Analysis of grid-tied single phase multilevel inverters powered by photovoltaic panels under partial shading conditions

Abstract

The recent growing in small grid-tied photovoltaic systems for residential users, with public and private investments politics found in several countries, started a demand for a new generation high efficiency DC-AC inverters. These inverters should have good modularity, low size, weight and cost, with good energy quality at output and maximum power tracking of each solar panel. Multilevel inverters, in special the Cascaded H-Bridge, have advantages when there is present several panels acting as independent sources. Some works have discussed his integration with commercial grid, focusing control techniques that can operate even under partial shading conditions of solar panels. This work will propose an adaptation in one of these techniques to allow a lower logic communication network between inverters and the central controller, without loss of performance and considering the photovoltaic panel's characteristics through a Matlab/Simulink model. © 2012 IEEE.