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.
What is the suitable DC motor for electric traction?
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.
Why is series motor used in traction?
Abstract: DC series motor has been the most used solution for the traction of locomotives, trolleybuses, trams and others, characterized by a speed and torque control using additional resistances, which means a low efficiency, electromechanical contactors, high maintenance costs, dynamic braking in resistances.
Are locomotives AC or DC?
All in all, the AC traction locomotive offers about twice the amount of adhesion as a DC unit. Therefore, a modern lightweight AC locomotive such as the RX500 can provide as much or more tractive effort than an old style DC unit like the SW1200 which weighs 60% more.
For which application a DC motor is preferred over an AC motor?
Because DC motors have higher starting torque compared to AC motors, they are preferred for applications like electrical traction. They are considered ideal for dealing with heavy loads for starting conditions in machines such as locomotives and cranes.
Why induction motors are not suitable for electric traction?
Three phase induction motor is not suitable for traction purposes because traction motor requires high starting torque, for urban and sub urban lines, the acceleration (speed at starting) should be high and simple speed control is required to start and stop the motor easily.
Which motor is preferred the most for traction purpose Why?
Why are the DC motors preferred for traction applications? Explanation: DC motors are used for traction as, according to the characteristics of DC motors speed is inversely proportional to torque and square of armature current as well, if linear magnetization is concerned.
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.