Dear,
PFC stage used UCC28051, and the dual winding inductor determine the converter's frequnecy. Based on UCC38050 100W EVM, the inductor's value is 1mH that means the switching frequecy is about 25kHz. Based on UCC28600 120W EVM, the inductor's value is 232uH that means the switching frequency is about 107kHz.
Does that mean if I want use smaller transformer, I can let the switching frequency become higher. But how about the ripple current, that would also increase with switching frequency? Does it also effect power efficiency?
By the way is there any relationship between switching frequency and MOSFET in PFC stage?
Thanks