| 摘要 |
PURPOSE: To improve power factor by providing a second series resonance circuit with a lower resonance frequency than the resonance frequency of a first series resonance circuit consisting of the primary coil winding of an insulation transformer and a series resonance capacitor and supplying switching output to a rectification line via the second series resonance circuit. CONSTITUTION: A first series resonance circuit consisting of a primary coil winding N1 and a series resonance capacitor C1 is provided. Then, a second series resonance circuit consisting of a choke coil CH and a second series resonance capacitor C1 A is provided. Switching output supplied to the first series resonance circuit is supplied to an all-wave rectification line side from the connection point of the emitter and collector of switching elements Q1 and Q2 by the electrostatic capacity coupling of the second series resonance capacitor C1 A in the second series resonance circuit. Then, f0 A<f0 is established, where the resonance frequencies of the first and second series resonance circuits are f0 and f0 A, respectively. |
