Frequency control of power system with wind farm by output frequency band control of adjustable-speed pumped-storage generator

This paper proposes a new control system for Adjustable-speed pumped-storage generator (ASG) to decrease frequency fluctuations of power system with a large amount of wind farm introduced. In recent years, environmental problems are becoming serious and wind power generation has been attracting much attention and introduced throughout the world due to its low environmental impacts. However, wind power generation is an unstable power source with fluctuating output due to wind speed variations. Thus, when a large amount of wind power generation is connected to the power system, it can decrease power quality, e.g., frequency variations. There are some methods to suppress the frequency fluctuation in the power system, among which ASG can be an effective countermeasure. However, there has not been sufficient report on the frequency control by using ASG. This paper proposes a new control system for ASG to decrease frequency fluctuations of power system which is based on the filtering method. It is shown by simulation analyses that the proposed ASG can decrease the frequency fluctuations than the conventional Fixed-Speed Pumped-Storage Generator (FSG).