Decentralized adaptive internal model control for multi-input multi-output systems

A continuous-time decentralized adaptive internal model controller is proposed for the control of an N×N MIMO system with unknown parameters. By treating the MIMO system as an interconnection of N linear SISO subsystems with “weak” interactions, robust adaptive internal model controllers are designed for each isolated subsystem. Each local adaptive control law utilizes a normalizing signal which is generated using the local output and the inputs of all the subsystems. This necessitates the exchange of input signals between the different subsystems so that the scheme is no longer totally decentralized. This, however, does not pose any problem in industrial process control applications, where all the signals are anyway brought to or originate from a central control room. An additional feature which makes the scheme very attractive is the fact that its computational complexity is about the same as that of a totally decentralized one