Answer Posted / jignesh parmar
IN MOTOR FLUX IS DIRECTLY PROPORTIONAL TO RATIO OF VOLTAGE
Vs frequency, i.e v/f it is derived from bellow formula
e= V = 4.44*flux*no. of turn*frequency
motor speed = 120*f/p
i.e speed can be ccontrolled by variying
frequency , but if only frequency increases then flux will
also increse,& flux increse beyond some level it cause
saturation also increse of flux increse loss, so to
maintain constant flux voltagge is also incresed in same
propotion to frequency as flux is directly proportion to
ratio of voltage/frequency i.e (v/f)
and that is called as variable voltage variable frequency
drive
| Is This Answer Correct ? | 79 Yes | 17 No |
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