Hierarchical robust control for variable‐pitch wind turbine with actuator faults

Abstract

In this brief, we develop a fault tolerant control (FTC) using a hierarchical-robust methodology with guaranteed stability for a wind turbine (WT), which is subject to an exogenous input and an actuator fault. The high-level control is designed to robustly compensate for the nonlinearities, uncertainty, and disturbance in the system. The low-level control is designed to robustly automatically allocate control authority among redundant actuators mitigating an actuator fault. At the low-level, the robust control problem is transformed into an equivalent optimal control problem. Finally, the developed FTC is validated using a comprehensive simulation study on a 5 MW variable-pitch WT model given in the Fatigue, Aerodynamics, Structures, and Turbulence (FAST) simulator provided by the U.S. National Renewable Energy Laboratory (NREL). The results show that the developed FTC retains robust performance in the presence of wind disturbance and a time-varying actuator fault.

Fuzzy‐dependent switched fault‐tolerant tracking control for permanent magnet synchronous generator‐based wind energy conversion system

“…Then, we establish the switching technique to ensure the inequality ( 16) Based on the switching technique in (21), the fault-tolerant fuzzy controller can be designed as…”

“…Besides that the actuator faults are usually unavoidable in practical systems 21 because of electromagnetic interference, component ageing and so forth. The actuator faults may cause intense performance property deterioration of the generators or even generator instability, leading to severe destruction over all of the WECS, which will drastically impact the safety of the wind turbine and its stable power output 22 .…”