Prediction of the Overall Effect of Cloud Cover on Power Quality of PV Solar Power Plants

The shading effect due to cloud cover on PV solar power plants is a huge challenge in the maintenance of power quality. It can cause a power ramp down due to the movement of clouds in blue skies while the movement of clouds in a grey sky causes a significant loss of power in solar power plants. This paper presents a systematic approach for segmenting, tracking, and predicting the path of the clouds over the sky. It also develops a short-term solar energy forecasting model to predict the power output of the solar plant. The forecasting model uses real-time measurements to extract the average solar irradiance value and the power output of the plant for short-term prediction. The testing was carried out in a PV solar plant over one year. Within the implemented setup, the predicted power output cloud level and real-time video of cloud detection together with predicted power output are displayed on the Graphical User Interface. Accurate real-time detection, segmentation, and movement of distinct levels of cloud luminosity are presented. Extensive field trials showed promising results of meeting the stability requirements demanded by the regulating authority, from the large-scale grid tied PV solar plant operators. Hence authors expect the outcome will contribute towards migration into an integrated grid 4.0.