| 摘要 |
PURPOSE: To improve power factor and power conversion efficiency by connecting a first capacitor to the output line of a bridge rectification circuit, connecting two second capacitors to the positive and negative input terminals of the bridge rectification circuit, and by supplying the switching output at a primary coil winding to the bridge rectification circuit. CONSTITUTION: A low-pass filter in normal mode consisting of a filter choke coil LN and a filter capacitor CN is provided at the rectification current path of a bridge rectification circuit D1 . Then, a first capacitor C1 A whose total electrostatic capacity is nearly equal to the electrostatic capacity corresponding to a resonance capacitor which is connected to a primary coil winding N1 for forming a series resonance circuit and two second capacitors C1 B, are provided. The first capacitor C1 A is connected to the output line of the bridge rectification circuit D1 and two second capacitors C1 B, are connected to the positive and negative input terminals of the bridge rectification circuit D1 . Then, the switching output at the primary coil winding N1 is supplied. |
