I am working on a non-isolated boost converter, has 30khz switching frequency and uc3842b is used to implement peak current mode control. Three phase ac after rectification is applied as an input to a boost converter. When the input is in between 200vac-320vac, boost converter should give an output voltage of 475V and the maximum output current is 23A, When the applied voltage is in between 330V-475vac, the output voltage should be 750V and maximum output current is 23A. For input voltage 330V-475vac subharmonic oscillations taking place when duty is going beyond 50%. The circuit is working fine for input range 200vac-320vac(Because slope compensation is added for this range). My question is how to implement a slope compensation which is suitable for both supply ranges.