Cycle-skipping power control for AC line-powered loads

摘要

A cycle-skipping control system uses a pseudorandom number generator with a digital comparator to produce a random binary bit stream having a data rate equal to the frequency of the AC line. The bit stream is used to turn a power control switch coupled to the AC line source on and off such that the desired fraction of full load power is provided to the load. Fine power control resolution is achieved without requiring a long control period. In addition, perceptible flicker due to pulsating AC line current is reduced, both in visibly radiant loads and in electric illumination devices in close proximity to the load.