Single-phase voltage-doubler SEPIC rectifier with high power factor

Abstract

This paper introduces a single-phase PWM rectifier topology based on a discontinuous conduction mode (DCM) SEPIC converter. The structure integrates two SEPIC rectifiers, which work as half-wave rectifiers, one for each half-line cycle, in a unique converter, and the novel rectifier is designed as voltage-doubler SEPIC rectifier. A comparison with the classic SEPIC rectifier shows that the proposed converter might either provide reduced voltage stress on the semiconductors to the same output voltage level, or it might supply double the gain in the output voltage with the same voltage stress. This structure provides high power factor with no current control, as a classical DCM SEPIC rectifier. As a result, the proposed rectifier can be applied in order to improve the static gain of the DCM SEPIC rectifier and thus make it suitable for applications that demand high voltage level. The topology and theoretical analysis are presented in the paper and they were verified by experimental results, which were obtained in a prototype with the following specification: 1000W output power; 220V input voltage; 400V output voltage and 50 kHz switching frequency.