Saturable reactor and lossless capacitor-assisted zero voltage transition asymmetrical PWM DC-DC converter with high-frequency transformer link

An improved half-bridge type ZVS-PWM DC-DC power converter with quasi resonant pole which makes use of a saturable reactor-assisted soft-switching technique is presented in this paper. The power converter with a high-frequency transformer link has many advantages such as lowered switching and reduced conduction losses, wide load operation range, constant frequency operation and minimized EMI. Its operating principle is illustrated and its steady-state circuit analysis is carried out. In order to demonstrate the remarkable effectiveness of the characteristic performances, experiments are carried out with a 150 W-200 kHz prototype DC-DC power converter using power MOSFETs.