Decentralized Robust Control Strategies with Model Based Feedforward for ElasticWebWinding Systems

Demand for improved performance under a wide variety of dynamic conditions and web materials are placing additional emphasis on developing new advanced control strategies. This paper presents decentralized H_infin controllers with model based feedforward for web winding systems which provide improved web tension and velocity regulation in the presence of uncertainties. First, mathematical models of fundamental elements in a web process line are presented. A new state space model is developed which enables calculation of the phenomenological model feedforward signals and helps in the synthesis of decentralized H_infin controllers around the set points given by the reference signals. Different H_infin control strategies with additive feedforward have been validated on a nonlinear simulator identified on a 3-motor winding test bench