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率相关迟滞非线性系统的智能化建模与控制 总被引:1,自引:0,他引:1
提出一种新的率相关迟滞非线性系统的建模方法,并对其在超磁致伸缩作动器建模中的应用进行了研究.与已有的方法比较,所建的模型结构简单.与实验结果对比,模型可以很好地描述作动器对于复合频率输入信号的迟滞非线性.基于模糊树模型,结合神经网络中的逆向学习和专门化学习,提出了一种直接逆模型控制器设计方法.首先离线辨识对象的逆模型作为初始的控制器,然后与对象串联,用LMS算法在线调节控制器中的线性参数.将该方法应用到超磁致伸缩作动器的跟踪控制中,数值仿真结果表明了方法的正确性和可行性. 相似文献
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针对智能材料执行器中非平滑、多映射的迟滞非线性,采用Bouc-Wen模型描述迟滞,并提出了一种基于误差变换的反步控制器设计方案.首先利用Bouc-Wen模型中的变量特性,通过预设性能函数,将误差约束在预设范围内.然后通过误差变换,将一个对输出误差存在约束的跟踪问题转化为一个无约束的镇定问题.最后利用反步控制法设计迟滞系统的控制器,该控制方法保证期望的跟踪精度,并能将误差限定在设定范围内且满足预设性能,提高了系统的暂态和稳态性能.仿真结果表明设计方法的有效性. 相似文献
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针对一类含有迟滞特性的未知控制方向严反馈非线性系统,设计了基于误差变换的反步自适应控制器.首先提出动态迟滞算子来扩展输入空间建立神经网络迟滞模型.然后利用径向基函数(RBF)神经网络逼近未知函数,并引入Nussbaum型函数来解决系统未知控制方向问题.最后采用误差变换将误差限定在预设的范围内,并利用反步法设计自适应控制器.该控制方案不仅能够保证跟踪精度,还可以提高系统暂态和稳态性能.仿真结果表明了控制方案的可行性. 相似文献
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压电陶瓷驱动器的最大迟滞非线性误差可以超过输出行程的15%,而快刀伺服系统(FTS,Fast Tool Servo)要求重复定位精度优于10nm,相对线性度误差优于0.5%,压电陶瓷驱动器的误差无法满足该精度要求。首先对压电陶瓷迟滞非线性误差进行实验分析,将迟滞非线性误差分为频率无关迟滞现象和频率相关迟滞现象。接着对Bouc-Wen(BW)和Prandtl-Ishlinskii(PI)的频率无关迟滞模型进行修正和对比,确定了采用PI模型描述本文的频率无关迟滞现象,PI模型对频率无关迟滞曲线的辨识精度为0.392%。然后设计基于Hammerstein模型的频率相关迟滞模型,Hammerstein模型对频率相关迟滞曲线的辨识误差相比PI模型时,其均方根值降低了88.068%。提出了压电陶瓷驱动器迟滞非线性误差的建模方法,并分析了其有效性和准确性,给FTS伺服控制提供了一种实用的前馈控制器。 相似文献
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针对一类含有Bouc-Wen迟滞的输出受限非线性系统设计了反步控制器.首先分析了Bouc-Wen模型的特性并得到其上界值,然后设计了对称型障碍Lyapunov函数(barrier Lyapunov function,BLF),保证了BLF有界,从而满足了输出受限的条件,最后利用反步法设计控制器.该方法消除了迟滞引起的振荡和超调并且使得系统输出约束在设定的范围内,同时解决了迟滞和系统输出受限两个方面的影响,提高了控制精度.仿真和实验结果表明了控制方法的可行性. 相似文献
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对一类压电迟滞系统模型,设计了3阶滑模跟踪控制器.引入辅助变量项,对3阶滑模函数获得了一种特定动态方程;根据这个动态方程,求出了滑模控制量;采用Lyapunov方法证明并分析了所有滑模平面的稳定性.仿真实验验证了该滑模跟踪控制器的有效性. 相似文献
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基于神经网络的迟滞非线性补偿控制 总被引:1,自引:0,他引:1
提出了一种基于神经网络的迟滞非线性的补偿方法.首先构造一个Duhem逆算子来描述迟滞逆状态.然后利用神经网络来逼近此状态和输出之间的关系来得到神经网络迟滞逆模型,神经网络权值采用反馈误差学习方法来进行在线调整.系统的前馈控制器和反馈控制器分别为逆模型和PID控制器.该方法不需要建立迟滞的正模型,能够在线构造逆模型来实现迟滞补偿.最后通过仿真验证了该方法的有效性. 相似文献
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This paper proposes another adaptive control scheme for nonlinear systems using a Takagi-Sugeno fuzzy model. Takagi-Sugeno
fuzzy models have been widely used to identify the structures and parameters of unknown or partially known plants, and to
control nonlinear systems. This scheme shows a good approximation capability by the fuzzy blending of local dynamics. Since
a Takagi-Sugeno fuzzy model is a nonlinear system in nature, and its parameters are not linearly parameterized, it is difficult
to design an adaptive controller using conventional design methods for adaptive controllers which are derived from linearly
parameterized systems. In this paper, the functional form of the local dynamics are assumed to be known, but the corresponding
parameters are unknown. This additional information about system nonlinearity makes it possible to design an adaptive controller
for a nonlinearly parameterized system. The control law is similar to that of a conventional adaptive control technique, while
its parameter-update rule is based on the local search method. A parameter-update law is derived so that the time-derivative
of the Lyapunov function is negative in the region of interest. Simulation results have shown that this adaptive controller
is capable of a good performance.
This work was presented in part at the Fifth International Symposium on Artificial Life and Robotics, Oita, Japan, January
26–28, 2000 相似文献
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回滞现象广泛存在于许多领域,其不可积的非线性特性给控制设计带来了困难。提出的NBPID控制器是基于神经网络逆模型前馈控制(N),加上改进的Bang—Bang控制(B)的PID控制器。首先通过神经网络逆模型的前馈控制来削弱回滞带来的影响,然后在PID控制器的基础上,为了进一步控制误差,加上改进的Bang—Bang控制。通过设计出的NBPID对回滞系统进行控制,仿真结果表明控制方法是有效的。 相似文献
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Wen-Jeng Liu Kuo-Kai Shyu Kou-Cheng Hsu 《International Journal of Control, Automation and Systems》2011,9(3):461-469
The problem of robust stabilization of a class of uncertain multi-input time-delayed systems with deadzone nonlinearity in
the actuator is considered. To achieve a stable uncertain multi-input system, sliding mode control (SMC) is adopted in the
controller design. The proposed controller guarantees the global reaching condition of the sliding mode in the uncertain multi-input
system. In the sliding mode, the investigated time-delayed systems with deadzone nonlinearity still possess the insensitivity
to the uncertainties and/or disturbances, which can be seen in the systems with linear inputs. In addition, the proposed controller
can work effectively for systems no matter whether sector nonlinearity and/or deadzone exists in the actuator or not. However,
such property cannot be obtained by the controller design through traditional SMC for the systems without input nonlinearity.
Besides, the traditional SMC controller might produce limit cycles once the system contains deadzone in the input. Furthermore,
the presented controller ensures the system trajectories globally exponentially converged in the sliding mode. Finally, two
examples are illustrated to demonstrate the effectiveness of the proposed sliding mode controller. 相似文献
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S.I. Biagiola 《International journal of control》2013,86(3):432-444
Block-oriented models (BOMs) have shown to be appealing and efficient as nonlinear representations for many applications. They are at the same time valid and simple models in a more extensive region than time-invariant linear models. In this work, Wiener models are considered. They are one of the most diffused BOMs, and their structure consists in a linear dynamics in cascade with a nonlinear static block. Particularly, the problem of control of these systems in the presence of uncertainty is treated. The proposed methodology makes use of a robust identification procedure in order to obtain a robust model to represent the uncertain system. This model is then employed to design a model predictive controller. The mathematical problem involved in the controller design is formulated in the context of the existing linear matrix inequalities (LMI) theory. The main feature of this approach is that it takes advantage of the static nature of the nonlinearity, which allows to solve the control problem by focusing only in the linear dynamics. This formulation results in a simplified design procedure, because the original nonlinear model predictive control (MPC) problem turns into a linear one. 相似文献
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许多实际系统可以表示为不连续非线性块状结构模型,其不连续非线性部分常采用符号函数参数化,该处理方法适用于递推参数辨识,但自适应控制器的设计较为困难。鉴于此,针对一类含有不连续非线性环节的Hammerstein模型,采用一系列线性分段函数参数化不连续非线性环节,提出自校正控制方法。根据线性分段函数的逆函数特性,求解自适应控制律。理论分析证明了闭环系统的稳定性,仿真结果验证了所提出方法的有效性。 相似文献
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本文针对具有强非线性、多工作点特性的控制系统, 提出了一种基于递归BP神经网络的多步预测模型; 通过分析预测模型的内在数学关系, 选择了二次型函数作为预测控制器的目标函数, 并给出了目标函数关于控制序列的雅可比矩阵和赫森矩阵的计算方法; 最后使用Newton-Rhapson算法设计出了滚动优化控制策略, 构建了一个非线性多步预测控制器. 仿真结果表明, 文中提出的多步预测控制器具有较好的控制效果. 相似文献
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Quanmin Zhu Yongji Wang Dongya Zhao Shaoyuan Li Stephen A. Billings 《International journal of systems science》2013,44(12):2122-2133
This paper is a summary of the research development in the rational (total) nonlinear dynamic modelling over the last two decades. Total nonlinear dynamic systems are defined as those where the model parameters and input (controller outputs) are subject to nonlinear to the output. Previously, this class of models has been known as rational models, which is a model that can be considered to belong to the nonlinear autoregressive moving average with exogenous input (NARMAX) model subset and is an extension of the well-known polynomial NARMAX model. The justification for using the rational model is that it provides a very concise and parsimonious representation for highly complex nonlinear dynamic systems and has excellent interpolatory and extrapolatory properties. However, model identification and controller design are much more challenging compared to the polynomial models. This has been a new and fascinating research trend in the area of mathematical modelling, control, and applications, but still within a limited research community. This paper brings several representative algorithms together, developed by the authors and their colleagues, to form an easily referenced archive for promotion of the awareness, tutorial, applications, and even further research expansion. 相似文献
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为了提高Buck变换器控制系统的设计精度和效率,对Buck变换器非线性建模及控制器的设计进行了研究。结合U模型不损失NARMAX模型非线性特性且易于设计控制器的特点,提出了一个基于输入输出数据的NARMAX建模方法,根据模型的残差,进行了相关性检验以验证模型的有效性。通过将NARMAX模型转化为U模型并基于U模型设计了Buck变换器的极点配置控制器。仿真结果显示,基于U模型的Buck变换器极点配置控制器在调节时间和超调量控制上优于传统的PID控制器。 相似文献
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输出反馈控制是T-S模糊控制系统设计的一种重要方法.本文提出了一类由模糊状态观测器和模糊调节器构成的输出反馈控制器稳定性分析和解析设计的新方法.为了减小稳定性分析的保守性和难度,本文充分利用了模糊规则前件变量模糊隶属度函数的结构信息,对前件变量采用标准模糊分划的T-S模糊系统输出反馈控制器进行了研究,获得了一些新的稳定性条件.然后采用平行分布补偿法(PDC)和线性矩阵不等式方法(LMI),研究了该类输出反馈控制器的解析设计方法.通过一个非线性质量块-弹簧-阻尼器系统输出反馈控制器的设计和计算机仿真,验证了本文方法的有效性. 相似文献