The rotating field of an alternator is produced by applying what type of power to the rotor?

The rotating field of an alternator is produced by applying direct current (DC) power to the rotor. When DC power is supplied to the rotor windings, it creates a steady magnetic field. As the rotor spins within the stator, this magnetic field interacts with the stator windings, inducing alternating current (AC) in those windings due to electromagnetic induction.

In the context of generators and alternators, the use of DC is crucial because it allows for a stable magnetic field, which is necessary for efficient power generation. If AC were applied to the rotor, it would not maintain a consistent magnetic field, leading to inefficient energy conversion and complications in generating a stable AC output from the stator.

Understanding this concept is essential for comprehending how alternators function and the role of the rotor's magnetic field in electricity generation.