Hybrid Wind Power System to Absorb Power Fluctuation by Battery Energy Storage System

As more and more wind turbines and farms are constructed in Japan, utility companies have introduced a grid code, which is effective in controlling the grid frequency. We designed a hybrid system by combining charge/discharge properties of lead-acid batteries with long life, and a power control of wind turbines to ensure the code. We also constructed a wind farm with this system in Shiura, Japan, which went into operation in January 2010. This system showed reduction in wind farm power fluctuation, and that battery capacity can be maintained for 17 years.