Estimation of state, actuator and sensor faults for T-S models

For nonlinear systems described by Takagi-Sugeno (T-S) model, a T-S observer is proposed to estimate both system state, sensor and actuator faults. The method uses the technique of descriptor systems by considering sensor and actuator faults as auxiliary state variables. This method has the advantage to estimate the state variables and the sensor and actuator faults simultaneously. The observer gains are then determined based on Linear Matrix Inequalities (LMI) technique. A numerical example is proposed to demonstrate the efficiency of the given design.