输出纹波最小化有源箝位正激磁集成变换器

传统的有源箝位变换器存在输出电流脉动较大的缺点。文中利用磁集成技术、将电感和变压器的交变磁通正向耦合，来减小有源箝位变换器的输出电流脉动。文中提出了磁集成有源箝位正激变换器，并对其工作原理进行详细分析。通过将零纹波点设定在0.5占空比处，使得变换器同时得到最小的输出电流纹波和最低的原边开关管的电压应力。文中给出了集成磁件的设计公式以及原边电流脉动和输出电流脉动的表达式。最后通过2台100W磁集成和传统式的有源箝位正激变换器的实验对比，验证了理论分析的正确性。实验表明，与传统的变换器相比，磁集成有源箝位变换器具有更高的变换效率和更小的输出纹波。

Active Forward Converter with Integrated-magnetics and minimum output ripple current

The large output ripple current impaired the performance of Active clamp forward (ACF) converter. By the ac flux positive coupling of the inductor and transformer, the output ripple current can be reduced. The improved ACF converter with integrated magnetics is proposed in this paper. The operation principle of the proposed converter is analyzed in detail. By setting D=0.5 as the zero ripple current point, the minimized output ripple current and minimized voltage stress of primary switches are achieved simultaneously. The design consideration for the integrated magnetics is discussed along with the effect on the ripple currents. Two 100W ACF prototype converters, with integrated magnetics and without, are built to verify the operation principle. Experimental results also proved that the proposed ACF converter has higher efficiency and lower output ripple current compared with conventional one.