Robust observer-based control of an aluminum strip processing line

Tension control of an aluminum strip in a strip processing line is the focus of this paper. A continuous strip processing line is truly a large-scale complex interconnected dynamic system with numerous control zones to transport the strip while processing it. In this paper, two aspects affecting the tension behavior of the strip in the entire processing line have been studied. First, a model that accurately represents the dynamics of the strip in accumulator spans is derived from the first principles. Second, an estimated decoupled state feedback controller is designed for the linearized dynamics of controlled spans. The state estimates are obtained using a Luenberger observer. Convergence of the state and estimation errors is shown. Some remarks on detection of actuator faults using a linear observer for interconnected systems are also given.