traction Systems And Their Advantages
Present scenario of Indian Railways — High speed traction, Metro, Latest trends in traction-Metro, monorail, Magnetic levitation Vehicle, Steam, diesel, diesel-electric, Battery and electric traction systems, General arrangement of D. Analysis of speed time curves for main line, suburban and urban services, Simplified speed time curves. Features of traction motors. Traction motors-single phase, Three phase, Linear Induction Motor, Comparison between different traction motors, Series-parallel control, Open circuit, Shunt and bridge transition, Pulse Width Modulation control of induction motors, Types of electric braking system. Important features of electric locomotives, Different types of locomotives, Current collecting equipment, Coach wiring and lighting devices, Power conversion and transmission systems, Control and auxiliary equipment.
A railway electrification system supplies electric power to railway trains and trams without an on-board prime mover or local fuel supply. Electric railways use either electric locomotives hauling passengers or freight in separate cars , electric multiple units passenger cars with their own motors or both. Electricity is typically generated in large and relatively efficient generating stations , transmitted to the railway network and distributed to the trains. Some electric railways have their own dedicated generating stations and transmission lines , but most purchase power from an electric utility. The railway usually provides its own distribution lines, switches, and transformers. Power is supplied to moving trains with a nearly continuous conductor running along the track that usually takes one of two forms: an overhead line , suspended from poles or towers along the track or from structure or tunnel ceilings, or a third rail mounted at track level and contacted by a sliding " pickup shoe ".
What is the difference between an AC motor and a DC motor?
Which of the following is an advantage of electric traction over other methods of traction? Which of the following is the voltage for single phase A. Which of the following drives is suitable for mines where explosive gas exists? The wheels of a train, engine as well as bogies, are slightly tapered to. Automatic signalling is used for which of the following trains?
AC traction for locomotives is a major improvement over the old DC systems. The primary advantages of AC traction are adhesion levels up to % greater than.
AC Traction vs DC Traction
A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives , electric or hydrogen vehicles , elevators or electric multiple unit. Traction motors are used in electrically powered rail vehicles electric multiple units and other electric vehicles including electric milk floats , elevators , roller coasters , conveyors , and trolleybuses , as well as vehicles with electrical transmission systems Diesel-electric Locomotives , electric hybrid vehicles , and battery electric vehicles. Direct-current motors with series field windings are the oldest type of traction motors.
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The AC Motor and the DC Motor are differentiated on the various factors like the source or the nature of the power used in the motor. The commutation process, types, starting of the motor, a number of terminals. Applications of the motor, usage of brushes and the maintenance cost of the motor. In an AC Motor , an alternating current passes through the coils. When an alternating current is passed on the electromagnets is a magnetic field is generated.
Electric motors play an essential role in almost every industry. Using the right type of motor with high-quality parts and regular servicing keeps your facility running smoothly and prevents damage to the endpoint equipment due to wear or power surges. Gainesville Industrial Electric can help your company select the right industrial electric motors and parts for your applications. Electric motors are machines that convert electrical energy—from either stored power or a direct electrical connection—into mechanical energy through the production of rotational force. The two major types of electric motors are:. Both AC and DC motors use electrical current to produce rotating magnetic fields that, in turn, generate rotational mechanical force in the armature—located on the rotor or stator—around the shaft.
The electric traction system is the most efficient of all other traction system such as steam and internal combustion IC engine type systems. It offers several benefits over other systems, including quick start and stop, very efficient, pollution-free, easy to handle and easy speed control. With the advancement of electrical drives for traction systems, this electrification of traction becomes much popular in several traction services including metro or suburban railways.
Rail transport is coming back into favour for the transportation of goods over long distances. This article takes a look at the role that electric motors play in this sector of the transport industry. Two types of locomotive are in use: the pure electric, which takes power from an overhead medium voltage catenary wire, and is limited in use to long distance runs, and the diesel engine driven locomotive which can be used for all types of operation, including shunting. This article covers the diesel locomotive.
To avoid stray current and maintain the benefit of no phase-split in the DC traction power supply system, an AC traction power supply system was proposed for the urban public transport such as metro and light rail transit. The MSS includes a single-phase main traction transformer and a negative-sequence compensation device, while the CTN includes double-core cables, traction transformers, overhead catenary system, rails, etc. Several key techniques for the proposed system were put forward and discussed, which can be summarized as 1 the power supply principle, equivalent circuit and transmission ability of the CTN, the cable-catenary matching technique, and the selection of catenary voltage level; 2 the segmentation technology and status identification method for traction power supply network, distributed and centralized protection schemes, etc. The proposed industrial frequency single-phase AC traction power supply system shows an excellent technical performance, good economy, and high reliability, hence provides a new alternative for metro and urban rail transit power supply systems.
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- Смотрите. Сьюзан кивнула. Так и есть, примерно через каждые двадцать строк появляется произвольный набор четырех знаков. Сьюзан пробежала все их глазами. PFEE SESN RETM - Альфа-группы из четырех знаков, - задумчиво проговорила Сьюзан.
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