High frequency and high efficiency control of four switch Buck Boost converter
                                                                LI Hai yan, ZHU LV yuan
(1.College of Electrical Engineering, Zhejiang University, Hangzhou 310027, China;2.Zhejiang manchinery industry federation, Hangzhou 310009, China)

Abstract: Aiming at the problems that the four switch Buck Boost converter is difficult to realize high efficiency, high power density and good dynamic response in the whole input voltage range,the traditional control strategy of the four switch Buck Boost converter was summarized.There are so many problems of the traditional control strategy, such as mult mode switching, complex control to achieve soft switching. A control strategy called “mixed one mode ZVS constant frequency” of the four switch Buck Boost converter was proposed, a 300W prototype was built up for testing. The experimental results show that in the control strategy the four switch Buck Boost converter work on only one mode and can achieve zero voltage switching of the four switches in the full input voltage, the full output voltage and the full load range.

Key words: four switch Buck Boost converter; ZVS; high frequency; high efficiency