基于次级调压的有源箝位正激变换器的研究

根据有源箝位正激变换器的工作原理和实现软开关的条件,研究了一种基于次级调压的有源箝位正激变换器。该拓扑电路初级处于固定占空比的开环工作状态,通过变压器次级的磁放大电路进行稳压。该技术解决了传统有源箝位变换器主开关管难以实现软开关的问题。此处详细分析了新型变换电路的工作过程,设计了一款25 W的电源样机。实验结果验证了该理论分析的正确性和拓扑电路的高效性,在整个负载范围内完全实现了主开关管和箝位开关管的软开关功能,且软开关实现的条件不依赖于变压器参数。

Research of Active-clamp Forward Converter Based on Secondary Voltage Regulator

According to the working principle of active-clamp circuit and the conditions to achieve soft-switching,active-clamp forward converter based on secondary voltage regulator is researched.With the fixed duty cycle,the primary circuit works in open-loop status.The output voltage is controlled through the magnetic amplifier of the transformer secondary side.This technology solves the shortcomings that main switch of the traditional active-clamp converter can’t be shut under zero voltage.It’s operation principles are analyzed and a 25 W power prototype is designed.The experi-mental results verify the correctness of the theoretical analysis and high effciency of the topology.