Automation of two interacting conical tank process with multiobjective optimization of fractional PID controller with a metaheuristic optimizer, the cuckoo search algorithm

Industrial process loops are mostly interacting in nature. Automation of multi-input-multi-output interacting process involves tedious multiloop PID control design procedure. With the growth of fractional calculus in the field of automation, fractional order PID controller is attempted in this paper. Tuning of the controller parameters involves getting the process model, interaction analysis, tuning the controller parameters between the highly interacting loop and detuning the controller parameters. The design complications can be reduced by simple online tuning of the controller parameters using metaheuristic optimizer. There are many metaheuristic optimizers like bee colony optimizer, ant colony optimizer, cuckoo algorithm, bat algorithm, etc. In the present research work, cuckoo algorithm is used to obtain the multiloop PID controller parameters. The multi-objective optimization function considered in this case involves weighted integral time absolute error of individual loops combined together. The performance is validated by analysing the response for set point change and disturbance rejection.