改进型双管正激电源变换器的仿真及设计

Design and simulation of enhanced two-transistor forward power converter

双管正激变换器作为一种主要的功率变换器,其开关电压应力低,可靠性高等优点,本文对传统双管正激电路做出改进,提高电路的效率。文章对改进后电路的工作过程及具体应用时遇到的问题做出了分析,给出了解决方案。与传统电路相比,改进后的电路控制电路得到了简化,两个主开关管中的一个能够工作在零电流开通和零电流关断状态,同步整流电路克服了死区和轻载环路电流的影响,电路的整体性能得到了提高。通过Saber软件对电路进行了仿真,并实验制作了一台15V/300W的样机,实验证明样机工作稳定,保护功能完备。

As one kind of the modern electric power converters, two-transistor forward converter has many attractive characteristics, such as low switching voltage stress and high reliability. The paper made analysis of the process of the improved circuit and the specific problems encountered in the applications, and gave the solutions of the prob- lems. Compared with the traditional circuit, the control circuit of the improved converter has been modified and simplified, namely,one of the two main switches is working at ZCS state, synchronous rectifier circuit can overcome the effects of the dead zone and light load loop current, and the circuit＇ s overall performance has been enhanced. Based on the simulation results, a 15V/300W power supply was developed during the experiment. The experiment proved that the power supply is stable and reliable.