基于UC3852的限频临界断续模式APFC

Frequency limited critical conduction mode APFC based on UC3852

通过对临界断续模式有源功率因数校正(APFC)工作原理的分析,指出了该种变换器由于开关频率可变,在高输入电压时将增加开关损耗以及EMI滤波难度。提出了利用控制芯片UC3852N限制开关频率以优化变换性能的方案。通过所研制的一台300W样机,证实了该方案的可行性。

Due to the variable switching frequency,the active power factor correction（APFC） operated in critical-conduction mode led to more switching loss and EMI problem at high input voltage,based on the principle analysis of the converter.A new method was presented to optimize the performance by limiting the switching frequency,based on the relevant function of UC3852N.A 300 W prototype was developed and the result is validated.