Variable frequency drives application and use
In the early days of variable frequency drive (VFD) technology, the typical application was in process control for manufacturing synthetic fiber, steel bars, and aluminum foil. Because VFDs improve process performance and reduced maintenance costs, they replaced motor generator sets and DC drives. When the energy crisis occurred in the early 1970s, saving energy became a critical goal, and the use of VFDs quickly spread into large pump applications and eventually into HVAC fan systems.
Variable frequency drives compared to throttling devices
In many flow applications, a mechanical throttling device is used to limit flow. Although this is an effective means of control, it wastes mechanical and electrical energy.