Repetitive controller for a nonlinear liquid level system

In this work, the Repetitive control strategy is applied to the nonlinear liquid level system for tracking the periodic reference trajectory. Here, the repetitive controller is compared with other conventional controllers for tracking the periodic reference signals applied at the set point or to reject the periodic disturbances. The periodic signal of sine wave is generated and given at the inflow. The performance analysis is done based on the tracking error and square error. The simulation is done using MATLAB - SIMULINK. From the simulation results, it is obvious that the repetitive controller along with the conventional controller can give better tracking of periodic signals compared to other conventional controllers. The results are given in both time domain and frequency domain.