If you have electric AC motors in your facility, then you have the opportunity to upgrade your processes with variable frequency drives. This applies to nearly any AC motor. It does not matter if it runs industrial equipment, a pump controller, or alters pressure and flow control for another piece of equipment.
The VFD works by allowing direct control of your electric motors. What this means is that it can run an AC motor at variable speeds or help the motors ramp up their speed to provide a smoother start up.
This process works by the VFD adjusting the frequency and voltage sent to the motor to alter the RPMs of the motor itself. This procedure requires the VFD to convert the voltage two times before it goes to the motor.
First, it takes AC power and converts it to a DC current through a diode. Then, with a capacitor, it cleans up and controls the voltage. Finally, the VFD uses transistors to convert it back to AC before sending it on to the motor. These stages are what allows the variable frequency drive to adjust the speed of the motor so precisely.