Effect of Weather Conditions on Harmonic Performance of PV Inverters

The effect of weather conditions on the generation of harmonics in PV systems is investigated. A PV model, including the inverting stage, is considered. The output of the equivalent PV model is fed to the load via an inverter and transformer. The analysis is conducted by using a dataset of weather conditions in a North American city. Two converter techniques, which form the basis for the majority of converters, are used to validate the proposed approach: a square-wave inverter with 60 Hz switching, and pulse width modulation (PWM). Probability density functions and probability distribution models with best fit are determined as aids for improving the quality of the power generated for different range of converter values and the best is selected in this article. The long-term effects of weather conditions on harmonics produced by PV inverters are considered. The results show the variability in amplitude of each harmonic component, the boundaries of each harmonic component, and which harmonic magnitudes occur more frequently. The classic PV DC-AC conversion system has been modeled using MATLAB. The work is validated by using different ranges of dataset for two different converters and the results improved the importance of the proposed work. Also, the results agree with previous studies that have been carried with a different method which could be considered as another way of validation for the proposed work. Based on the generated harmonic variation cases, the appropriate parameter values for dynamic adaptive circuit switching of the filtering system and determining the capacity of the storage system could be determined.