Robust Stability Based Pid-Controller Design of D.C. Servo Plant with Time-Delay and Additive Uncertainty

The area of control system engineering that mainly deals in obtaining the robustness of system in the existence of uncertainties is known as robust control. In this paper, a graphical design method is developed for obtaining the entire range of PID controller gains that stabilize a D.C. servo plant robustly with the existence of time delays and additive uncertainty employed. This method of design mainly works on the frequency response of the system, which can provide to decrease the complexities implicated in servo plant modeling. In fact in the real time processes, the time-delays and parametric uncertainties are more or less always present, that makes our controller design method crucial for process control. We have used this graphical method of design to find the robust stability of a DC servo plant model with a delay in communication and additive uncertainties. The results were found satisfactory and robust stability has achieved for the said model.