can u please tell me how VFD(variable frequency) drive is
used as a energy saver....?

Answer Posted / gopalraju

The speed is purely dependent on v/f constant,until this
state the stator back emf generates z the impedence due
core magnetisation(in order to keep the unsaturated core
with in impedance window)other wise there cannot be back
emf ,hence dc component will start ie ohms law ,hence for
every one volt of increase one ampere current due to this
stator winding gets burnt .
Gopalraju

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