TRACKING CONTROL OF JOIN-FREE TIMED CONTINUOUS PETRI NET SYSTEMS

A new low-and-high gain algorithm is presented for tracking control of timed continuous Petri Net (contPN) systems working under infinite servers semantics. The inherent properties of timed contPN determine that the control signals must be non-negative and upper bounded by functions of system states. In the proposed control approach, LQ theory is first utilized to design a low-gain controller such that the control signals satisfy the input constraints. Based on the low-gain controller, a high-gain term is further added to improve the system transient performance. In order to guarantee global tracking convergence and smoothness of control signals, in our work, a new mixed tracking trajectory (state step and ramp) is utilized instead of a pure step reference signal.