what is difference between AC VVVF drive & Dc VVVF drive
explain their working principle?

Answer Posted / nilesh m. sarate

AC vvvf drives means alternating current variable voltage
variable frequency drives its name itself indicates that
here the frequency is changing,also calld as variabl
frequency drive,converter, inverter, in which voltage
belongs to dc bus of drive & speed belongs to switchings of
IGBTs
there is only DC Drives & no Dc VVVf drve, another name is
variable speed drive, in which speed belongs to armature
voltage or field current.

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