Search

This paper proposes an isolated three-phase rectifier power-factor correction using two single-phase buck preregulators in continuous conduction mode. The use of the Scott transformer renders a simple and robust rectifier to operate with unity power factor. With only two active switches, the rectifier is able to generate symmetrical currents in the line and a regulated voltage output without any necessary synchronous switches. The proposed control technique with sinusoidal pulse width modulation uses a feedforward of the output inductor current and only one voltage control regulates the output. Complete simulation results under closed-loop operation are given and a 12-kW prototype has been implemented in the laboratory, which demonstrated to operate successfully with excellent performance, and thus can feasibly be implemented in higher power applications. [ABSTRACT FROM AUTHOR]

A three-phase dc–dc converter based on the three-phase neutral point clamped (NPC) commutation cell is proposed, which is intended for use in applications where the energy from a medium dc bus voltage needs to be processed. In this paper, all six continuous conduction modes (CCMs) are described, presenting the main waveforms and equations. For the discontinuous conduction modes the main equations are also provided for a complete converter characterization. Experimental results for a 10 kW, 800 V input voltage, 200 V output voltage, 91% efficiency, 40 kHz laboratory prototype are also presented to verify the theoretical analysis carried out. [ABSTRACT FROM AUTHOR]

Presents information on a study which focused on a novel single-phase power-factor pulsewidth-modulated boost rectifier. Novel topology and principle of operation; Analysis of commutation; Conclusions.

Presents information on a study which analyzed a proposed high-power-factor three-phase alternating current (AC)-direct current (DC) converter composed of a line interphase transformer (LIT) and two three-phase rectifiers and pulsewidth modulation dc-dc boost converter. Description of the proposed circuit; Principle of operation; Data analysis; Results.