Fast Active Power Distribution Method for Wind Farms Considering Fatigue Loads of Wind Turbines

To suppress the fatigue loads of wind turbines caused by wind farms participating in the frequency regulation process, this paper proposes a fast active power distribution method based on the cooperation of wind turbines and the wind farm. Firstly, the fatigue load expression formulas in two degrees of freedom corresponding to the shaft and the tower of the wind turbine are deduced, and the relationship between the fatigue load and the active power output change of the wind turbine is established. Secondly, by taking the minimization of the total fatigue loads and the minimization of distribution of fatigue loads in the wind farm as the optimization objectives, and considering the constraint that the sum of the adjusted active power of each wind turbine is the same as the required active power for frequency regulation of the wind farm, the fatigue loads of the wind farm can be reduced while guaranteeing similar characteristics of frequency regulation. Moreover, by continuously calculating its own fatigue sensitivity coefficients at each wind turbine controller, the wind farm controller solves the optimal strategies online by using the commercial solver, to guarantee the real-time active power control during frequency regulation. Finally, a case system consisting of 20 doubly-fed induction generator based wind turbines with 5 MW capacity is performed, and the effectiveness of the proposed method is analyzed and verified. © 2024 Automation of Electric Power Systems Press. All rights reserved.