Title:
HIGH-POWER FACTOR SWITCHING POWER SUPPLY
Document Type and Number:
Japanese Patent JP3723947
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a switching power supply wherein soft switching is carried out so that input alternating current is sine waves and inrush current does not flow when power is applied.
SOLUTION: The switching power supply is characterized in that: a switch M1 is subjected to soft switching so that stable resonance is caused in the circuits of transformers T1 and T2 by charging and discharging currents for capacitors C1 and C2. Thus, input alternating current is passed even in a period for which a voltage zero point is passed and the alternating-current voltage is low. Input alternating current in sine waves whose power factor is close to 1 is passed. Thus, power stored in the transformer T2 during the soft switching is outputted to the secondary side to enhance the efficiency. Further, inrush current is prevented from flowing when power is applied.
Inventors:
Hiroo Arikawa
Masaya Enao
Masaya Enao
Application Number:
JP2003068598A
Publication Date:
December 07, 2005
Filing Date:
March 13, 2003
Export Citation:
Assignee:
SOC Co., Ltd.
International Classes:
H02M3/28; H02M1/42; (IPC1-7): H02M3/28
Domestic Patent References:
| JP2001275352A | ||||
| JP56066168A | ||||
| JP9093946A | ||||
| JP7015967A |