State space averaging model of a dual stage converter in discontinuous conduction mode

This paper presents an approach towards modeling a dual switch converter operating in discontinuous conduction mode (DCM) using state space averaging. To verify the accuracy of the developed model, a cascaded buck boost converter is used. However, the developed modeling approach is generic for various dual stage converters. The developed state space averaged model allows the application of modern control techniques (e.g. state feedback and linear quadratic regulator control techniques) on dual stage converters operating in DCM. The duty ratio constraint and the correction terms used in this model are driven to accurately predict the high frequency behavior of the system. Consequently, a full order averaged model is developed and verified through the small signal responses to the input variations at different operating conditions.