Generalized state-space averaging modeling to fourth-order power converters operating in DCM

This paper presents a novel methodology for correcting the state-space averaging (SSA) modeling for DC-DC power converters represented for fourth-order systems operating in discontinuous conduction mode (DCM). SSA modeling has been widely employed for converters operating in continuous conduction mode (CCM), obtaining a good similarity between the switched converter and the mathematical model. In contrast, when the converters work in DCM, significant deviations between the average and RMS values imply errors in the SSA model. Hence, the proposed generalized SSA modeling methodology provides an accurate model to aid the controllers and system design. Consequently, the proposed technique can be applied to distinct fourth-order power converters such as Zeta, & Cacute;uk, and SEPIC in several applications. Additionally, SSA corrections can be associated with different techniques for obtaining the small-signals representation. Simulation and experimental results and mathematical analyses that prove the feasibility and functionality of the proposal are addressed. Initially, the main SSA models are obtained for fourth-order converters. The proposed method corrects the models by mathematical manipulations. Several modeling techniques can be applied. The model can be evaluated from the simulation and experimental results. In addition, proper control can be defined and tuned. image