Implementation of a Sub-Hourly Clipping Correction in PVsyst

Simulating PV systems with a large DC:AC ratio in hourly steps will underestimate the clipping losses, when sub-hourly irradiance fluctuations are close to the clipping level. In a previous work [1], we developed a model to effectively correct this underestimation. The model is based on the once-only extraction of fluctuation information from horizontal plane sub-hourly weather data, which is stored together with the aggregated hourly weather data. This additional hourly data allows one to compute the sub-hourly clipping correction for any kind of PV system that is simulated with this hourly weather data. In the present work, we describe the implementation of this model in the PVsyst software and study its impact on the simulation results in different situations.