Active damping injection controller for web longitude and tensions of nonlinear roll-to-roll systems

This study presents an advanced algorithm for controlling the web longitude and tension of nonlinear roll-to-roll systems in the form of a cascade structure. Parameter variation and disturbance attenuation problems are addressed systematically. The features of this article are divided into two parts. First, active damping terms are injected to stabilize the system nonlinear dynamics so that the first-order closed-loop transfer functions are obtained for each loop via pole-zero cancelation. Second, disturbance observers are introduced to ensure the performance recovery property by attenuating the disturbances from the model-plant mismatches. The closed-loop system is numerically emulated using MATLAB/Simulink to show the effectiveness of the proposed technique.