My friend has
faced this
question! I
don't know
clearly. So
please anyone
give me the
correct and
short answer to
this question?
What is variable
frequency drive?
Types, what is
star to delta?
Why this
arrangement
necessary?

Answer Posted / amit shetkar

see firstly vfd is basically used mainly for 2 purpose i.e to
protect electrical motors & for speed control.
& now about that star delta arrangement it used before motor
in that star connection is used to give smooth start to motor
& when motor achieve it's speed so to maintain that speed
delta connection is used

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