A Controller with Adjustable Dead Time Compensation

In this work, a Smith predictor enhanced PID controller, the SP-PID, is pro-posed. A tuning parameter K sp is devised which gradually transforms the controller from a PID controller into a Smith predictor as K sp changes from 0 to 1. The Properties of the SP-PID are explored and the design procedure is to ensure a certain degree of robustness. Simulation results clearly indicate that the SP-PID takes advantage of the SP when a small modeling error is encountered and it is gradually detuned to a PID controller, a user friendly controller, when the model quality degrades. Moreover, the proposed concept can be implemented to current process control computers with virtually no extra hardware cost.

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