Research Of Controller Reconfiguration For Reconfigurable Systems

A reconfigurable system in the control field is a sophisticated system with active control strategies adopted. It possesses advantages and edges in improving reliability and recovering performance:controlling a complex system well, also maintaining or degrading gracefully performance while ensuring the overall system stable in occurrence of faults. Therefore, control system reconfiguration turns out to be critical at present in making production efficient and safe, and plays a key role in such industries as manufacturing, transportation, metallurgy and chemistry, biomedical enterprises and so forth.Control system reconfiguration including reconfigurability analysis and controller reconfiguration is studied. First, it is stated generally, and a fault-hiding goal is introduced via traditional goals, with a reconfiguration module given. Linear reconfigurability is investigated and a reconfigurability analysis approach is presented.On the one hand, Chapter 3 studies controller reconfiguration for SISO system with failure-like faults. Several reconfiguration algorithms are summarized or proposed with their drawbacks pointed out. Thus controller reconfiguration synthesis based on stability analysis is presented. Simulation results show the validity of this method for a single fault.On the other hand, next two chapters carries out MIMO reconfiguration. To begin with, design control mixer via reconfigurability conditions, propose an improved method that guarantees closed-loop stability and constrains control energy because pseudo-inverse method (PIM) doesn't guarantee the stability. Simulation results show almost perfect effects if the system satisfies reconfigurability conditions. Otherwise, the reconfigured loop loses stability which is the drawback of static reconfiguration via PIM, whereas the improved methodology avoids that disadvantage. Then carry out MIMO dynamic reconfiguration using virtual reconligurer (VR). Utilize virtual actuator (VA) to stabilize the reconfigured system and design the extended VA using zeros placement. The thesis proves separation principle aiming at nominal and state deviation subsystems, and also duality of reconfigurer design for virtual actuator and virtual sensor. And employ VRs to deal with internal faults. Still simulate the failing example through PIM. Results show that reconfigured loop stability is guaranteed, set-point tracking goal based on the extended VA achieved, and the strong goal for disturbances also reached.