what is the disadvantages of star connected alternator?
Answer Posted / amit khamesra
Neutral of the gen is grounded to detect the earthfault in
the system. If the neutral is not grounded the first earth
fault in the system shall not be very dangerous but being a
fault in the system , shall be surely rectified. If the
first EF exists and the second one happens, it shall be
very seviere and may lead to complete burning of the
winding leading to the long downtime. With neutral of the
gen earthed, various methods can be used to detect 100%
stator earthfault like 3rd harmonic based over voltage /
undervoltage .
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