| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a switching power supply device for a bidirectional operation, capable of reducing a surge voltage which is caused by an inductor. <P>SOLUTION: A switching power supply device 1 includes a step-down operation mode which steps down a first DC voltage to generate a second DC voltage, and a step-up operation mode which steps up a second DC voltage to generate the first DC voltage. It includes a transformer 30 containing a primary side winding 31 and secondary windings 32A and 32B, a primary side switching circuit 10 which converts the first DC voltage to an AC voltage in the step-down operation mode, a secondary side switching circuit 20 which converts the second DC voltage to an AC voltage in the step-up operation mode, an inductor Lch which constitutes a smoothing circuit for generating the second DC voltage in the step-down operation mode, releasing means (a resistance element Rp) which releases the energy accumulated in the inductor, and one or more release switches (a switching element SW23) for controlling the releasing means. <P>COPYRIGHT: (C)2012,JPO&INPIT |
