采用干扰–观测器控制的移动智能体系统之一致性(英文)

本文研究了具有非线性耦合与外部干扰的移动多智能体系统的一致性问题.假设系统不存在外部干扰的情况,设计了一个牵引控制使得移动智能体系统达到一个期望值.假设系统存在一个外部干扰,应用干扰–观测器控制,使得系统中的所有智能体可以渐近达到一致.通过分析具有固定拓扑和时变拓扑的移动多智能体动态系统,得到了许多基于抗干扰观测器的系统收敛性条件.最后应用仿真实例说明了结论的有效性.

基于干扰观测器的电子节气门连续滑模控制

电子节气门是一种典型的非线性系统,采用一般的滑模控制会产生不可消除的抖振,影响控制效果。为解决这一问题,提出基于干扰观测器的滑模控制,其中干扰观测器前馈补偿观测到的干扰,滑模控制器消除其他干扰,因此很大程度上降低了滑模控制器的切换增益值,达到削弱抖振的目的。通过MATLAB/Simulink平台的仿真试验,证明这种控制方法对消除抖振的可行性和有效性。

基于多变量干扰观测器-控制器综合的再入姿态控制

针对高超声速飞行器的再入姿态控制问题,分别在全状态反馈和输出反馈的框架内,研究基于多变量干扰观测器-控制器综合的再入姿态控制策略,实现系统在不确定及外界干扰综合影响下对给定制导指令的高精度快速跟踪研究,并在Matlab/Simulink中进行仿真校验.通过仿真结果可以得出,基于输出反馈的干扰观测器-控制器对干扰有较好的响应,可以在遇到干扰时快速跟踪上期望值并保持稳定.

具有多源干扰的线性系统固定时间抗干扰控制

本文研究了具有多源干扰的线性系统的固定时间抗干扰问题,提出一种基于干扰观测器的固定时间控制策略。该策略不仅使闭环系统达到全局固定时间稳定,而且提高了抗干扰控制的性能。最后,通过数值算例验证了所提出控制策略的可行性。

非线性系统的有限时间精细抗干扰控制

本文研究一类具有多源干扰的非线性系统在有限时间条件下抗干扰问题,提出有限时间精细抗干扰控制方案。通过设计非线性干扰观测器,解决系统中含有的不确定性非线性项,同时保证复合系统全局有限时间稳定。最后,通过一个数值仿真实例验证了本文所设计的控制方案是可行的。

一类带有多源干扰的离散时间随机系统的抗干扰控制

考虑了一类带有多源干扰的离散时间随机系统的抗干扰控制问题,其中干扰包括非线性和一系列随机变量.通过设计干扰观测器来估计干扰,并提出基于干扰观测器的干扰抵消方法以保证复合系统达到满意的动态性能.最后,通过仿真算例验证了所提方案的有效性.

自主空中加油输油阶段无人机建模与控制

针对自主空中加油输油阶段无人机位置保持控制问题,将无人机分为飞机本体和油箱两部分,利用变质量系统理论建立了无人机非线性方程,解决了常规模型无法反映出无人机重量、重心变化的问题。控制律设计方面,通过将变化的油箱转化为外界干扰,提出了基于干扰观测器控制(disturbance observer based control,DOBC)的复合控制结构。复合控制器由位置保持控制器和干扰观测器组成,位置保持控制器采用带积分的线性二次型方法,干扰观测器由比例积分观测器和补偿单元构成,并证明了复合控制器的稳定性。仿真结果表明,将该控制器应用于某型高空无人机非线性模型,可有效减小输油过程带来的影响,实现了输油阶段的位置保持控制。

一类非线性离散系统的复合DOBC和饱和控制

研究了一类带有干扰的非线性离散系统的抗干扰控制问题.针对外部干扰,设计了干扰观测器进行估计;针对系统中的饱和项,设计饱和控制器来消除饱和的影响.在此基础上,提出了基于干扰观测器的控制(DOBC)和饱和的复合控制策略,解决了一类非线性离散系统抗干扰控制问题.

空间飞行器抓捕非合作目标后的复合控制

随着空间技术的不断发展,空间飞行器抓取非合作目标的稳定控制技术变得日益重要。基于拉格朗日动力学原则对空间飞行器进行动力学建模,考虑了非合作目标的未知参数、空间飞行器模型的不确定性及存在外部干扰的情况,理论分析了自适应控制及基于非线性干扰观测控制的可行性,并对比了二者的优缺点。在此基础上提出了一种可以在线精确估计非合作目标未知参数的复合控制方法,并进行了仿真验证。仿真结果表明,所提方法能够将所有参数的估计误差限制在很小的范围内,相对于自适应控制方法有了显著改善。

一类随机系统基于干扰观测器的抗干扰控制

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.

基于改进最速TD和DOBC的光储并网功率平滑策略

为提高光储系统并网功率的稳定性,提出基于改进最速跟踪微分器(TD)算法和干扰观测控制(DOBC)原理的储能系统平滑策略。首先,采用相位补偿的最速TD算法实现并网功率跟踪;其次,设计了一阶干扰观测器以求出储能系统的目标输出功率;最后,对储能系统进行约束以避免电池过充、过放及出力骤变等情况。仿真和真实微网系统实验表明,相较于传统策略,所提策略具有跟踪响应及时、平滑效果优越、储能功率波动小等优点,具有工程应用价值。

具有多干扰的非线性时变时滞关联系统的复合分层抗干扰控制

针对一类带有多干扰的非线性时变时滞关联系统,考虑了复合抗干扰控制器设计问题.复合抗干扰控制器的设计主要结合了基于干扰观测器的控制方法(Disturbance observer based control,DOBC)和H_∞控制方法.系统受到的干扰可以分为两类:第一类干扰由外部系统描述,并且与控制输入在同一通道;第二类干扰假定满足有界H_2范数.设计干扰观测器估计第一类干扰,并利用干扰估计值进行前馈补偿;利用H_∞控制方法对第二类干扰进行衰减.利用Lyapunov函数理论分析了闭环系统的稳定性,并以线性矩阵不等式的形式给出了可解的时滞依赖条件.最后,利用数值仿真验证了所提方法的有效性.

Disturbance Observer Based Control for Four Wheel Steering Vehicles With Model Reference

This paper presents a disturbance observer based control strategy for four wheel steering systems in order to improve vehicle handling stability. By combination of feedforward control and feedback control, the front and rear wheel steering angles are controlled simultaneously to follow both the desired sideslip angle and the yaw rate of the reference vehicle model.A nonlinear three degree-of-freedom four wheel steering vehicle model containing lateral, yaw and roll motions is built up, which also takes the dynamic effects of crosswind into consideration.The disturbance observer based control method is provided to cope with ignored nonlinear dynamics and to handle exogenous disturbances. Finally, a simulation experiment is carried out,which shows that the proposed four wheel steering vehicle can guarantee handling stability and present strong robustness against external disturbances.

Fast integrated guidance and control with global convergence

A global fast convergent integrated guidance and control design approach is proposed. A disturbance observer is utilized to estimate the uncertainties of integrated guidance and control model in finite time. According to the multiple sliding-mode surface control, the independent nonsingular terminal sliding functions are presented in each step, and all the sliding-mode surfaces run parallel. These presented sliding-mode surfaces keep zero value from a certain time, and the system states converge quickly in sliding phase. Therefore, the system response speed is increased. The proposed method offers the global convergent time analytically, which is useful to optimize the transient performance of system. Simulation results are used to verify the proposed method.

Nonlinear cascade control of single-rod pneumatic actuator based on an extended disturbance observer

Precise position tracking control of the single-rod pneumatic actuator is considered and a nonlinear cascade controller is developed.The proposed controller comprises an extended disturbance observer(EDOB)and a nonlinear robust control law synthesized by the backstepping method.The EDOB is designed to estimate not only the influence of disturbances but also the parameter uncertainties.With the use of parameter and disturbance estimates,the nonlinear cascade controller,which consists of an outer position tracking loop and an inner load pressure loop,is further designed to attenuate the effects of parameter and disturbance estimation errors.The stability of the closed-loop system is proven by means of Lyapunov theory.Extensive comparative experimental results obtained verify the effectiveness of the proposed nonlinear cascade controller and its performance robustness to parameter and external disturbance variations in practical implementation.

随机多源干扰系统的复合DOBC和容错控制

针对一类带有多源干扰和常值故障的随机系统,研究其抗干扰和故障诊断问题.多源干扰包括由外源系统生成的部分信息已知的干扰和白噪声干扰两类.第1类干扰包含状态和干扰耦合,不仅可以代表一类部分信息已知的干扰,还可以代表一类随机干扰,且耦合增加了系统的复杂性,导致必然等价原则的无效.为了解决这个问题,提出复合极点配置和线性矩阵不等式(LMI)方法相结合的策略.首先,设计随机干扰观测器来估计第1类干扰;其次,设计随机故障诊断观测器来估计系统故障.基于此,结合容错控制和随机控制,提出基于观测器的复合容错控制策略,在满足一定条件下,该策略可以保证复合系统满足依均方渐近有界.最后,通过仿真验证所提出策略的正确性与有效性.

Improved Disturbance Observer (DOB) Based Advanced Feedback Control for Optimal Operation of a Mineral Grinding Process

Advanced feedback control for optimal operation of mineral grinding process is usually based on the model predictive control (MPC) dynamic optimization. Since the MPC does not handle disturbances directly by controller design, it cannot achieve satisfactory effects in controlling complex grinding processes in the presence of strong disturbances and large uncertainties. In this paper, an improved disturbance observer (DOB) based MPC advanced feedback control is proposed to control the multivariable grinding operation. The improved DOB is based on the optimal achievable H 2 performance and can deal with disturbance observation for the nonminimum-phase delay systems. In this DOB-MPC advanced feedback control, the higher-level optimizer computes the optimal operation points by maximize the profit function and passes them to the MPC level. The MPC acts as a presetting controller and is employed to generate proper pre-setpoint for the lower-level basic feedback control system. The DOB acts as a compensator and improves the operation performance by dynamically compensating the setpoints for the basic control system according to the observed various disturbances and plant uncertainties. Several simulations are performed to demonstrate the proposed control method for grinding process operation.

Robust Anti⁃swing Control for Unmanned Helicopter Slung⁃Load System with Prescribed Performance

A robust anti-swing control method based on the error transformation function is proposed,and the problem is handled for the unmanned helicopter slung-load system(HSLS)deviating from the equilibrium state due to the disturbances in the lifting process.First,the nonlinear model of unmanned HSLS is established.Second,the errors of swing angles are constructed by using the two ideal swing angle values and the actual swing angle values for the unmanned HSLS under flat flight,and the error transformation functions are investigated to guarantee that the errors of swing angles satisfy the prescribed performance.Third,the nonlinear disturbance observers are introduced to estimate the bounded disturbances,and the robust controllers of the unmanned HSLS,the velocity and the attitude subsystems are designed based on the prescribed performance method,the output of disturbance observer and the sliding mode backstepping strategy,respectively.Fourth,the Lyapunov function is developed to prove the stability of the closed-loop system.Finally,the simulation studies are shown to demonstrate the effectiveness of the control strategy.

Nonsingular Fast Terminal Sliding Mode Control Based on Nonlinear Disturbance Observer for a Quadrotor

Given external disturbances and system uncertainties,a nonsingular fast terminal sliding mode control(NFTSMC)method integrated a nonlinear disturbance observer(NDO)is put forward for quadrotor aircraft.First,a NDO is proposed to estimate the actual values of uncertainties and disturbances.Second,the NFTSM controller based on the reaching law is designed for the attitude subsystem(inner loop),and the control strategy can ensure Euler angles’fast convergence and stability of the attitude subsystem.Moreover,the NFTSMC strategy combined with backstepping is proposed for the position subsystem(outer loop),which can ensure subsystem tracking performance.Finally,comparative simulations show the trajectory tracking performance of the proposed method is superior to that of the traditional sliding mode control(SMC)and the SM integral backstepping control under uncertainties and disturbances.

Disturbance rejection control for Raymond mill grinding system based on disturbance observer

In the Raymond mill grinding processes,high-accuracy control for the current of Raymond mill is vital to enhance the product quality and production efficiency as well as cut down the consumption of spare parts.However,strong external disturbances,such as variations of ore hardness and ore size,always exist.It is not easy to make the current of Raymond mill constant due to these strong disturbances.Several control strategies have been proposed to control the grinding processes.However,most of them(such as PID and MPC)reject disturbances merely through feedback regulation and do not deal with the disturbances directly,which may lead to poor control performance when strong disturbances occur.To improve disturbance rejection performance,a control scheme based on PI and disturbance observer is proposed in this work.The scheme combines a feedforward compensation part based on disturbance observer and a feedback regulation part using PI.The test results illustrate that the proposed method can obtain remarkable superiority in disturbance rejection compared with PI method in the Raymond mill grinding processes.