Split-range control of a Jacketed CSTR using self-tuning fuzzy PI controller

CSTR is a highly non-linear process and the nonlinear behavior of such processes requires other methods than conventional control. This paper addresses a novel application of Self-tuning Fuzzy PI Controller (STFPIC) to a Split-range Control strategy for circulation of cold fluid or hot fluid through Jacketed Continuous Stirred Tank Reactor (CSTR) in cascade control mode. In the primary loop STFPIC was used while in the secondary loop conventional proportional controller was implemented. Self-tuning mechanism of fuzzy PI controller is implemented with the help of a gain multiplier whose value is updated based on the instant error and rate of change of error. Grey Wolf Optimizer is used for tuning of primary as well as secondary controller gains in order to reduce Integral of Absolute Error (IAE). The overall approach has been simulated in LabVIEW™ environment and a comparative study of STFPIC with conventional PID controller have been presented in this paper. Based on the intensive simulation studies it is found that the STFPIC outperformed PID for set-point tracking by 62.5% and for disturbance rejection by 63.4%, in terms of IAE.