Gray-Box Modeling of Processes with Output Multiplicities

Abstract This paper introduces block-oriented modeling approaches to the development of NARMAX models for processes exhibiting output multiplicities. "Feedback block-oriented" model structures are introduced which can force the resulting NARMAX model to have a particular steady-state behavior and reduce the model identification problem to a constrained linear model identification. These models are particularly suitable for gray-box modeling approaches where it is assumed that the steady-state behavior of the process is known and a NARMAX model is sought to approximate its dynamic response.