Why induction motor is used in traction?

This is the most important feature of traction motor provides opportunity for saving on energy but also smoothness in braking, saving on wear and tear in mechanical braking system. An Induction motor works as a generator if mechanical speed is more than the synchronous speed.

Which motor is used for traction purpose?

The DC motor was the mainstay of electric traction drives on electric and diesel-electric locomotives, street-cars/trams and diesel electric drilling rigs for many years. It consists of two parts, a rotating armature and fixed field windings surrounding the rotating armature mounted around a shaft.

Why do induction motors have slip?

Motor Slip is Necessary for Torque Generation

These primary windings are connected to a voltage source to produce a rotating magnetic field. Three-phase motors with windings spaced 120 electrical degrees apart are standard for industrial, commercial and residential use.

What is traction motor control?

A speed control system of traction motors for electric vehicles comprises a traction motor for causing an electric vehicle to run, a D.C. supply source for supplying voltage to the traction motor, a chopper for chopping the voltage fed from the D.C. supply source to the motor, and a chopper control circuit for …

IT IS INTERESTING:  How much transmission fluid does a 2006 Ford f150 take?

Why DC is used in trains?

Direct current, either directly supplied, or converted from AC onboard a train, is the most commonly used. … The equipment in the DC traction system is less costly, lighter, and more efficient than an AC traction system. It also causes no electrical interference with nearby communication lines.”

Which motor is used in metro train?

THREE PHASE SLIP RING INDUCTION MOTOR has been used in DELHI METRO. Dc series motor is ideal for traction but the maintenance cost of which is very high also needs the conversion and smoothening of AC voltages.IM has less maintenance,high starting torque, cheap etc.

Why 25kV is used in railway traction system?

The main reason for 25kV voltage used in railway is, that 25 kV AC more economical than 1.5kV DC voltage system. Since 25kV voltage system has higher voltage, the higher voltage reduces the current flow through conductor; this reflects to reduce the conductor size. The cost of the conductor gets less.

What happens if the slip of induction motor is 1?

Slip = 1, means that rotor is stationary. Negative value of slip in induction motor can be achieved when the rotor speed is more than the synchronously rotating magnetic flux. … Slip more than 1 implies that, rotor is rotating in a direction opposite to the direction of rotation of magnetic flux.

What is normal slip of an induction motor?

Because of this speed difference, the motor rotates at a speed slightly slower than the synchronous speed. Slip is normally expressed in percentage. Slip of a power induction motor is 2 to 3% when the motor is operated under the rated load.

IT IS INTERESTING:  What vehicles have start/stop technology?

How does an induction motor start?

When the supply is connected to the stator of a three-phase induction motor, a rotating magnetic field is produced, and the rotor starts rotating and the induction motor starts. … At the time of starting, the motor slip is unity, and the starting current is very large.

What is the need for traction motor control?

The control of traction motors for starting and for smooth acceleration is very much essential to avoid damage to the motors. The control equipment is provided for manual and automatic operation. Usually a master controller is used for the purpose.

How do traction motors work?

The DC motor works because, simply put, when a current is passed through the motor circuit, there is a reaction between the current in the field and the current in the armature which causes the armature to turn. The armature and the field are connected in series and the whole motor is referred to as “series wound”.

Which method is best for series traction motors?

Explanation: Series-parallel control method is superior to the rheostatic control insofar as efficiency is concerned. However, it is limited to two speed steps. The method is commonly employed for speed control of series traction motors.

Which is safer AC or DC?

A.C. is More Dangerous than D.C.

A.C. is said to be four to five times more dangerous than D.C. For one thing, A.C. causes more severe muscular contractions. For another, it stimulates sweating, which lowers the skin resistance.

Why DC is not used in home?

Large transformers are used to run transmission lines at high voltages in order to keep losses to a minimum. But high voltage is dangerous, particularly to life, so bringing it into a house would not be an acceptable risk. … DC arcs do not “quench” as easily (because voltage does not go through zero).

IT IS INTERESTING:  Can you use magic eraser on windshield?

What is more efficient AC or DC?

1. DC power is significantly more energy efficient than AC power. DC motors and appliances have higher efficiency and power to size characteristics. … The greater efficiency resulting from recent developments in DC converter technology allows improvements in electricity delivery over long distances.

Car service