Sliding Mode Control for a Conical Tank: Empirical vs. Coordinate Transformation Linearization Comparison

Abstract

In this document, two linearization techniques are applied to level control in a conical tank. Also, this control represents a significant challenge because of a constantly varying section with height and its nonlinearity, so many control schemes were carried out. To obtain the linear model for the conical tank, first technique is the empiric linearization from data of the process. The reaction curve method is used, and the characteristic parameters are obtained. Another method is the coordinate transformation in the system is decomposed into two nonlinear functions g(x) and q(v,x). Consequently, using both linearization procedures, a sliding mode controller is designed and applied to a conic tank to compare the performance obtained from each technique. The proposed controller shows robustness and rejects the disturbances better than the typical PID controller.