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UCC28951-Q1: I can't increase the output voltage to 43.8V in Pspice

Part Number: UCC28951-Q1

Hello, I need to make an 2kW Phase Shift Full Bridge converter. At the moment I am using the reference model SLUSA16D EVM: SLUU421A. 

I am trying to simulate this model, I also used the excelspreadsheet to adjust the parameters to get my specifications.

Specifications:

Vin : 360 VDC - 410VDC

Vout: 43.8VDC

Power: 2kW Iout: 45.6A 

I also the resistors on the pins for EA- and EA+ from the UCC28951-Q1 to get the 43.8VDC. I changed the Turn ratio of the transformer from 21 to 5.38.

I also changed the synchronous rectification MOSFETS to MOSFETS with 90A IDC and 200 Vds.

As you can see here, the output voltage won't go any higher. Also the input current in L3 won't increase it just decrease. But in the reference model the input current increases with the output voltage and it stabilize. 

My simulation 43.8Vout simulation:

12Vout Reference  simulation:


Hope someone sees this, thanks for reading. Kind regards,

Xiao Feng Lin (Jason Lin)