An improved algorithm for automatic tuning of PID controllers

For the automatic tuning of PID controllers, a new identification algorithm is proposed to identify frequency data sets of the process. It guarantees better accuracy and can provide much more frequency data sets of the proces s than the previous describing function analysis algorithms. The identifica tion method provides exact data sets for all desired frequencies and it als o gives the exact data set corresponding to the relay frequency even in the presence of a static disturbance. (C) 2000 Elsevier Science Ltd. All right s reserved.