Takagi Sugeno Fuzzy-Tuned RTDA controller for pH Neutralization process Subject to Addictive Load Changes

Abstract

For the control of pH value in neutralization process, three closed-loop control schemes are designed in this work, namely Proportional–Integral Derivative (PID), model predictive control (MPC) and Robustness Tracking Disturbance Overall Aggressiveness (RTDA) controller. As the title of the paper implies, the neutralization process undergoes addictive changes in its process parameters that clearly indicate the necessity of introducing this advanced control technique for this process. RTDA controller is a next generation regulatory controller which is an alternative to the popular PID control scheme. It combines the simplicity of the PID controller with the versatility of MPC. The pH neutralization is a highly non-linear and time-varying process, which has different operating regimes. The control objective in neutralization process is to sustain pH value at the prescribed level by controlling the flow rate of both acid and base. Takagi Sugeno (TS) Fuzzy-Tuned RTDA controller is employed for this process to vary the controller parameters for each operating point so that the set-point can be tracked effectively in all the operating regimes. An additive load disturbance is applied in the flow rate of acid and base to obtain the regulatory response. Thus, the paper focuses on effective disturbance rejection in each operating region and robustness in tracking the desired output. The simulation results are compared using time domain specifications, computational time and performance index like integral square error (ISE).