Abstract:

A stabilizing space based multi-objective genetic algorithm (MOGA) was proposed to optimize PID controller parameters for the unstable first order plus time delay (FOPDT) plants.Two-controller structure was first adopted to guarantee that the stabilization spaces of PID controller parameters could be obtained by generalized Hermite-Biehler theorem for unstable FOPDT process.Based on the stabilizing space, a multi-objective genetic algorithm was put forward to solve the constrained multi-objective optimization problem for PID controller parameters tuning.Several numerical examples and simulation of unstable bioreactor were performed to verify the efficiency of the proposed method.