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EE I41 ?ND

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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.

Two I

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