Parameters Optimization and Performance Evaluation of the Tuned Inerter Damper for the Seismic Protection of Adjacent Building Structures

In order to improve the seismic performance of adjacent buildings,two types of tuned inerter damper(TID)damping systems for adjacent buildings are proposed,which are composed of springs,inerter devices and dampers in serial or in parallel.The dynamic equations of TID adjacent building damping systems were derived,and the H2 norm criterion was used to optimize and adjust them,so that the system had the optimum damping performance under white noise random excitation.Taking TID frequency ratio and damping ratio as optimization parameters,the optimum analytical solutions of the displacement frequency response of the undamped structure under white noise excitation were obtained.The results showed that compared with the classic TMD,TID could obtain a better damping effect in the adjacent buildings.Comparing the TIDs composed of serial or parallel,it was found that the parallel TIDs had more significant advantages in controlling the peak displacement frequency response,while the H2 norm of the displacement frequency response of the damping system under the coupling of serial TID was smaller.Taking the adjacent building composed of two ten-story frame structures as an example,the displacement and energy collection time history analysis of the adjacent building coupled with the optimum design parameter TIDs were carried out.It was found that TID had a better damping effect in the full-time range compared with the classic TMD.This paper also studied the potential power of TID in adjacent buildings,which can be converted into available power resources during earthquakes.

Robust Optimal H∞ Control for Uncertain 2-D Discrete State-Delayed Systems Described by the General Model

This paper investigates the problem of robust optimal H∞ control for uncertain two-dimensional (2-D) discrete state-delayed systems described by the general model (GM) with norm-bounded uncertainties. A sufficient condition for the existence of g-suboptimal robust H∞ state feedback controllers is established, based on linear matrix inequality (LMI) approach. Moreover, a convex optimization problem is developed to design a robust optimal state feedback controller which minimizes the H∞ noise attenuation level of the resulting closed-loop system. Finally, two illustrative examples are given to demonstrate the effectiveness of the proposed method.

ASUBOPTIMAL DESIGN OF H∞DECENTRALIZED STATE FEEDBACK CONTROL FOR INTERCONNEC TED SYSTEMS

In the paper, the problem of H∞ decentralized state feedback control for largescale systems is described. An algorithm is proposed which uses the method of a feasible direction matrix. The algorithm only requires the solution of an algebraic Riccati equation (ARE) and makes the H∞norm of the closedloop transfer function matrix from disturbance inputs to controlled outputs less than a given constant which ensure the stability of the overall controlled system at each iteration. The given example shows that the convergence of the algorithm is satisfactory.

A new semi-active suspension control strategy through mixed H_2/H_∞ robust technique

A new semi-active suspension control strategy through mixed H2/H∞ robust technique was developed due to its flexibility and robustness to model uncertainties.A full car model with seven degrees of freedom was established to demonstrate the effectiveness of the new control approach.Magneto-rheological(MR) dampers were designed,manufactured and characterized as available semi-active actuators in the developed semi-active suspension system.The four independent mixed H2/H∞ controllers were devised in order to perform a distributed semi-active control system in the vehicle by which the response velocity and reliability can be improved significantly.The performance of the proposed new approach was investigated in time and frequency domains.A good balance between vehicle's comfort and road holding was achieved.An effective and practical control strategy for semi-active suspension system was thus obtained.This new approach exhibits some advantages in implementation,performance flexibility and robustness compared to existing methods.

Mixed H_2/H_∞ State Feedback Attitude Control of Microsatellite Based on Extended LMI Method

For the appearance of the additive perturbation of controller gain when the controller parameter has minute adjustment at the initial running stage of system,to avoid the adverse effects,this paper investigates the mixed H_2/H_∞ state feedback attitude control problem of microsatellite based on extended LMI method.Firstly,the microsatellite attitude control system is established and transformed into corresponding state space form.Then,without the equivalence restriction of the two Lyapunov variables of H_2 and H∞performance,this paper introduces additional variables to design the mixed H_2/H_∞ control method based on LMI which can also reduce the conservatives.Finally,numerical simulations are analyzed to show that the proposed method can make the satellite stable within 20 s whether there is additive perturbation of the controller gain or not.The comparative analysis of the simulation results between extended LMI method and traditional LMI method also demonstrates the effectiveness and feasibility of the proposed method in this paper.

H_∞ Control for 2-D Discrete State Delayed Systems in the Second FM Model

这份报纸涉及 H 控制的问题为二维(2-D ) 分离州的延期系统由第二 Fornasini 和 Marchesini (FM ) 描述了州空间当模特儿。为这个 2-D 系统有 H 噪音变细的一个足够的条件以某个线性矩阵不平等(LMI ) 被给。最佳的 H 控制器被解决一个凸的优化问题获得。最后，一个模拟例子被给说明建议结果的有效性。

A New Design of Robust H∞Load-Frequency Controller for Optimal Coordination of Energy Generation in Power System Stability Using LMI Approach

This paper presents the problem of robust H∞?load frequency controller design and robust H￥ based approach called advanced frequency control (AFC). The objective is to split the task of balancing frequency deviations introduced by renewable energy source (RES) and load variations according to the capabilities of storage and generators. The problem we address is to design an output feedback controller such that, all admissible parameter uncertainties, the closed-loop system satisfies not only the prespecified H∞? norm constraint on the transfer function from the disturbance input to the system output. The conventional generators mainly balance the low-frequency components and load variations while the energy storage devices compensate the high- frequency components. In order to enable the controller design for storage devices located at buses with no generators, a model for the frequency at such a bus is developed. Then, AEC controllers are synthesized through decentralized static output feedback to reduce the complexity. The conditions for the existence of desired controllers are derived in terms of a linear matrix inequality (LMI) algorithm is improved. From the simulation results, the system responses with the proposed controller are the best transient responses.

LMI Approach to Robust H_∞/H_2 Controller Design with Regional Poles Constraint of a Pump-Motor System

The time domain guideposts requirements of a pump-motor system is transfered into a series of constraints which express the robust performance upper bound and regional poles limits of the closed loop system. Then the servo system control problem is transferred into the problem of robust performance optimizing under regional poles constrains described by linear matrix inequality （LMI）. These LMIs are easy to solve through the Matlab LMI-toolbox. Simulations indicate that the controller has excellent dynamic, static and disturbance rejection performance, and the control system is robust and has perfect H2 performance to the bounded external torque disturbance.

Optimal activated carbon for separation of CO_2 from(H_2 + CO_2) gas mixture

Seven types of activated carbon were used to investigate the effect of their structure on separation of CO2 from（H2 ＋ CO2） gas mixture by the adsorption method at ambient temperature and higher pressures. The results showed that the limiting factors for separation of CO2 from 53.6 mol% H2 ＋ 46.4 mol% CO2 mixture and from 85.1 mol% H2 ＋ 14.9 mol% CO2 mixture were different at 20 °C and about 2 MPa. The best separation result could be achieved when the pore diameter of the activated carbon ranged from 0.77 to 1.20 nm, and the median particle size was about2.07 lm for 53.6 mol% H2 ＋ 46.4 mol% CO2 mixture and 1.41 lm for 85.1 mol% H2 ＋ 14.9 mol% CO2 mixture. The effect of specific area and pore diameter of activated carbon on separation CO2 from 53.6 mol% H2 ＋ 46.4 mol% CO2 mixture was more significant than that from 85.1 mol% H2 ＋ 14.9 mol% CO2 mixture. CO2 in the gas phase can be decreased from 46.4 mol% to 2.3 mol%–4.3 mol% with a two-stage separation process.

Mathematical Analysis of Nipah Virus Infections Using Optimal Control Theory

The optimal use of intervention strategies to mitigate the spread of Nipah Virus (NiV) using optimal control technique is studied in this paper. First of all we formulate a dynamic model of NiV infections with variable size population and two control strategies where creating awareness and treatment are considered as controls. We intend to find the optimal combination of these two control strategies that will minimize the cost of the two control measures and as a result the number of infectious individuals will decrease. We establish the existence for the optimal controls and Pontryagin’s maximum principle is used to characterize the optimal controls. The numerical simulation suggests that optimal control technique is much more effective to minimize the infected individuals and the corresponding cost of the two controls. It is also monitored that in the case of high contact rate, controls have to work for longer period of time to get the desired result. Numerical simulation reveals that the spread of Nipah virus can be controlled effectively if we apply control strategy at early stage.

汽车四轮转向系统的H_2/H_∞混合控制

为使汽车四轮转向系统具有良好的鲁棒性和干扰抑制性能 ,针对外界干扰 ,对汽车四轮转向系统模型进行了分析 ,并将其转化为H2 /H∞ 控制问题 ,运用Matlab的LMI控制工具箱设计了H2 /H∞ 混合最优控制器。仿真结果表明 ,设计的最优控制器具有良好控制效果。

汽车主动悬架多目标H_2/H_∞混合控制

基于汽车四自由度半车模型设计主动悬架控制系统多目标优化控制律。采用高阶未建模扰动到控制输入传递函数的 H∞ 范数作为鲁棒性能评价指标 ,路面扰动到输出评价信号传递函数的 H2 范数作为 L QG性能评价指标 ,选取加权函数阵对悬架的频域性能指标进行整定 ,设计了多通道多目标优化 H2 /H∞ 混合控制器。仿真结果表明 ,多目标 H2 /H∞ 混合控制方案在保证系统具有未建模鲁棒稳定性的前提下 ,可使汽车获得较好的操纵稳定性和行驶平顺性。

H_2和H_∞主动悬架统一的理论框架与比较

以 2自由度 1/ 4车模型为例在鲁棒控制理论的统一框架下讨论H2 和H∞ 主动悬架的设计 ,并采用结构奇异值法和加权最坏RMS增益法对其鲁棒性能进行分析和比较。

混合H_2/H_∞鲁棒控制在飞行控制中的应用

利用混合 H2 / H∞ 鲁棒控制技术 ,研究飞机纵向控制系统的综合问题。针对飞机控制系统含有大量的非线性和不确定因素 ,用混合 H2 / H∞ 鲁棒控制方法设计线性状态反馈控制器 ,使飞机控制系统在鲁棒稳定条件下 ,满足一定的性能指标。在国产某飞机纵向控制系统中的应用表明 ,所提出的方法是实用的和有效的。

Designing mixed <i>H</i>₂/<i>H</i>_&infin;structure specified controllers using Particle Swarm Optimization (PSO) algorithm

This paper proposes an efficient method for designing accurate structure-specified mixed H2/H∞ optimal controllers for systems with uncertainties and disturbance using particle swarm (PSO) algorithm. It is designed to find a suitable controller that minimizes the performance index of error signal subject to an unequal constraint on the norm of the closed-loop system. Although the mixed H2/H∞ for the output feedback approach control is considered as a robust and optimal control technique, the design process normally comes up with a complex and non-convex optimization problem, which is difficult to solve by the conventional optimization methods. The PSO can efficiently solve design problems of multi-input-multi-output (MIMO) optimal control systems, which is very suitable for practical engineering designs. It is used to search for parameters of a structure-specified controller, which satisfies mixed performance index. The simulation and experimental results show high feasibility, robustness and practical value compared with the conventional proportional-integral-derivative (PID) and proportional-Integral (PI) controller, and the proposed algorithm is also more efficient compared with the genetic algorithm (GA).

基于LMI的广义系统混合H_2/H_∞优化控制

研究了广义线性系统的混合 H2 / H∞ 状态反馈优化控制问题。设计一个混合 H2 / H∞ 状态反馈控制器 ,在满足闭环系统的容许性及 H∞ 范数界的同时使得 H2 范数极小。利用线性矩阵不等式 ( L MI)方法得到该控制器存在的一个充分条件 ,并且给出闭环系统 H2

A MAXIMUM PRINCIPLE APPROACH TO STOCHASTIC H_2/H_∞ CONTROL WITH RANDOM JUMPS

A necessary maximum principle is given for nonzero-sum stochastic Oltterential games with random jumps. The result is applied to solve the H2/H∞ control problem of stochastic systems with random jumps. A necessary and sufficient condition for the existence of a unique solution to the H2/H∞ control problem is derived. The resulting solution is given by the solution of an uncontrolled forward backward stochastic differential equation with random jumps.

基于LMI的结构振动多目标鲁棒H_2/H_∞控制

研究了考虑建筑结构动力特性具有不确定性的多目标鲁棒H2/H∞控制问题。在设计控制器的过程中,将模型参数(包括质量、刚度和阻尼)的不确定性引入到状态方程的摄动矩阵之中,使得闭环系统对所有允许的不确定性同时满足H∞干扰抑制和最优H2性能。基于线性矩阵不等式优化技术,推导得到了线性矩阵不等式组来求解相应的多目标优化问题,应用MATLAB的线性矩阵不等式工具箱设计了输出反馈控制器。最后对一3层结构进行了振动控制仿真分析,结果表明了所提方法的有效性和优越性。

H_2/H_∞混合优化问题综述

H2 /H∞ 混合优化设计方法由于其可以使系统同时获得较好的鲁棒稳定性和鲁棒性能 ,一经提出 ,立即受到研究者的广泛关注 .本文综述了 H2 /H∞ 混合优化方法的产生、发展及其特点 ,概要介绍了 H2 /H∞ 优化理论研究的最新进展及实践应用的主要结果 ,分析了 H2 /H∞ 混合优化理论在理论和实际应用中的发展方向 .

Robust H_∞ and H_2 Static Output Feedback Control of Discrete-time Piecewise Affine Singular Systems with Norm-bounded Uncertainties

This paper is concerned with the problem of designing robust H∞and H2static output feedback controllers for a class of discrete-time piecewise-affine singular systems with norm-bounded time-varying parameters uncertainties. Based on a piecewise singular Lyapunov function combined with S-procedure,Projection lemma and some matrix inequality convexifying techniques,sufficient conditions in terms of linear matrix inequalities are given for the existence of an output-feedback controller for the discrete-time piecewiseaffine singular systems with a prescribed H∞disturbance attenuation level,and the H2norm is smaller than a given positive number. It is shown that the controller gains can be obtained by solving a family of LMIs parameterized by one or two scalar variables. The numerical examples are given to illustrate the effectiveness of the proposed design methods.