Power Estimation of Photovoltaic System using 4 and 5-parameter Solar Cell Models under Real Outdoor Conditions

Solar photovoltaic systems are widely used to generate electricity from solar energy but the reliability and efficiency of PV systems are always of serious concern due to intermittent nature of solar radiation. The performance of the photovoltaic system depends upon various factors like type of solar PV technology used, irradiance, module temperature, wind speed, ambient temperature and other outdoor environmental conditions. The main objective of the study is to identify a suitable solar cell model for power prediction of a PV system for a location of interest and validate the results experimentally. A single diode model with 4 and 5-parameters is used for modeling of PV arrays. A hybrid approach of analytical and numerical methods has been utilized to identify the accurate parameters of solar cell model. The instantaneous output power is predicted by considering the effects of irradiance and module temperature on the power generation. The predicted power by both the 4 and 5-parameters models are compared and validated using an experimental PV system. The average percentage difference error between measured and predicted output power values for the 5-parameter model is 4.95% and 4-parameter model is 5.16%. The output power predicted using 5-parameter model is found to be much closer to measured values.