Comparison of Various PI/PID Controller Design Methods for Interacting Multiloop Systems

The main obstacle encountered in the design of multivariable controller systems is the phenomenon of the interactions between the loops. Many methods are proposed to design and tune controller parameters in the interacting multivariable processes. Recently, some methods are introduced which based on concept of effective open-loop transfer function to decompose a multiloop control system into a set of equivalent independent single loops. In this paper, one technique of each ordination decentralized multivariable controller are selected and compared together. Several illustrative examples are applied to specify the advantages and weaknesses of each method.