负荷频率控制系统的线性自抗扰控制

本文研究负荷频率控制系统的线性自抗扰控制(linear active disturbance rejection, LADRC)方法. 考虑负荷频率控制系统的模型及结构, 本文首先通过一仿真例子分析了二阶和三阶LADRC在单区域电力系统的控制性能,指出二阶LADRC在负荷频率控制中的限制. 随后本文针对负荷频率控制中存在的发电速率约束(generation rate constraint, GRC)这一实际问题, 提出一种anti-GRC补偿方案. 该方案将汽轮机理论输出与实际输出误差作为扰动输入, 利用扩张状态观测器进行估计, 从而使LADRC能够快速补偿该误差, 达到抗积分饱和的作用. 最后, 本文将LADRC设计方法推广到具有再热汽轮机和水轮机系统以及多区域电力系统. 仿真表明LADRC是一种独立于模型的普适性控制结构, 所需整定参数少, 能够取得比PID控制更好的抗干扰性能, 可以应用到负荷频率控制系统中.     

Active disturbance rejection control: Applications in aerospace

Control of uncertain dynamical systems has been an area of active research for the past several decades and to this end, various robust control approaches have been proposed in the literature. The active disturbance rejection control (ADRC) represents one prominent approach that has been widely studied and applied for designing robust controllers in diverse areas of engineering applications. In this work, a brief review of the approach and some of its applications in aerospace are discussed. The results show that the approach possesses immense potential to offer viable solution to real life aerospace problems.     

Active disturbance rejection based load frequency control and voltage regulation in power systems

An active disturbance rejection controller (ADRC) is developed for load frequency control (LFC) and voltage regulation respectively in a power system. For LFC, the ADRC is constructed on a three area interconnected power system. The control goal is to maintain the frequency at nominal value (60Hz in North America) and keep tie line power flow at scheduled value. For voltage regulation, the ADRC is applied to a static var compensator (SVC) as a supplementary controller. It is utilized to maintain the voltages at nearby buses within the ANSI C84.1 limits (or ±5% tolerance). Particularly, an alternative ADRC with smaller controller gains than classic ADRC is originally designed on the SVC system. From power generation and transmission to its distribution, both voltage and frequency regulating systems are subject to large and small disturbances caused by sudden load changes, transmission faults, and equipment loss/malfunction etc. The simulation results and theoretical analyses demonstrate the effectiveness of the ADRCs in compensating the disturbances and achieving the control goals.     

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: some recent experimental and industrial case studies

This paper presents a summary of some recent experimental and industrial case studies of active disturbance rejection control (ADRC). ADRC is a novel disturbance estimation and rejection concept, leading to a new technology with a distinct advantage where, unlike most existing methods, disturbances, internal and external, are actively estimated and rejected. Applications of the new approach in solving industry wide bench mark problems have led to a slew of innovative solutions. The scope of the applications shown in this paper includes motion control, robotic enhanced limb rehabilitation trainings, fuel cell systems, and the two mass spring benchmark problem. Recent production line validation results obtained are also included.     

永磁同步电机自抗扰反步控制

为实现永磁同步电机的高性能控制,提出一种复合控制策略。在永磁同步电机矢量控制基础上,设计反步控制器用于电流环控制,得到同步旋转坐标系下定子电压,并能保证系统全局稳定。设计结构优化的线性自抗扰控制器用于速度环控制,提高系统抗干扰能力。采用二阶环节平滑速度指令,实现转速无超调。仿真结果表明该控制策略较传统PI控制具有转速适应范围广、无超调、抗扰动性能强等优点。     

板宽板厚多变量系统的自抗扰控制及混沌优化

针对热连轧板宽板厚双输入双输出大时滞系统的复杂性．给出了简化的数学模型．并针对该模型设计了与静态解耦补偿器串联的多变量自抗扰控制（ADRC）系统．为获得ADRC最佳参数,引入了具有全局快速搜索能力的．变尺度混沌优化方法．仿真结果表明,ADRC抗扰性和鲁棒性明显优于常规PID.     

Conditional disturbance negation based active disturbance rejection control for hypersonic vehicles

This paper presents a conditional disturbance negation (CDN) based active disturbance rejection control (ADRC) scheme for the velocity and altitude tracking control of flexible air-breathing hypersonic vehicles (FAHVs) in the presence of various uncertainties and disturbances. A pioneering CDN module is proposed to selectively compensate the total disturbances according to the characteristics of the total disturbances and the FAHV dynamics, which is aimed at canceling some detrimental disturbances while profiting from other beneficial disturbances. Firstly, model-based extended state observers are applied to estimate the total disturbances in FAHVs in an efficient way. Based on the Lyapunov theory and the estimated disturbances, a novel disturbance characterization indicator (DCI) is then designed to show whether the total disturbance harms or benefits the tracking performance in engineering practice. Then, DCI is utilized to construct the CDN module. In consequence, the CDN based FAHV tracking control is implemented in an ADRC framework, yielding the CDN based ADRC scheme. The stability analysis is conducted to show the convergence of the closed-loop system. Finally, the effectiveness and superiority of the proposed control scheme are validated by some representative simulations in various flight conditions.     

Linear active disturbance rejection control for a raceway photobioreactor

In this paper, the problem of pH regulation in photobioreactors has been addressed by using a robust Proportional–Integral controller in combination with a linear active disturbance rejection approach. This formulation is based on the Generalized Proportional–Integral (GPI) observers design to estimate online external disturbances and non-modeled dynamics. The methodology uses a model reference optimization procedure with tracking and regulatory target closed-loop transfer functions for first-order plus dead-time models. The proposed controller is validated on a full-scale Raceway photobioreactor, whose results show a significant improvement in the accuracy of pH regulation and, consequently, a positive influence on biomass production. Moreover, a classical feedforward approach has been used for comparison purposes. The performance of the robust technique is evaluated with different indexes, whose results confirm the good performance of the proposed active disturbance rejection control scheme.     

Guaranteed-cost active disturbance rejection control for uncertain systems with an integral controller

Guaranteed-cost active disturbance rejection control (ADRC) for uncertain systems is investigated in this study. Firstly, an integral action is introduced in the framework of ADRC to measure and reduce the tracking error. Then, a robust stability condition is presented, and a quadratic cost function where the tracking error is appearing explicitly is used for ADRC performance assessment. The cost bound is formulated by linear matrix inequality and optimised to obtain controller parameters. Full-dimension extended state observer is used, and thus, the proposed strategy is applicable to an uncertain system that allows relative-degree varying or right-half-plane zero. Finally, the validity of the proposed method and its advantages is demonstrated through the simulations of comparative examples and experiments on a motor speed control system.     

航天机电伺服系统的自抗扰控制

航天机电伺服系统作用是接收火箭控制系统的指令信号并带动空气舵或者喷管跟随指令信号运动,其在应用上的主要特点是负载特性变化大.传统的PID算法在航天机电伺服系统上的应用已经比较成熟,但是在空气舵或者喷管本身负载特性发生改变时,传统的PID算法的控制效果会明显下降.因此,本文建立了航天机电伺服系统柔性运动模型,并提出了将自...     

Disturbance rejection control of a fuel cell power plant in a grid-connected system

Interface of a fuel cell plant to power grid is challenging because of the high nonlinearities of the fuel cell plant and the power conditioning system (PCS). This paper focuses on the control of grid-connected solid-oxide fuel cell (SOFC) power plant that is subject to varying load and uncertain network parameters. To this end, Active Disturbance Rejection Control (ADRC) is utilized to improve the performance of the PCS consisting of a dc-dc converter and a dc-ac inverter. ADRC is used in the dc-dc converter to stabilize the dc link voltage and yield a robust performance against the nonlinearity. Used in the dc-ac inverter, ADRC eliminates the steady-state error and is insensitive to the high-frequency noise. Simulation results show that, for grid current control, ADRC achieves a more robust performance than the conventional proportional-integral (PI) controller. Moreover, the total harmonic distortions (THDs) of the output current controlled by ADRC are always below 5% in spite of the variation in the load demand and network parameters.     

Active disturbance rejection control for high pointing accuracy and rotation speed

This paper presents a design method proposed to design an active disturbance rejection control for the antenna pointing control of a large flexible satellite system. A simplified dynamics model is established using Euler-Lagrange and used to analyze the dynamic stability of the antenna system. The capturing strategy of the antenna is configured and the inner and outer loops of the active disturbance rejection control are then designed to improve pointing accuracy and rotation speed. The design of the active disturbance rejection control is verified through numerical simulation. Simulation results indicate that the proposed method can be used to achieve high pointing accuracy and rotation speed.     

推力矢量飞行器的自抗扰控制设计及控制分配

推力矢量飞行器往往需要在大功角等具有大不确定性和强非线性的区域高质量地完成飞行动作,因此,如何应对大范围不确定性是推力矢量飞行器控制设计的关键问题.另一方面,推力矢量飞行器包含多种控制输入并且不同控制输入具有不同物理特性.因此,控制输入分配也是推力矢量飞行器控制设计的关键问题.为了对付大范围的不确定性,本文引入虚拟控制量的概念,采用自抗扰控制技术实现对飞行过程中的总扰动的实时估计和补偿.进一步,考虑控制输入的物理约束条件,提出了保证虚拟控制量达到设计值并使得发动机能耗最小的控制输入分配方案.通过建立对应的优化问题,严格分析其最优解的性质并提出了有限步求解最优控制分配输入量的算法.在仿真环境下,提出的控制算法有效实现了推力矢量飞行器大功角区域的机动动作,并能应对大范围的气动参数不确定性.     

航天器姿态自抗扰控制

为抑制航天器自身结构参数变化和内外扰动对姿态控制精度和姿态稳定度的影响, 设计了航天器姿态自抗扰控制器. 自抗扰控制器(ADRC)由跟踪微分器(TD)、扩张状态观测器(ESO)和姿态反馈控制器(AFC)3部分组成.跟踪微分器负责安排姿态指令过渡过程, 并提取其微分信号. 扩张状态观测器(ESO)充分利用姿态敏感器与速率陀螺的量测信息, 可对航天器姿态及内部和外部干扰进行观测. 姿态反馈控制器则在补偿ESO估计的干扰的同时,实现航天器的姿态控制. 与已有研究相比, 扩张状态观测器采用复合量测信息对状态估计进行校正, 性能较好. 而自抗扰控制器只采用一个环路即可实现姿态控制及干扰补偿, 结构简单. 对某航天器姿态控制系统的仿真结果表明,以上自抗扰控制器是可行的.     

含有摩擦补偿的全方位移动机器人自抗扰控制

本文针对全方位移动机器人轨迹追踪中的摩擦补偿问题,提出了一种改进的非线性自抗扰控制器.首先建立了含有经典静态摩擦模型的全方位移动机器人动力学模型.其次,基于该模型设计非线性控制器和线性扩张状态观测器并给出了系统的稳定性分析.通过将模型已知项加入线性扩张状态观测器中得到摩擦力的估计值,并将估计值用于非线性控制器中摩擦补偿部分.为减小摩擦力对机器人低速运动轨迹追踪控制的影响,非线性控制器采用变增益控制器进行轨迹追踪控制.最后通过仿真结果验证本文提出控制器的有效性.     

Active disturbance rejection control to MIMO nonlinear systems with stochastic uncertainties: approximate decoupling and output-feedback stabilisation

ABSTRACT

In this paper, we apply the active disturbance rejection control, an emerging control technology, to output-feedback stabilisation for a class of uncertain multi-input multi-output nonlinear systems with vast stochastic uncertainties. Two types of extended state observers (ESO) are designed to estimate both unmeasured states and stochastic total disturbance which includes unknown system dynamics, unknown stochastic inverse dynamics, external stochastic disturbance without requiring the statistical characteristics, uncertain nonlinear interactions between subsystems, and uncertainties caused by the deviation of control parameters from their nominal values. The estimations decouple approximately the system after cancelling stochastic total disturbance in the feedback loop. As a result, we are able to design an ESO-based stabilising output-feedback and prove the practical mean square stability for the closed-loop system with constant gain ESO and the asymptotic mean square stability with time-varying gain ESO, respectively. Some numerical simulations are presented to demonstrate the effectiveness of the proposed output-feedback control scheme.     

Active disturbance rejection control for nonlinear fractional‐order systems

This paper investigates active disturbance rejection control involving the fractional‐order tracking differentiator, the fractional‐order PID controller with compensation and the fractional‐order extended state observer for nonlinear fractional‐order systems. Firstly, the fractional‐order optimal‐time control scheme is studied to propose the fractional‐order tracking differentiator by the Hamilton function and fractional‐order optimal conditions. Secondly, the linear fractional‐order extend state observer is offered to acquire the estimated value of the sum of nonlinear functions and disturbances existing in the investigated nonlinear fractional‐order plant. For the disturbance existing in the feedback output, the effect of the disturbance is discussed to choose a reasonable parameter in fractional‐order extended state observer. Thirdly, by this observed value, the nonlinear fractional‐order plant is converted into a linear fractional‐order plant by adding the compensation in the controller. With the aid of real root boundary, complex root boundary, and imaginary boot boundary, the approximate stabilizing boundary with respect to the integral and differential coefficients is determined for the given proportional coefficient, integral order and differential order. By choosing the suitable parameters, the fractional‐order active disturbance rejection control scheme can deal with the unknown nonlinear functions and disturbances. Finally, the illustrative examples are given to verify the effectiveness of fractional‐order active disturbance rejection control scheme. Copyright © 2015 John Wiley & Sons, Ltd.     

新型多旋翼作业型空中机器人自抗扰控制

针对输电线路树障清理作业任务对空中机器人平台稳定性、平动性和抗扰性的高要求,为克服传统平面配置多旋翼无人机姿态配合式位置移动的缺点,本文在全驱动多旋翼飞行器设计思想的启发下,提出并设计了一种无需姿态配合即可实现前后平移运动的非平面作业型多旋翼空中机器人.首先分别建立其姿态的运动学和动力学模型,然后采用自抗扰控制技术设计了该机器人的位置和姿态跟踪控制律.多组仿真和样机实验结果表明,本文所设计的非平面配置旋翼空中机器人在作业过程中的接触力扰动下具有良好稳定性、平动性和抗扰性.     

具有多层感知器力矩补偿的机器人自抗扰控制

本文针对机器人系统的控制特性,提出了一种基于自抗扰控制(ADRC)的关节控制算法,该算法可以克服传统控制算法中存在的如系统抗干扰能力弱,控制性能受限于建模精度,动态性能与稳态性能难以兼顾,控制律设计较为复杂等问题.针对受控系统特性给出了一套实际控制器的完整设计方法与参数整定方法,并根据控制性能指标设计优化函数完成了最优控制参数的优化,在系统参数辨识的基础上利用多层感知器(MLP)设计了对建模不确定性的补偿网络.数值仿真和实验结果均表明该算法能够实现机器人快速稳定的轨迹跟踪,具有良好的控制精度与很强的抗干扰能力,此外该算法不依赖于精确的系统模型,降低了实际设计和应用的难度,具有很好的工程应用价值.