Answer / sameer

AC drive speed control on basis speed=120F/P
F is frequency which is variable

Answer / manoj

ac drives control speed by frequency as well as by voltages
.

Answer / pawan

There are three parts in AC drive
1. Rectifier ckt
2. Regulator
3. Invertor ckt (IGBT used)
Using AC drive we can change the frequency of motor by
varying the frequency of input/supply voltage.

Answer / amitbamal

N=120F/P

Answer / sks

AC drives known as VFD(variable frequency drives) operate
differently from DC drives known as VSD(variable speed drives )
the most basic difference being that DC drives may have a
constant dutycycle( ON to On-Off ratio) on PWM signal but AC
drives must have a variable duty cycle throughout as they
are frequency based and can't be instantly increased or
stopped at min or max frequency.

Answer / patrice

It is a three phases speed controller
the variable frequency controller is used in the industry
especially on conveyors systems or rotating machines to
adjust the speed according to the flow of the production
It is a regulation of speed

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