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1.
采用振动控制算法中的线性二次型最优控制,研究了在地震作用下的结构控制作用系统参数优化设计,即假定控制器数量、位置,对控制作用参数进行优化.将选取的主结构简化为多自由度模型,将MTMD(多重调谐质量阻尼器)对结构的反力与地震荷载共同作为结构的荷载输入分析;基于对主结构多模态耦合作用的考虑以及MTMD加载位置的初步假定,以二次型性能指标对系统状态方程加以控制.得到控制效果与利用最优参数法的结构控制效果做进一步比较验证.最后利用ANSYS优化设计模块,对已得到的控制器参数进行二次优化.  相似文献   

2.
结构地震反应的非全状态控制   总被引:4,自引:2,他引:4  
本文提出了地震下结构芳动控制的一种非全状态控制算法和控制器位置与算法参数统一优化的概念及其统一优化的方法,文中对某试验用模型结构,用红典线最优控制算法和本文提出的控制算法进行了主动控制仿真分析,同时用本文提出的统一优化方法对控制器位置和算法参数进行了优化,结果表明,本文提出的统一优化概念和方法合理可行,控制算法可以取得良好的控制效果。  相似文献   

3.
最优控制方法是利用极值原理、最优滤波或动态规划等最优化方法来求解结构振动最优控制输入的一种设计方法。最优控制规律均是建立在系统理想数学模型基础上,而实际结构控制中往往采用降阶模型且存在多种约束条件,因此基于最优控制理论设计的控制器大都只能实现次最优控制。迭代学习控制理论的产生与发展,为结构振动主动控制提供了新的方法,但迭代学习控制的应用又受到其控制效果与其收敛性的制约。本文基于线性二次型最优控制与迭代学习控制相结合的思想,提出二次型最优迭代学习混合控制方法(LQILC),以二次型性能指标为控制目标,提高迭代的收敛速度;在性能指标的基础上进行迭代学习,改善了二次型最优控制的控制效果。以Emerson Memorial斜拉桥Benchmark模型为研究对象,采用二次型迭代学习控制策略(LQILC)对该桥的地震响应进行有效的控制,并得出Benchmark指标评价其对该桥的控制效果。  相似文献   

4.
彭勇波  李杰 《地震学刊》2011,(5):483-489
本研究发展了结构地震反应性态的随机最优控制理论和方法。这一研究建立在物理随机系统思想的新理论框架下,突破了以I^to随机微分方程描述动力系统的经典随机最优控制的藩篱。提出了基于系统二阶统计量评价、单目标超越概率和多目标能量均衡的控制器参数设计准则,以及基于概率可控指标的控制器位置设计准则,并将它们统一为物理随机最优控制的广义最优控制律。数值算例分析表明,本文发展的物理随机最优控制方法能够实现结构地震反应性态的精细化控制。  相似文献   

5.
针对传统线性二次型最优控制(Linear quadratic optimal control,LQR)等主动控制方法存在鲁棒性较差的不足,考虑结构参数和外部激励的不确定性,提出一种控制算法简单、便于工程应用的鲁棒H∞最优控制方法.将工程中常用的二次型最优指标结合于鲁棒H∞控制系统的分析中,使得控制器的性能指标容易衡量;通过引入线性矩阵不等式(Linear Matrix Inequalities,LMI)减小求解的复杂度.以一个多层剪切型建筑结构模型为例进行了仿真,并与LQR方法进行对比,仿真结果初步表明该方法具有较好的控制效果和鲁棒性.  相似文献   

6.
可控制杆件在双层柱面网壳结构中的最优布置   总被引:5,自引:0,他引:5  
在分析网壳结构特点的基础上,提出了网壳结构中半主动控制器位置优化的两种准最优准则,研究了变刚度变阻尼可控制杆件在双层柱面网壳结构中最优布置规律。通过仿真分析,验证了准最优准则的有效性和最优位置规律的正确性。  相似文献   

7.
基于形状记忆合金(SMA)的超弹性特性和压电陶瓷(PZT)逆压电效应,设计了一种SMA-压电摩擦智能阻尼器。针对遗传算法局部搜索能力差,容易陷入早熟的缺陷,提出了一种改进的遗传算法,并以多模态控制性能指标作为优化准则,对一空间杆系结构的阻尼器布置进行了优化分析。采用线性二次型最优控制(LQR)算法,选取4个阻尼器,分析了未改进和改进后的两种最优布置方案对结构地震反应的控制效果。结果表明,改进后的遗传算法有更好的收敛性,更强的寻优能力,能使阻尼器得到更优的布置位置;改进的遗传算法得到的阻尼器优化布置方案可以更加有效地降低结构的地震峰值反应。  相似文献   

8.
针对固定增益变结构控制器应用于结构振动控制工程中可能引起控制系统过大的抖振,采用了一种基于RBF神经网络调节控制切换增益的变结构控制方法对地震作用下建筑结构的振动控制问题进行研究。根据二次型最优控制方法设计了切换面;基于切换面存在的可达性条件推导出控制律的表达式。以一个三层框架结构模型为例来验证所提变结构控制方法的有效性,算例分析结果表明,所提控制方法能够有效地减小结构的地震峰值响应,且达到了削弱控制系统抖振的目的。  相似文献   

9.
本文针对非线性结构振动控制问题,提出了一种将线性二次型最优(LQR)控制算法和模糊控制算法相结合的自适应减震控制方法。以原线性结构,即名义系统作为参考模型,基于参考模型设计了LQR控制器,并利用遗传算法优化LQR控制器的加权系数;将结构振动中的非线性部分作为不确定参数,以此来设计模糊控制器,弥补了结构非线性部分对振动控制的影响。最后,通过钢筋混凝土非线性结构算例验证本文所提算法的有效性。结果表明:强震作用下,结构构件会产生屈服进入非线性阶段,而基于线性参考模型设计的LQR控制器并不适用于非线性结构;模糊控制器可以补偿结构非线性产生的影响,达到自适应减震控制的目的。  相似文献   

10.
本文基于地震作用不确定性的椭球傅里叶界限凸模型,建立了建筑结构和控制系统的协同优化模型:以最小化结构质量和最大加速度响应加权和为目标函数,以结构截面的尺寸、阻尼器的数量和位置为设计变量,约束条件为结构的强度、刚度、整体及局部的稳定性。运用遗传算法来解决具有连续和离散两类设计变量的优化问题。算例结果表明结构与控制的协同化优化设计能使结构性能和控制效果同时达到最佳状态。  相似文献   

11.
An algorithm to calculate direct velocity feedback gain with limited number of sensors is developed in a simple way such that a certain performance index is minimized according to QN control method. If a limited number of velocity outputs can be measured, full velocity responses of the whole structure can be interpolated based on the mode shapes. By defining the performance index function as a combination of the structure's velocity responses and control forces only, feedback gain can be determined according to QN control method with the external excitation being taken into account throughout the entire algorithm. Control forces are then regulated by the time‐invariant feedback gain matrix. The effective location of the active control devices for a building structure subjected to intermediate‐storey excitation has been determined to be in the three floors adjacent to the vibration source. Hence for the purpose of this paper, only the optimal placement of sensors is verified. It is shown in this paper that if the dynamic behaviour of the structure is well described by a mathematical model, sufficient response reduction effect can be achieved according to the new DVFC algorithm, and the degradation of control performance due to time delay can also be verified. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

12.
磁流变阻尼器在受控结构中的优化布置   总被引:4,自引:0,他引:4  
高层建筑结构中由于地震引起的结构体系的振动是十分严重的,利用磁流变阻尼器进行振动控制的方法可以有效减小体系的振动反应、这种振动控制的效果,不仅取决于阻尼器出力大小和控制算法的优化,也取决于阻尼器在高层结构中的布置位置。首先对近年来出现的许多优化布置方法进行了阐述,论述了这些方法的优缺点,然后选用了一种优化布置方法并结合一个结构体系进行了阻尼器的优化布置研究,最后给出了阻尼器优化布置的几个原则。研究的结果表明通过阻尼器在高层结构中的优化布置可以有效提高振动控制的效果.  相似文献   

13.
This paper deals with the optimal design of yielding metallic dampers and friction dampers together as they both have similar design characteristics and parameters. Ample tests and analytical studies have confirmed the effectiveness of these energy dissipation devices for seismic response control and protection of building structures. Since these devices are strongly non‐linear with several parameters controlling their behaviour, their current design procedures are usually cumbersome and not optimal. In this paper, a methodology is presented to determine the optimal design parameters for the devices installed at different locations in a building for a desired performance objective. For a yielding metallic damper, the design parameters of interest are the device yield level, device stiffness, and brace stiffness. For a friction device, the parameters are the slip load level and brace stiffness. Since the devices and the structures installed with these devices behave in a highly non‐linearly manner, and thus must be evaluated by a step‐by‐step time history approach, the genetic algorithm is used to obtain the globally optimal solution. This optimal search approach allows an unusual flexibility in the choice of performance objectives. For demonstration purposes, several sets of numerical examples of optimal damper designs with different performance objectives are presented. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

14.
Estimation of lateral displacement and acceleration responses is essential to assess safety and serviceability of high-rise buildings under dynamic loadings including earthquake excitations. However, the measurement information from the limited number of sensors installed in a building structure is often insufficient for the complete structural performance assessment. An integrated multi-type sensor placement and response reconstruction method has thus been proposed by the authors to tackle this problem. To validate the feasibility and effectiveness of the proposed method, an experimental investigation using a cantilever beam with multi-type sensors is performed and reported in this paper. The experimental setup is first introduced. The finite element modelling and model updating of the cantilever beam are then performed. The optimal sensor placement for the best response reconstruction is determined by the proposed method based on the updated FE model of the beam. After the sensors are installed on the physical cantilever beam, a number of experiments are carried out. The responses at key locations are reconstructed and compared with the measured ones. The reconstructed responses achieve a good match with the measured ones, manifesting the feasibility and effectiveness of the proposed method. Besides, the proposed method is also examined for the cases of different excitations and unknown excitation, and the results prove the proposed method to be robust and effective. The superiority of the optimized sensor placement scheme is finally demonstrated through comparison with two other different sensor placement schemes: the accelerometer-only scheme and non-optimal sensor placement scheme. The proposed method can be applied to high-rise buildings for seismic performance assessment.  相似文献   

15.
The optimal design and placement of controllers at discrete locations is an important problem that will have impact on the control of civil engineering structures. Though algorithms exist for the placement of sensor/actuator systems on continuous structures, the placement of controllers on discrete civil structures is a very difficult problem. Because of the nature of civil structures, it is not possible to place sensors and actuators at any location in the structure. This usually creates a non‐linear constrained mixed integer problem that can be very difficult to solve. Using genetic algorithms in conjunction with gradient‐based optimization techniques will allow for the simultaneous placement and design of an effective structural control system. The introduction of algorithms based on genetic search procedures should increase the rate of convergence and thus reduce the computational time for solving the difficult control problem. The newly proposed method of simultaneously placing sensors/actuators will be compared to a commonly used method of sensors/actuators placement where sensors/actuators are placed sequentially. The savings in terms of energy requirements and cost will be discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

16.
大跨径钢管混凝土拱桥减震控制装置参数的研究   总被引:1,自引:0,他引:1  
大跨度桥梁结构的减震控制研究对于桥梁结构的抗震安全具有重要意义。本文以主跨368m的茅草街大桥为研究对象,基于ANSYS建立了该桥的三维有限元模型,并采用子空间迭代法分析了该桥的动力特性。在此基础上进行了大跨度钢管混凝土拱桥的地震响应及减震控制研究,重点进行了弹性连接装置和粘滞阻尼器减震效果的参数敏感性分析,并对比分析了不同位置布设减震装置时的效果。结果表明,纵飘振型对该桥肋纵向相对位移的贡献最大;弹性连接装置和阻尼器均能有效减小地震作用下该桥的肋梁纵向相对位移;综合考虑各关键部位的地震响应时,同时采用两类减震装置并将其分散布置时的减震效果最佳。结论可供大跨度中承式钢管混凝土系杆拱桥的抗震设计参考。  相似文献   

17.
针对巨-子结构隔震体系,在隔震层处或子结构顶部与主结构连接处,施加SMA-压电智能复合阻尼器,从而形成巨-子结构智能隔震体系。本文通过限界Hrovat最优控制算法设计了巨-子结构智能隔震体系的半主动控制器,在此基础上,对巨-子结构智能隔震体系进行了Simulink控制效果仿真分析,同时比较了控制装置安装位置的不同对结构控制效果的影响,并与普通隔震结构的减震效果进行了对比。研究结果表明,智能隔震控制1(隔震层加控制装置)和智能隔震控制2(子结构顶部加控制装置)2种控制方案在控制结构的位移方面效果相差不大。总体而言,智能隔震控制2对于控制子结构单元顶部的绝对加速度效果更为显著,但是相对于普通隔震而言,特别是在控制隔震层位移方面2种方案都具有较好的控制效果。实施智能控制可以有效改善巨-子结构被动控制体系的抗震性能,并能降低隔震结构在遭受强震时由于隔震层出现过大位移导致结构倾覆的危险。  相似文献   

18.
In order to investigate ways of reducing vibrations of building structures subjected to excitation acting on intermediate storey, active vibration controls are conducted with active control devices installed on different floors of the structure, and the effective location of control devices is also investigated. In this paper, we propose a new ‘Discrete‐Optimizing Control Method’ for vibration control. The control forces are determined analytically which makes the ‘discrete‐index function’ minimum. Through numerical simulation, the Discrete‐Optimizing Control Method is proved to be an effective control method. The response reduction effects are best when the control devices are concentrated on the adjacent three floors of the vibration source. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

19.
A damper device based on shape memory alloy (SMA) wires is developed for structural control implementation. The design procedures of the SMA damper are presented. As a case study, eight such SMA dampers are installed in a frame structure to verify the effectiveness of the damper devices. Experimental results show that vibration decay of the SMA damper controlled frame is much faster than that of the uncontrolled frame. The finite‐element method is adopted to conduct the free and forced vibration analysis of the controlled and uncontrolled frame. The experimental and numerical results illustrate that the developed SMA dampers are very effective in reducing structural response and have great potential for use as efficient energy dissipation devices with the advantages of good control of force and no lifetime limits, etc. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

20.
H_∞ drift control of time-delayed seismic structures   总被引:1,自引:1,他引:0  
In this paper,an optimal H∞ control algorithm was applied to the design of an active tendon system installed at the first story of a multi-story building to reduce its interstory drift due to earthquake excitations.To achieve optimal control performance and to guarantee the stability of the control system,an optimum strategy to select control parameters γ and α was developed.Analytical expressions of the upper and the lower bounds of γ and α were obtained for a single degree-of-freedom system with state fee...  相似文献   

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