Control of delayed systems with two unstable poles using a multi-predictor based strategy

The stability analysis of linear systems with time delay is difficult because the delay term appears in the characteristic equation when closing the loop inducing an infinite order system. In this work a strategy based on a multi-predictor for linear delayed systems with two unstable poles is proposed. This strategy allows to estimate the system signal before been delayed in order to use it in the control stage. The great advantage of the multi-predictor is that it can be used for this type of systems with any delay size. Also, the necessary and sufficient stability conditions for the multi-predictor scheme are obtained and the minimum number of sub-predictors necessary to have an adequate estimation of the signal is determined. Finally, to show the effectiveness of the proposed strategy, a simulation example is presented.