| 摘要 |
<P>PROBLEM TO BE SOLVED: To surely protect an apparatus by quickly detecting the interlayer short of a linkage reactor or a step-up reactor, with a low-cost configuration which uses no multiple temperature sensors. <P>SOLUTION: A filter circuit 19 comprises a high pass filter or a band pass filter, and extracts a ripple component from a detection current Id of a current detector 7 which is outputted to a ripple abnormality judging circuit 20 as a ripple current signal Sr. The ripple abnormality judging circuit 20, when inputted with the ripple current signal Sr, judges whether its peak value exceeds or not a pre-set judging reference value Aj. If exceeded, it judges that a ripple abnormality occurs, and outputs [1] signal as an abnormality decision signal Sa to a gate control circuit 11. <P>COPYRIGHT: (C)2004,JPO |
