Control design for dual mode operation in large scale multivariable systems

Designing fixed order controllers for multivariable systems is one of the most important and challenging problems in process industries. Simple control design techniques, which are applicable to a wide range of small and large scale processes, must be developed. With this motivation, a decoupling control design method well suited for large scale systems is proposed in this manuscript. The proposed design despite being simple, not only ensures effective performance but also accounts for the closed loop integrity and robustness requirements. The proposed method allows operation in dual modes viz. decoupling and decentralized, with the same controller settings. This facilitates seamless switching between the two modes. Simulations have been performed on various benchmark multivariable processes to verify the wide applicability, superior performance, and robustness of the proposed method.