Supplementary load frequency control with storage battery operation considering SOC under large-scale wind power penetration

Wind power is a major source of renewable energy, and is in great demand around the world. However, wind power is difficult to manage due to large fluctuations in power output. To alleviate such fluctuations, this paper proposes a method for suppressing frequency deviation in wind power generation using storage battery systems that considers state of charge (SOC) and response speed differences between generators and storage battery systems. The method adjusts storage battery output according to present SOC, and applies H_∞ control theory to the generator controller to achieve robust control considering parameter fluctuations generated by state variations in the power system. Using this approach, we design a load frequency control system that controls both internal variation caused by power system dynamics and external variation caused by wind power generators. To verify the validity of the proposed method, we perform LFC simulations and compare frequency deviations between the proposed and conventional methods.