A model based 2-DOF fault tolerant control strategy

In this paper, a novel concept of model based fault tolerance control (FTC) is presented. The FTC is achieved by 2-DOF control strategy: feedback control and feed forward control. Robustness issues are handled by the optimal feedback control and the time varying fault behavior by feed forward path. Firstly, a fault diagnosis scheme is presented for detecting and estimating the fault behavior from the observer based residual generator. The estimated behavior of the fault is used by the feed-forward control algorithm to make appropriate changes in the manipulated variable which keeps the controlled variable near to its set value. The effectiveness of the proposed scheme is analyzed using behavioral theoretic approach.