| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce the cost by reducing a rush current which is generated at recovery from instantaneous voltage fluctuation where an AC power voltage drops temporarily, and using a component which is small in tolerance of a surge current, in equipment such as an air conditioner equipped with a power unit where a large current flows. <P>SOLUTION: The power unit is equipped with: an input voltage detector which detects an input AC power voltage, a step-up circuit which boosts an AC voltage rectified from the AC voltage and supplies it to a load as a DC output voltage, an output voltage detector which detects the DC output voltage, and a control means which receives the input of the voltages detected by input voltage detector and the output voltage detector and controls the DC output voltage of the step-up circuit to be a DC output voltage set value. The control means temporarily lowers the DC output voltage set value when the AC power voltage falls under a specific voltage, and returns the DC output voltage set value to its original value, when the AC power voltage exceeds the specific voltage. <P>COPYRIGHT: (C)2010,JPO&INPIT |
