| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage resonance converter comprising a secondary series resonance circuit in which power conversion efficiency is enhanced as a power supply circuit having a power factor improving function while decreasing the number of circuit components. SOLUTION: Abnormal operation where a current flows through a switching element at a time before ending the off interval thereof is eliminate in case of middle load by setting the coupling coefficient k of a power isolation transformer PIT at about k=0.7 or less. The switching power supply further comprises a power factor improving circuit 10 of power regeneration system where a switching output current produced in the primary winding N1 of the power isolation transformer PIT is regenerated as power and fed back to a rectification current path into which a switching diode D1 is inserted. COPYRIGHT: (C)2007,JPO&INPIT |
