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Active Control

The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform

Li Fu – 1st expert on this subject based on the ideXlab platform

  • Sliding Mode Semi-Active Control for High-Speed Pantograph
    Journal of Southwest Jiaotong University, 2020
    Co-Authors: Li Fu

    Abstract:

    In order to study the effects of Active and semi-Active technologies on pantograph performances,dynamic models for sliding mode Active and semi-Active Control of pantographs are established.Based on the models,dynamic performances of the high-speed pantograph-catenary system under passive Control,sliding mode Active Control,and sliding mode semi-Active Control are simulated using software Simulink.The influences of Active Control and semi-Active Control on the dynamic performances and current-receiving quality of the pantograph-catenary system are analyzed.The results show that the pantograph-catenary vibration can be suppressed effectively by the sliding mode Active or semi-Active Control strategies,with a vibration magnitude reduction of 10% to 20%.The pantograph semi-Active Control is characterized by low external energy demand,unconditional stability of the Control process,close effect to the Active Control,and will become an important method to improve the vibration performance of pantographs in high-speed conditions.

  • Research on Optimal Active Control of Railway Caternary
    Journal of Railway Engineering Society, 2020
    Co-Authors: Li Fu

    Abstract:

    Research purposes: In order to research the influence of the Active Control on the property of the railway catenary,the finite element model for the catenary is established,the whole quality of the model and the stiffness matrix data are calculated with Ansys software,the whole quality and whole stiffness matrix are resolved with KMExtract program.With these,the dynamics equation is established for the catenary.In order to simulate the system and design the Controller easily,the modal reduction order method is used to reduce the system order and transform it into the equation of state for designing the LQR Controller for the system,and the simulation analysis of the states of the catenary before and after taking the Active Control is made with siimulink. Research conclusions:The research shows:(1)Taking the Active Control of the catenary can improve its vibration property.The maximum and minimum vibration values of the catenary can be cut by above 90%,and the mean square deviation can be cut by 70%.Therefore,the system property is much improved.(2) The Active or semi-Active Control of the catenary becomes the important way to improve the catenary property when it is difficult to improve the catenary property by changing the catenary parameters.

J.m. Ko – 2nd expert on this subject based on the ideXlab platform

  • A bounded stochastic optimal semi-Active Control
    Journal of Sound and Vibration, 2020
    Co-Authors: Z.g. Ying, Y.q. Ni, J.m. Ko

    Abstract:

    A bounded stochastic optimal semi-Active Control strategy for magneto-rheological/electro-rheological (MR/ER) dampers is developed from the previously proposed strategy by considering the constraint of semi-Active Control forces. The Control force is separated into a semi-Active part and passive part incorporated in the unControlled system. The Control system is converted into an averaged Control system for energy processes by using the stochastic averaging method. The bounded and dynamic constraint of semi-Active Control forces and a performance index are formulated to constitute a bounded stochastic optimal semi-Active Control problem. Then the dynamical programming equation is established by applying the stochastic dynamical programming principle to the Control problem. The bounded optimal semi-Active Control forces are obtained from solving this equation based on the variation method. A bounded optimal Active Control law given is implementable by MR/ER dampers. Finally, an example of Controlled and stochastically excited nonlinear system is studied to illustrate the efficiency and chattering attenuation of the developed bounded Control.Department of Civil and Environmental Engineerin

  • A bounded stochastic optimal semi-Active Control
    Journal of Sound and Vibration, 2007
    Co-Authors: Z.g. Ying, Y.q. Ni, J.m. Ko

    Abstract:

    A bounded stochastic optimal semi-Active Control strategy for magneto-rheological/electro-rheological (MR/ER) dampers is developed from the previously proposed strategy by considering the constraint of semi-Active Control forces. The Control force is separated into a semi-Active part and passive part incorporated in the unControlled system. The Control system is converted into an averaged Control system for energy processes by using the stochastic averaging method. The bounded and dynamic constraint of semi-Active Control forces and a performance index are formulated to constitute a bounded stochastic optimal semi-Active Control problem. Then the dynamical programming equation is established by applying the stochastic dynamical programming principle to the Control problem. The bounded optimal semi-Active Control forces are obtained from solving this equation based on the variation method. A bounded optimal Active Control law given is implementable by MR/ER dampers. Finally, an example of Controlled and stochastically excited nonlinear system is studied to illustrate the efficiency and chattering attenuation of the developed bounded Control.

Katsuaki Sunakoda – 3rd expert on this subject based on the ideXlab platform

  • 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, 2017
    Co-Authors: Kazuhiko Hiramoto, Taichi Matsuoka, Katsuaki Sunakoda

    Abstract:

    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.

  • Semi-Active Control of Structural Systems Aiming to Approximate the Performance of the Targeted Active Control Law: Output Emulation Approach
    Volume 8: Seismic Engineering, 2013
    Co-Authors: Kazuhiko Hiramoto, Taichi Matsuoka, Katsuaki Sunakoda

    Abstract:

    As a method for semi-Active Control of structural systems, the ActiveControl-based method that emulates the Control force of a targeted Active Control law by semi-Active Control devices has been studied. In the ActiveControl-based method, the semi-Active Control devices are not necessarily able to generate the targeted Active Control force because of the dissipative nature of those devices. In such a situation, the meaning of the targeted Active Control law becomes unclear in the sense of the Control performance achieved by the resulting semi-Active Control system. In this study, a new semi-Active Control strategy that approximates the Control output (not the Control force) of the targeted Active Control is proposed. The variable parameter of the semi-Active Control device is selected at every time instant so that the predicted Control output of the semi-Active Control system becomes close to the corresponding predicted Control output of the targeted Active Control as much as possible. Parameters of the targeted Active Control law are optimized in the premise of the above “output emulation” strategy so that the Control performance of the semi-Active Control becomes good and the “error” of the achieved Control performance between the targeted Active Control and the semi-Active Control becomes small.Copyright © 2013 by ASME

  • Simultaneous optimal design of the structural model for the semi‐Active Control design and the model‐based semi‐Active Control
    Structural Control & Health Monitoring, 2013
    Co-Authors: Kazuhiko Hiramoto, Taichi Matsuoka, Katsuaki Sunakoda

    Abstract:

    SUMMARY

    Various semi-Active Control methods have been proposed for vibration Control of civil structures. In contrast to Active vibration Control systems, all semi-Active Control systems are essentially asymptotically stable because of the stability of general structural systems with structural damping and the energy dissipative nature of the semi-Active Control itself. In this study, by utilizing the aforementioned property on the stability of semi-Active Control systems, a structural model for the semi-Active Control design and a model-based semi-Active Control law are simultaneously designed so that the Control performance of the resulting semi-Active Control system becomes good. The model for the Control system design is assumed to be a linear parameter varying model with adjustable structural design parameters. The semi-Active Control law is based on the one step ahead prediction of the structural response of the designed model for the Control system design. A genetic algorithm is adopted to obtain design parameters in the model for the Control system design and the semi-Active Control law. Those design parameters are optimized so that the closed-loop system with the detailed dynamic model that accurately approximates the dynamic behavior of the real structural system and the semi-Active Control law obtained with the model for the Control system design. The effectiveness of the present approach is shown with a simulation study. Copyright © 2013 John Wiley & Sons, Ltd.