A Design Method for a Two-Degrees-of-Freedom GPC Based on a State Space Approach

摘要

This paper considers a new GPC controller designed from the viewpoint of the two-degrees-of-freedom* compensator scheme based on a state space approach. In the proposed method, the gain of the integrator can be designed independently of thenominal transient response to the reference signal. In addition, the integrator comes into play only in the presence of disturbances and/or model-plant mismatch. Hence, the proposed GPC control law provides overall robustness in the closed loop systembecause the integrator brings about an undesirable phase lag and often may cause undesirable performance degradation in the controlled processes. The effectiveness of the proposed two-degrees-of-freedom GPC is demonstrated by simulation experiments andexperimented evaluation on a computer-interfaced pilot plant.