Optimal Design of Transformer less Grid-Connected PV Inverters

Abstract

With the reduction of available fossil fuels, the research in the area of renewable energy systems has been exponentially innovated in order to provide effective solar power solutions. The main objective of this thesis is increasing the efficiency and reduce the Levelized Cost Of the Electricity (LCOE) of the output power for the PV inverters. This goal has been achieved by determining the optimum inclination angle of photovoice panels during summer and winter and defined the optimum values of LCL output filter of PV inverter. Furthermore, provided a comparison between the three types of PV panels. A case study was developed based on a real PV system which installed in Heliopolis University for Sustainable Development (HUSD). This system consists of three different modules (Mono-crystalline, Poly-crystalline, and Thin film), where each type is connected to an inverter with output power 1.5 KW. The adjusting results revealed that the suitable inclination angle for both summer and winter seasons is 30o for the three investigated PV modules. Additionally, the Thin Film PV panels found to be the most efficient PV type among the installed modules. Grid-connected inverters were utilized with LCL output filter to attenuate the switching harmonics generated from Pulse- width modulations (PWM).