Robust Control of Systems Subject to Actuator Saturation and Disturbance

In this paper the conditions to satisfy invariance of closed loop system and L₂ performance of disturbance attenuation are presented for systems subject to actuator saturation and bounded disturbance. A robust state feedback controller is derived based on linear matrix inequality (LMI). In addition, the proposed method is applied to speed controlled plant of rolling mill. It is shown from the numerical simulations that the designed robust state feedback controlled system has better performance of disturbance attenuation and robust stability and can track time-varying composite signal effectively when the saturation degree is chosen appropriately.