A synchronous generator is a device that converts mechanical energy into electrical energy. The device has a rotor that spins within a stator. The rotor is surrounded by a field winding that creates a magnetic field. The stator has a series of windings that create an electric field. When the rotor spins, it creates a current in the field winding. This current is then passed on to the stator windings, where it creates an electrical current.
A synchronous generator exciter is a device that uses a magnetic field to produce an electromotive force (EMF) in a stator winding, which in turn generates a current that is used to excite the rotating field of a synchronous generator. The exciter typically consists of a rotor, a stator, and an air gap between them. The rotor is driven by a prime mover, such as a diesel engine, gas turbine, or water turbine.
When the rotor of the exciter rotates, it generates a magnetic field that passes through the air gap and induces an EMF in the stator winding. This EMF then produces a current in the stator winding, which is used to supply the field winding of the synchronous generator. The field winding, in turn, produces a magnetic field that rotates synchronously with the rotor and induces an AC voltage in the stator winding of the synchronous generator.
The voltage produced by the synchronous generator is synchronized with the grid frequency, which is typically 50 Hz or 60 Hz. The exciter ensures that the generator produces a stable and consistent voltage despite variations in the load or the speed of the prime mover. The excitation system also provides protection against overvoltage or undervoltage conditions and includes automatic voltage regulation (AVR) to maintain the desired voltage level.
