Development and analysis of a power electronic interface for single-phase AC grid supplying DC loads

Abstract

ABSTRACT A power electronic configuration consisting of a diode bridge rectifier (DBR) cascaded with a super-lift converter is proposed for supplying DC loads from the AC grid with reduced total harmonic distortion (THD) at the grid side. The super-lift converter used in this work is a DC–DC converter named Negative Luo converter (NLC). This NLC has high voltage gain and reduced ripples at the output. As the displacement factor of the DBR is almost unity, combining this with the NLC results in the reduction of harmonics in the system. Hence, a harmonic-free, lower peak current is drawn from the AC mains using the proposed converter topology. Besides, the proposed closed-loop controller also helps in maintaining a constant DC voltage at the load terminals. A comparative analysis of the NLC converter topology is carried out with a conventional voltage lift converter, namely the CUK. The entire proposed system is simulated using MATLAB, and the simulation performance is studied. The experimental setup of the proposed converter is developed in the laboratory, and the results are presented. The closeness of the simulation and experimental results validate the proposed converter configuration.