Apparent velocity of shadow edges caused by moving clouds

摘要

Even the largest photovoltaic (PV) power plants are widely affected by overpassing cloud shadows which have several harmful effects on the operation of PV systems. Irradiance transitions caused by edges of cloud shadows can be very steep and large and might lead to situations where the grid inverter is not able to follow the global maximum power point. Further, partial shading of PV systems causes mismatch losses and fast fluctuations of the power fed to the electric grid can cause power balance and quality problems.