Maximum sensitivity-based PID controller cascaded with 2/3 order filter for integrating processes with time delay

In the chemical industry, integrating processes are often encountered. Examples of integrating processes include bottom level control of a distillation column, level control of a tank with a motor fixed at the outlet, current-controlled DC motor, fermentation reactors, spacecraft take-off dynamics, paper industry drying processes, continuous stirred tank reactor (CSTR) with exothermic reactor, and so on. This article describes a new PID controller with a 2/3 order filter for integrating processes with time delay. Time delay is approximated to ratio of two polynomials using a second-order Pade’s approximation. A set point filter is used to minimize overshoot and the settling time of servo responses. Simulation studies are conducted on some of the benchmarking process models utilized in the literature. The comparative assessment is based on various performance indices.