Novel fuzzy fractional order PID controller for non linear interacting coupled spherical tank system for level process

摘要

In this paper, a novel Fuzzy Fractional Order Proportional Integral Derivative (FFOPID) controller is proposed to control the liquid level of Two Tank Spherical Interacting System (TTSIS). Spherical tanks are widely used in process industries due to its high storage capacity. These are non-linear due to its varying surface area with respect to its height and hence the level control of a spherical tank system is a challenging task. Fractional Order Proportional Integral Derivative (FOPID) controller is designed for a liquid level control of a spherical tank which is modelled as a fractional Order System. The performance indices such as rise time, settling time, peak time and peak overshoot are analysed for the proposed control scheme and compared to conventional controllers such as PI, PID, PID-SMC, FOPID. Moreover the time integral performance measures such as ITAE, IAE and ISE are analysed. Experimental results are shown to validate the obtained results with those of simulations. It has been proven that FFOPID outperforms all other existing techniques in terms of various time domain specifications and time integral performance measures. (C) 2019 Elsevier B.V. All rights reserved.