LFC with Storage Battery considering SOC for 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 owing to large fluctuations in the power output. To alleviate such fluctuations, this paper proposes a method for suppressing the frequency deviation in wind power generation using storage battery systems that consider the state of charge (SOC) and response speed differences between generators and storage battery systems. The method adjusts a low-pass filter (LPF) time constant and storage battery output according to the present SOC and applies H-infinity control theory to the generator controller to achieve robust control considering the parameter fluctuations generated by state variations in the power system. Using this approach, we design a load frequency control system that controls the internal variation caused by power system dynamics and the external variation caused by wind power generators. To verify the validity of the proposed method, we perform load frequency control (LFC) simulations and compare the frequency deviations between the proposed and the conventional methods.