Answer / abhishek-gaur

in DELTA connection, phase voltage = line voltage
in STAR connection, phase voltage = 1/(root3) times line
voltage

to reduce losses, transmtng voltag should be higher, so we
use delta connectn.
bcoz star connctn wil reduce phase voltg to 0.707 times line
voltg...
thus voltg is lowered wid star ... and losses incresed
compard to delta

Answer / satheesh

to prevent zero sequence current flow in upstream side.

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