Electric motors are the
driving force behind modern industries. From water pumps and fans to conveyors
and compressors, motors are used in almost every industrial process. However,
many applications require speed variation rather than constant-speed operation.
Over the years, engineers have developed different technologies to control
motor speed efficiently. Among these technologies, AC drives and DC drives have
played a significant role.
For several decades, DC
drives dominated the speed control market because of their excellent speed
regulation and torque characteristics. However, with the advancement of power
electronics and semiconductor technology, AC drives, commonly known as Variable
Frequency Drives (VFDs), gradually replaced DC drives in most industrial
applications.