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。

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.

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。

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。

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。

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.

悬浮电容H桥级联七电平逆变器的混合载波频率调制策略

多电平逆变器具有输出电压谐波含量少、开关器件电压应力低、等效开关频率高等优点,广泛应用于新能源发电场合。悬浮电容H桥级联七电平逆变器,因开关频率低、器件数量少、输出电平数量多得到广泛的关注。为了降低损耗,使H桥逆变单元开关管以低开关频率动作,悬浮电容逆变单元开关管以高开关频率动作,但是会引起过调制和悬浮电容电压失控的问题。为解决过调制问题,该文提出基于调制波分解的混合载波频率调制策略,增加过调制区间的调制过程,分解悬浮电容逆变单元超出载波部分的调制波,使H桥逆变单元开关管以低开关频率运行;同时提出基于工作模式切换的有功功率分解控制,详细分析两种工作模式下的稳压控制原理,根据电容电压的状态改变悬浮电容逆变单元有功功率大小,实现不同工况下悬浮电容电压均衡。最后通过仿真和实验验证了所提调制策略的正确性。

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.

建筑结构振动主动控制的H_2/H_∞混合凸优化方案

在地震信号和建筑结构系统的范数分析基础上,使用了混合控制优化指标J作为优化目标,并给出其物理含义·针对H2控制方案和H∞控制方案的优缺点,通过LMI凸优化方法求解混合控制器,给出了在给定γ值的前提下极小化指标J的H2/H∞混合控制方案,并给出了仿真算例·

2-D状态滞后系统的时滞相关H_∞控制

研究了具有状态滞后的二维(2-D)离散线性系统的时滞相关H∞控制问题.首先提出了2-D状态滞后系统的时滞相关有界实引理;基于此引理,通过线性矩阵不等式(LMI)的可行性,设计状态反馈控制器使得闭环系统具有H∞扰动衰减度γ;进而求解一个线性凸优化问题可得最小化γ值.所得的时滞相关结果可转化为时滞无关情形.数值算例说明了所得结论的有效性和优越性.

巡航导弹成像器稳定装置H_2/H_∞混合最优PID控制器设计

本文针对某巡航导弹成像器稳定装置同时在鲁棒稳定性和系统性能有着很高要求的特点 ,采用H2 /H∞ 混合优化的设计方法设计了H2 /H∞ 混合最优PID控制器。仿真和实验结果表明采用该设计方法设计的巡航导弹成像器稳定装置满足性能要求 ,而且比采用H∞

结构振动的H_2/H_∞混合最优控制

讨论了柔性结构振动的混合Ｈ２／Ｈ∞最优控制问题、结构振动控制器的鲁棒稳定性转化为Ｈ∞最优控制问题，以及振动控制的最优二次性能转化为Ｈ２最优控制问题，并提出了利用遗传算法求解Ｈ２／Ｈ∞的方法。通过结构振动主动控制的计算机仿真，表明用遗传优化算法解Ｈ２／Ｈ∞最优控制是有效的。仿真结果还表明，Ｈ２和Ｈ∞性能指标是相互矛盾的，本方法能有效地处理Ｈ２和Ｈ∞性能指标的折衷问题，以得到闭环系统的鲁棒稳定性和良好的时域性能。

固定结构混合H_2/H_∞控制器参数的全局优化

首先运用增广 Hermite- Biehler定理 ,解析地给出使任意给定 (稳定或不稳定 )被控对象闭环稳定的控制器参数取值域 .然后 ,在该参数取值域内运用遗传优化算法得到了满足指定混合 H2 / H∞ 性能指标的 Pareto最优控制器参数值 .仿真例子验证了该方法的有效性 .

2-D奇异系统Roesser模型的鲁棒H_∞控制

考虑具有参数不确定性的2-D奇异系统Roesser模型(简称2-D SRM)鲁棒H∞控制问题．在给出界实引理的另一等价形式的基础上,通过求解矩阵不等式,给出了不确定2-D奇异系统鲁棒H∞控制问题可解的充分条件及静态状态反馈控制律设计的代数表达式．最后通过一个仿真算例验证了方法的有效性．

一类非线性微分代数系统的L_2-增益分析及状态反馈H_∞控制

分析了一类非线性微分 代数系统的 L2 增益 ,并讨论了一类状态反馈H∞ 控制问题 .在一定条件下给出了控制器的设计 ,并保证了闭环指数为 1且零解渐近稳定 .

参考模型前馈2-DOF指令跟踪H_∞控制器设计研究

结合二自由度控制和参考模型控制系统设计原理,提出了一种参考模型前馈控制的二自由度控制系统设计结构。通过推导给出了标准H∞控制广义被控对象的状态空间方程实现形式,并运用该理论研究了导弹俯仰通道指令跟踪系统鲁棒H∞控制器设计问题。文中采用LMI凸优化进行二自由度鲁棒H∞控制器设计,简化了传统方法设计控制器的求解过程。仿真结果表明,应用该方法设计的闭环系统具有良好的快速跟踪特性,说明了该方法的正确性和有效性。