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Robust Controllers (robust + controllers)

Distribution by Scientific Domains
Engineering75%

Selected Abstracts

Dynamic COI-tracking concept for the control of generators in multi-machine power systems

EUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 1 2008
Zhou Lan
Abstract In the conventional excitation control concept, the power angle and frequency of a generator are driven to a pre-designed operation point after the fault occurs. It is named as Constant Point Stabilization (CPS) concept in this paper. A novel concept, called dynamic Center of Inertia (COI)-tracking concept is proposed in this paper. In the concept, the power angle and frequency of each generator track the dynamic COI of the power system. Compared to CPS concept, a salient feature the suggested dynamic COI-tracking concept has is that the generators are not restricted to constant angle point or frequency any longer but track the dynamic COI trajectory of the system to keep synchronous in rotor angle and frequency. Wide area measurement system (WAMS) will be used to transform COI signals to each generator. The time delay within a certain limit of WAMS signals is permitted. To make comparison between the two concepts, the control system models based on the two concepts are first established. Then, using the back-stepping method, two robust controllers are designed to achieve the control objectives of the two concepts. At last, dynamic simulations are carried out based on a 2-area-4-machine test power system, and the control effects of the two controllers, together with that of the conventional AVR,+,PSS excitation system, are compared. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Robust control of depth of anesthesia

INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 5 2009
Guy A. Dumont
Abstract This paper presents a systematic procedure to design both robust PID controllers and robust controllers based on fractional calculus (based on Commande Robuste d'Ordre Non Entier, or CRONE methodology) to regulate the hypnotic state of anesthesia with the intravenous administration of propofol. The objective of the controllers is to provide an adequate drug administration regimen for propofol to avoid under or over dosing of the patients. The controllers are designed to compensate for the patients inherent drug,response variability (uncertainty), to achieve good output disturbance rejection, and to attain good set point response. The performance of the controllers is assessed by calculating typical time domain measures and using the median PE, median absolute PE, divergence, and wobble. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Adaptive control for edge alignment in polyester film processing

ADVANCES IN POLYMER TECHNOLOGY, Issue 3 2007
Chang-Chiun Huang
Abstract Edge alignment of polyester (PET) films is important for achieving product quality and processing speed in winding, coating, drying, and other processes. The edge alignment can be achieved by lateral deflection control, provided that the film tension and transport speed are even at desired values. This article aims to correct the lateral deflection of films by designing robust controllers to swivel the guiding rollers and to maintain even tension and speed at target levels. The self-tuning neuro-proportional integral derivative controller and adaptive high-gain output feedback controller are adopted to guide the lateral deflection so that the film aligns at the desired position. A control scheme, neuron controller by associative learning, is used for maintaining tension and speed control. These strategies are applied to a simplified PET film processing system. The experimental results demonstrate that in our setup, the control schemes can effectively alleviate not only the lateral deflection but also the tension and speed fluctuation at target levels. © 2008 Wiley Periodicals, Inc. Adv Polym Techn 26:153,162, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20096 [source]

Robust force control of a flexible arm with a nonsymmetric rigid tip body

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 5 2001
Yoshifumi Morita
In this article, we discuss modeling and robust control of bending and torsional vibrations and contact force of a flexible arm with a nonsymmetric rigid tip body. By using Hamilton's principle and the Lagrange multiplier method, dynamic equations of the constrained flexible arm are derived. Since the flexible arm has the nonsymmetric tip body, the bending and torsional vibrations are coupled. As the obtained boundary conditions of the distributed parameter system are nonhomogeneous, we introduce a change of variables to derive homogeneous boundary conditions. By using the eigenvalues and the correpsonding eigenfunctions related to the distributed parameter system, we derive a finite-dimensional modal model. To compensate for the spillover instability, we construct robust controllers of an optimal controller with a low-pass property and an H, controller. Some experiments have been carried out to show the effectiveness of the proposed robust controllers. © 2001 John Wiley & Sons, Inc. [source]