Interval estimation of actuator fault by interval analysis

This study proposes an interval estimation method of actuator fault for linear discrete-time system. An augmented descriptor system, which is equivalent to the original system, is formulated by letting the actuator fault term be an auxiliary state. Then, an $H-{\infty }$H∞ fault estimation observer is constructed to attenuate the effect of unknown but bounded disturbances and measurement noise. By using interval analysis technique, the interval estimation of actuator fault can be obtained. Finally, a DC servo-motor example is given to show the effectiveness and superiority of the proposed method.