Abstract :
Correct modelling of solar photovoltaic (PV) system yields is necessary to optimize system design, improve reliability of projected
outputs to ensure favourable project financing and to facilitate proper operations and maintenance. An improved methodology for fine
resolution modelling of PV systems is presented using module short-circuit current (Isc) at 5-min time-scales, and clearly identifies pertinent
error mechanisms that arise when working at this high resolution. This work used a modified version of the Sandia array performance
model, and introduces new factors to the calculation of Isc to account for identified error mechanisms, including instrumentation
alignment, spectral, and module power tolerance errors. A simple methodology was introduced and verified where specific module
parameters can be derived solely from properly filtered performance time series data. In particular, this paper focused on methodologies
for determining the predicted Isc for a variety of solar PV module types. These methods of regressive analysis significantly reduced the
error of the predicted model, and demonstrate the need for this form of modelling when evaluating long term PV array performance. This
methodology has applications for current systems operators, which will enable the extraction of useful module parameters from existing
data in addition to more precise continuous monitoring of existing systems, and can also be used to more accurately model and optimize
new systems.
2012 Elsevier Ltd. All rights reserved
