| 摘要 |
<P>PROBLEM TO BE SOLVED: To eliminate occurrence of rush currents at re-start of switching by discouraging that switching of an active filter stops due to fluctuation of a load, in a power supply comprising the active filter. <P>SOLUTION: An AC power source 1 is converted to a DC voltage by a rectifier circuit 2 which is made into a prescribed DC voltage with an active filter 3. The prescribed DC voltage is smoothed by a smoothing capacitor 4 which is applied to a load 5. A control circuit 11 detects the temperature around the load 5 using a detection signal from an ambient air temperature detection circuit 10 in advance. If the detected ambient temperature is equal to or higher than a prescribed value, the target value of the active filter 3 is set to be higher than an normal one since load fluctuation is large. Thus, an output DC voltage does not exceed a target value, not stopping control of the active filter. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
