Why one of the generators has better regulation than the other?

Question

Why one of the generators has better regulation than the other?

Answer 1

You may be referring to  properties know as speed droop and/or voltage droop.   These are negative feed backs that r****d the the spped and/or voltage of a generator as more load is added to the generator.

This is necessary inorder to balance load between generators so that one or more generators attempt to take more load than the others. If one generator took more load it would either become overloaded OR cause another generator to become unloaded to a point that it could be motorized and start consuming power rath than producing it.   In either case the is would be possible to have generators trip off line, possible in a cascaded trip.

One one generator in the parallel group need be operated without droop so as to be the freq and voltage standard. The remaining generators added must have some amount of droop to prevent thme from hogging the load.