基于UPC1909的有源箝位软开关变换器

在常规的硬开关电路中，由于变压器漏感及寄生电容的影响，常常在开关转换瞬间会产生很高的电压尖峰。本文采用有源箝位反激式变换器电路，实现了零电压零电流(ZVZCS)软开关变换，使电压尖峰得到了抑制。该电路成功地应用了UPCI909控制芯片，简化了传统的驱动电路。实验结果表明，主开关管两端电压被箝位在一定数值，实现了零电压零电流开关，效率达到90％。

An Active Clamp Soft Switching Converter Based on UPC 1909

In common hard switching circuit, high voltage spike usually could be produced during switch transition process because of the effect of transformer leakage inductance and parasitic capacitor. An active-clamp flyback converter circuit is presented to realize Zero-Voltage and Zero-Current Switching(ZVZCS) transition and at the same time suppress the voltage spike. By using control chip UPC 1909, the traditional drive circuit can be simplified. The test results show that the voltage of main switch can be clamped to a certain value, the Zero-Voltage and Zero-Current Switching and high efficiency can be achieved easily.