Journal of Energy and Power Engineering 6 (2012) 1965-1975 A Matlab/Simulink-Based Photovoltaic Array Model Employing SimPowerSystems Toolbox Samer Said 1 , Ahmed Massoud 1 , Mohieddine Benammar 1 and Shehab Ahmed 2 1. Department of Electrical Engineering, Qatar University, Doha P.O. Box 2713, Qatar 2. Department of Electrical and Computer Engineering, Texas A&M University at Qatar, Doha P.O. Box 23874, Qatar Received: February 27, 2012 / Accepted: April 18, 2012 / Published: December 31, 2012. Abstract: The modeling of PV (photovoltaic) systems is very crucial for embedded power system applications and maximum power point tracking. This paper presents a PV array model using Matlab/Simulink with the assistance of SimPowerSystem toolbox. The PV cell is considered as the main building block for simulating and monitoring the PV array performance. The PV model has been developed and used as Simulink subsystems where the effect of solar insolation and PV array temperature on commercial PV modules have been studied throughout the simulated I-V and P-V output characteristics. The proposed model facilitates simulating the dynamic performance of PV-based power systems. The effect of different partial shading patterns of PV arrays under different configurations has been studied. Key words: Modeling, PV, solar energy, Matlab, shading. 1. Introduction Developing alternative energy resources with high efficiency and low emission has become of great importance with increasing concerns about fossil fuel deficit, high oil prices, global warming, and damage to environment and ecosystem. Abundance and sustainability of solar radiant energy are important factors that characterize the energy through the PV (photovoltaic) effect among the renewable energy resources. Regardless of the intermittency of sunlight, solar energy is widely available and completely free of cost [1-4]. Recently, PV array systems have been used in several electric power applications. Despite of the high initial cost and low efficiency, PV system has small operation and maintenance costs as it is a stationary source of energy fabricated from semiconductor material. Compared with the oil prices, the solar energy is a feasible energy supply with great Corresponding author: Ahmed Massoud, associate professor, research fields: power electronics, energy conversion, renewable energy, and power quality. E-mail: ahmed.massoud@qu.edu.qa. long-term benefits. PV cell is considered the fundamental power conversion unit of a PV-based power system [1]. Solar insolation, temperature, and output voltage of PV are the essential factors that affect the output characteristics of a PV cell. Since the PV has a nonlinear current-voltage (I-V) characteristic, it is vital to model the PV unit for MPPT (maximum power point tracking) in PV-based power systems [1-5]. PV systems are considered an important type of distributed power generation systems. Also, it could be used as a standalone system. However, PV array operation in this type of power systems suffers from the effect of complete or partial shading, which is usually caused by clouds, trees, and near buildings. Under partially shaded conditions, the I-V characteristic of the PV array become complex with multiple peaks. These different peaks are generated due to the non-uniform insolation levels that are received on a partially-shaded PV array surface. The PV array efficiency is decreased due to these non-uniform characteristics. As a consequence, the conventional MPPT algorithm fails D DAVID PUBLISHING