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l"Trvo(2) lrl). l00kVAtransformersareconnectedinV(opendelta)banksupplying
abaianced
3q) load.
Ifthe
balanced
3
o
Ioad
is
140kW at 0.85
pflagging
and 0.85
efficiency,
deterrnine the
overload
kVA
on
each transfonner,
pf
of each secondary transfonner
and the minimum
size
in
kVAr ofa
capacitor
bank to
be
connected
across the
load so that each transformer
is Ioad 97%
of
its rated capacity.
(20pts)
2.
The
primaries
of two transfonrers are connected
to a
2300V 2-O
source.
The
secondaries are
connected
in
scott and deliver
460V,
l30kw 3 O
0.866 lagging
power
factor load. Calculate a)
tl're current
in
each transformer
winding
on
the
primary
side;
b)
the
current
in
each transformer
winding
on the secondary
side; c) rating of each transforrer.
(10pts)
3.
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