| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power supply apparatus wherein the life of a capacitor for smoothing the direct current can be determined correctly, and to provide a method for determining the capacitor life. <P>SOLUTION: A detection capacitor 4 is inserted in series between a diode bridge 2 and an electrolytic capacitor 3 so that the terminal voltage of the electrolytic capacitor 3 can be detected, the terminal voltage Vd of the detection capacitor 4 is detected immediately after a DC power supply apparatus PS is introduced and before an inverter circuit 11 is started, the detection result is compared with a reference voltage Vref corresponding to the terminal voltage Vd of the detection capacitor 4 in the early stage of the electrolytic capacitor 3, and a decision is made that the life of the electrolytic capacitor 3 has expired if the terminal voltage Vd is greater than or equal to the reference voltage Vref. <P>COPYRIGHT: (C)2011,JPO&INPIT |
