| 摘要 |
PURPOSE: To reduce electric energy absorbed by a control branch to turn a switching element on/off and electric energy consumed in a circuit and improve the efficiency of the circuit by parting the control branch with a branch which has a capacitive element. CONSTITUTION: A control branch, which has an inducing element L3 is separated with a branch D having a capacitive element. When a DC voltage source is connected to input terminals 1, 2, a high-frequency signal generating circuit P generates a high-frequency signal with a frequency (f). The high-frequency signal causes high-frequency pulse voltage with a frequency (f) on the L3 formed with a secondary minding, via a primary winding L4 in a transformer. The voltage is applied between both ends of the branch D and between a control electrode and a main electrode for a switching element S1 . A capacitance value for the D is selected to somewhat different from the resonance frequencies of the D and the L3 from the (f). In this way, the S1 is quickly turned on/off and absorbed by the D, and so the electric energy consumed in a circuit is reduced, and the efficiency of the circuit is improved. |
