UCC25660: 1000W AC/DC system using a PFC UCC28180 + LLC UCC256601

The design specifications are Vout = 40V, with a typical output of 360W and a peak output of 1000W (1 second on, 3 seconds off, controlled by a secondary-side MCU).

We encountered an issue where the load power could not increase. To address this, we adjusted the RISNS value from 200 ohms to 110 ohms, which allowed the load to increase to 800W. However, with this RISNS value, when returning to a 360W load, the MOSFETs in the LLC circuit became unstable and overheated.

Since we only require a stable output of 360W, what other methods can be used to adjust the power limit for protection without changing the RISNS valu?(Possibility of entering a dead zone)

thanks & regard 

Noah