Fuzzy Logic Controller Based Perturb and Observe Algorithm for Photovoltaic Water Pump System

Photovoltaic (PV) panels are devices that convert sun light into electrical energy and are considered to be one of the major ways of producing clean and inexhaustible renewable energy. However, these devices do not always naturally operate at maximum efficiency due to the nonlinearity of their output current-voltage characteristic which is affected by the panel temperature and irradiance. Hence, the addition of a high performance maximum-powerpoint tracking, MPPT, power converter interface is the key to keeping the PV system operating at the optimum power point which then gives maximum efficiency. In this paper, new adaptive P&O method with variable step size is investigated by using fuzzy logic control. This control technique automatically adjusts the step size to track MPP. The proposed method can largely improve the MPPT response speed and accuracy at steady state simultaneously with less steady-state oscillation. The obtained results demonstrate the efficiency of the proposed MPPT algorithm in terms of speed in MPP tracking and accuracy.