Multi-motor drive optimal control using a fuzzy model based approach

Multi-motor drives, the typical examples of which are continuous lines for tension processing of various materials, are complex and coupled MIMO nonlinear systems, the parameters of which are difficult to identify. This paper presents the design of optimal control of a continuous production line using a fuzzy model based approach with emphasis on minimal knowledge on the controlled technology. In the first part of the paper we describe the method of the black-box fuzzy model design based only on the system's measured input/output data without the necessity of preliminary knowledge of its internal structure and parameters. This fuzzy model is in the second part used in the design of optimal parameters of a PI controller of continuous line on basis of the chosen quadratic optimality criterion. The realized experimental measurements on a continuous line physical laboratory model confirmed the effectiveness and the good dynamic properties of the proposed optimal controller and also its applicability to MIMO nonlinear dynamic systems with as little previous knowledge as possible. In order to demonstrate its effectiveness, the performance of the designed controller is compared with that of a conventional controller and a classic fuzzy controller designed on the basis of linguistic rules.