Study of DC/DC Topologies Associated to Multipulse Rectifiers with differential connections of transformers

Abstract

In the global context where more and more is discussed about sustainability, the theme power quality is becoming more popular, because power quality means less lost for consumers and electrical utility. This research plan is in accordance with this context, because it proposes a comparative study of some DC-DC converter topologies isolated or not, as a second stage for multipulse AC-DC converters. Efforts in this study will be analyzed: (a) digital control techniques with DSP device (Digital Signal Processor) and FPGA device (Field Programmable Gate-Array); (b) a new study with the SEPIC converter applied as a DC-DC stage in multipulse rectifiers; (c) the use of the DC stage in order to obtain the parallelism between the rectifier bridges of the AC-DC stage, to eliminate the IPTs (Inter Phase Transformers) and to reduce the weight and the volume for the structures; (d) to use the DC stage with the purpose to obtain isolation in high frequency and regulation in the DC output; (e) to use the DC-DC converter as a PFC (Power Factor Corrector) device, and further improve the current THD (Total Harmonic Distortion) and the Power Factor (PF) in the multipulse structures. The implicit goal is the scientific improvement of the candidate more specifically in switched converters and control techniques for mitigation of current harmonics in three-phase rectifiers.Rectifier topologies, based on Wye and Delta-differential connections, generalized and unified, was studied of the Direct PhD of the candidate with a scholarship by FAPESP entitled "Design methodology, classification and application of multipulse rectifiers with differential connections of transformers" will be used as the AC-DC stage in this Postdoctoral project. All the theoretical, the mathematical analysis and comparative results will be developed by digital simulation and mathematical specific programs, with numerical graphics results. It is wonder to obtain new results that contribute for the power electronics and application of multipulse rectifiers in the industry. Depending on the results, prototypes can be implemented to validate the proposed comparative process. The candidate has an appropriated profile for this solicitation, because worked for two years with scientific initiation scholarship and four years with PhD-Direct scholarship, both sponsored by FAPESP.