An Improved Indirect Maximum Power Point Tracking Method for Standalone Photovoltaic Systems

This paper presents an improved indirect maximum power point tracking (MPPT) method for a standalone photovoltaic (PV) generation system. The proposed method is based on curve fitting for finding the best fit for the P-V characteristic curve by representing it in terms of a polynomial function of the fourth degree. The predicted P-V curve strongly depends on the cell temperature and therefore the ambient temperature and solar radiation are used to track the maximum power point (MPP) of the PV module. Experimental results are given to verify the validity and performance of the MPPT algorithm which is embedded in a prototype MPPT controller. The experimental results show that the proposed MPPT controller which is tested on a standalone PV system successfully tracked the MPP by giving an average tracking efficiency of 89.2%.