High resolution shading modeling and performance simulation of sun-tracking photovoltaic systems

Abstract

A set of tools is being developed to increase the accuracy of energy conversion predictions for one and two axis vertical trackers. The work is centered on demonstrating accuracy improvements through finer resolution of simulation time steps, along with a more realistic calculation of mutual shading losses. The shading analysis tool is embedded in a CAD software environment and provides enhanced functionality to define arbitrary tracker geometry, module placement and string layout. Topographical aspects of the site are represented based on digital elevation model data and integrated as 3D surfaces for the tracker deployment. A dedicated energy conversion algorithm reproduces the complex behavior associated with partial shading of the PV array through solution of the system's electrical circuit. Effects of time step resolution and module layout are presented for an existing two-axis-tracking CPV plant.