Observer based projective reduced-order synchronization of different chaotic systems

The projective reduced-order synchronization of two different chaotic systems with different orders is investigated based on the observer design in this paper.According to the observer theory,the reduced-order observer is designed.The projective synchronization can be realized by choosing the transition matrix of the observer as a diagonal matrix.Further,the synchronization between hyperchaotic Chen system(fourth order)and Rssler system(third order)is taken as the example to demonstrate the effectiveness of the proposed observer.Numerical simulations confirm the effectiveness of the method.

Nonlinear Control of an Induction Motor Using a Reduced-Order Extended Sliding Mode Observer for Rotor Flux and Speed Sensorless Estimation

This article proposes an innovative strategy to the problem of non-linear estimation of states for electrical machine systems. This method allows the estimation of variables that are difficult to access or that are simply impossible to measure. Thus, as compared with a full-order sliding mode observer, in order to reduce the execution time of the estimation, a reduced-order discrete-time Extended sliding mode observer is proposed for on-line estimation of rotor flux, speed and rotor resistance in an induction motor using a robust feedback linearization control. Simulations results on Matlab-Simulink environment for a 1.8 kW induction motor are presented to prove the effectiveness and high robustness of the proposed nonlinear control and observer against modeling uncertainty and measurement noise.

The Design of Reduced-order Observer for Systems with Monotone Nonlinearities

与单调非线性为系统关于存在和完整顺序的观察员的设计方法基于讨论，一个还原剂顺序观察员设计方法在线性矩阵不平等(LMI ) 有的假设下面被开发积极明确的矩阵答案和还原剂顺序观察员获得矩阵被 LMI 的解决方案计算。由线性转变，不包含系统产量的衍生物的信息的一个还原剂顺序观察员被提供。一个模型被模仿，一些结论基于还原剂顺序观察员的结果的比较被得出到完整顺序的观察员的。模拟证明这份报纸开发的设计方法有好性能。

Reduced order observer based identification of base isolated buildings

The objective of this study is to identify system parameters from the recorded response of base isolated buildings,such as USC hospital building,during the 1994 Northridge earthquake.Full state measurements are not available for identification.Additionally,the response is nonlinear due to the yielding of the lead-rubber bearings.Two new approaches are presented in this paper to solve the aforementioned problems.First,a reduced order observer is used to estimate the unmeasured states.Second,a least squares technique with time segments is developed to identify the piece-wise linear system properties.The observer is used to estimate the initial conditions needed for the time segmented identification.A series of equivalent linear system parameters are identified in different time segments.It is shown that the change in system parameters,such as frequencies and damping ratios,due to nonlinear behavior of the lead-rubber bearings,are reliably estimated using the presented technique.It is shown that the response was reduced due to yielding of the lead-rubber bearings and period lengthening.

Observer design and output feedback stabilization for linear singular time-delay systems with unknown inputs

The design of a functional observer and reduced-order observer with internal delay for linear singular timedelay systems with unknown inputs is discussed. The sufficient conditions of the existence of observers, which are normal linear time-delay systems, and the corresponding design steps are presented via linear matrix inequality（LMI）. Moreover, the observer-based feedback stabilizing controller is obtained. Three examples are given to show the effectiveness of the proposed methods.

Study on Four Disturbance Observers for FO-LTI Systems

This paper addresses the problem of designing disturbance observer for fractional order linear time invariant U+0028 FO-LTI U+0029 systems, where the disturbance includes time series expansion disturbance and sinusoidal disturbance. On one hand, the reduced order extended state observer U+0028 ROESO U+0029 and reduced order cascade extended state observer U+0028 ROCESO U+0029 are proposed for the case that the system state can be measured directly. On the other hand, the extended state observer U+0028 ESO U+0029 and the cascade extended state observer U+0028 CESO U+0029 are presented for another case when the system state cannot be measured directly. It is shown that combination of ROCESO and CESO can achieve a highly effective observation result. In addition, the way how to tune observer parameters to ensure the stability of the observers and reduce the observation error is presented in this paper. Finally, numerical simulations are given to illustrate the effectiveness of the proposed methods. © 2014 Chinese Association of Automation.

Design and analysis of switching reduced-order observer and separation principle for T-S fuzzy system

This paper designs and analyzes switching fuzzy reduced-order observer and proves that the corre- sponding separation principle does hold. A numerical simulation and comparison with smooth fuzzy full-order observer are given to assess switching fuzzy reduced-order observer and the validity of the separation principles.

New LMI Conditions for Reduced-order Observer of Lipschitz Discrete-time Systems: Numerical and Experimental Results

The objective of this paper is to propose a reduced-order observer for a class of Lipschitz nonlinear discrete-time systems.The conditions that guarantee the existence of this observer are presented in the form of linear matrix inequalities(LMIs). To handle the Lipschitz nonlinearities, the Lipschitz condition and the Young′s relation are adequately operated to add more degrees of freedom to the proposed LMI. Necessary and sufficient conditions for the existence of the unbiased reduced-order observer are given. An extension to H_∞ performance analysis is considered in order to deal with H_∞ asymptotic stability of the estimation error in the presence of disturbances that affect the state of the system. To highlight the effectiveness of the proposed design methodology, three numerical examples are considered. Then, high performances are shown through real time implementation using the ARDUINO MEGA 2560 device.

基于LADRC的高速龙门式包带机TS-FNN同步控制

针对高速龙门式包带机的驱动过程平行轴产生噪声、振动和卡滞等问题,造成其驱动过程不同步的影响,提出一种降阶扩张状态观测器(reduced-order extended state observer,RESO)的线性自抗扰控制(linear active disturbance rejection contro,LADRC)控制器和TS型模糊神经网络(TS fuzzy neural network,TS-FNN)同步补偿器相结合的控制方法。首先,针对高速龙门式包带机单轴的噪声、摩擦力和振动对伺服系统控制精度的影响,采用RESO的LADRC算法,以抑制控制系统的外部扰动和减少参数调节数量,从而提高位置跟踪精度;同时,针对平行轴中双直线电机因参数摄动和机械耦合等不确定扰动对位置同步精度的影响,采用交叉耦合的控制方法并结合TS-FNN同步补偿器来提高两平行轴的同步精度。通过实验对比验证,所采用的控制策略能有效减少高速龙门式包带机的单轴的跟踪误差,并提高平行轴的同步误差和抗扰性。

风扰下变质量四旋翼轨迹跟踪控制

针对存在风扰和变质量负载扰动的四旋翼无人机轨迹跟踪控制问题,提出了一种基于降阶广义比例积分观测器的动态面模糊滑模控制方法。首先,建立含风扰和变质量负载扰动的四旋翼无人机系统模型;其次,结合四旋翼无人机系统模型设计降阶广义比例积分观测器估计外界风扰;再次,设计动态面滑模控制器,并采用模糊控制模糊化切换增益,以此有效地抑制抖振;然后,通过Lyapunov稳定性证明四旋翼无人机系统的稳定性;最后,通过Matlab-Simulink进行3种控制方法的仿真比较。仿真结果表明,当存在风扰和变质量负载扰动时,该控制方法抗风扰能力更强,稳定性更好,位姿跟踪精度更高。

基于滑模自抗扰的储能变流器控制策略

为了提高储能变流器(PCS)的动态性能,设计基于降阶级联扩张状态观测器(ESO)和互补滑模控制(CSMC)的改进自抗扰控制(ADRC)策略,将改进ADRC策略应用于PCS的双向DC/AC变流器电压外环.改进ESO为降阶级联ESO以提高状态变量和系统总扰动的估计速度,增加扰动估计能力;更改PD控制为CSMC以设计状态误差反馈律,提升PCS的系统鲁棒性;设计改进指数趋近律以抑制抖振现象.为了证明改进ADRC策略相较于PI控制和传统ADRC的优越性,建立仿真模型并搭建相关实验平台.仿真与实验结果表明,改进ADRC策略减小了PCS暂态时直流母线电压波动,提高了PCS交流侧功率响应速度,改善了交流侧的输出电能质量.

电机-变速器集成驱动系统扭转振动控制的研究

针对电动汽车的电机-变速器集成驱动系统,提出了一种线性二次型调节器结合观测器的电机控制方案,以抑制系统的扭转振动。以电机机械角速度、车轮角速度和扭转角作为系统状态变量建立了状态方程,并分析了系统的振动特性。仿真结果表明,观测器能够有效地估计状态变量,线性二次型调节器的采用使系统的振动得到了更好的抑制,提高了车辆的换挡质量和行驶性能。

广义系统降阶正常观测-控制器与双互质分解

首先讨论了真镇定带前通的广义系统的最小阶正常观测-控制器的设计问题,然后基于降阶观测-控制器,明确给出了广义系统双互质分解的一种新的状态空间实现.相应的控制器参数化可以保证是因果的。

基于降阶龙伯格观测器的PMSM模型预测控制

针对永磁同步电机常规模型预测控制在建立预测模型时比较依赖准确的电机数学模型,负载扰动时会对其控制性能造成影响。提出一种基于降阶龙伯格观测器的模型预测控制方法,在电流环采用PI控制器,速度环采用基于负载扰动补偿的模型预测控制器,构建降阶龙伯格观测器对负载扰动进行估算,将估算值补偿到速度环的输出值中来起到抑制扰动的作用。由仿真及实验结果可知,所提算法相比于常规模型预测控制具有更快的动态响应,控制精度更高,有效提高了系统的抗负载干扰性能。

不确定LTI-SISO系统的低通滤波降阶时滞观测器控制

提出一种低通滤波降阶时滞观测器 ,避免了常规时滞观测器控制中由于时滞状态微分近似引起的控制信号颤振。参考模型的选取只与系统的相对阶次有关 ,而与系统阶次无关 ,从而简化了控制器的设计 ,降低了对系统可测性的要求。仿真结果表明 ,该时滞观测器控制系统可以很好地抑制系统的不确定性以及受到的外部干扰 ,是一种性能优良的鲁棒控制方法。

不确定LTI-SISO系统的降阶时滞观测器控制

提出了降阶时滞观测器 ,利用时滞来观测系统的不确定性和受到的外部干扰 ,实现了不确定系统的鲁棒控制 .降阶时滞观测器控制系统中参考模型的阶数由系统的相对阶数决定 ,而与系统阶数无关 ,简化了控制器的设计 ,有利于根据性能指标的要求获得合适的参考模型 .对于相对阶低于系统阶的一般对象 ,通过引入低通滤波器也能实现降阶时滞滤波器控制 .大量的仿真结果表明 ,降阶时滞观测器能够很好地抑制系统的不确定性和受到的外部干扰 ,是一种性能优良的鲁棒控制方法 .

卷到卷制程中基于降维观测器的优化状态反馈控制方法

卷到卷(roll-to-roll,R2R)制程普遍应用于柔性材料的量化生产中,其套色精度是产品质量的关键因素。R2R制程是一个多输入多输出、强耦合的复杂生产过程,实现高速高精度套色控制是其基本要求。首先,根据R2R印刷系统的状态空间模型,设计了基于降维观测器的状态反馈控制方法,同时通过粒子群优化算法对状态反馈的极点进行优化,实现了套色误差的高精度控制。将提出的套色控制方法与最新发表的全解耦比例微分(fully decoupled proportional-derivative,FDPD)套色控制方法进行对比,所提方法在套色精度上获得了50%~80%的提升,调节时间缩短了50%~65%,控制量绝对值之和仅为FDPD控制方法的46%~57%,这不仅减少了对执行机构的冲击,也节约了能量。对比结果证实了降维观测器的估值准确性,也表明所提方法能够明显提高控制性能。

Y-可观广义系统降阶稳态Kalman融合器

对于带多传感器的Y-可观广义线性离散随机系统,通过状态线性变换,将其化为两个降阶的非广义多传感器子系统。应用Kalman滤波方法和白噪声估值器,提出了子系统和原系统的局部状态估值器及它们的误差互协方差公式。在线性最小方差按矩阵加权,按对角阵加权和按标量加权最优信息融合准则下,提出了原系统状态的三种稳态广义Kalman融合器,可统一处理融合滤波、平滑和预报问题,且可改善局部估计精度。

稻麦联合收割机变频驱动液压控制中强扰动问题解决方法

稻麦联合收割机变频驱动液压泵,作为收割机液压系统中重要的动力元件,其在工作中存在非线性时变特征干扰,控制过程中存在的强扰动一直是需要解决的难点,提出一种稻麦联合收割机变频驱动液压控制方法。针对非线性时变特征带来的强扰动问题,设计了降阶负载扰动观测器与转速模糊控制器。将降阶负载扰动观测器、转速模糊控制器与工控计算机、变频器、发动机、液压泵等组件结合起来,构建了强干扰下变频驱动液压泵的自动化控制方法,实现了对液压系统中压力和流量的精确控制。实验结果表明:由该技术控制的收割机转速与流量相对稳定,具有较强的抗干扰性,泵出口压力与最大负载压力的压差较小,高度拟合,且几乎没有溢流损耗,节能效果显著。

鲁棒控制器-观测器在转台控制系统设计与仿真中的应用

采用鲁棒降阶观测器控制器联合设计的方法针对ＨＩＴ３Ｔ２型飞行仿真转台中框控制系统的不确定线性模型设计了中框加速度的鲁棒降维观测器控制器．基于此，对中框控制系统设计了校正网络．仿真结果表明，系统在标称工作点达到了所希望的性能指标，同时具有一定的鲁棒稳定性和鲁棒性能．