Patent ID: 7898224

Claim:
A power control method using AC power, the method being capable of performing: low power control that passes only two portions of positive direction waves of each one-cycle sine wave of the AC power and only two portions of negative direction waves of each one-cycle sine wave of the AC power, which have voltage levels lower than a set reference voltage level, through a system; and high power control that does not pass only two portions of positive direction waves of each one-cycle sine wave of the AC power and only two portions of negative direction waves of each one-cycle sine wave of the AC power, which have voltage levels lower than a set reference voltage level, through the system, wherein the high power control comprises the steps of: full-wave-rectifying input AC power; setting reference control voltage for the full-wave-rectified AC power; and performing control such that only waveform portions of the full-wave-rectified AC power, which have voltage levels higher than the set reference control voltage, can be passed through a system and, thus, only center portions of positive direction waves and negative direction waves of the input AC power, which have voltage levels higher than the set reference control voltage, can be passed through the system.