Stability analysis of parallel DC-DC converters using a nonlinear approach

The authors develop analytic methodologies for stability analysis of a parallel DC-DC converter using its switching model, discrete model (based on nonlinear map) and averaged model. They use these methodologies to investigate the dynamics of an interleaved and a synchronized parallel DC-DC buck converter. Using the switching and discrete models they show the mechanism and boundaries of fast-scale and slow-scale instabilities. They show the difference in mechanism of fast-scale instability between the interleaved and a synchronized converter. The averaged model does not show this difference. It also differs considerably (from the other two models) in prediction of instability boundaries.