| 摘要 |
A DC-DC forward converter apparatus is described, comprising:
- a transformer (20) including a primary winding (12) comprising a first end (12a) and a second end (12b), said transformer (20) being subject to switching cycles (t on , t off ) of a voltage (V p ) on said primary winding (12);
- a first switching device (14) arranged so as to be connected between said second end (12b) and a ground node (N G );
- a second switching device (24) arranged so as to be connected between said first end (12a) and a supply node (N i );
said first switching device (14) and said second switching device (24) operating under the control of a timing associated with said switching cycles (t on , t cff ), synchronously and with a same duty cycle, according to the adjustment of the output quantities(V o , I o ) of said converter apparatus; said converter apparatus being configured to operate a reset of said transformer (20), within a switch-off interval (t off ) defined by said timing (t on , t off ), resulting in a reset voltage (V reset ) as voltage on said primary winding (V p ), and comprising means (45, 46) to reset the magnetic flux in the core of said transformer (20) at each switching cycle allowing the recirculation of a magnetization current (I m ) from said core in order to make null said magnetization current (I m ). According to the invention, said converter apparatus includes also a clamp circuit (47) comprising a capacitor (41) for storing magnetization energy as capacitor voltage (V C ) in order to generate a reset voltage (V reset ) greater than the supply voltage (V i ) of the converter and a rectification device (45). |
