Fault tolerant control of wind turbine using Laguerre and Kautz MPC for compensation

Abstract

In this paper fault tolerant control is performed to counterbalance actuators faults in wind turbines using model predictive control (MPC). Laguerre and Kautz MPC parameterizations are used in order to improve the numerical conditioning of the MPC optimization problem. The formulation of Laguerre and Kautz MPC for fault compensation is developed. Faults in the actuators of the blade pitch angle are considered. A step of fault detection and estimation is first done. As pitch fault is due to a change in the dynamics, it is estimated using a Kalman-like observer. Then, MPC compensator is employed to calculate the input that minimizes the difference between the defected sensor (for which the model is estimated using the observer) and the nominal situation (without fault). The implementation of the combined estimation and Laguerre/Kautz MPC compensator are found to offer a good online estimation and compensation of the fault under realistic fault scenarios in the wind turbine benchmark.