A Modified Repetitive Control Strategy for Nonlinear Systems | Chapter 13 | Current Research in Science and Technology Vol. 3
In this research work, a new attempt is made to implement a Modified Repetitive Control Strategy (MRCS) directly in a Liquid Level System (LLS) and indirectly in a Spherical Tank Level System (STLS). The dynamics of the both level processes are described by the worst case model parameters which are identified by influencing the step test method. In direct approach, MRCS is incorporated in the conventional liquid level control loop of proportional (P) mode. Ziegler-Nichols Tuning Rule (ZNTR) based proportional controller parameter is considered in the loop. A periodic signal of sine wave in inflow to the level system is generated and real time runs of the LLS are carried out for the periodic input tracking with MRCS based P mode control loop. In indirect approach, by utilizing relay feedback technique, the periodic reference signal of MRCS is generated. From the input and output chattering signals of the MRCS, the optimized PI controller parameters are identified using Recursive Least...