Performance of Grid-Connected Photovoltaic Systems in Fixed and Sun-Tracking Configurations

This paper deals with the performance of grid- connected photovoltaic (PV) systems with parallel-connected converters. The focus of the paper is twofold. The first part concerns the assessment of the energy production and of the operational characteristics of multiple photovoltaic systems in Sun-tracking configurations, comparing their performance to the one of the corresponding fixed PV systems. The second part refers to assessing the harmonic characteristics of the integration of several converters in PV plants of various size. Different indicators are taken into account, including the individual and total harmonic distortion, the harmonic and interharmonic summation ratios at different harmonic orders, as well as the indicators formulated in the IEC Std. 61000-4-7 for group total harmonic distortion (THDG) and subgroup total harmonic distortion (THDS). Results from PV applications in Germany and Italy are shown and discussed.