Dynamic modeling of partial shading on photovoltaic arrays

Static partial shading on large photovoltaic arrays has already been modeled by many researchers over the last two decades. However, little research has been devoted to dynamic partial shading that is more realistic in practice. This project investigates an efficient MATLAB-based model that incorporates the dynamic characteristics of a photovoltaic (PV) module under a non-ideal moving shadow which has different degrees of shading. It is found that shadows with the same shape and transmittance configuration but different moving characteristics (such as initial point, speed and path) could transform the power-voltage curve of a PV array in different ways. This dynamic model can be used as a common platform to evaluate the effectiveness of the different MPP tracking algorithms and controllers under dynamically moving shadow conditions. Experimental results have been obtained to validate the model.