Other Parts Discussed in Thread: UCC28070
Hi,
I have the following doubt;
1. While designing the PFC (Boost, CCM), the losses in the output bulk capacitor is Irms2*ESR.
Let us say, i am designing a 1200W PFC over the universal input with 400V as my DC bus and 100% efficiency,
my capacitor losses are coming out to be 9.91 W.
Even if I use MLCC on the output side, only the high frequency ripple is what is bypassed and low frequency ripple goes through only the bulk capacitor.
I have seen some reference designs on boost PFC. There the loss percentage of capacitors is also mentioned in the overall loss split-up.
How is this issue addressed in practical designs without extra forced cooling? The thermal resistance of the capacitor is also so high that it is not that easy to transfer heat!
Thanks,
Siri