Optimal dead-time compensator design for stable and integrating processes with time delay

Enhanced IMC design of load disturbance rejection for integrating and unstable processes with slow dynamics

“…To reject a ramp-type load disturbance occurring at the process input side, which may be described in the form of a double integrator, an additional asymptotic constraint along with (13) and (14) to guarantee no steady offset of the process output is required as lim s→0 d 2…”

“…According to the IMC-based control method [19,21], asymptotic constraints in (14) and (27) should be satisfied to guarantee internal stability and no steady offset of the process output. The desired closed-loop transfer function for load disturbance rejection may be correspondingly determined as…”

“…Further enhanced SP control methods can be seen in the recent Refs. [5][6][7][8][9][10][11][12][13][14]. For unstable processes, modified SP control schemes have also * Corresponding author.…”

Simple Formulae for Control of Industrial Time Delay Systems

“…Since most of the PID-based methods, are based on the Pade' approximation of the time delay term, they provide poor performance when long time delays are involved (Tan, Marquez and Chen, 2003;Vanavil, Chaitanya and Seshagiri Rao, 2015). Similarly, many methods which are based on the internal model principle, are also based on the Pade' approximation and, therefore, provide acceptable disturbance rejection and reference tracking properties only for rather small time delays (Jin and Liu, 2014;Liu and Gao, 2011;Tan et al, 2003;Vanavil et al, 2015;Zhang, Rieber and Gu, 2008). Considering the well-known drawbacks of the existing methods, the objective of this paper is to provide a simple control structure with straightforward tuning guidelines, in which the closed loop performance and stability are guaranteed.…”

Repetitive control approach towards automatic tuning of Smith predictor controllers

“…Many studies on this classical control scheme have been done, especially in the last two decades to enhance its practical applications in the industry. Some have addressed the issues of robustness [6][7][8] while others have proposed various tuning techniques [9][10][11][12][13] to facilitate the use of the Smith predictor as simply as the PID controller.…”