多变量系统的内模原理——一种频域方法

本文用频城方法分析了用一般微分算子表示的多变量结构无静差系统的性质,给出了内模原理的频域形式,说明了开环系统存在结构无静差补偿器的充分必要条件,提出了设计结构无静差补偿器的方法。     

单变量系统"内模原理"的频域方法

本文用频率法讨论了单输入-单输出结构无静差系统的性质,说明了内模原理的频率表 现,给出了存在结构无静差补偿器的充要条件,提供了设计结构无静差补偿器的频率方法.     

FB-ZVZCS变换器小信号建模及补偿器设计

在研制一台功率为5 kW,开关频率为30 kHz的FB-ZVZCS变换器时,为了提高系统的控制精度和动态响应速度,利用状态空间平均法建立了该变换器的小信号模型,推导出了系统的开环传递函数.针对该系统,设计了极点-零点补偿器,并且给出了补偿器设计原则.通过仿真,给出了补偿前后的系统幅频特性图,仿真结果表明补偿后系统的快速性得到提高,稳态误差减小到零.通过实验,给出了系统输出电压的动态特性图.实验结果表明,系统的控制精度以及动态响应速度均达到指标要求.     

基于QPSO算法的传感器动态补偿方法及FPGA实现

为了解决在测试系统中由于传感器动态特性引起测试数据失真的问题,提出了一种基于量子粒子群优化算法(Quantum-Behaved Particle Swarm Optimization,QPSO)的传感器动态补偿方法;该方法依据传感器校准时的输入和输出数据运用QPSO算法得到最优补偿器模型及参数;为了将获得的最优动态补偿器运用于实时在线测量,将分布式算法引入到动态补偿器的硬件结构设计中,完成了传感器动态补偿器的高速并行FPGA实现。实验表明高速并行动态补偿器不但能够修正传感器的动态误差,而且其高速并行结构极大减少了对FPGA资源的占用率并有效的提高了系统等效吞吐率。     

有源补偿器的理论分析及 PSPICE 仿真研究

该文对有源补偿器进行了理论分析和仿真研究。研究了有源补偿器的主电路构成,工作原理及其对控制系统的要求;推导出有源补偿器主电路的PSPICE模型,并对其开环系统和闭环系统进行了仿真研究,且对仿真波形进行了分析,以验证理论研究的正确性。     

有源补偿器的理论分析及 PSHCE 仿真研究

该文对有源补偿器进行了理论分析和仿真研究。研究了有源补偿器的主电路构成,工作原理及其对控制系统的要求;推导出有源补偿器主电路的PSHCE模型,并对其开环系统和闭环系统进行了仿真研究,且对仿真波形进行了分析,以验证理论研究的正确性。     

模型参考和误差白化的传感器动态补偿算法

通过模型参考的系统辨识方法建立传感器的动态补偿器, 常用的系统辨识采用均方误差(mean square error, MSE)为评判标准. 但是, 由于测量噪声存在和补偿器的频率特性, 使得补偿器的输入/输出信号存在严重的噪声干扰, 采用MSE为评判标准的系统辨识方法, 无法得到最优的补偿器的参数. 为此, 本文研究了一种以误差白化(error whitening criterion, EWC)为评判标准, 设计传感器动态补偿器的系统辨识方法. 该方法无需事先已知系统的动态特性, 根据传感器以及参考模型对     

导前-滞后动态前馈补偿器参数整定

分析了导前－滞后动态前馈补偿器参数与系统偏差之间的关系,提出了导前－滞后补偿器参数整定的一种方法。     

广义分布参数扰动系统滑动模态控制

研究广义分布参数扰动系统的变结构及其一致收敛问题。通过引入滑动模态补偿器,得到了简约型变结构控制的设计方法。最后研究了系统 的动态品质,并指正了个别文献中存在的错误。     

传感器动态误差高速并行修正方法及其FPGA实现

为了运用动态补偿器来修正由传感器系统特性引起的动态误差,提出了一种基于改进粒子群优化(PSO)算法的动态补偿器设计方法,该方法有效的克服了PSO算法的初始值对补偿器系数的影响。为了将获得的最优动态补偿器运用于实时在线测量,将分布式算法引入到动态补偿器的硬件结构设计中,完成了传感器动态补偿器的高速并行FPGA实现。实验表明高速并行动态补偿器不但能够修正传感器的动态误差,而且其高速并行结构极大减少了对FPGA资源的占用率并有效地提高了系统等效吞吐率。     

基于神经网络的模型跟随鲁棒自适应控制

针对一类复杂非线性动力学系统,提出一种基于神经网络动态补偿的模型跟随非线 性鲁棒自适应控制策略.采用神经网络在线补偿控制器以克服系统的未建模动力学和非线性 耦合因素的影响,从而提高了模型跟随控制的动态性能和稳态精度;当系统存在模型不确定 性和外部扰动时,其输出仍能精确地跟踪期望参考模型的输出.同时给出了闭环误差系统鲁 棒稳定性的证明.应用示例表明,所提方法可保证闭环系统具有良好的跟踪性能和鲁棒性,且 算法简单,易于在线控制.     

Bounding the Parameters of Linear Systems With Input Backlash

In this note we present a two-stage procedure for deriving parameters bounds of linear systems with input backlash when the output measurement errors are bounded. First, using steady-state input-output data, parameters of the nonlinear dynamic block are tightly bounded. Then, given a suitable PRBS input sequence we evaluate tight bounds on the unmeasurable inner signal which, together with noisy output measurements are employed for bounding the parameters of the linear dynamic system     

Approximate causal output tracking for linear perturbed systems via sliding mode control

ABSTRACT

A new approach to the solution of what is termed causal output tracking problem for linear time-invariant systems in the presence of both matched and unmatched unmodelled disturbances is presented. The proposed solution is addressed through the design of a dynamic steady state estimator based on the desired system structure and an observer, considering the reference as the system output. The unmatched disturbance is estimated and used in the steady state estimator to achieve invariance, while the matched disturbance robustness is provided via sliding mode control using the super-twisting algorithm. A useful application of the presented techniques is output tracking for non-minimum phase systems; thus, the performed simulation results confirm the effectiveness of the proposed control scheme for this kind of systems.     

强抗扰恒值系统的逆LQ设计

本文着重讨论标量恒值系统在物理约束下的动态抗扰控制问题,提出一种能有效提高系 统动态抗扰能力的控制装置--瞬态补偿器;介绍了一种基于LQ最优控制逆问题的强抗扰 (指在一类外扰作用下动态误差小,且具有输出调节性质)控制器设计方法.通过对一调速系 统的实例研究,表明这种控制器可以大幅度地改善动态速降;无静差且稳定性充裕;物理实验 结果满意.     

Controllability and the theory of economic policy: a structural approach

Tinbergen's policy rule states that we must have at least as many policy instruments as the number of target variables if we wish to realize an arbitrarily fixed set of policy targets. We explore the structural characterization of the controllability of economic systems described by a set of static or dynamic equations. First, an economic system is represented as a directed graph, where the nodes stand for economic variables, while the arcs indicate the relations among these variables. Then, the main result is as follows: a static economic system is structurally controllable if and only if there exists a set of disjoint paths on the graph representation or the system which connect the set of instruments to each target. Similar graph-theoretic characterization of structural controllability is obtained for dynamic systems. Conditions for structural output controllability and structural perfect controllability are also discussed.     

Cooperative linear output regulation for networked systems by dynamic measurement output feedback

This paper investigates the cooperative linear output regulation problem of a class of heterogeneous networked systems with a common reference input but with different disturbances for individual nodes. A novel distributed control law is presented based on dynamic measurement output feedback. It is shown that the overall networked closed-loop control system is asymptotically stable and the output regulation errors asymptotically approach zero as time goes to infinity under a sufficient and necessary condition. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed control law.     

Design and Experimental Evaluation of a Discrete‐time ASPR‐based Adaptive Output Feedback Control System Using FRIT

This paper describes the design of an adaptive output feedback control system in discrete‐time, based on almost strictly positive real (ASPR)‐ness with a feedforward input. It is well‐known that an adaptive output feedback control system based on ASPR conditions can achieve asymptotic stability via a constant feedback gain. Unfortunately, most realistic systems are not ASPR because of the severe conditions. The introduction of a parallel feedforward compensator (PFC) is an efficient way to alleviate such restrictions. However, the problem remains that there exists a steady state error between the output of the augmented system and the output of the original system. The proposed scheme provides a strategy wherein the feedforward input is utilized such that the steady state error is removed. Furthermore, the fictitious reference iterative tuning (FRIT) approach is employed to determine the control parameters using one‐shot input/output experimental data directly, without prior information about the control system. This paper explains how the FRIT approach is applied in designing an adaptive output feedback control system. The effectiveness of the proposed scheme is confirmed experimentally, by using a motor application.     

A parallel algorithm for the parametric synthesis of a system for the angular stabilization of a rotating elastic beam under the action of longitudinal acceleration

A parallel algorithm for the parametric synthesis of a family of controlled linearized combined dynamic systems in which the configuration of the stability regions in the feedback parameter space depends on some slowly varying design parameters is proposed. The parametric synthesis of a system for the angular stabilization of an elastic beam rotating about a longitudinal axis under the action of a longitudinal acceleration is implemented. This kind of synthesis can substantially reduce the errors of the stabilization system and the typical regulation time in the entire range of the slow increase in the rotation velocity of the beam.     

Prescribed performance distributed consensus control for nonlinear multi-agent systems with unknown dead-zone input

In this paper, the problem of prescribed performance distributed output consensus for higher-order non-affine nonlinear multi-agent systems with unknown dead-zone input is investigated. Fuzzy logical systems are utilised to identify the unknown nonlinearities. By introducing prescribed performance, the transient and steady performance of synchronisation errors are guaranteed. Based on Lyapunov stability theory and the dynamic surface control technique, a new distributed consensus algorithm for non-affine nonlinear multi-agent systems is proposed, which ensures cooperatively uniformly ultimately boundedness of all signals in the closed-loop systems and enables the output of each follower to synchronise with the leader within predefined bounded error. Finally, simulation examples are provided to demonstrate the effectiveness of the proposed control scheme.     

REDUCED‐ORDER MODELS FOR FEEDBACK STABILIZATION OF LINEAR SYSTEMS WITH A SINGULAR PERTURBATION MODEL

The problem of output feedback stabilization of linear systems based on a reduced‐order model is addressed in this paper. New reduced‐order models are proposed for the output feedback design of linear systems with a singular perturbation model. An output feedback controller with a zero steady‐state gain matrix is proposed for stabilizing this kind of system. It is shown that with the proposed controller the reduced‐order model based feedback design can guarantee the actual closed‐loop stability for the sufficiently small perturbation parameter. This approach can overcome the difficulties in the existing design method using the so‐called zeroth‐order approximation model, whose validity is highly dependent on the value of the perturbation parameter.