运动平台上光电跟踪系统的自抗扰控制器设计

针对运动平台上光电跟踪系统既要有很强的抗扰动性能,又要能快速跟踪运动目标的特点,设计了稳定平台的自抗扰控制器.通过对闭环带宽的分析,改进了自抗扰控制器的结构,使闭环系统有较高的带宽.设计了扩张状态观测器对平台的扰动进行观测、补偿,并分析了系统鲁棒稳定性对扩张状态观测器的限制条件.实验结果显示,与采用PI控制相比,自抗扰控制器的稳定跟踪能力和扰动抑制能力都有一定的提高.其中,对阶跃信号的稳态跟踪误差不到PI的一半,而在2Hz附近扰动抑制比有6dB的提高.     

线性自抗扰控制参数整定鲁棒性的根轨迹分析

从极点配置和根轨迹的角度研究了二阶线性定常对象的线性自抗扰控制.提出一个新传递函数框图.基于该框图,将线性自抗扰控制的参数整定解释为闭环极点配置问题,控制器带宽、观测器带宽等参数的整定被看作开环极、零点位置的选择.建议用根轨迹法研究线性自抗扰控制的鲁棒性.通过分析根轨迹定性说明了观测器带宽可以等于控制器带宽,以及线性自抗扰控制对被控对象参数变化的鲁棒性.     

一类混沌系统的状态观测与控制

基于混沌系统运动的有界性,使得不依赖于对象模型的扩张状态观测器可用于一类混沌系统的状态观测。只要扩张状态观测器充分观测到混沌系统的状态,自抗扰控制器就可以控制混沌系统,几个混沌数值仿真表明了扩张状态观测器和自抗扰控制器可有效地用于混沌系统的观测和控制。     

基于变结构控制的二阶自抗扰控制

结合变结构控制器抗扰性能强，调节速度快和结构简单的特点，提出一种基于变结构控制器的二阶自抗扰控制器。首先，设计了系统的相轨迹和一种变结构控制律，使得系统具有更强抗扰能力和更快的调节速度。在带宽近似不变的情况下，可以通过调节参数改变系统的抗扰性和调节时间。证明了系统的稳定性，研究了变结构控制器的参数选取问题，考虑扩张状态观测器的观测误差，分析了参数选取对系统抗扰性的影响。最后，采用仿真实验测试了控制器的性能，实验结果表明，相比基于PD控制的标准自抗扰控制控制器，该控制器在调节时间、抗扰性及参数整定上均更优。     

基于线性自抗扰的开关磁阻电机调速控制研究

开关磁阻电机调速系统是复杂的非线性时变系统,负载扰动大,变量之间耦合严重,针对上述系统的性能特点提出采用线性自抗扰控制策略对系统进行控制的方法。首先为克服负载扰动变化,电机磁链呈非线性以及电流、位置等参数耦合的内外部干扰问题,设计扩张状态观测器对系统内扰和外扰进行准确估计并实时补偿。然后设计PD（比例-微分）控制器抑制系统给定与扩张状态观测器反馈的观测对象状态变量之间的跟踪误差。最后在仿真平台上对设计的控制系统进行试验并与传统PID控制方案进行对比,结果显示,对于给定的阶跃信号线性自抗扰控制器只需0.09s即可达到稳态且无超调,而PID控制器需要3s才能实现稳定跟踪。因此相比于传统PID控制,线性自抗扰控制器拥有更优的动静态性能,并且系统在外部负载扰动和内部模型参数变化的情况下也有良好的控制效果,表现出了很好的鲁棒特性。     

基于调节/观测时间的自抗扰控制器参数整定

受带宽自抗扰控制器(ADRC)参数整定方法启发,给出一种基于系统调节时间/观测时间的ADRC参数整定方法.利用调节时间与控制器带宽之间的关系,给出基于调节时间整定非线性控制器参数$k_p$及$k_d$的方法;同时,利用所定义的观测时间概念,给出一种扩张状态观测器(ESO)参数整定策略.这两种ADRC参数整定方法简化了基于带宽方法的参数整定过程,拓展了其应用范围.仿真结果表明了所提出方法的有效性.     

立方体机器人自抗扰平衡控制方法

针对立方体机器人动力学模型多变量、强耦合的问题,提出一种基于自抗扰控制的平衡控制器设计方法.引入虚拟控制量,并在控制量与输出向量之间并行地嵌入多个自抗扰控制器,从而实现对多变量系统的解耦控制,将系统的动态耦合和外部扰动视为各自通道上的自抗扰控制器的总扰动,在为期望姿态安排过渡过程基础上,设计扩张状态观测器对总扰动进行估计并实时补偿.综合采用经验试凑法和带宽法对控制器参数进行整定,对自抗扰控制器系统进行稳定控制、姿态跟踪、抗扰性和鲁棒性实验,并与PID控制系统进行定量对比分析.仿真结果表明,所设计的自抗扰控制器不仅能有效实现立方体机器人的平衡控制,而且较PID控制器具有更好的响应速度、控制精度和强鲁棒性.     

自抗扰控制器的阶次与参数的选取

本文就选择不同阶次的自抗扰控制器时,对系统的控制参数选取进行了研究.结果表明:线性时不变系统的线性自抗扰控制,可等效为一个复合控制系统,其等效反馈补偿器为一超前校正单元串联一积分器;其等效前置滤波器为一滞后校正单元串联一微分器.观测器带宽和控制器带宽的比值,决定着反馈补偿器的最大相位超前角,而频带则决定着最大相位超前角的发生位置.同时,随着自抗扰控制器阶次的增加,补偿器的最大超前校正角也增加.通过对开环系统的频域分析,本文给出了利用该补偿器的频域特性进行自抗扰控制器参数设计的一般步骤,可大幅度减少工程师的反复试验过程,方便工程师应用.     

内模控制框架下时延系统扩张状态观测器参数整定

作为一种有效的控制设计方法, 自抗扰控制研究获得了广泛关注, 然而针对自抗扰控制器的参数整定方法则相对较少. 本文针对一阶惯性加延迟系统, 将线性自抗扰控制转化为内模控制结构, 导出了其中控制器、滤波器、乘性不确定性、互补灵敏度函数的对应表达式, 随后, 利用频域鲁棒稳定性判据, 分析了自抗扰控制器核心—–扩张状态观测器的参数对闭环系统稳定性的影响. 基于该分析, 总结出一阶惯性加延迟系统扩张状态观测器的两条参数整定准则. 数值仿真结果验证了该整定准则的有效性.     

光伏三相并网系统的自抗扰控制

光伏三相并网发电系统是一个典型非线性系统,受电网和外部环境的影响,系统存在许多不确定性干扰.本文以三相光伏并网发电系统为对象,利用自抗扰控制器的扩张状态观测器,对系统模型中的不确定因素和外部干扰进行动态观测,设计一自抗扰控制器,使系统具有较好的适应能力,并对系统进行了仿真研究.结果表明所设计的控制器具有良好鲁棒性和较好的动、静态特性.     

Altitude control for flexible wing unmanned aerial vehicle based on active disturbance rejection control and feedforward compensation

For achieving the accurate trajectory tracking of the flexible wing unmanned aerial vehicle in the complicated missions, especially the vertical component, a feedforward compensation unit–based active disturbance rejection control (ADRC) is proposed. In ADRC, the internal dynamics and complicated influence of the total disturbance will be estimated and dynamically compensated by extended state observer (ESO). It puts a very high request on the observation ability of ESO with the unpredictable external disturbance, complex internal coupling influence, and the strong nonlinear characteristic of the proposed system. For this reason, by deeply analyzing the model of this system, the varying attitude influence on the altitude control will be deduced. Then, this influence will be compensated previously by a feedforward compensation unit. Through the previous compensation of the calculable part of the internal dynamics and total disturbance, the burden of ESO can be reduced largely. In this way, it improves the control effect of the ADRC with better observation precision of ESO. After that, based on the hardware‐in‐the‐loop simulation, the effectiveness of the proposed method is verified completely with the complicated flight missions. The robustness of the control effect and observation ability of ESO are also verified by the Monte Carlo simulation. At last, the results of actual flight experiment prove the advancement and practicability of the proposed ADRC method.     

结晶器多变量耦合系统的自抗扰控制

主要研究新颖实用非线性自抗扰控制算法,在结晶器多变量耦合系统中的应用.自抗扰控制主要特性是实时估计对象模型摄动和外扰的总和作用量,并在控制信号中补偿掉,实现不确定性强非线性对象的实时动态反馈线性化.结合控制对象,建立了结晶器多变量耦合自抗扰控制系统.数值仿真试验表明自抗扰耦合控制的协调性、自适应跟随性和抗干扰性优于传统的PID解耦控制.     

Active disturbance rejection control approach to stabilization of lower triangular systems with uncertainty

In this paper, we apply the active disturbance rejection control (ADRC) to stabilization for lower triangular nonlinear systems with large uncertainties. We first design an extended state observer (ESO) to estimate the state and the uncertainty, in real time, simultaneously. The constant gain and the time‐varying gain are used in ESO design separately. The uncertainty is then compensated in the feedback loop. The practical stability for the closed‐loop system with constant gain ESO and the asymptotic stability with time‐varying gain ESO are proven. The constant gain ESO can deal with larger class of nonlinear systems but causes the peaking value near the initial stage that can be reduced significantly by time‐varying gain ESO. The nature of estimation/cancelation makes the ADRC very different from high‐gain control where the high gain is used in both observer and feedback. Copyright © 2015 John Wiley & Sons, Ltd.     

Inter-sample output predictor based sampled-data ADRC supporting high precision control of VCM servo systems

Ultra high precision servo control systems usually require fast sampling rate to achieve desired digital control performance, where output sampling restrictions (such as sensor bandwidth) pose major challenges for such applications. In this paper, we propose a novel sampled-data multi-rate active disturbance rejection control (ADRC) architecture under sampling rate restrictions, where a digital extended state observer (ESO) with inter-sample output prediction structure is employed to construct inter-sample dynamics between two consecutive sampling instants, such that high frequency disturbances can be better rejected. The convergence of the estimation and the stability of the closed-loop system are analyzed based on Lyapunov function method and separation principle. The proposed control architecture is implemented on a voice coil motor (VCM) actuated micro–nano servo gantry, demonstrating significant performance improvement over existing single-rate or multi-rate ADRC methods.     

钟形振子式角速率陀螺驱动控制技术研究

钟形振子式角速率陀螺采用压电激励实现驱动模态振动。利用自抗扰控制算法对钟形振子式角速率陀螺的驱动模态进行了分析,通过构建扩张状态观测器,建立了钟形振子的自抗扰驱动控制模型,设计了钟形振子式角速率陀螺驱动模态的自抗扰控制器,使陀螺工作在调谐驱动。该设计能够补偿由加工制造误差以及环境变化等引起的陀螺参数变化,实现陀螺的固定频率谐振驱动,保持陀螺驱动轴输出信号幅值恒定。结合钟形振子式角速率陀螺实际参数,通过仿真和试验对该设计进行了验证,仿真和试验结果验证了该设计的有效性和可行性。     

Dual closed‐loop tracking control for wheeled mobile robots via active disturbance rejection control and model predictive control

A dual closed‐loop tracking control is proposed for a wheeled mobile robot based on active disturbance rejection control (ADRC) and model predictive control (MPC). In the inner loop system, the ADRC scheme with an extended state observer (ESO) is proposed to estimate and compensate external disturbances. In the outer loop system, the MPC strategy is developed to generate a desired velocity for the inner loop dynamic system subject to a diamond‐shaped input constraint. Both effectiveness and stability analysis are given for the ESO and the dual closed‐loop system, respectively. Simulation results demonstrate the performances of the proposed control scheme.     

基于神经网络的非线性扩张状态观测器

自抗扰控制方法是一种新型的非线性设计方法,在自抗扰控制器中主要存在着确定待定参数的问题;非线性扩张状态观测器是自抗扰控制器的核心,在研究非线性扩张观测器中的参数整定问题时,将神经网络的思想引入参数整定,提出了基于神经网络的非线性扩张状态观测器的设计方法,运用该方法可以对任意阶的非线性扩张状态观测器进行参数设计;大量仿真算例表明,设计出的观测器具有良好的鲁棒性,有一定工程应用参考价值.     

Active Disturbance Rejection Control for Uncertain Nonlinear Systems With Sporadic Measurements

This paper deals with the problem of active disturbance rejection control (ADRC) design for a class of uncertain nonlinear systems with sporadic measurements. A novel extended state observer (ESO) is designed in a cascade form consisting of a continuous time estimator, a continuous observation error predictor, and a reset compensator. The proposed ESO estimates not only the system state but also the total uncertainty, which may include the effects of the external perturbation, the parametric uncertainty, and the unknown nonlinear dynamics. Such a reset compensator, whose state is reset to zero whenever a new measurement arrives, is used to calibrate the predictor. Due to the cascade structure, the resulting error dynamics system is presented in a non-hybrid form, and accordingly, analyzed in a general sampled-data system framework. Based on the output of the ESO, a continuous ADRC law is then developed. The convergence of the resulting closed-loop system is proved under given conditions. Two numerical simulations demonstrate the effectiveness of the proposed control method.      

滑模控制和自抗扰控制的研究进展

本文概括了滑模控制和自抗扰控制的研究进展,进一步给出了复合控制的思想.滑模控制和自抗扰控制都有它们各自的优点,但是也都有它们各自的局限,例如:滑模控制中的抖振问题和自抗扰控制中的估计能力受限问题.复合控制结合了滑模控制和自抗扰控制的优点,并能提高闭环系统的性能.