Coordinated Pitch Control for Offshore Wind Turbines Based on Event-triggered Load Feedback and T-S Fuzzy Logic Reasoning

This paper addresses the conflicting issues of limited load suppression in collective pitch control and increased actuator burden in individual pitch control for large-scale offshore wind turbines operating above the rated wind speed. We propose a coordinated pitch control strategy, which includes an event-triggered blade root load feedback mechanism to eliminate redundant sampling signals and minimize the interference of real-time fluctuations on pitch actuation. Additionally, a coordinated pitch mechanism based on T-S fuzzy logic is developed to dynamically adjust the relative weights of collective and individual pitch commands, adapting to varying wind speeds by reasoning in real time based on blade load and its dynamic changes. This coordinated mechanism accommodates the highly nonlinear relationship between system load and pitch angle variations at different wind speeds. The integration of the T-S fuzzy logic-based pitch coordination mechanism with the eventtriggered blade root load feedback mechanism enhances the balance between reducing pitch actuator workload and suppressing system load in offshore wind turbines. Simulation results, conducted on the IEA 10MW offshore wind turbine, demonstrate that the proposed strategy outperforms traditional collective and individual pitch control strategies by effectively balancing actuator workload reduction and load suppression.