Fly-Buck拓扑在数码发电机中的应用研究

Application Research on Fly-Buck Topology in Digital Generator

Fly-Buck拓扑从常规的同步整流降压拓扑演变而来,不需要额外的环路反馈便可获得隔离的电源输出,使用该拓扑可以简化低功率隔离辅助电源的设计过程。本文基于Fly-Buck拓扑电路,分析研究了Fly-Buck拓扑的工作原理,通过电路仿真证明了理论分析的正确性,并基于Fly-Buck拓扑电路设计了数码发电机的辅助电源样机,通过实验得到了二次侧的输出特性,验证了该拓扑的可行性和实用性。文中特别分析研究了当一次侧轻载或空载时Fly-Buck拓扑工作模式对二次侧输出的稳压性能的影响,电路仿真和实验结果表明:Fly-Buck拓扑工作在强迫连续模式下仍能保证二次侧输出具有良好的稳压性能,并跟随一次侧输出。

Fly-Buck topology is evolved from the conventional synchronous rectifier buck topology, and an isolated power output can be obtained without an additional feedback loop, thus using this topology could simplify the design process of low power isolated auxiliary power supply. In this paper, based on the Fly-Buck topology circuit, the working principle of Fly-Buck topology is analyzed, and then the theoretical analysis is proved to be correct by circuit simulations. Finally, a power supply prototype based on Fly-Buck topology circuit has been designed for the half-controlled bridge regulation circuit of digital generator. Experimental results including the second side output characteristics validate the feasibility and practicality of this topology. In this paper, it was especially analyzed and studied that the effects of Fly-Buck topology＇s operating mode on the second side output regulation performance when the primary load is light or empty. The simulation and experiment results show that Fly-Buck topology could ensure a good regulation performance of the secondary side output and follow the primary output by operating in forced continuous mode.