Design of Fractional Order Pi Controller for First Order Plus Dead Time Process Based on Maximum Sensitivity

In this paper set of tuning rules for fractional order PI controllers has been presented for first order plus dead time process (FOPDT). The tuning rules have been developed by minimizing the integrated absolute error (IAE) for load disturbance rejection with a constraint on the maximum sensitivity eMs). The fractional order term of the PI controller λ has been taken as 0.9, 1.1 and 1.2 and parameters of PI controller has been obtained by minimizing IAE for FOPDT system by using genetic algorithm. Finally, the tuning rule is devised in terms of Ms. The effectiveness of proposed method has been verified by various examples taken from literature.