I–V Data Operated High-Quality Photovoltaic Solution Through Per-Unit Single-Diode Model

The work presented here uses a novel photovoltaic (PV) parameter extraction method that uses the generalized per-unit single-diode model (PUSDM) of a PV module. In the first extraction stage, the PUSDM is approximated as an explicit nonlinear model (EXNLM). The EXNLM utilizes the experimental current-voltage (I-V) data of a PV module to estimate initial guesses. The second stage exploits the PUSDM with reduced parameters and extracts the three parameters using the nonlinear least-square-fit (NLLSF) technique. The third stage refines the five parameters using the original PUSDM. Here, again the NLLSF is employed using the solution obtained in the second stage as the initial guesses. The proposed method is tested on the experimental and synthetic I-V curves of several silicon PV cells and modules commonly available in the PV literature using MATLAB programming platform. The high-quality PV solution is obtained with the least computational cost ever published in the PV literature. The other salient features of the work are: 1) an ability to work without the PV module key operating points, 2) a self-computation of the initial guesses, and 3) an ability to work with the partial I-V data points. Most importantly, the MATLAB-script of the proposed method is made available for ready-use through e-mail.