新型冷却方式对APFC电路的适用性研究

Research on Applicability of New Cooling Mode to APFC Circuit

作为一种新型的冷却方式,以相变换热为特征的蒸发冷却技术在开关电源向小型化、绿色化的发展中表现出明显的技术优势。Boost有源功率因数校正(APFC)电路作为减少谐波污染、提高功率因数的有效方法,是开关电源常用的前级结构。针对采用全浸式蒸发冷却技术方案的开关电源中APFC电路出现母线电压升高的适用性问题,设计了APFC样机及其实验装置。通过实验和仿真,对比分析了该电路在空气中和蒸发冷却介质中的工作特性,确定引起蒸发冷却介质中运行电源母线电压升高的原因是高压侧采样电阻阻值升高。研究结论将为蒸发冷却技术在开关电源中的成功应用提供重要技术支撑。

Evaporative cooling technology, using the latent heat of cooling medium to take away heat, has obviously technical advantage in the cooling of switching power supply which develops towards miniaturization and green.Boost active power factor eorreet（APFC） circuit is commonly used in switching power supply to restrain harmonic current and improve power factor.The prototype of APFC and experimental device are designed to solve the applicability problem in cooling medium.The problem is that the bus voltage of APFC circuit in fully-immersion evaporative cooling switch- ing power supply would increase after working for a while.Practical working conditions of APFC circuit are studied in air and in cooling medium.The reason of increasing of bus voltage is that the sampling resistance on high voltage side in cooling medium increases.The study will provide essential technical support for the successful application of evapo- rative cooling technology on switching power supply.