An automatic pid controller tuning method by frequency response techniques

An alternative Ziegler-Nichols (1942) controller tuning technique was proposed in this study. Under the proportional control of a single-loop control system, an arbitrary pulse testing in the set point was introduced to the system. The ultimate frequency and gain could both be directly calculated from the transients by frequency response techniques without any trial and error procedures. PID controller settings were thus obtained according to the Ziegler and Nichols' rules. Furthermore, this technique was extended to the tuning of a cascade control system. A procedure for simultaneously tuning the primary and secondary controllers with both loops in proportional control from a single pulse testing also is presented. On propose dans cette etude une technique alternative de Ziegler-Nichols (1942) pour le reglage des contrǒleurs. Sous le contrǒle proportionnel d'un systeme de regulation a boucle unique, un essai d'impulsion arbitraire au point de consigne a ete introduit dans le systeme. La frequence et le gain ultimes peuvent tous deux etre directement calcules a partir des transitoires par des techniques de reponse des frequences sans procedures d'essais-erreurs. Le reglage des contrǒleurs PID a ete ainsi obtenu conformement aux principes de Ziegler et Nichols. De plus, cette technique a ete etendue au reglage d'un systeme de regulation en cascade. On presente egalement une methode de reglage simultanee des contrǒleurs primaires et secondaires dont les deux boucles sont en contrǒle proportionnel a partir d'essais d'impulsion simples.