A Time-Based Global Maximum Power Point Tracking Technique for PV System

This paper presents a new global maximum power point tracking (GMPPT) technique for the photovoltaic (PV) array under uniform as well as non-uniform solar irradiance. The proposed method uses the I-V characteristic of the PV array to track the global peak. The proposed intelligent technique is based on the computation of settling time of the PV voltage to track the reference voltage given by the GMPPT algorithm. The computed settling time information is used to distinguish between the current source region and voltage source region of the PV array operating point. Thus, it is possible to identify the change in the region of operation, which is utilized to detect the presence of the local peak. After all local peaks are tracked, the GMPPT algorithm sets the reference operating voltage corresponding to the global peak. The given algorithm skips the settling of PV voltage to reference voltage when the operating voltage lies in the current source region during the global peak tracking. This helps in fast tracking of global peak. Furthermore, it does not require any complex mathematical operations like division which makes the proposed algorithm simple to implement. The performance of the proposed algorithm is further verified using both MATLAB/Simulink and experimental results.