Dynamic Analysis of a Boost Converter With Ripple Cancellation Network by Model-Reduction Techniques

The boost topology with ripple cancellation network allows input and output current ripples attenuation, which means the suppression of the input filter and a high reduction of the output filter. However, to achieve the ripple cancellation, the complexity and the number of components of the converter need to be increased as compared with the conventional boost. A detailed analysis is developed to specify the advantages and disadvantages of this topology. This paper presents the averaged model that derives the complex transfer function of the topology. The theoretical transfer function is obtained. Due to the complexity of the seventh-order transfer function that is obtained, a simplified second-order transfer function is calculated to simplify control design calculations. A comparison between the analyzed topology and a conventional boost in terms of weight and losses is carried out. To estimate the current ripple calculation, it is proposed to use the ripple theorem, which allows an estimation of the efficiency of the cancellation network using the averaged model. A prototype to validate ripple cancellation and the dynamic analysis is developed. Measured waveforms and Bode plots are enclosed. Current ripple cancellation at the input and output in both conduction modes of the converter is also validated.