State Prediction for a Class of Time-Delay Unstable Linear Systems

This papers deals with the state prediction of a class of linear time delay systems with delays at the input and at the state and considering that the open loop system is unstable. In order to deal with this problem, it is proposed a Smith predictor compensator type that results in a generalization of a previously reported compensator used to obtain the approximate prediction of the state of a system of the same class that it is assumed to be open loop stable. In the present case, of unstable plants, it is shown that the proposed compensator allows also to approximately estimate the future values of the estate and that the estimation error converges to zero due to the consideration of an additional internal feedback. The performance of the proposed compensator is evaluated by means of numerical simulations.