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 / rawjaw

We know a relation speed
say,N=120f/p,speed directly
proportional to freq.In some
applications large motors
used to drive a heavy load,we
start such motors from 0 rpm
& provides initial torque(say
160%) in order to achieve
energy efficient.ok..

Is This Answer Correct ?    4 Yes 2 No



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