一种隔离型有源箝位交错并联Boost软开关变换器

An Isolated Active-clamp Interleaved Boost Converter

采用原边并联/副边并联的交错结构,提出了一种新型的隔离型有源箝位交错并联Boost软开关变换器。耦合电感的漏感限制了输出二极管关断电流的下降速率,抑止了输出二极管的反向恢复,大大减小了反向恢复电流引起的损耗。由有源开关和箝位电容组成的箝位电路吸收并无损的转移了漏感能量,消除了主开关管上的电压尖峰,而两相交错并联电路只需要一组箝位电路,大大简化了电路结构。在整个开关周期内,主开关管和辅助开关管都是零电压软开关动作,大大减小了开关损耗。最后,设计了一台40V输入、380V输出的1kW试验样机。试验结果表明,所有的功率器件均为软开关工作。

A primary-parallel-secondary-parallel （PPSP） interleaved structure is employed to handle the large input current and to reduce the current ripple. Only a set of active-clamp circuit composed of a switch and a small capacitor is necessary to recycle the leakage energy of the coupledlnductors and to suppress the turn-off voltage spikes. Both the main switches and the active-clamp switch are ZVT soft switching performance during the whole switching transition. Meanwhile, the output diode reverse-recovery problem is alleviated dramatically by the leakage inductance of the coupled inductors. So the reverse-recovery losses are reduced and the EMI noise is suppressed. A prototype with 40 V to 380 V rated at 1 kW has been built to verify the effectiveness of the proposed circuit.