The diesel motors in trains and some ships are run as generators at their optimal efficiency. Electric motors also can output extremely high torque (without requiring a complex transmission) which is needed to get something as massive as a train or ship moving from dead stop.
Why are locomotives Electric?
Main generator excitation increases, increasing its electrical output. Each traction motor (C) is directly geared to a pair of driving wheels. The use of electricity as the “transmission” for the locomotive is far more reliable than using a mechanical transmission and clutch.
Why train engines are not turned off?
Another reason for not turning off diesel train engines, lies in the engine itself. … It is also interesting to know that while diesel locomotives are idling, fuel consumption is more than when the train is moving. This is because, while idling, the batteries are being charged, and the air compression is in operation.
Do trains use electric motors?
Today’s advanced electric locomotives use brushless three-phase AC induction motors. These polyphase machines are powered from GTO-, IGCT- or IGBT-based inverters. The cost of electronic devices in a modern locomotive can be up to 50% of the cost of the vehicle.
Why are DC motors used in train not ac motors?
DC motors are used on trains is because of their high torque and good speed control. Compared to AC motors, DC motors can provide industry applications with a fine balance of strong starting torque and controllable speed for seamless yet precise performance.
Do locomotives have toilets?
Yes, all over the road locomotives, and local use locomotives are equipped with toilets in small rooms in the front hood area of the locomotive. … Some have an air pressure assisted flushing system using fresh water similar to an airline toilet.
Which is better diesel or electric locomotive?
While more costly, the electric locomotives are faster, mainly because they accelerate faster than diesel trains and have higher maximum speeds.
What is the longest train ever recorded?
What is the longest and heaviest train ever operated in the world? The world’s longest and heaviest train operated on June 21, 2001, between Newman and Port Headland in Western Australia. The train operated 170 miles (274 km) with 682 loaded iron ore cars.
How much does a locomotive engine cost?
So, How much do locomotives cost? A diesel locomotive could cost from $500,000-$2 million. While an electric locomotive could cost more than $6 million. Price depends on whether it is powered by AC or DC traction, how much horsepower it has, or what electronics it is equipped with.
Why is one locomotive always backwards?
Making all that commerce move down the track are train locomotives. But some of the locomotives face backwards as they move down the tracks, seeming to one 2News viewer that they are being inefficiently dragged down the tracks. … Thus, the direction of the locomotive makes no difference to efficiency or safety.
Are locomotives AC or DC?
Modern AC locomotives tend to have better traction and offer better adhesive to the tracks than earlier models. AC diesel-electric trains are most commonly used for carrying heavier loads. However, DC diesel-electric trains are still very popular as they are relatively cheaper to manufacture.
Are diesel locomotives AC or DC?
In a diesel–electric locomotive, the diesel engine drives either an electrical DC generator (generally, less than 3,000 horsepower (2,200 kW) net for traction), or an electrical AC alternator-rectifier (generally 3,000 horsepower (2,200 kW) net or more for traction), the output of which provides power to the traction …
Are train motors AC or DC?
A modern railway 3-phase traction motor is controlled by feeding in three AC currents which interact to cause the machine to turn. The three phases are most easily provided by an inverter which supplies the three variable voltage, variable frequency (VVVF) motor inputs.
Why regenerative braking is not possible in DC motor?
In case of DC Series motor, as the speed of Motor increases, the armature current and hence the field flux will decrease and therefore Back emf E can never be greater than the supply voltage V. Therefore, Regenerative Braking is not possible in DC Series Motor.
Which DC motor is used in train?
Traditionally, these were series-wound brushed DC motors, usually running on approximately 600 volts. The availability of high-powered semiconductors (thyristors and the IGBT) has now made practical the use of much simpler, higher-reliability AC induction motors known as asynchronous traction motors.
Which motor is most suitable for electric traction?
3. AC Series Motor: Many single phase ac motors have been developed for traction purposes but only compensated series type commutator motor is found to be best suited for traction. Single phase induction motors have been abandoned as they are not capable of developing high starting torque.