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The need for solid-state ac-dc converters to improve power quality in terms of power-factor correction (PFC), reduced total harmonic distortion at input ac mains, and precisely regulated dc output have motivated the proposal of several topologies based on classical converters such as buck, boost, and buck-boost. Additionally, novel control techniques(More)
—This paper presents the conception and analysis of a switch-mode power supply (SMPS) with desirable characteristics of high-frequency isolation, high input power factor, low harmonic distortion, and high efficiency. Nearly unity input power factor can be obtained by using an interleaved boost converter associated with a nondissipative snubber, as high(More)
This paper presents the analysis, design, and simulation results for a ZVS bidirectional isolated three-phase DC-DC converter with dual phase-shift and variable duty cycle. The topology uses three single H-bridges in the primary side and a three-phase inverter in the secondary side. The isolation is ensured by using three single-phase transformers connected(More)
High voltage step-up is necessary in several applications, especially considering that dc-ac converters must be supplied by high dc voltages. The conventional boost converter is the most popular topology for this purpose, although the conversion efficiency is limited at high duty cycle values. In order to overcome such limitation and improve the conversion(More)
—The study of a topology resulting from the combination of two forward structures attached to a single transformer core is presented in this paper, as a dual active bridge converter is obtained. In order to reduce the switching losses and the electromagnetic interference, a soft commutation cell, which provides zero-voltage commutation of the main switches(More)
This work presents a comparative study of single-phase boost-based ac-dc converters applied to power factor correction. Three structures are chosen for this purpose and analyzed in detail e.g. the classical boost converter, the bridgeless boost converter, and the boost converter based on the three-state switching cell (3SSC) operating in continuous(More)