Microcontroller-Based Current Sensorless Photovoltaic MPP Tracker

A simple current sensorless perturb & observer (P&O) to extract maximum power in a photovoltaic (PV) power generation system is proposed in this paper. The existing techniques used for extracting the maximum power in a PV system, requires the current and voltage sensors. The use of current sensors (CS) for tracking maximum power point is completely avoided in the proposed work and the current information is estimated using an observer. The observer design varies, based on the present and past instant measurements of output and input voltages. This makes the system more simple, less costly, easy to implement and equally reliable. The effectiveness of the proposed method is studied with the help of a suitable simulation carried out in MATLAB environment and for experimental validation a microcontroller is used. The results obtained from the simulations and experimental studies showed that the proposed current sensorless method can track the maximum power point accurately.