Decentralized Power Curtailment Control using Real-time Pricing Strategy for PV Generation Plants with Storage and its Experimental Verification

In order to solve environmental issue and energy crisis, PV (photovoltaic) generation has experienced the most growth among the renewable energy sources in the last few years, and the interconnection capacity of PV generation may continue to increase. However, the more recently special problem in Japan, the capacity of qualified PV generation facilities exceeds the allowable interconnection capacity determined by each power grid company. This fact is recognized as a critical issue for reliable operations of power grids, and it will be enforced by law that the power grid company can announce the output power curtailment instruction signal to the PV generation plants. An output power curtailment essentially means wasting potential solar energy. Operating methodologies for the PV generation plant that can reduce the amount of wasted energy are needed to be developed. This paper considers the PV generation plant equipped with the battery storage and investigates decentralized control method of multiple PCSs (power conditioning systems) which are used to interconnect PV and storage system into the grid. The proposed decentralized management methodology consists of the real-time pricing strategy by the operator of the PV generation plant and distributed decision making by each PCS. We have developed an experimental environment which assumes the PV generation plant with battery storage having 2 MW total capacity. The effectiveness of the proposed methodology is evaluated through the real physical experiments.