Application of soft-switching technology in four switch Buck-Boost circuit

In this paper, a four switch Buck-Boost converter with soft-switching circuit is proposed (S-FSBB converter). The zero-current turn-on and zero-voltage turn-off at buck mode and boost mode are realized in the four-switch Buck-Boost (FSBB) converter by adding some additional passive components, which reduces switching losses. The circuit loss of S-FSBB converter and FSBB converter are calculated. Simulation and experiment result shows that, comparing with FSBB converter, S-FSBB converter can reduce switching noise and voltage stress, and achieve higher conversion efficiency.