Patent ID: 7711502

Claim:
A power switching control apparatus having an A-phase switch, a B-phase switch and a C-phase switch connected with the A-phase, B-phase and C-phase of a three-phase AC power circuit, respectively, for controlling the individual phase switches independently of one another, comprising: making operation time information detecting means for outputting making operation time information ITA, ITB and ITC representing the individual making operation times of said A-phase switch, said B-phase switch and said C-phase switch, respectively; and switching control means for controlling the making instants of said A-phase switch, said B-phase switch and said C-phase switch on the basis of said making operation time information ITA, ITB and ITC, wherein said making operation time information detecting means outputs the making operation time information of at least one of said individual phase switches on the basis of the motion of the movable contact of said phase switch, and outputs the making operation time information of at least another one of said individual phase switches on the basis of the phase current of said phase switch.