非互补准谐振控制的有源箝位反激变换器

Noncomplementary Quasi-resonant Control Active Clamped Flyback Converter

有源箝位反激拓扑因具有效率高、高频特性好、抗电磁干扰能力强等优点获得了广泛应用。此处提出了一种新颖的控制策略,采用非互补导通模式,以减小箝位管的导通损耗,实现主开关管的零电压开关(ZVS)。同时让变换器工作于临界连续模式,采用准谐振控制模式进一步实现箝位管的谷底开通,优化了变换器的效率。采用过零检测电路实现临界连续模式,并引入峰值电流内环提高变换器的动态响应速度。

With the advantages of high efficiency,high frequency characteristics and strong anti-electro-magnetic interference capability,active clamped flyback topology is widely used.A new control strategy is proposed,noncomplementary conduction mode is adopted to reduce the conduction loss of the clamping switch tube,zero-voltage switch(ZVS)of main switch is also achieved.The converter operates in critical continuous mode and the quasi-resonant control mode is used to realize the valley switching of the clamping switch tube and optimize the efficiency of the converter.The zero-crossing detection circuit is adopted to realize critical continuous mode and the internal loop of peak current is introduced to improve the dynamic response speed of the converter.