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Murilo E. C. Bento - One of the best experts on this subject based on the ideXlab platform.
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Design of a wide-area damping Controller to tolerate permanent communication failure and time delay uncertainties
Energy Systems, 2021Co-Authors: Murilo E. C. BentoAbstract:The wide-area damping Controllers showed to be effective in improving the damping ratio of the low-frequency oscillation modes. This Controller requires remotes signals sent by Phasor Measurement Units located in different positions of the power system and, then, these signals are highly susceptible to communication time delays, failures and cyber-attacks that may compromise Controller performance. This paper presents a procedure based on particle swarm optimization to tune the parameters of the Central Controller. Considering a set of operating conditions, the proposed procedure will search the Central Controller parameters that maximize the damping ratio of all eigenvalues of the linear model. A strategy to deal with permanent communication channel failures and time delay uncertainties in a given interval will be included in the proposed model and procedure. Then, the resulting Central Controller will present robustness to multiple operation conditions of the power system, to time delay uncertainties and to permanent failure of the channels of the Controller. The proposed procedure was carried out in the IEEE 68-bus system and the performance of the designed Controller was evaluated by modal analysis and time-domain nonlinear simulation.
Murilo Eduardo Casteroba Bento - One of the best experts on this subject based on the ideXlab platform.
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A procedure to design wide-area damping Controllers for power system oscillations considering promising input–output pairs
Energy Systems, 2019Co-Authors: Murilo Eduardo Casteroba BentoAbstract:The expansion of the wide-area measurement system has provided some control strategies to improve the low-frequency oscillation modes in electric power systems. One of these strategies is to use remote signals for a wide-area damping Controller (WADC) to enhance the small-signal stability of the power system. However, the expansion of the Electric Power System increased the generator number connected to the grid, and then some challenges to the WADC design surged such as which input–output pairs of the WADC should be designed to improve the closed loop system damping. Typically, the WADC is a Centralized Controller and may have many design elements. The interactions among the elements may compromise the Central Controller design and its purpose. This paper proposes a procedure based on genetic algorithms in order to design a robust Central Controller. This procedure automatically chooses the input–output pairs of the Central Controller that will contribute to damping the low-frequency oscillation modes. The design procedure considers topological changes and time delay variations. Small-signal analysis and time-domain nonlinear simulations are carried out in the multi-machine Australian Equivalent Power System, an IEEE benchmark model for small-signal stability analysis.
Kenji Sunagawa - One of the best experts on this subject based on the ideXlab platform.
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Sensitized Central Controller of ventilation in rats with chronic heart failure contributes to hyperpnea little at rest but more during exercise.
2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006Co-Authors: Tadayoshi Miyamoto, Toru Kawada, Masashi Inagaki, Masaru Sugimachi, Hiroshi Takaki, Atsunori Kamiya, Toshiaki Shishido, Kenji SunagawaAbstract:BACKGROUND: To understand the pathophysiologic basis of exercise hyperpnea in chronic heart failure (CHF), we have developed an experimental method quantitatively characterizing ventilatory regulation system in rats. An equilibrium diagram illustrates the characteristics of two subsystems, i.e., the Central Controller (arterial CO2 tension [Pa(CO2)] to minute ventilation [V(E)] relationship) and peripheral plant (V(E) to Pa(CO2) relationship). In this study, we compared these between normal and CHF rats at rest. METHOD: In anesthetized 6 postinfarction CHF rats and 6 normal rats, we induced hypercapnia by changing inspiratory CO2 fraction and measured the steady-state Pa(CO2) to V(E) relation. We altered V(E) by varying the level of artificial ventilation and measured the V(E) to Pa(CO2) relation. RESULTS: Central Controller gain S was significantly lager in CHF rats, confirming clinical observation. The V(E) at rest (operating point) in CHF was 24% larger; Central hypersensitivity, however, contributed little (6%) to this increase. CONCLUSION: Central hypersensitivity alone would not explain hyperpnea at rest in CHF rats. Considering the right and upward shift of V(E) to Pa(CO2) relation, Central hypersensitivity contributes more to hyperpnea during exercise. The potential difference between normal and CHF rats in exercise-induced changes in Controller and plant should be examined to fully understand the mechanism of exercise hyperpnea and to develop a method to attenuate this.
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Sensitized Central Controller of Ventilation in Rats with Chronic Heart Failure Contributes to Hyperpnea Little at Rest but More during Exercise
2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006Co-Authors: Tadayoshi Miyamoto, Toru Kawada, Masashi Inagaki, Masaru Sugimachi, Hiroshi Takaki, Atsunori Kamiya, Toshiaki Shishido, Kenji SunagawaAbstract:To understand the pathophysiologic basis of exercise hyperpnea in chronic heart failure (CHF), we have developed an experimental method quantitatively characterizing ventilatory regulation system in rats. An equilibrium diagram illustrates the characteristics of two subsystems, i.e., the Central Controller (arterial CO2 tension [PaCO2] to minute ventilation [VE] relationship) and peripheral plant (VE to PaCO2 relationship). In this study, we compared these between normal and CHF rats at rest. In anesthetized 6 postinfarction CHF rats and 6 normal rats, we induced hypercapnia by changing inspiratory CO2 fraction and measured the steady-state PaCO2 to VE relation. We altered VE by varying the level of artificial ventilation and measured the VE to PaCO2 relation. Central Controller gain S was significantly lager in CHF rats, confirming clinical observation. The VE at rest (operating point) in CHF was 24% larger; Central hypersensitivity, however, contributed little (6%) to this increase. Central hypersensitivity alone would not explain hyperpnea at rest in CHF rats. Considering the right and upward shift of VE to PaCO2 relation, Central hypersensitivity contributes more to hyperpnea during exercise. The potential difference between normal and CHF rats in exercise-induced changes in Controller and plant should be examined to fully understand the mechanism of exercise hyperpnea and to develop a method to attenuate this
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EMBC - Sensitized Central Controller of ventilation in rats with chronic heart failure contributes to hyperpnea little at rest but more during exercise.
2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006Co-Authors: Tadayoshi Miyamoto, Toru Kawada, Masashi Inagaki, Masaru Sugimachi, Hiroshi Takaki, Atsunori Kamiya, Toshiaki Shishido, Kenji SunagawaAbstract:BACKGROUND: To understand the pathophysiologic basis of exercise hyperpnea in chronic heart failure (CHF), we have developed an experimental method quantitatively characterizing ventilatory regulation system in rats. An equilibrium diagram illustrates the characteristics of two subsystems, i.e., the Central Controller (arterial CO2 tension [Pa(CO2)] to minute ventilation [V(E)] relationship) and peripheral plant (V(E) to Pa(CO2) relationship). In this study, we compared these between normal and CHF rats at rest. METHOD: In anesthetized 6 postinfarction CHF rats and 6 normal rats, we induced hypercapnia by changing inspiratory CO2 fraction and measured the steady-state Pa(CO2) to V(E) relation. We altered V(E) by varying the level of artificial ventilation and measured the V(E) to Pa(CO2) relation. RESULTS: Central Controller gain S was significantly lager in CHF rats, confirming clinical observation. The V(E) at rest (operating point) in CHF was 24% larger; Central hypersensitivity, however, contributed little (6%) to this increase. CONCLUSION: Central hypersensitivity alone would not explain hyperpnea at rest in CHF rats. Considering the right and upward shift of V(E) to Pa(CO2) relation, Central hypersensitivity contributes more to hyperpnea during exercise. The potential difference between normal and CHF rats in exercise-induced changes in Controller and plant should be examined to fully understand the mechanism of exercise hyperpnea and to develop a method to attenuate this.
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Integrated characterization of the human chemoreflex system controlling ventilation, using an equilibrium diagram.
European journal of applied physiology, 2004Co-Authors: Tadayoshi Miyamoto, Toru Kawada, Masashi Inagaki, Yusuke Yanagiya, Masaru Sugimachi, Hiroshi Takaki, Kenji SunagawaAbstract:The chemoreflex system controlling ventilation consists of two subsystems, i.e., the Central Controller (controlling element), and peripheral plant (controlled element). We developed an integral framework to quantitatively characterize individual ventilatory regulation by experimental determination of an equilibrium diagram using a modified metabolic hyperbola and the CO2 response curve. In 13 healthy males, the steady-state arterial CO2 pressure (PaCO2) and minute ventilation (V e ) were measured. To characterize the Central Controller, we changed fraction of inspired CO2 (0, 3.5, 5 and 6% CO2 in 80% oxygen with nitrogen balance) and measured the PaCO2–V e relation. To characterize the peripheral plant, we altered V e by hyper- or hypoventilation using a visual feedback method, which made it possible to control both tidal volume and breathing frequency, and measured the V e –PaCO2 relation. The intersection between the two relationship lines gives the operating point. The relationship between PaCO2 and V e for the Central Controller was reasonably linear in each subject (r2=0.808~0.995). The peripheral plant approximated a modified metabolic hyperbolic curve (r2=0.962~0.996). The operating points of the system estimated from the two relationship lines were in good agreement with those measured under the closed-loop condition. The gain of the Central Controller was 1.9 (1.0) l min−1 mmHg−1 and that of the peripheral plant was 3.0 (0.5) mmHg l−1 min−1. The total loop gain, the product of the two gains, was 5.3 (2.5). We conclude that human ventilatory regulation by the respiratory chemoreflex system can be quantitatively characterized using an equilibrium diagram. This framework should be useful for understanding the mechanisms responsible for abnormal ventilation under various pathophysiological conditions.
Dawn M Tilbury - One of the best experts on this subject based on the ideXlab platform.
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a software defined framework for the integrated management of smart manufacturing systems
Manufacturing letters, 2018Co-Authors: Felipe Lopez, Yuru Shao, Morley Z Mao, James Moyne, Kira Barton, Dawn M TilburyAbstract:Abstract This paper introduces software-defined control (SDC) as a framework that enables integrated and programmatic management of smart manufacturing systems. SDC consolidates information from the production and enterprise levels in a Central Controller that monitors performance and detects changing conditions. The integrated view of the system provided by the Central Controller supports the development of applications, which supply the Central Controller with new information and reconfiguration recommendations. SDC is designed to be scalable and compatible with current automation technologies. A simulation shows that the incorporation of plant-floor information in management decisions, as supported by SDC, has the potential to improve profitability.
A.j. Van Der Schaft - One of the best experts on this subject based on the ideXlab platform.
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Nonlinear systems which have finite-dimensional /spl Hscr//sub /spl infin// suboptimal Central Controllers
Proceedings of 32nd IEEE Conference on Decision and Control, 1Co-Authors: A.j. Van Der SchaftAbstract:Following the work of Basar and Bernhard (1990), the authors derived (1993) the nonlinear Central Controller solving the nonlinear (standard) H/sub /spl infin// suboptimal control problem. This nonlinear Central Controller is an infinite-dimensional system, and resembles very much the solution in nonlinear stochastic filtering or nonlinear deterministic filtering. After showing that in the linear case the nonlinear Central Controller reduces to the finite-dimensional Central Controller, we consider in the present note the question if there are truly nonlinear systems having finite-dimensional Central Controllers. Guided by similar considerations in nonlinear stochastic and deterministic filtering, we characterize a specific class of nonlinear systems having finite-dimensional Central Controllers. This class can be regarded as the deterministic H/sub /spl infin// analogue of the class of nonlinear systems admitting finite dimensional filters as identified by Benes (1981). >
