Two-degree-of-freedom Controllers for Double Integrating Systems with Time Delay and Unstable First Order plus Time Delay Systems with an Integrator

In this paper, design of two-degree-of-freedom Proportional Integral and Derivative (PID) controller for Double Integrator with Time Delay systems and Unstable First Order plus Time Delay systems with an Integrator is proposed. The robustness of the proposed controller for uncertainty in model parameters is evaluated considering one parameter at a time using Kharitonov's theorem. The stability region for all model parameters is evaluated for the proposed controller and compared with the controllers designed by recently reported methods. The proposed controller is applied to various transfer function models and the performance comparison of the proposed controller is made with the PID controllers designed by recently reported methods to show the efficiency of the proposed controllers.