Hybrid Electromagnetic Shunt Damper for Vibration Control

Abstract It has been shown that shunting electromagnetic devices with electrical networks can be used to damp vibrations. These absorbers have however limitations that restrict the control performance, i.e., the total damping of the system and robustness versus parameter variations. On the other hand, the electromagnetic devices are widely used in active control techniques as an actuator. The major difficulty that arises in practical implementation of these techniques is the power consumption required for conditioners and control units. In this study, robust hybrid control system is designed to combine the passive electromagnetic shunt damper with an active control in order to improve the performance with low power consumption. Two different active control laws, based on an active voltage source and an active current source, are proposed and compared. The control law of the active voltage source is the direct velocity feedback. However, the control law of the active current source is a revisited direct velocity feedback. The method of maximum damping, i.e., maximizing the exponential time-decay rate of the response subjected to the external impulse forcing function, is employed to optimize the parameters of the passive and the hybrid control systems. The advantage of using the hybrid control configuration in comparison with purely active control system is also investigated in terms of the power consumption. Besides these assets, it is demonstrated that the hybrid control system can tolerate a much higher level of uncertainty than the purely passive control systems.

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Active/Passive Hybrid Control System for Compressor Surge Based on Fuzzy Logic

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4026953 ◽

2014 ◽

Vol 136 (9) ◽

Cited By ~ 10

Author(s):

Hanlin Sheng ◽

Wei Huang ◽

Tianhong Zhang ◽

Xianghua Huang

Keyword(s):

Fuzzy Logic ◽

Control System ◽

Active Control ◽

Hybrid System ◽

Passive Control ◽

Hybrid Control ◽

Control Mode ◽

Compressor Surge ◽

Surge Line ◽

Hybrid Control System

A hybrid control system has been proposed for compressor surge, which combines the active method with the passive method. A bleed valve was selected as the actuator in the proposed system. As a submode of the hybrid system, a fuzzy logic based active controller was designed to extend the stability operating range of the compressor. Meanwhile, a surge avoidance controller was used as a backup-mode to improve the safety performance of the system. The simulation results showed that the compressor can operate steadily outside the surge line under active control mode and can be dragged back to inside the surge line by the passive control mode when the alternative fails. One advantage of the proposed control system is that it does not need a model of the compressor, and it works on any compression system. Passive surge control is a reliable and widely applied method in industrial compressors. The hybrid system makes the active control approach closer to the industrial implementation.

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Analysis of Vibration Control due to Strong Earthquakes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.4179 ◽

2010 ◽

Vol 163-167 ◽

pp. 4179-4184 ◽

Cited By ~ 1

Author(s):

He Len Wu

Keyword(s):

Control System ◽

Active Control ◽

Base Isolation ◽

Hybrid Control ◽

Ground Motions ◽

Isolation System ◽

System A ◽

Base Isolation System ◽

Active Control System ◽

Hybrid Control System

The paper proposes an aseismic hybrid control system to control the response of structures subjected to large ground motions caused by large magnitude earthquakes. The proposed hybrid control system consists of a base isolation system (laminated rubber bearings) connected to an active control system (a tuned mass damper and an actuator). The base isolation system is used to decouple the horizontal ground motions from the structure, whereas the active control system is used to protect the safety and integrity of the base isolation system. A 5-story benchmark building model is developed to study the effectiveness of the hybrid control system against different ground motions. It was found from the numerical results that rubber bearing system alone shows good performance and resists ground motion due to Hachinohe 1968, Kobe 1995, and Northridge 1994 earthquakes, but is somewhat unable to protect the model against El-Centro 1940 earthquake. After the installation of an active control system onto the rubber-isolated model, further improvements to earthquake resistance against these four earthquakes were observed, especially against the El-Centro earthquake. The merit of the hybrid control system lies in its capability to protect against different ground motions, with varying intensity and frequency content.

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Control Algorithms for Semi-Active Structural Systems: Do they Really Matter?

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.56.182 ◽

2008 ◽

Vol 56 ◽

pp. 182-187

Author(s):

Antonio Occhiuzzi

Keyword(s):

Control System ◽

Control Systems ◽

Active Control ◽

Structural Control ◽

Control Algorithm ◽

Scientific Literature ◽

Control Algorithms ◽

Control Law ◽

Structural Systems ◽

Active Structural Control

Control algorithms for semi-active structural control system found in the scientific literature often rely on the choice of several parameters included in the control law. The present paper shows the preliminary conclusions of a study aiming to explain the weak dependency of the response reduction associated to semi-active control systems on the particular choice of the control algorithm adopted, provided that the relevant parameters of any control law be properly tuned.

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Hybrid Control System for Seismic Protection of the Benchmark Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.193-194.801 ◽

2012 ◽

Vol 193-194 ◽

pp. 801-804

Author(s):

Jian Fang Fu ◽

Xin Jian Feng ◽

Jian Lin Zhang

Keyword(s):

Genetic Algorithm ◽

Control System ◽

Control Systems ◽

Hybrid Control ◽

Seismic Protection ◽

Control Parameters ◽

Objective Functions ◽

Benchmark Model ◽

Damper Control ◽

Hybrid Control System

In this paper, a 20-storey Benchmark model is used to compare the effects of various control systems, including Damper control system, TMD control system and Hybrid control system. In the course of the optimization, the displacement reducing coefficient (DRF) and the storey drift reducing coefficient (SDRF) are used as the objective functions to optimize the control parameters based on Genetic Algorithm (GA). Numerical results prove the advisability of the Hybrid control system of dampers and TMD, which can not only decrease the floor displacement, but also improve the mutation of the storey drift.

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Design Method of Semi-Active Control Systems Minimizing the Error Between the Controlled Signals of the Semi-Active and its Reference Active Control Systems

Volume 8: Seismic Engineering ◽

10.1115/pvp2017-65707 ◽

2017 ◽

Author(s):

Kazuhiko Hiramoto ◽

Taichi Matsuoka ◽

Katsuaki Sunakoda

Keyword(s):

Control System ◽

Vibration Control ◽

Control Systems ◽

Active Control ◽

Output Signal ◽

Error Function ◽

Quadratic Function ◽

Control Law ◽

Lyapunov Matrix ◽

Active Control System

We propose a semi-active vibration control method of structural systems based on the output emulation approach. In the output emulation approach, the semi-active control law is obtained so that the controlled output signal of the semi-active control system is similar to that of the reference active control system. The reference active control system is a virtual control system employing the actuator for vibration control and achieves the ideal control performance. Because the constraints of the semi-active control comes from the inherent dissipative characteristics of semi-active control devices a certain amount of the error of the controlled output signals between the semi-active and its reference active control system is unavoidable. To realize the semi-active control system based on the output emulation approach, i.e., the semi-active control system whose controlled output signal is similar to that of the reference active control system, the semi-active control law in the present study is obtained for minimizing an error function related to the controlled output. The error function is defined as a quadratic function on the output signal of the error between the semi-active and its reference active control systems and the Lyapunov matrix. The control characteristics of the reference active control law and free parameters in the Lyapunov matrix are searched with a boot-strap optimization algorithm for the optimal semi-active control system. Some simulation results are shown to claim the effectiveness.

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Effect of Response Related Weighting Matrices on Performance of Active Control Systems for Nonlinear Frames

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455417500304 ◽

2017 ◽

Vol 17 (03) ◽

pp. 1750030

Author(s):

Mohtasham Mohebbi ◽

Abdolreza Joghataie ◽

Hamed Rasouli Dabbagh

Keyword(s):

Control System ◽

Control Systems ◽

Active Control ◽

Structural Response ◽

Control Law ◽

Control Force ◽

Online Measurements ◽

Active Control System ◽

Distributed Genetic Algorithm ◽

Response Feedback

In this paper, the effect of various arrangements of displacement, velocity and acceleration related weighting matrices on the performance of active control systems on nonlinear frames has been studied. Different arrangements of weighting matrices and feedback combinations of the response have been considered to design the active controllers using a single actuator for reducing the response of an eight-storey bilinear hysteretic frame under white noise excitations. The nonlinear Newmark-based instantaneous optimal control algorithm has been used, where the distributed genetic algorithm (DGA) is employed to determine the proper set of weighting matrices. For each set of feedback and weighting matrices, the active control system has been designed with the optimal weights determined. Here, the objective is to minimize the maximum control force required to reduce the maximum structural drift to a value below the desired level. The numerical results of simulation show that, for the cases studied, the use of different arrangements of weighting matrices in the proposed method for the performance index of the active control law has no significant impact on the performance of the active control system. However, the type of response feedback combination included in the control law considerably affects the performance, and the controllers designed based on velocity feedback have been found to be more effective. It was also shown that for all the weight-cases, using the full feedback of response can lead to design controllers that require minimum control force to reduce the structural response with more online measurements. The robustness of the designed controllers for different weighting matrices arrangements and feedback combinations has also been tested under a number of real earthquake excitations with the results discussed.

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