Reformulation of the tangent method for PID controller tuning

Process stability of a PID control loop depends upon the proportional, integral and derivative constants used. Using the conventional tangent method and the proper tuning rule, the optimum P, I and D can be estimated. With this optimum P, I and D set into the controller, an optimum response is normally achieved. A new reformulation of the tangent method is proposed in this paper where the analysis is made simpler, easier and faster. The new reformulated tangent method can be applied with ease to any recording or display devices as compared to the existing tangent method as will be shown in the experimental study section.