A Novel MPP Estimation Technique for DDM PV Array Under Different Solar Irradiance Conditions

This article derives a new explicit expression of current of a double-diode model (DDM) photovoltaic (PV) module from the implicit current-voltage (I-V) expression. Here, the exponential term of the I-V expression of a DDM PV module is represented by Taylor series. The validation is done on the implicit I-V expression with the derived quartic I-V explicit expression for PV modules of different rating under different environmental conditions (DEC). The estimation of maximum power point (MPP) is done using one dimensional Newton Raphson (NR) algorithm in the MPP region and proposed explicit expression. The proposed technique is also compared with the different existing MPP estimation techniques for DEC. The results show better accuracy of the proposed technique over the existing methods. Finally, a new mathematical model of totally cross tied (TCT) configuration of a PV array under partially shaded conditions is derived and the global MPP is estimated using an intelligent search algorithm i.e., genetic algorithm. Further, a 315 W PV module was considered for real time validation of the proposed technique under uniform irradiance condition. Also, the calculated global MPP of a DDM PV array of TCT configuration is validated with experimental results for different shading conditions.