Answer / ajit g. k.

From thelimited amount of knowledge I have, I guess you are
meaning to know what a "black start" is. If thats the case,
I can explain to you what black start is.
A black start is referred to starting a power station from
an OFF position without the use of external energy sources.
The external energy source is mainly the power grid. In
some cases, there comes the problem that all the power
inputs to the grid may be disconnected due to wide area
outages. In that case, the power plant uses the 'internal
power sources' like diesel generators(DGs) which may be of
a rather smaller capacity. The DGs supply power for forced
draughts, controls and other auxillary requirements in the
power station.
Hope I have answered correctly. You may have read or
deciphered the question wrong. I have not yet heard of a
black star as a phenomenon or a process whatsoever in
electrical engineering. I would like to know if there is
something of that name.

Answer / naveenkumar(eee) g.k.m

Black around star is called as black star.............. For
Ex... You can see many Black star in sky with dull colour...:)

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