Research On Phase-shift Zvzcs Full Bridge Converter Of Ship-charger

As development of power electronic, there are many kinds of chargers,have been improved in the market. The high-power charger is more and more popular while the requirement of high-power electrification apparatus increases. But most of the products in the market are low-power. In this paper, we design a high-power charger, it is suit for storage battery which is 24V and 100AH.There are two primary parts in the thesis. One is the research of phase-shift full bridge zero-voltage zero-current switching(PS-FB-ZVZCS) converter. Another is control technology of the converter. We detailedly analysis the soft-switching and control technique, and the key problems Duty-loss which belongs to the PS-FB converter are proposed. and study of the converter is proved by result of the simulations and experiments.More and more high power electrical power products adopt the PS-FB converter currently. so PS-FB converter becomes a hotspot of power electronic research. The phase-shift full bridge zero-voltage zero-current switching(PS-FB-ZVZCS) converter as one kinds of PS-FB converters which the advanced arm works at zero-voltage switching condition and the lag arm works at zero-current switching condition. There are so many advantages in the use convenient control, little loss of power, simple structure etc. But there also exists some problems, such as inherent duty cycle loss and the parasitic oscillation on the output rectifier diodes. In this paper, the reasons of these problems are analyzed, and the solutions are presented.We design the control circuit using UC3875 which is phase-shifted resonance-controlled chip produced by UNITRODE. There are PI-controlled voltage adjustment and current-limited functions realized by UC3875. There are protections of input/output over-voltage/inadequate-voltage and IGBT, besides constant-voltage current-limited.In the end of this paper. we achieve the conclusion that ZV-switching of advanced arm and ZC-switching of lag arm are realized correctly through an 2.4kW prototype converter. and the contol circuit works properly and fulfills all functions.