Other Parts Discussed in Thread: UCC28950, UCC28180,
Hi Robert,
I have designed AC-DC charger by taking PMP8740 as a reference. I have a PFC stage with UCC28180 and followed by a 1KW PSFB stage with UCC28950.
My PSFB Specification as follows
Vin=400V(From UCC28180 PFC)
Vout=20V to 60V
Iout= 17A
There is No Fan in My design due to some reason. I am getting around 96% efficiency for PSFB alone.
I have used IPP65R190CFD as my Full bridge MOSFET and 30uH as shim inductor.I am getting ZVS action more than 20% of my output Load. Now I have some questions
1. My Full bridge MOSFETs reads around 50 degree more than 20% output load(ZVS action) But it reads around 90 degree temperature with less than 20% Load(non ZVS region) at ambient.
Since I dont have Fan this temperature is not acceptable. Can you suggest some way to solve this issue?
2. I have a 1uF capacitor series to Shim inductor just to balance the volt second. But in your design it is not present. What is the risk in removing the capacitor?.
You have not faced any volt second balance issue without capacitor?
Waiting for your valuable comments
Regards
Aneesh