开关电源高频功率平面变压器热设计研究

高功率密度要求和高频下涡流损耗(包括磁芯和线圈的涡流损耗)的急剧增大对高频功率平面变压器的热设计带来巨大挑战.通过分析平面变压器热传递特性,提出一种可分别计算线圈和磁芯温升的热模型及其建模方法.此外,根据铁氧体磁芯的损耗温度特性,还提出一种平面变压器温度设计准则.实验证明提出的热模型具有足够高的工程精度,而提出的温度设计准则可使变压器具有良好的热稳定性,从而改善了平面变压器热性能.

Thermal design considerations for high-frequency power planar transformer

Higher power density requirement and dramatically increasing eddy current loss (including winding and core loss) impose severe challenges on thermal design of high-frequency planar transformer. Through heat transferring analysis of the planar transformer, a novel thermal model considering temperature rise of winding and core independently is proposed. Then a new design guideline of core temperature by analyzing relation between core loss and temperature is also given. The thermal model and the design guideline are helpful to improve the planar transformer thermal design. Experiments verified the thermal model and design consideration.