Strategy of Frequency Control Based on Variable Universe Fuzzy Logic in Interconnected Power System with Wind Power and Energy Storage.

The penetration of wind power in the power grid continually increases and the uncertainty of its output threatens the stability of system frequency. In order to improve the frequency fluctuation problem in the interconnected power system caused by the high penetration of wind power, this paper proposes a novel load frequency controller based on variable universe fuzzy logic and PI control. The variable universe fuzzy logic has been applied to improve traditional PI control method to meet control requirements of the nonlinear system with much uncertainty. A new universal variable universe contraction-expansion factor based on fuzzy inference with low designed difficulty has been presented to satisfy the different demands of input universe variation. A multi-area interconnected power system LFC model has been constructed containing the uncertainty of wind power output. In the simulation, the proposed variable universe fuzzy PI controller is compared with the fuzzy PI controller, the planar cloud PI controller, and the traditional PI controller. Simulation results show that the proposed controller has good dynamic and static performance under different disturbances, and has robustness when the deviation of system parameters exists.