High-voltage railway transformers are designed to handle voltages commonly ranging from 15 kV to 50 kV. They feature strong insulation systems to manage high electrical stresses and are constructed to be mechanically robust. These transformers must efficiently convert high input voltages to levels suitable for train propulsion while minimizing energy losses. They often include advanced cooling systems, such as forced oil or air cooling, to dissipate heat effectively. Safety features like surge protectors are also integral to their design.