generator circuitbreaker

If you mean it's purpose, it is an overcurrent protective device. Try a google search of "circuit breaker" for more information.

i mean if i place circuit breaker b/w generator and power transformer(that is generator c.b.) and if i place circuit breaker after power x'mer then what's the advantage in either cases.

Is this a homework question, as the answer is rather obvious in both cases. It does not appear that you have a very good understanding of power transmission and distribution theory and I would rather NOT give you the answers as I do not know if you are actually involved in designing a real system. Unlike other disciplines, mistakes in this field can easily cause large loss of property and life.

In either case I would suggest that you look at various texts regarding power transmission and distribution freely available on the internet, look in your local library or consult one of your fellow students, electrical engineers, etc. The answers are all there, including the reasons behind them.

Dear Prashant.

Some utilities in India prefer a generator circuit breaker scheme as against Station Transformer scheme for sourcing startup power at the Generating Stations.

The GCBs remain open during the starting and the unit auxiliary transformers are charged from the switchyard side for startup power. Upon synchronisation, the aux power is supplied through the main Generator side.

The switchyard bays for station transformers can be saved using GCB scheme.

regards

Thank you for your valuable reply.

would you pls suggest me some link to study in detail of gcb scheme and station transformer scheme?

Try this.