What is the function of a train transformer in the electrical system of a locomotive?

A train transformer in a locomotive steps down the high-voltage power from overhead lines or a third rail to a lower voltage suitable for traction motors and onboard systems. It provides electrical isolation and voltage transformation, ensuring that the propulsion system receives the correct voltage for efficient operation. The transformer works with power electronics to control the power supplied to the motors, enabling smooth acceleration, deceleration, and speed control. It is essential for distributing power safely and reliably throughout the locomotive’s electrical system.