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EFFECTIVE DOUBLE LOOP CONTROL FOR A SQUARE WAVE BRUSHLESS DC MOTOR
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作者 周波 李先祥 朱震莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期34+30-33,共5页
A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yie... A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yields a combination of desired characteristics including simplified control structure, small ripple torque, high speed accuracy, wide operating speed range, and fast dynamic response. Experimental results confirm excellent characteristics of the motor. 展开更多
关键词 synchronous motors speed control systems INVERTERS brushless DC motor double loop control square wave motors
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Temperature prediction control based on least squares support vector machines 被引量:5
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作者 BinLIU HongyeSU +1 位作者 WeihuaHUANG JianCHU 《控制理论与应用(英文版)》 EI 2004年第4期365-370,共6页
A prediction control algorithm is presented based on least squares support vector machines (LS-SVM) model for a class of complex systems with strong nonlinearity. The nonlinear off-line model of the controlled plant i... A prediction control algorithm is presented based on least squares support vector machines (LS-SVM) model for a class of complex systems with strong nonlinearity. The nonlinear off-line model of the controlled plant is built by LS-SVM with radial basis function (RBF) kernel. In the process of system running, the off-line model is linearized at each sampling instant, and the generalized prediction control (GPC) algorithm is employed to implement the prediction control for the controlled plant. The obtained algorithm is applied to a boiler temperature control system with complicated nonlinearity and large time delay. The results of the experiment verify the effectiveness and merit of the algorithm. 展开更多
关键词 Predictive control Least squares support vector machines RBF kernel function Generalized prediction control
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Least Squares Solution for Discrete Time Nonlinear Stochastic Optimal Control Problem with Model-Reality Differences 被引量:2
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作者 Sie Long Kek Jiao Li Kok Lay Teo 《Applied Mathematics》 2017年第1期1-14,共14页
In this paper, an efficient computational approach is proposed to solve the discrete time nonlinear stochastic optimal control problem. For this purpose, a linear quadratic regulator model, which is a linear dynamical... In this paper, an efficient computational approach is proposed to solve the discrete time nonlinear stochastic optimal control problem. For this purpose, a linear quadratic regulator model, which is a linear dynamical system with the quadratic criterion cost function, is employed. In our approach, the model-based optimal control problem is reformulated into the input-output equations. In this way, the Hankel matrix and the observability matrix are constructed. Further, the sum squares of output error is defined. In these point of views, the least squares optimization problem is introduced, so as the differences between the real output and the model output could be calculated. Applying the first-order derivative to the sum squares of output error, the necessary condition is then derived. After some algebraic manipulations, the optimal control law is produced. By substituting this control policy into the input-output equations, the model output is updated iteratively. For illustration, an example of the direct current and alternating current converter problem is studied. As a result, the model output trajectory of the least squares solution is close to the real output with the smallest sum squares of output error. In conclusion, the efficiency and the accuracy of the approach proposed are highly presented. 展开更多
关键词 Least squareS SOLUTION STOCHASTIC Optimal control Linear Quadratic REGULATOR Sum squareS of Output Error INPUT-OUTPUT Equations
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Flatness intelligent control via improved least squares support vector regression algorithm 被引量:2
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作者 张秀玲 张少宇 +1 位作者 赵文保 徐腾 《Journal of Central South University》 SCIE EI CAS 2013年第3期688-695,共8页
To overcome the disadvantage that the standard least squares support vector regression(LS-SVR) algorithm is not suitable to multiple-input multiple-output(MIMO) system modelling directly,an improved LS-SVR algorithm w... To overcome the disadvantage that the standard least squares support vector regression(LS-SVR) algorithm is not suitable to multiple-input multiple-output(MIMO) system modelling directly,an improved LS-SVR algorithm which was defined as multi-output least squares support vector regression(MLSSVR) was put forward by adding samples' absolute errors in objective function and applied to flatness intelligent control.To solve the poor-precision problem of the control scheme based on effective matrix in flatness control,the predictive control was introduced into the control system and the effective matrix-predictive flatness control method was proposed by combining the merits of the two methods.Simulation experiment was conducted on 900HC reversible cold roll.The performance of effective matrix method and the effective matrix-predictive control method were compared,and the results demonstrate the validity of the effective matrix-predictive control method. 展开更多
关键词 least squares support vector regression multi-output least squares support vector regression FLATNESS effective matrix predictive control
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New predictive control algorithms based on Least Squares Support Vector Machines 被引量:3
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作者 刘斌 苏宏业 褚健 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第5期440-446,共7页
Used for industrial process with different degree of nonlinearity, the two predictive control algorithms presented in this paper are based on Least Squares Support Vector Machines (LS-SVM) model. For the weakly nonlin... Used for industrial process with different degree of nonlinearity, the two predictive control algorithms presented in this paper are based on Least Squares Support Vector Machines (LS-SVM) model. For the weakly nonlinear system, the system model is built by using LS-SVM with linear kernel function, and then the obtained linear LS-SVM model is transformed into linear input-output relation of the controlled system. However, for the strongly nonlinear system, the off-line model of the controlled system is built by using LS-SVM with Radial Basis Function (RBF) kernel. The obtained nonlinear LS-SVM model is linearized at each sampling instant of system running, after which the on-line linear input-output model of the system is built. Based on the obtained linear input-output model, the Generalized Predictive Control (GPC) algorithm is employed to implement predictive control for the controlled plant in both algorithms. The simulation results after the presented algorithms were implemented in two different industrial processes model; respectively revealed the effectiveness and merit of both algorithms. 展开更多
关键词 Least squares Support Vector Machines Linear kernel function RBF kernel function Generalized predictive control
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Adaptive control of machining process based on extended entropy square error and wavelet neural network 被引量:2
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作者 赖兴余 叶邦彦 +1 位作者 李伟光 鄢春艳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第3期349-353,共5页
Combining information entropy and wavelet analysis with neural network,an adaptive control system and an adaptive control algorithm are presented for machining process based on extended entropy square error(EESE)and w... Combining information entropy and wavelet analysis with neural network,an adaptive control system and an adaptive control algorithm are presented for machining process based on extended entropy square error(EESE)and wavelet neural network(WNN).Extended entropy square error function is defined and its availability is proved theoretically.Replacing the mean square error criterion of BP algorithm with the EESE criterion,the proposed system is then applied to the on-line control of the cutting force with variable cutting parameters by searching adaptively wavelet base function and self adjusting scaling parameter,translating parameter of the wavelet and neural network weights.Simulation results show that the designed system is of fast response,non-overshoot and it is more effective than the conventional adaptive control of machining process based on the neural network.The suggested algorithm can adaptively adjust the feed rate on-line till achieving a constant cutting force approaching the reference force in varied cutting conditions,thus improving the machining efficiency and protecting the tool. 展开更多
关键词 machining process adaptive control extended entropy square error wavelet neural network
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Consistency and Asymptotic Property of a Weighted Least Squares Method for Networked Control Systems 被引量:1
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作者 张聪 叶昊 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期754-761,共8页
In this paper, we study the problems related to parameter estimation of a single-input and single-output networked control system, which contains possible network-induced delays and packet dropout in both of sensor-to... In this paper, we study the problems related to parameter estimation of a single-input and single-output networked control system, which contains possible network-induced delays and packet dropout in both of sensor-to-controller path and controller-to-actuator path. A weighted least squares(WLS) method is designed to estimate the parameters of plant, which could overcome the data uncertainty problem caused by delays and dropout. This WLS method is proved to be consistent and has a good asymptotic property. Simulation examples are given to validate the results. 展开更多
关键词 Networked control system Network-induced delay Packet dropout Weighted least squares CONSISTENCY Asymptotic property
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Generalized Predictive Control with Online Least Squares Support Vector Machines 被引量:41
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作者 LI Li-Juan SU Hong-Ye CHU Jian 《自动化学报》 EI CSCD 北大核心 2007年第11期1182-1188,共7页
这份报纸基于能有效地处理非线性的系统的联机最少的广场支持向量机器(LS-SVM ) 建议一个实际概括预兆的控制(GPC ) 算法。在每个采样时期,算法递归地由增加新数据对并且在实时性质上从考虑删除最不重要的修改模型。删除的数据对被 lag... 这份报纸基于能有效地处理非线性的系统的联机最少的广场支持向量机器(LS-SVM ) 建议一个实际概括预兆的控制(GPC ) 算法。在每个采样时期,算法递归地由增加新数据对并且在实时性质上从考虑删除最不重要的修改模型。删除的数据对被 lagrange 的绝对值从最后一个采样时期更多样地决定。当增加新数据对并且删除存在的时,纸给模型参数的递归的算法分别地,一个大矩阵的倒置被避免,存储器能被算法完全控制。非线性的 LS-SVM 模型在每个采样时期在 GPC 算法被使用。抵销过程的 pH 上的概括预兆的控制的实验显示出建议算法的有效性和实物。 展开更多
关键词 普遍预测控制 支持向量机 联机模型 pH补偿过程 模糊控制
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Modified Two-Degrees-of-Freedom Internal Model Control for Non-Square Systems with Multiple Time Delays 被引量:25
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作者 Jian-Chang Liu Nan Chen Xia Yu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期122-128,共7页
A modified two-degrees-of-freedom( M-TDOF) internal model control( IMC) method is proposed for non-square systems with multiple time delays and right-half-plane( RHP) zeros. In this method,pseudo-inverse is introduced... A modified two-degrees-of-freedom( M-TDOF) internal model control( IMC) method is proposed for non-square systems with multiple time delays and right-half-plane( RHP) zeros. In this method,pseudo-inverse is introduced to design the internal model controller,and a desired closed-loop transfer function is designed to eliminate the unrealizable factors of the derived controller. In addition,set-point tracking and load-disturbance rejection of each process are separately controlled by two controllers. The simulation results show that in addition to high decoupling performance and robustness,the proposed control method also effectively improves loaddisturbance rejection and simultaneously optimizes the input tracking performance and disturbance rejection performance by selecting the parameters of controllers. Furthermore,the higher tolerance of model mismatch is achieved in this paper. 展开更多
关键词 non-square system two degrees of freedom internal model control
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Robust Control Synthesis of Polynomial Nonlinear Systems Using Sum of Squares Technique 被引量:3
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作者 HUANG Wen-Chao SUN Hong-Fei ZENG Jian-Ping 《自动化学报》 EI CSCD 北大核心 2013年第6期799-805,共7页
在这篇论文,广场(求救) 加技术被用来与多项式向量领域为不明确的仿射的非线性的系统的一个类分析柔韧的州的反馈合成问题。没有或与保证费用或 Hperformance 目的,足够的条件被给获得答案到上述控制问题。而且,如此的可解决的条件... 在这篇论文,广场(求救) 加技术被用来与多项式向量领域为不明确的仿射的非线性的系统的一个类分析柔韧的州的反馈合成问题。没有或与保证费用或 Hperformance 目的,足够的条件被给获得答案到上述控制问题。而且,如此的可解决的条件能以能被 SOS 技术直接处理的州的依赖线性矩阵不平等(LMI ) 作为求救编程问题被提出。而且,一个想法被提供由介绍一些额外的多项式描述多项式或甚至合理的矩阵的逆。一个数字例子被举说明途径的有效性。 展开更多
关键词 多项式向量场 仿射非线性系统 合成技术 鲁棒控制 平方和 线性矩阵不等式 状态反馈 SOS
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Mean Square Containment Control of Multi-agent Systems with Transmission Noises 被引量:3
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作者 LIU Shuai XIE Li-Hua ZHANG Huan-Shui 《自动化学报》 EI CSCD 北大核心 2013年第11期1787-1795,共9页
为有传播噪音的多代理人系统的抑制控制问题被考虑。由于噪音的存在,腐烂的获得功能被介绍稀释噪音。动态地交换拓扑学并且随机交换拓扑学被考虑。通讯图和控制获得功能上的足够的条件被导出保证吝啬的方形的抑制。一些数字例子被提供... 为有传播噪音的多代理人系统的抑制控制问题被考虑。由于噪音的存在,腐烂的获得功能被介绍稀释噪音。动态地交换拓扑学并且随机交换拓扑学被考虑。通讯图和控制获得功能上的足够的条件被导出保证吝啬的方形的抑制。一些数字例子被提供验证结果。 展开更多
关键词 多智能体系统 传动噪声 控制问题 广场 增益函数 随机开关 动态开关 充分条件
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Identification of time-varying system and energy-based optimization of adaptive control in seismically excited structure
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作者 Elham Aghabarari Fereidoun Amini Pedram Ghaderi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期227-240,共14页
The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible ... The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible with changing conditions still needs to be used,and time-varying systems are required to be simultaneously estimated with the application of adaptive control.In this research,the identification of structural time-varying dynamic characteristics and optimized simple adaptive control are integrated.First,reduced variations of physical parameters are estimated online using the multiple forgetting factor recursive least squares(MFRLS)method.Then,the energy from the structural vibration is simultaneously specified to optimize the control force with the identified parameters to be operational.Optimization is also performed based on the probability density function of the energy under the seismic excitation at any time.Finally,the optimal control force is obtained by the simple adaptive control(SAC)algorithm and energy coefficient.A numerical example and benchmark structure are employed to investigate the efficiency of the proposed approach.The simulation results revealed the effectiveness of the integrated online identification and optimal adaptive control in systems. 展开更多
关键词 integrated online identification time-varying systems structural energy multiple forgetting factor recursive least squares optimal simple adaptive control algorithm
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Mean-Square Exponential Input-to-State Stability of Numerical Solutions for Stochastic Control Systems 被引量:1
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作者 Qiao ZHU Jia-Rui CUI Guang-Da HU 《自动化学报》 EI CSCD 北大核心 2013年第8期1360-1365,共6页
这份报纸处理随机的控制系统(SCS ) 的数字解决方案的吝啬平方的指数的 input-to-state 稳定性(expbe ) 。第一,一个有限时间的强壮的集中条件成立为,这被显示出随机 ? SCS 上的方法。那么,如果并且仅当,我们能看到 SCS 的吝啬平方... 这份报纸处理随机的控制系统(SCS ) 的数字解决方案的吝啬平方的指数的 input-to-state 稳定性(expbe ) 。第一,一个有限时间的强壮的集中条件成立为,这被显示出随机 ? SCS 上的方法。那么,如果并且仅当,我们能看到 SCS 的吝啬平方的 expbe 成立的随机 ? 方法(为足够地小的步尺寸) 在有限时间的强壮的集中条件下面被保存。为有片面 Lipschitz 飘移的 SCS 的一个班,第二,它被证明那二含蓄的 Euler 方法(为任何步尺寸) 能继承 SCS 的吝啬平方的 expbe 性质。最后,数字例子证实在这研究介绍的定理的正确性。 展开更多
关键词 随机控制系统 状态稳定性 数值解 输入 LIPSCHITZ 隐式Euler方法 有限时间 收敛条件
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Mean-square Exponential Input-to-state Stability of Euler-Maruyama Method Applied to Stochastic Control Systems 被引量:4
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作者 ZHU Qiao HU Guang-Da ZENG Li 《自动化学报》 EI CSCD 北大核心 2010年第3期406-411,共6页
关键词 均方指数 收敛性 连续随机函数 控制方法
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NOVEL WEIGHTED LEAST SQUARES SUPPORT VECTOR REGRESSION FOR THRUST ESTIMATION ON PERFORMANCE DETERIORATION OF AERO-ENGINE 被引量:2
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作者 苏伟生 赵永平 孙健国 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期25-32,共8页
A thrust estimator with high precision and excellent real-time performance is needed to mitigate perfor- mance deterioration for future aero-engines. A weight least squares support vector regression is proposed using ... A thrust estimator with high precision and excellent real-time performance is needed to mitigate perfor- mance deterioration for future aero-engines. A weight least squares support vector regression is proposed using a novel weighting strategy. Then a thrust estimator based on the proposed regression is designed for the perfor- mance deterioration. Compared with the existing weighting strategy, the novel one not only satisfies the require- ment of precision but also enhances the real-time performance. Finally, numerical experiments demonstrate the effectiveness and feasibility of the proposed weighted least squares support vector regression for thrust estimator. Key words : intelligent engine control; least squares ; support vector machine ; performance deterioration 展开更多
关键词 intelligent engine control least squares support vector machine performance deterioration
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BOOSTING SPARSE LEAST SQUARES SUPPORT VECTOR REGRESSION (BSLSSVR) AND ITS APPLICATION TO THRUST ESTIMATION 被引量:2
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作者 赵永平 孙健国 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第4期254-261,共8页
In order to realize direct thrust control instead of conventional sensors-based control for aero-engine, a thrust estimator with high accuracy is designed by using the boosting technique to improve the performance of ... In order to realize direct thrust control instead of conventional sensors-based control for aero-engine, a thrust estimator with high accuracy is designed by using the boosting technique to improve the performance of least squares support vector regression (LSSVR). There exist two distinct features compared with the conven- tional boosting technique: (1) Sampling without replacement is used to avoid numerical instability for modeling LSSVR. (2) To realize the sparseness of LSSVR and reduce the computational complexity, only a subset of the training samples is used to construct LSSVR. Thus, this boosting method for LSSVR is called the boosting sparse LSSVR (BSLSSVR). Finally, simulation results show that BSLSSVR-based thrust estimator can satisfy the requirement of direct thrust control, i.e. , maximum absolute value of relative error of thrust estimation is not more than 5‰. 展开更多
关键词 least squares support vector machines direct thrust control boosting technique
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单值分解和Chi-square技术在生化反应过程控制中的应用
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作者 李延科 张淑芬 杨锦宗 《化工学报》 EI CAS CSCD 北大核心 2003年第9期1326-1329,共4页
In this paper Singular Decompositon Value (SVD) formula and modified Chi-square solution are provided, and the modified Chi-square is combined with FT-IR instrument to control biochemical reaction process. Using the m... In this paper Singular Decompositon Value (SVD) formula and modified Chi-square solution are provided, and the modified Chi-square is combined with FT-IR instrument to control biochemical reaction process. Using the modified Chi-square technique, the unknown concentration of reactants and products in test samples withdrawn from the process is determined. The technique avoids the need for the spectral data to conform to Beer’s Law and the best spectral range is determined automatically. 展开更多
关键词 单值分解 CHI-square FT-IR波谱仪 过程控制
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Stochastic Maximum Principle for Square-Integrable Optimal Control of Linear Stochastic Systems
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作者 Shanjian TANG Xueqi WANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2024年第5期661-676,共16页
The authors give a stochastic maximum principle for square-integrable optimal control of linear stochastic systems.The control domain is not necessarily convex and the cost functional can have a quadratic growth.In pa... The authors give a stochastic maximum principle for square-integrable optimal control of linear stochastic systems.The control domain is not necessarily convex and the cost functional can have a quadratic growth.In particular,they give a stochastic maximum principle for the linear quadratic optimal control problem. 展开更多
关键词 Stochastic maximum principle Optimal control Linear stochastic system square integrability
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基于Sum of Squares分解技术的电力系统鲁棒综合控制方法 被引量:2
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作者 陈明媛 王钧 +2 位作者 周智成 谢代钰 潘连荣 《电机与控制应用》 2021年第9期81-89,共9页
针对具有不确定干扰的汽轮发电机励磁与汽阀综合控制系统,建立鲁棒综合控制模型。运用基于Sum of Squares(SOS)分解技术的鲁棒控制方法(SOSRCA),设计电力系统鲁棒综合控制方法。该方法充分考虑了综合系统中存在的不确定参数及干扰,使发... 针对具有不确定干扰的汽轮发电机励磁与汽阀综合控制系统,建立鲁棒综合控制模型。运用基于Sum of Squares(SOS)分解技术的鲁棒控制方法(SOSRCA),设计电力系统鲁棒综合控制方法。该方法充分考虑了综合系统中存在的不确定参数及干扰,使发电机组具有较好的鲁棒性能。控制方法的求解过程是算法化、程序化的,避免了繁琐的递归设计和参数估计过程。最后,在三机电力系统仿真中,对基于SOSRCA所得出的鲁棒综合控制律进行仿真分析与讨论,验证其有效性及优越性。 展开更多
关键词 励磁与汽阀综合控制 SOS分解技术 SOS鲁棒控制方法(SOSRCA) 鲁棒性能
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Robust On-Line Fault Diagnosis for Nonlinear Difference-Algebraic Systems Using Least Squares Estimate
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作者 Chen Yudong, Weng Zhengxin & Shi SongjiaoInstitute of Automation, Shanghai Jiaotong University, Shanghai 200030, P.R. China(Received April 9,2001) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第2期50-59,共10页
A robust on-line fault diagnosis methor based on least squares estimate for nonlinear difference-algebraic systems (DAS) with uncertainties is proposed. Based on the known nominal model of the DAS, this method firstly... A robust on-line fault diagnosis methor based on least squares estimate for nonlinear difference-algebraic systems (DAS) with uncertainties is proposed. Based on the known nominal model of the DAS, this method firstly constructs an auxiliary system consisting of a difference equation and an algebraic equation, then, based on the relationship between the state deviation and the faults in the difference equation and the relationship between the algebraic variable deviation and the faults in algebraic equation, it identifies the faults on-line through least squares estimate. This method can not only detect, isolate and identify faults for DAS, but also give the upper bound of the error of fault identification. The simulation results indicate that it can give satisfactory diagnostic results for both abrupt and incipient faults. 展开更多
关键词 Difference equations Least squares approximations Robustness (control systems) Sensitivity analysis
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