Diesel-electric locomotives have a powerful diesel “prime mover” that generates electric current for use on electric traction motors to literally turn around the axles of the train. Depending on the layout of the locomotive, it could generate either alternating or direct current using a generator driven by a diesel engine.
Charles Brown developed the first pragmatic AC electric locomotive while working for Oerlikon, Zurich, at the time. In 1981, Charles demonstrated the transmission of electricity over long distances between hydroelectric power stations using three-phase alternating current.
Modern AC locomotives better maintain traction and provide adequate grip on the rails than earlier categories and models. AC-powered diesel-electric trains are typically used to haul massive loads. However, DC-powered diesel-electric trains are still very popular because they are fairly inexpensive to build.
Italy’s railroads were pioneers around the world, introducing electric traction throughout the entire length of the main line, not just on short sections.