Fatima BOUMRIT1, Dumitru POPESCU2, Abdelkarim MOUMEN3, Abdelkarim ZATNI3, Abdenbi EL YAMANI3
Abstract. This paper presents a Global Maximum Power Point Tracking (GMPPT) method based on polynomial interpolation for photovoltaic systems under partial shading conditions. In the case of non-uniform irradiance, the photovoltaic power characteristic is nonlinear and may have multiple local maximum power points, increasing the risk of convergence to a non-optimal operating point. To this end, the proposed strategy exploits a limited number of selected duty-cycle and power measurements to build a low-order polynomial approximation of the power behavior around the most promising operating region. Then a bounded numerical optimization step is performed to estimate the duty cycle corresponding to the maximum interpolated power. A best power retention mechanism preserves the operating point corresponding to the highest extracted power. The efficiency of the method is tested by simulation in the case of a representative time-varying partial shading profile and then compared with P&O, INC, PSO and GWO algorithms. The obtained results show that the proposed method has a mean tracking efficiency of 99.11%, an energy-based efficiency of 99.15% and the lowest RMSE error of 1.0026 W. It presents the highest energy efficiency and the lowest mean tracking error in comparison with the other methods, confirming its capability to work close to the GMPP and to reduce unnecessary oscillations after convergence. The results indicate that polynomial interpolation can be used as a simple and effective numerical tool to improve MPPT performance in PV systems under partial shading conditions.
Keywords: Photovoltaic systems; Global maximum power point tracking; Partial shading conditions; Polynomial interpolation; Numerical optimization; Duty-cycle optimization.
DOI 10.56082/annalsarsciinfo.2026.1.58
1 Ph.D. student, University IBN ZOHR, faculty of sciences AGADIR, fatima.boumrit.61@edu.uiz.ac.ma
2 University Professor, Ph.D., POLITEHNICA Bucharest, Academy of Romanian Scientists, Popescu_upb@yahoo.com
3 University Professor, University IBN ZOHR, faculty of sciences AGADIR, a.moumen@uiz.ac.ma, a.zatni@uiz.ac.ma, a.elyamani@uiz.ac.ma
PUBLISHED in Annals of the Academy of Romanian Scientists Series on Science and Technology of Information, Volume 19, No1