Comparative study of M-FIS FLC and modified P&O MPPT techniques under partial shading and variable load conditions

Most of the conventional tracking techniques fail to track maximum power point under partially shaded conditions as the photovoltaic (PV) array characteristic curves exhibit multiple local maxima. This paper put forward an adaptive maximum power point tracking technique (MPPT) for PV array which can perform even in non-uniform irradiance conditions. The proposed method targets on extracting the power of non-shaded PV cells during partial shading condition with the help of forward biased bypass diode across the shaded PV cells. The proposed technique implements Mamdani fuzzy inference system based fuzzy logic to control which is further equipped with DC-DC boost converters. The proposed technique enables the PV array to operate efficiently at variable load and non-uniform irradiance condition. The effectiveness of the proposed MPPT technique is investigated for various partial shaded patterns and variable load conditions and the results are compared with the modified perturb & observe MPPT technique.