Nonlinear modeling and spectral analysis of Cuk converters

Being a fourth-order circuit, the Cuk converter needs systematic studies of its nonlinear dynamics. In this paper, the investigation of the nonlinear dynamics of Cuk converters is carried out by deriving their nonlinear models and performing their spectral analyses. Nonlinear dynamics, including the additional DC offset, significant subharmonic and higher harmonic spectral contamination as well as the effects of self-intermodulation and cross-intermodulation, due to large-signal perturbations of both the duty ratio and source voltage, are investigated.