Estimation of photovoltaic power generation output based on solar irradiation and frequency classification

In this paper, a method to estimate total power output of clustered photovoltaic power generation system (PV systems) is proposed. The proposed method make use of the realtime communication between pyranometer, current/voltage sensors, and control center to estimate power output of PV systems based on solar irradiation and power flow in the feeder, where PV systems are connected. The proposed method is divided into low-frequency and high-frequency component estimations. The low-frequency component is estimated based on the correlation between solar irradiation and energy generated from PV systems. On the other hand, the high-frequency component is estimated based on the frequency classification of power flow. Performance of the proposed method is confirmed based on real data from Demonstrative Project on Grid-Interconnection of Clustered Photovoltaic Power Generation Systems supported by New Energy and Industrial Technology Development Organization, Japan. Results show that the error of estimation is approximately 3-4% of installed capacity of PV system.