Answer Posted / chetan
vfd-variable frequency drive
as its name explains its function that by changing the
frequency of the power supply fed to the motor we can
change the speed of the motor as N=120f/p
where f is frequency
p-no. of poles
N- speed of motor
In vfd there are SCRs and the frequency can be changed by
controlling the firing angle of the SCRs.
VFD have alot of advantages over simple starter the bigest
one is energy saving.
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