Optimal PID controller design for a class of delay fractional-order systems

Control of fractional-order systems has attracted more and more attention in many fields. Time delay is an inherent phenomenon in the real process, but the control techniques available for fractional-order system with time delay cannot guarantee the robustness and the control performance. In this paper, stabilizing and optimal PID controller tuning methods are proposed for delay fractional-order systems. The requirements on both robust stability in frequency domain and transient performance in time domain are met. Comparisons are made among four stabilizing and optimal controllers to reveal the relationship between the tuning parameters and control performance via simulation tests.