Traction Transformers-An Overview

Traction Transformers are used in locomotives to step down the voltage from the overhead power lines.  These transformers are similar to power transformers.  However, they can be designed to function at different frequencies from 16 2/3  Hz to 50 Hz.  The size of the core will vary depending on the frequency the transformer is designed for.  At lower frequencies, a higher cross section of the core is required.Traction Transformer

Cooling is carried out by different means such as through the use of silicone or mineral oil. 

These transformers have a heater winding if they are operated at low temperatures.  Traction Transformers will also have multiple traction windings. They may also have auxiliary windings for other circuits. 

Traction Transformers are generally roof mounted.  Some locomotives have transformers below the chassis as well.

(image courtesy : Siemens)