CUK CONVERTER WITH PI CONTROLLER

This model helps you in getting a basic idea of a CUK converter and PI application in converter.

This model which resembles a cuk converter which can be used for wide range of DC o/p's.As we know that cuk converter can be used for stepping up/down a given DC value.
The important thing that can be noticed from this model is that,it has a PI controller,which can be used for giving a DC constant(desired value of DC o/p),and the error signal is sent through a PI controller,which further helps in setting the particular Duty ratio,which simultaneously produces a desired DC output.
i've tried it in designing for value of 50/60 and 50/80...and it worked well....
but problem i faced was little overshoot..
i would be thankful for the suggestions in reducing it and getting a better design.