Linearized PI controller for real-time delay dominant second order nonlinear systems

The objective of this paper is to design a robust PI controller for a second order system plus delay (SOSPD) which has an inherent nonlinearity by the virtue of its structural dynamics. An example of Dual Spherical Tank Liquid Level System (DSTLLS), which is non linear, has been chosen to analyse the performance of the robust PI controller designed. The DSTLLS has been linearized and modelled using black box modelling technique by performing the real-time experimentation and the performance of the applied controller has been analysed in simulation by MATLAB Simulink. This paper also discusses about the simulation efficiency using the performance indices like Integrated Squared Error (ISE) and Integrated Absolute Error (IAE).