The term drive is used widely in the automation industry. A drive system may include the motor, electrical controller, gearing and pulleys. When we refer to a drive we mean the electrical controller that supplies the motor with the correct voltage and current for the desired speed and torque. 

Inverters, variable frequency drives (VFDs) and AC dirves are all terms for AC to AC power converters with a DC link. The incoming AC is converted to DC. The DC is converted to a variable output voltage controlled electronically within the drive. The parameters in the drive are set to match the motor, which enables acurate speed control and current limit protection.

Last updated on January 13, 2011 by John Gentle