| 摘要 |
PROBLEM TO BE SOLVED: To provide a switching power supply device that reduces a loss than before and can stably supply a requested voltage to a load even upon an instantaneous power failure or upon a sudden load change.SOLUTION: A switching power supply device 1A includes: an insulated PFC section 2A for supplying a switching voltage Vgenerated by direct switching of an AC voltage Vvia switching elements SW, SWto a primary winding Tto generate an induced voltage in a secondary winding T; a secondary side rectifying/smoothing section 3A for rectifying/smoothing the induced voltage; and a DC/DC converter section 4 for converting the voltage output from the secondary side rectifying/smoothing section 3A to a desired secondary side output voltage V. The insulated PFC section 2A is feedback-controlled in accordance with a DC component of the secondary side output voltage V, and the DC/DC converter section 4 is a bidirectional DC/DC converter capable of both step-down and step-up operations and is feedback-controlled in accordance with an AC component of the secondary side output voltage V. |
