2DOF Robust PID Controller Design for Industrial Large Time-constant Plus Dead-Time Processes

Large variant of industrial processes have been classified as large time-constant with dead time processes. Even though, with P or PD controller, these processes demonstrates a good set-point tracking, a poor load disturbance rejection is observed. While, using an integral action leads to large overshoot in set-point tracking with poor robustness. In this work, a 2DOF PID controller is proposed for industrial large time-constant plus dead-time processes. Controller design have been carried out with second order damping analysis, gain margin and phase margin specification. To demonstrate the superiority of the proposed controller, simulation comparison have been presented. Moreover, performance and robustness analysis of the example have been shown on the basis of ISE, ITAE, IAE and Maximum sensitivity (Ms).