International Journal of Engineering and Technology

One of the main problem in process industries is to control process parameters due to their nonlinear behaviour. Control in the level of liquid in a nonlinear spherical tank is challenging due to variation in the cross section area with height. This paper is about the controlling of liquid level in a nonlinear Dual Spherical Tank Liquid Level System (DSTLLS) using Gain Scheduled PI controller (GPIC).The performance indices like ISE, IAE and time domain calculations similar to rise time, peak time and settling time are also calculated in this paper, for different servo and regulatory tracking cases. This research paper gives details about implementation and performance analysis of real time GPIC for DSTLLS by using LabVIEW.