A new estimation method of irradiance on a partially shaded PV generator in grid-connected photovoltaic systems

• Published in: Renewable energy Vol. 33; no. 9; pp. 2048 - 2056
• Main Authors: Drif, M., Pérez, P.J., Aguilera, J., Aguilar, J.D.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.09.2008; Elsevier Science
• Subjects: Applied sciences; Energy; Equipments, installations and applications; Exact sciences and technology; Grid-connected PV system; Irradiance on tilted planes; Natural energy; Obstacles’ outline; Partial shading; Photovoltaic conversion; Shading factor; Solar energy; Solar radiation; Grid-connected PV system; Irradiance on tilted planes; Shading factor; Partial shading; Obstacles’ outline; Experimental test; Methodology; Obstacles' outline; Shading; Irradiance; Algorithm; Modeling; Simulation; Photovoltaic generator
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2007.12.010

A new method for estimating the irradiance on a partially shaded photovoltaic generator system is proposed. The basic principle of this method consists of two parts: firstly, an approximation of the obstacles’ outline or the local horizon by a set of linear functions. Here, a survey of the surroundings is based on the reading of the topographic coordinates of the only significant points of all the objects surrounding the photovoltaic generator. Secondly, the irradiance on the photovoltaic plane is estimated using an accurate model such as the Perez et al. model and assuming that the shading affects both the direct radiation and a part of the diffuse component (circumsolar component). The aim of this paper is to present the principles of the proposed method and the algorithm used for calculating the irradiance on shaded planes. In addition, the results of the comparison between the simulated and measured values of this method are presented.