Tuning of PID Controller for a Nonlinear Conical Tank

Abstract

This paper is about comparison between PID tuning method and PI predictive control in the conical tank process. The level control becomes quite typical due to the nonlinear shape of tank. Many process industries use conical tanks because of its shape contributes to better drainage of solid mixtures, slurries and viscous liquids. So control of conical tank presents a challenging problem due to its non-linearity and constantly changing cross-section. A conventional PID controller is used to control the conical tank system based upon tuning rules. From the knowledge of ultimate gain and ultimate frequency, we can obtain the tuning parameters by using ZN-Closed loop method.  Predictive PI control (PIP) has the advantage that it manages to predict the measurement signal even when the process has along dead time and when the measurement signal is noisy.