Digitization of continuous interval transfer functions: A revisited method and its application on a case study

A method that uses the Boxer-Thaler integrator to obtain an approximate discrete-time transfer function for uncertain continuous systems with interval uncertainties is revisited. The advantage of the approach lies in the fact that the interval structure of the continuous system is preserved in the resulting discrete model. This allows the application of existing robust results to the discretized system and minimize the search space in the uncertainty region. The method is also applied to a control loop from a multi-sidestream distillation column.