Reduced Losses in PV Converters by Modulation of the DC Link Voltage

Abstract

The efficiency of a PV system has improved by the fact that the researchers have used different techniques to enhance their efficiency. This paper aims to present how the PV converter losses can be reduced by employing a polypropylene capacitor in the DC link and to modulate that DC voltage. A problem of controllability and stability arises. Two current control methods, constant off time and a PWM type with second order high pass filter DC-link feedback are presented. Polypropylene capacitors in the PV converters do have lower losses and a lower cost. The PV converter simulation and lab experiment is based on a three-phase bridge APTGF50X60T3G, used to combine a step-up/step down and H-bridge in one package.