PID

Industrial PID controllers: tutorial (CZ)04.03.2009

Robust PID autotuner: Method of moments (CZ)26.02.2009

One point relay identification experiment based on constant-phase filter04.06.2008
Using standard relay identification methods, one obtains a critical frequency response point with the phase shift 180 degrees. Such phase is not optimal for consequential PI(D) controller design especially when there is no additional knowledge about the process. This paper presents a new low-order filter providing arbitrary constant phase at about three decades. Such filter embedded into relay tuner shortens the experiment significantly and helps to identify the sample with arbitrary phase shift. The authors believe that presented approach may lead to improvement of existing relay autotuners.

Robust PID controller design from constrained step response (CZ)07.03.2007

Fractional-order PID controller design on Internet: www.PIDlab.com06.11.2006
The fractional-order PID controller (FPID) arises from the classical one after considering integrator and derivator of arbitrary real order. This paper describes the simple Internet tool for FPID design - the Java applet free accessible on www.PIDlab.com.

The fractional-order PID controller outperforms the classical one06.11.2006
The three-parameter PID controller is the most popular industrial controller thanks to its simplicity. Only two more parameters arise after considering the integrator and derivator of arbitrary real order. Such a generalized controller is called fractional-order PID controller (FPID).

Robust design of PID controller from process static gain and one point of frequency response28.08.2006
The first aim of this paper is to present an explicit parametrization of the value set boundary for a process-control-oriented model family consistent with the process gain and one point of the process frequency response obtained from a relay experiment. The second aim is to develop new PID design rules based on this parameterization. Moreover, the design procedure is converted to the suitable form for autotuning purposes.

Design of H-infinity PI controller by robustness regions method17.06.2005
This paper presents the complete analytical solution of the mixed sensitivity design problem for general SISO systems and the PI controller.

Iterative feedback tuning of PID controller17.06.2005
This paper is focused on iterative tuning of the 2DOF PID controller to minimize given quadratic cost function of the system output error and control effort.

Exact revision of the Ziegler-Nichols frequency response method17.06.2005
The main subject of this paper is to provide an exact theoretically-based revision of the Ziegler­Nichols frequency-response method by solving the newly formulated robust design problem. It is shown that the original method can be considerably improved if a suitable point on the Nyquist curve is used instead of the ultimate point

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