Reference-Voltage-Line-Aided Power Incremental Algorithm for Photovoltaic GMPPT and Partial Shading Detection

Conventional global maximum power point tracking (GMPPT) algorithms show limited tracking speed and accuracy due to the unnecessary peak search considering the complexity of partial shading conditions (PSCs). This paper proposes a novel power incremental (PI) algorithm for photovoltaic GMPPT and partial shading detection with the aid of the reference voltage line (RVL), representing the voltage of possible peaks based on the derived analytical expressions. The proposed analytical solution can detect the occurrence of PSCs easily and never overlook GMPP. Furthermore, both the tracking speed and the efficiency can be improved due to the quick allocation of GMPP and the reduced search area. The proposed RVL-PI-GMPPT algorithm is straightforward without sophisticated searching iterations, which can reduce the computational burden. Combined with the low-cost feature without additional temperature or irradiance sensors, the proposed algorithm is very suitable for the practical engineering design. Both the simulations and experiments under various PSC patterns validated the effectiveness of the proposed algorithm. Conducted fair comparisons with other popular GMPPT methods, the average percentage change of tracking time by implementing the proposed RVL-PI-GMPPT algorithm under three-peaks PSC patterns is 108.9% compared with the PSO method and 209.9% compared with the 0.8Voc model method, respectively.