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1.
Anti‐disturbance control and estimation problem is introduced for a class of nonlinear system subject to disturbances. The adaptive disturbance observers are constructed separately from the controller design to estimate the disturbance with partial known information. By integrating disturbance‐observer‐based control with fuzzy control, a novel type of composite hierarchical anti‐disturbance control scheme is presented for a class of nonlinear system with unknown nonlinear dynamics. Simulations for a flight control system are given to demonstrate the effectiveness of the results compared with the previous schemes.Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
2.
This paper addresses the problems of disturbance estimation and anti‐disturbance control for nonlinear system with exogenous disturbance, which is generated from an unknown exogenous system. The state observer and the adaptive disturbance observer are designed, simultaneously. Compared with the existing methods, which assumed that the exogenous system parameter matrix was known, our disturbance observer is more applicable in practice. Utilizing the estimation information, an observer‐based dynamic output feedback controller is designed, which avoids the influence of output disturbance on the closed‐loop system, and contains a disturbance compensation term to compensate the input disturbance. Finally, simulations are provided to demonstrate the effectiveness of the proposed approach. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
3.
Antidisturbance control problem is discussed for stochastic systems with multiple heterogeneous disturbances, which include the white noise and the disturbance with unknown frequencies and amplitudes. An adaptive disturbance observer is designed to estimate the disturbance with unknown frequencies and amplitudes, based on which, an adaptive disturbance observer‐based control scheme is proposed by combining adaptive technique and linear matrix inequality method. It is proved that the closed‐loop system is asymptotically bounded in mean square when multiple heterogeneous disturbances exist simultaneously and that the equilibrium is globally asymptotically stable in probability as additive disturbance disappears. Finally, two simulation examples, including a wind turbine system, are given to show the effectiveness of the proposed scheme. 相似文献
4.
Current‐mode control is a robust industrial DC–DC power converter control scheme that has been successfully tested, is widely accepted, and is commonly implemented with conventional linear P and PI controllers. The need of more systematic designs with enhanced performance has motivated recent studies with linear and nonlinear advanced techniques, but the rigorous understanding and substantiation of the underlying key robust functioning capability are still lacking. In this paper, a constructive control approach is employed to study the current‐mode control problem of a class of DC–DC power converters, yielding a cascade control design methodology with: a robust convergence criterion coupled with a systematic and transparent construction‐tuning procedure, a rationale to explain the robust controller functioning, and a unified framework to interpret and compare the proposed controller with the existing conventional and advanced control designs. The implementation and functioning of the proposed control design is illustrated experimentally with a boost converter. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
5.
In this paper, a class of fractional‐order nonlinear systems are considered in the presence of actuator faults. A novel fault tolerant control scheme based on disturbance observer has been presented, where the actuator faults are considered as the system disturbance and can be approximated by the proposed disturbance observer. The developed fault tolerant control guarantees the convergence of the closed‐loop system and the output tracking performance. Finally, a simulation example is presented to verify the effectiveness of the new method. 相似文献
6.
This paper gives an overview of early development of nonlinear disturbance observer design technique and the disturbanceobserver based control (DOBC) design. Some critical points raised in the development of the methods have been reviewed anddiscussed which are still relevant for many researchers or practitioners who are interested in this method. The review is followedby the development of a new type of nonlinear PID controller for a robotic manipulator and its experimental tests. It is shown that,under a number of assumptions, the DOBC consisting of a predictive control method and a nonlinear disturbance observer couldreduce to a nonlinear PID with special features. Experimental results show that, compared with the predictive control method,the developed controller significantly improves performance robustness against uncertainty and friction. This paper may triggerfurther research and interests in the development of DOBC and related methods, and building up more understanding betweenthis group of control methods with comparable ones (particularly control methods with integral action). 相似文献
7.
Wen-Hua CHEN 《控制理论与应用(英文版)》2018,16(4):284-300
This paper gives an overview of early development of nonlinear disturbance observer design technique and the disturbanceobserver based control (DOBC) design. Some critical points raised in the development of the methods have been reviewed anddiscussed which are still relevant for many researchers or practitioners who are interested in this method. The review is followedby the development of a new type of nonlinear PID controller for a robotic manipulator and its experimental tests. It is shown that,under a number of assumptions, the DOBC consisting of a predictive control method and a nonlinear disturbance observer couldreduce to a nonlinear PID with special features. Experimental results show that, compared with the predictive control method,the developed controller significantly improves performance robustness against uncertainty and friction. This paper may triggerfurther research and interests in the development of DOBC and related methods, and building up more understanding betweenthis group of control methods with comparable ones (particularly control methods with integral action). 相似文献
8.
Abdesselem Boulkroune Mohamed Tadjine Mohammed M'Saad Mondher Farza 《International journal of systems science》2013,44(4):367-382
In this article, the direct adaptive fuzzy control problem is investigated for a class of general non-linear systems with zero dynamics. The direct adaptive fuzzy controller is developed based on a unified observer which is used to estimate the time derivatives of the output. The corrective term of the proposed observer involves a well-defined design function which is shown to be satisfied by the commonly used high-gain-based observers, namely for the usual high-gain observers and the sliding-mode observers together with their implementable versions. By using a general error function, and without resorting to the famous strictly positive real condition or the filtering of the observation error, a general proportional–integral (PI) law for updating the fuzzy parameters is proposed. Ultimately boundedness of the error signals is shown through Lyapunov's direct method. Theoretical results are illustrated through two simulation examples. 相似文献
9.
针对一类带有多源干扰的随机系统,研究其抗干扰控制问题.针对可以由未知参数的外源系统产生,代表频率、振幅和初相都未知的干扰,构建随机自适应干扰观测器对其进行估计.基于此,结合自适应控制和随机控制的方法,提出基于干扰观测器的抗干扰控制策略,保证复合系统的所有信号均为均方渐近有界.仿真结果验证了所提出方法的正确性和有效性. 相似文献
10.
This paper proposes a new backstepping approach to nonlinear control of power converters which is attracting considerable attention in both theoretical research and practical applications. The main difference between the proposed algorithm and the existing classical adaptive backstepping method in the literature is that the adaptation mechanism does not follow the certainty‐equivalence principle. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
11.
针对永磁同步电机伺服系统的跟踪控制问题,提出了一种基于扰动观测器的自适应模糊滑模控制方法.通过扰动观测器估计等效扰动,改善了系统的动态性能和稳态性能,并且只需要等效扰动的变化有界,而不是为零,放宽了要求;根据模糊控制原理引入3条模糊规则,在保证滑模条件的前提下有效地削弱了抖振;采用自适应策略估计模糊系统参数的最优值,简化了控制器的设计.实验结果表明,与常规自适应模糊滑模控制相比,本文提出的控制方法不仅能够有效地减小跟踪误差,而且能够改善参数估计过程,保证了参数估计的有界性. 相似文献
12.
A novel type of control scheme combining the disturbance‐observer‐based control (DOBC) with H∞ control is proposed for a class of complex continuous models with disturbances. The disturbances are supposed to include two parts. One part in the input channel is generated by an exogenous system with uncertainty, which can represent the harmonic signals with modeling perturbations. The other part is supposed to have the bounded H2‐norm. Parametric uncertainties exist both in concerned plant and in exogenous subsystem. The disturbance observers based on regional pole placement and D‐stability theory are designed and integrated with conventional H∞ control laws. The new composite DOBC and H∞ control scheme is applied to complex continuous models for the case with known and unknown nonlinearity, respectively. Then the first type of disturbances can be estimated and rejected, and the second type can be attenuated; simultaneously, the desired dynamic performances can be guaranteed. Simulations for a flight control system are given to demonstrate the effectiveness of the results and compare the proposed results with the previous schemes. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
13.
本文针对在模型不确定性、外界干扰与执行器故障影响下柔性航天器姿态控制问题,设计一种自适应容错控制算法,该算法包括标称控制部分和补偿控制部分.首先,标称控制部分用于实现不考虑综合不确定影响下航天器有限时间姿态控制;其次,补偿控制部分基于积分滑模理论进行设计,该补偿控制器通过对综合不确定有效估计,在控制器中作补偿,减少对姿态控制精度的影响,提高航天器姿态控制精度.该算法特点在于可实现柔性航天器全局有限时间姿态控制,放宽角速度或其导数、执行器故障或其导数有界的假设.同时,基于Lyapunov函数严格证明整个闭环系统的稳定性.最后,通过仿真验证该控制算法的有效性. 相似文献
14.
This paper investigates the design problem of composite antidisturbance control for a class of nonlinear systems with multiple disturbances. First, a novel nonlinear disturbance observer‐based control scheme is constructed to estimate and compensate the disturbance modeled by the nonlinear exosystem. Then, by combining the dissipative control theory, a linear matrix inequality‐based design method of composite antidisturbance control is developed such that the augmented system is exponentially stable in the absence of unmodeled disturbances, and is dissipative in the presence of unmodeled disturbances. In this case, the original closed‐loop system is exponentially stable in the presence of modeled disturbances. Subsequently, two special cases of composite antidisturbance control are derived with H∞ performance and passivity, respectively. Finally, the proposed method is applied to control A4D aircraft to show its effectiveness. 相似文献
15.
Anti‐disturbance control and estimation problem are investigated for nonlinear system subject to multi‐source disturbances. The disturbances classified model is proposed based on the error and noise analysis of priori knowledge. The disturbance observers are constructed separately from the controller design to estimate the disturbance with partial known information. By integrating disturbance‐observer‐based control with discrete‐time sliding‐mode control (DSMC), a novel type of composite stratified anti‐disturbance control scheme is presented for a class of multiple‐input–multiple‐output discrete‐time systems with known and unknown nonlinear dynamics, respectively. Simulations for a flight control system are given to demonstrate the effectiveness of the results compared with the previous schemes. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
16.
A novel nonlinear observer‐based adaptive disturbance attenuation control strategy was proposed for a quarter semi‐active suspension system with a magneto‐rheological (MR) damper in light of the intrinsic nonlinearity, parameter uncertainty, state immeasurability and road randomness. Adaptive adjusting parameters were adopted to avoid the curve fitting and identification of the system parameters by a great deal of experimental data for shortening the development cycle of the control system. Based on the reduced‐order observer, the system states including the immeasurable virtual state of MR damper and inconveniently measured states of suspension system were estimated for the realistic frame of the proposed controller in practice. The dissipative system theory was utilized to reduce the influence of the road disturbance on the system control performance. Simulation results in the bump road and B‐class road indicate that, whether there are perturbations of the system parameters or not, the proposed control scheme always ensures a better performance on the suspension travel, ride comfort and handling stability in comparison with other existing methods. 相似文献
17.
为了使水面无人船(USV)获得更好的跟踪性能,本文设计了基于扰动观测器和命令滤波器的自适应模糊控制器.对于该系统存在建模不确定性和外部环境的扰动,采用模糊逻辑系统(FLS)和一个新的扰动观测器对其进行逼近和补偿.在扰动观测器和控制器中加入了一个新的自适应参数,用来改善控制精度.基于此,本文设计了命令滤波反步控制方法,可以保证系统在所有状态下都是有界的,且跟踪误差在有限时间内小于规定的精度.仿真结果显示该方法有效,且可以满足给定的控制精度. 相似文献
18.
For compensating backlash phenomenon in servo systems, the authors propose an observer method in this paper to estimate both system states and vibration torque before controller design. First, a systematic scheme is given to obtain plant parameters, which is very important in observing system states. This is a parameter estimation principle that gives a crude estimation and computes the differences between the crude and true values. As a result, the precise value of the parameters is obtained by adding together the crude value and the difference. Then, based on the precise estimated parameters, an extended state observer (ESO) is designed to obtain feedback and feedforward signals. Consequently, robust compensation control is achieved by designing an output feedback controller, consisting of a feedback term and a feedforward term. Finally, in order to validate the proposed approach, extensive experiments are performed on a practical servo system with backlash nonlinearity. 相似文献
19.
Dynamical adaptive regulation of pulse-width-modulation (PWM) controlled power supplies is proposed using a suitable combination of average dynamical input–output linearization and the ‘backstepping’ controller design method. Nonlinear average models of dc to dc power supplies are not transformable to parametric pure nor parametric strict feedback canonical forms by means of parameter-independent state co-ordinate transformation. A more direct approach is therefore proposed for implementing the fundamental ideas related to the so called ‘non-overparametrized’ adaptive backstepping algorithm which avoids explicit transformations to the above mentioned canonical forms. Dynamical adaptive feedback controllers are developed for the regulation of the input-inductor current towards desirable constant values. The validity of the proposed approach, regarding control objectives and robustness with respect to unmodelled, yet unmatched, and bounded stochastic perturbation inputs, is tested through digital computer simulations. © 1997 by John Wiley & Sons, Ltd. 相似文献
20.
In many mechanical devices with chaotic behavior, stabilizing unstable periodic orbits (UPOs) of the system has positive effects in the lifetime and effectiveness of these devices. In this study, a new non‐parallel distributed compensation (non‐PDC) observer‐based tracking controller is presented for Takagi–Sugeno fuzzy systems to control the chaotic behavior of such systems. Asymptotic stability synthesis of the closed‐loop system is investigated using a fuzzy Lyapunov function to derive less conservative conditions than common quadratic Lyapunov function‐based approaches. To tackle the main drawback of the fuzzy Lyapunov‐based approaches, which assume some upper bounds on the derivatives of the fuzzy grade functions, we propose a new procedure by considering a constraint on the control signal. The new design conditions are given in the form of linear matrix inequalities (LMIs). The proposed control structure is applied to spinning disks in which chaos phenomena appear in lateral vibration. Simulation results are given to show the applicability of the proposed tracker to the UPO problem. 相似文献