can anyone describe about the EX2100e excitation system. Actually my question is why there are three application in EX2100e excitation system?

1) Rotating Dc Regulator
2) Brushless Regulator
3) SCT/PPT Regulator

what are the main differences in between them?

 

mhm,

The exciter regulator ("controller") of the EX2100e is usually almost always the same equipment, but the type of exciter can vary greatly from generator to generator. Exciters, regardless of type, have the same requirements: to control the generator terminal voltage (ultimately) and in the process control the voltage/current applied to the generator rotor (directly or indirectly).

Smaller generators typically use rotating or brushless exciters, which are less expensive and don't usually require as much voltage current from the exciter regulator. These types of exciters don't usually have brushes and slip-rings which also reduces the cost and maintenance, but they don't always have the best response to some fault conditions.

The SCT/PPT system is a sophisticated type of exciter that derives the power for the generator field from SCTs (Saturable Current Transformers) and/or PPTs (Power Potential Transformers) which are installed on the generator output phases. This type of exciter has several advantages, including the ability to ride through some serious "close-in" faults and continue to provide power (important in some applications/conditions) but has a lot of "auxiliary" equipment (the SCTs and PPTs are large pieces of equipment, and feed large rectifier banks to produce the DC to be applied through brushes and slip-rings to the generator rotor).

Again, the "brains" of any exciter control system (regulator; controller) have basically the same function--but depending on the type of excitation system used on a particular generator there will be differences in the auxiliary equipment and in some cases the exciter regulator will also have more I/O--but still perform the same basic function: regulate the voltage/current applied to the generator rotor to maintain the desired generator terminal voltage (and possibly a desired VAr or power factor setpoint).

The above description is for the AC or Automatic exciter regulator function of an excitation system. There is a DC or Manual function that is an internal loop which most all exciter regulators have as well, some are available as "back-ups" to the AC/Automatic regulator function, some aren't. I believe the EX2100e makes both regulator functions available to an operator, if so configured.

If you want to know more about various types of exciters, you can use your preferred Internet search engine. The EX2100e is designed to be able to work with just about any kind exciter, from brushless to rotating to static to SCT/PPT types.

Hope this helps!

 

Dear CSA

Thanks for your reply.