Robust Tuning of PI Controller for IPDT Plant

By considering robust tuning of the PI controller for uncertain Integral Plus Dead Time plant (IPDT) this paper demonstrates possibilities of the new Matlab/Simulink tool based on the performance portrait method enabling for plants with parameters defined over uncertainty intervals to guarantee transient responses with specified deviations from ideal shapes at the plant output and input and fulfilling additional optimality specification, defined e.g. in terms of the minimal IAE values for the setpoint and disturbance steps, in terms of the maximal integral gain, etc. In difference to the robust tuning methods of the 1st generation considering typically controller parameters calculated from plant parameters specified by a single entry, in this new method uncertain plant parameters are specified by two entries characterizing their extreme values. As the ideal step responses at the plant output monotonic transients are considered, whereas at the plant input one-pulse step responses consisting of two monotonic intervals are supposed.