| 摘要 |
PROBLEM TO BE SOLVED: To highly efficiently operate a switching power supply while the loss, noise, and surge of the power unit are reduced by providing a serial circuit of two auxiliary switching elements in parallel with a serial circuit of two main switching elements. SOLUTION: A serial circuit of switching elements 26 and 27 is connected in parallel with a serial circuit of switching elements 4 and 7 constituting a half-bridge circuit and diodes 30 and 31 are respectively connected in series with the elements 26 and 27 in the forward direction. A serial circuit of the auxiliary winding 13-1 of a main transformer 12 and a reactor 25 is connected between the common point of the elements 4 and 7 and that of the elements 26 and 27 so that switching energy can be fed back to a power supply through the primary winding of the transformer 13. Therefore, the switching losses of the main switching elements can be reduced by utilizing the resonant action of the switching. |
