EXTRACTION OF MAXIMUM POWER FROM THE PV SYSTEM UNDER DIFFERENT CONDITIONS CONNECTED WITH DIFFERENT DC -DC CONVERTERS

摘要

In PV systems, dozens of PV cells are connected in series to form high-voltage strings, and multiple strings are connected in parallel to build modules with desired output ratings. A relatively large current mismatch between the component cells of a module is common, due to non-uniform cell optical characteristics, misalignment in the concentrators, electrical and thermal parameter variations, non-uniform aging, as well as partial shading. Due to this there is a large drop in PV system output power. In this paper, Delta-conversion concept is introduced that aims at averaging out differences in output power between groups of PV cells within modules and between modules inside the PV system and an attempt is made to compare with other existing different converters. This paper describes implementation details of the delta-conversion concept and compares with other sigma converters.