Modeling and LPV control of web winding system with sinusoidal tension disturbance

In this paper, the nonlinear model of a flexible web winding system composed of three motors and two load cells is derived based on the general laws of physics. The model parameters are identified using optimization methods. LPV controller is designed to obtain good reference tracking properties as well as to properly reject sinusoidal disturbance for suppressing vibrations.The frequency of disturbance is constant or time-varying and unknown but measurable. The proposed approach is based on a time-varying frequency weighting function giving an extended linear parameter varying (LPV) model that is used to design a stabilizing LPV Hinfin controller. The method is applied to the flexible web winding system to compensate the web tension disturbance caused by the sinusoidal vibration on unwinder.