A simple method of tuning PID controllers for integrator/dead-time processes

A simple method is proposed for PI, PD and PID controller settings for an integrating plus dead-time transfer function model. The method is based on matching the coefficients of corresponding powers of s in the numerator and that in the denominator of the closed-loop transfer function for a servo problem. The derived controller transfer function is found to be a PID controller which is recently also shown by Visioli [IEE Proc. Control Theory Appl. 148 (2001) 180] by minimizing the integral squared error (ISE) using a genetic algorithm. It is shown that the PID controller gives offset for regulatory problems. A method is proposed for designing PI and PID controllers. The performance of the PID controller is shown to be better than that proposed by Visioli. A set-point weighting parameter is used to reduce the overshoot for the servo problem. (C) 2002 Elsevier Science Ltd. All rights reserved.