Fault-tolerant Control of Floating Offshore Wind Turbine’s Pitch System Under Actuation Faults

The wind power industry has boomed in the decades and offshore wind energy has been growing rapidly in the recent year. However, the significant O&M cost became one of the factors hindering the development of floating WT. From the perspective of entrepreneurs, there exists a tradeoff between keeping the O&M costs at a low level and keeping the WT in normal operation. The pitch system is a key subsystem of the WT and the pitch system failures increase the O&M costs dramatically. Driven by this, this paper investigated a FTC strategy to maintain nominal pitching performance by tracking the demanded pitch angle in the presence of actuator faults. The proposed method effectively handling the unknown actuator faults, modeling uncertainties, and external disturbance with no need for the fault detection and diagnosis process. The tracking error of the pitch angle is ensured to converge to an adjustable residual set within prescribed finite time at a user pre-assignable decay rate. Simulation results show that the proposed scheme yielded a favorable fault-tolerant tracking performance.