| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a switching power supply device capable of reducing power loss in a stationary state more than before and a method starting the same. <P>SOLUTION: An auxiliary power supply part 7 that supplies source voltage to a switching control circuit 3 and an active filter control circuit 4 comprises: a first DC current means that generates a first DC voltage V<SB POS="POST">C3</SB>by rectifying and smoothing an induced voltage of an auxiliary winding T<SB POS="POST">3</SB>; a second DC current means that generates a second DC voltage V<SB POS="POST">C4</SB>by rectifying and smoothing a sum voltage of the induced voltages of auxiliary windings T<SB POS="POST">3</SB>and T<SB POS="POST">4</SB>; a constant voltage circuit 8 that is provided in an output side of the second DC current means and generates a third DC voltage by restricting the second DC voltage V<SB POS="POST">C4</SB>to make a constant-voltage; and a stop circuit 9 that is provided in an output side of the first DC current means and stops the constant voltage circuit 8 when the first DC voltage V<SB POS="POST">C3</SB>exceeds a prescribed threshold voltage which is higher than the third DC voltage. <P>COPYRIGHT: (C)2012,JPO&INPIT |
