A partial-resonant tapped-inductor converter with an auxiliary switch

A partial-resonant tapped-inductor converter with an auxiliary switch is proposed. The circuit construction is the same as a conventional tapped-inductor converter with active clamp circuit, but the drive timing for the auxiliary switch is different from the conventional one. As a result the output stability is improved as compared with the conventional active clamp one. Furthermore, zero current switching is achieved by a partial resonant with an auxiliary capacitor and the leakage inductance of the tapped-inductor during the on period of the auxiliary switch. The operating and performance of the proposed approach were verified experimentally by a laboratory prototype of 24 V input to 1.0 V output at 600 kHz. As a result, 2% improvement of efficiency is achieved.