Relaxed Ziegler-Nichols Closed Loop Tuning of PI Controllers

Modeling, Identification and Control

关键词: PI controller;    tuning;    open loop;    closed loop;    Ziegler-Nichols;    Tyreus-Luyben;    Skogestad;    relay-tuning;    performance;    stability;   

DOI  :  10.4173/mic.2013.2.4

来源: DOAJ

【 摘 要 】

A modification of the PI setting of the Ziegler-Nichols closed loop tuningmethod is proposed. The modification is based on a combination of the Skogestad SIMCtuning formulas for ''integrator plus time-delay'' processes with the Ziegler-Nichols tuning formulas assuming that the process is modeled as an ''integrator plus time-delay'' process. The resulting PI settings provide improved stability margins compared with those obtained with the original Ziegler-Nichols PI settings. Compared with the well-known Tyreus-Luyben PI settings, the proposed PI settings give improved disturbance compensation. For processes with zero or a negligible time-delay, but with some lags in the form of time-constants, tuning based on ultimate gain and ultimate period may give poor results. Successful PI settings for such processes are proposed.

【 授权许可】

Unknown