I am trying to implement a PI controller to regulate the output voltage of a Buck Boost Converter. The link shows my circuit layout. The way i implemented the PI controller with PWM works on a buck converter.
However, when i switch it to a buck boost converter, it doesnt work. From what i see, there is no output being feedback to the sum-er to be added to the Vref of 20V.
Appreciate any help on this, as i have been stuck at this problem for days.