| 摘要 |
PROBLEM TO BE SOLVED: To practicalize a voltage resonance type converter equipped with a secondary series resonance circuit and also to cope with a wide range. SOLUTION: Secondary coils N2A and N2B are wound, and a secondary parallel circuit, corresponding to N2A, and a secondary series resonance circuit, corresponding to N2B, are made. The coupling coefficient k of an insulated converter transformer PIT is made equal to approximately 0.7 or under thereby eliminating such abnormal operation that a current flows to a switching element with the timing before the OFF period of the switching element finishes, at the time of a middle load. Moreover, as regards the constant voltage control property by switching frequency control, it is made a sharp unimodal property thereby reducing the control range of switching frequency required for stabilization. As regards power conversion efficiency, it is so arranged that a favorable property can be obtained, thus primary parallel resonance frequency fo1, secondary parallel resonance frequency fo2, and secondary series resonance frequency fo3 are set. COPYRIGHT: (C)2007,JPO&INPIT
|
