Generator Voltage Control

In synchronous generators, the exciter delivers DC power to the rotor's field winding.

Older models use a rotor-driven DC generator as the exciter, while modern ones use static or brushless exciters.

Static exciters rectify AC power from the generator terminals or bus and supply it to the rotor.

Brushless exciters use an inverted synchronous generator, rectifying AC power from armature windings to the field winding.

Type 1 exciters have a shaft-driven DC generator and a voltage regulator that adjusts the field current based on the terminal voltage.

In wind turbines, voltage control varies by exciter type. Type 1 lacks direct control, while Type 2 uses resistance control to maintain constant power output during wind gusts.

Type 3 exciters control reactive power, keeping it constant or varying with real power output.

Block diagrams visualize generator-voltage control in transient stability programs.

High-gain, fast-responding exciters increase field voltage during short circuits, improving transient stability.

Block diagram equations compute the transient response.