Predictive Functional Control for Linear Systems under Partial Actuator Faults and Application on an Injection Molding Batch Process

Actuator faults commonly exist in process control systems. Due to these faults, the controller may not achieve the required target, so the control performance may degrade. In this paper, the fault-tolerant control is designed through a predictive functional control framework to deal with partial actuator faults and unknown disturbances, which exist widely in process control systems. Based on a new state space formulation of the process models, an improved predictive functional control scheme is proposed, where satisfactory closed-loop control performance is achieved even with unknown disturbances and actuator faults. With the actuator faults, the system becomes a process with parameter uncertainties. Hence, a sufficient condition that guarantees closed-loop robust stability is presented. Simulations are given to illustrate the feasibility and effectiveness of the proposed scheme.