Abstract
| This paper aims to investigate the step-down dc-dc converters from circuit analysis viewpoint. These converters have a lot of utilizations, including different applications in power energy conversion domain, being mentioned also in electromagnetic compatibility studies.That is why the study and the analysis of such devices were and continue to be of a real interest for the scientific community. For this purpose this paper aims to bring a contribution in the domain, by offering equivalent schemes of different accuracies and alternative methods of analysis in time-varying regimes for step-down dc-dc converters used in electromagnetic compatibility investigations. Various time analysis methods are used here in order to analyze the step-down dc-dc converter circuit. Each method is well explained, starting from the basic equations of the circuit, continuing with the particularities of the approaches and finalizing with the presentation of the equations sets in the final form. For each method a program was created where the obtained equations were implemented. The most important results are presented in each case; they correspond both to the steady state and to the initial variable regime. The final part focuses on the differences between the results obtained using the real nonlinear characteristics of some elements and those resulted using their linearized model. The resulted waveforms are discussed comparatively not only using different methods of analysis and linear and nonlinear schemes of the converter, but also using results offered by commercial software specialized in electric and electronic circuit analysis. Finally the advantages and the disadvantages of each method are underlined and some conclusions are depicted. |
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