Millions of alternating current motors are in use throughout industry and in consumer products. Much of the power they consume, however, is wasted because electricity is fed to homes and factories at a fixed voltage level which is not required constantly by motor-driven devices and equipment, especially when in an idling mode. The cumulative power wasted, considering the millions of electric motors in service, is enormous. In order to conserve energy in aerospace electromechanical systems, where power sources must be efficiently maximized, the Power Factor Controller (PFC), was developed at the NASA Marshall Space Flight Center. The PFC senses shifts in the relationship between voltage and current and matches those factors with the loading forces on motors during their operation.
Think of the escalator when fully occupied with people it places a maximum load on the motor drive, thus requiring maximum balance between voltage and current; however, when unoccupied it does not require the same level of power. Early tests showed that the PFC could trim power usage by six to eight percent under normal motor load conditions, and by as much as 65 percent when the motor was idling. With such tremendous energy saving potential, the PFC quickly became one of NASA’s most widely adopted technologies.