参数不确定非线性系统的鲁棒镇定与鲁棒跟踪设计

针对参数不确定非线性系统的鲁棒镇定和鲁棒跟踪问题，提出了一种基于Lyapunov稳定性理论的非线性动态鲁棒控制器设计方法，将设计过程分为两步，第一步是针对标系统设计使其实现控制目标的控制器，第二步是在第一步的基础上，进一步设计控制器抑制由于不确定性因素所产生的原系统与标称系统之间的偏差，其优点是在设计的第一步可以直接利用基于精确数学模型建立的非线性控制系统设计方法，数值仿真验证了设计方法的正确性。     

Small signal stability analysis and optimal control of a wind turbine with doubly fed induction generator

A novel method using particle swarm optimisation (PSO) is proposed for optimising parameters of controllers of a wind turbine (WT) with doubly fed induction generator (DFIG). The PSO algorithm is employed in the proposed parameter tuning method to search for the optimal parameters of controllers and achieve the optimal coordinated control of multiple controllers of WT system. The implementation of the algorithm for optimising the controllers' parameters is described in detail. In the analysis, the generic dynamic model of WT with DFIG and its associated controllers is presented, and the small signal stability model is derived; based on this, an eigenvalue-based objective function is utilised in the PSO-based optimisation algorithm to optimise the controllers' parameters. With the optimised controller parameters, the system stability is improved under both small and large disturbances. Furthermore, the fault ride-through capability of the WT with DFIG can be improved using the optimised controller. Simulations are performed to illustrate the control performance.     

Adaptive backstepping motion control of induction motor drives

Abstract

In this paper, an adaptive backstepping controller is proposed for position tracking of a mechanical system driven by an induction motor. The mechanical system is a single link fixed on the shaft of the induction motor such as a single‐link robot. The backstepping methodology provides a simpler design procedure for an adaptive control scheme and provides a method to define the sliding surface if the robust slidingmode control is applied. Thus, the backstepping control can be easily extended to work as an adaptive sliding‐mode controller. The presented position control system is shown to be stable and robust to parameter variations and external disturbances. The effectiveness of the proposed controllers is demonstrated in experiments.     

A robust hybrid fuzzy–simulated annealing–intelligent water drops approach for tuning a distribution static compensator nonlinear controller in a distribution system

This article presents a novel hybrid optimization approach for a nonlinear controller of a distribution static compensator (DSTATCOM). The DSTATCOM is connected to a distribution system with the distributed generation units. The nonlinear control is based on partial feedback linearization. Two proportional-integral-derivative (PID) controllers regulate the voltage and track the output in this control system. In the conventional scheme, the trial-and-error method is used to determine the PID controller coefficients. This article uses a combination of a fuzzy system, simulated annealing (SA) and intelligent water drops (IWD) algorithms to optimize the parameters of the controllers. The obtained results reveal that the response of the optimized controlled system is effectively improved by finding a high-quality solution. The results confirm that using the tuning method based on the fuzzy-SA-IWD can significantly decrease the settling and rising times, the maximum overshoot and the steady-state error of the voltage step response of the DSTATCOM. The proposed hybrid tuning method for the partial feedback linearizing (PFL) controller achieved better regulation of the direct current voltage for the capacitor within the DSTATCOM. Furthermore, in the event of a fault the proposed controller tuned by the fuzzy-SA-IWD method showed better performance than the conventional controller or the PFL controller without optimization by the fuzzy-SA-IWD method with regard to both fault duration and clearing times.     

基于LMI的鲁棒H∞控制建筑结构振动

针对多层框架结构系统,提出一种基于线性矩阵不等式(Linear Matrix Inequalities, LMI)的鲁棒H∞控制方法。为了使控制方法能相对简单,便用工程应用,将工程中常用的二次型性能指标结合于鲁棒H∞控制系统的分析中,并应用线性矩阵不等式减小求解的复杂度。以一个三层框架结构模型为例进行了仿真,并与传统H∞控制方法进行对比,仿真结果初步表明该方法在保证较好控制效果的条件下具有更强鲁棒性。     

建筑结构基于LMI的鲁棒非脆弱H∞控制

考虑一维地震动作用和结构参数不确定性影响,提出一种基于线性矩阵不等式(Linear Matrix Inequalities, LMI)的鲁棒非脆弱H_∞控制方法。引入工程中常用的二次型最优指标,并应用线性矩阵不等式减小求解的复杂度,使得控制器的性能指标容易衡量,设计相对简单,便于工程应用。以一个三层剪切型结构模型为例进行数值分析,并与传统H_∞控制方法进行对比,仿真结果初步表明:1) 所提方法具有很好的控制效果和鲁棒性;2) 合理地计算结构参数值,可使控制系统在具有最优反应品质的前提下,获得相对更好的鲁棒性和非脆弱性。     

合肥光源真空控制系统

合肥光源（HLS）是第二代专用同步辐射光源，由200MeV直线加速器、输运线和800MeV电子储存环组成。真空控制系统是基于EPICS（Experimental Physicsand Industrial Control System）的分布式控制系统，3台10C分别控制储存环上的7台Varian真空规控制器、直线加速器上的15台溅射离子泵电源控制器和输运线上16台溅射离子泵的电源控制器。采用Channel Arciver实现了储存环真空度及直线输运线溅射离子泵离子流数据的采集、存档及检索的功能。利用开发的CGI程序，改善了数据检索的性能，并对合肥光源储存环真空管道的束流清洗过程进行了分析。     

Robust controllers design and efficiency analysis for a brushless servo system

Abstract

This paper investigates the design of robust controllers for a class of ac servo drives, the brushless servo motor drive, and presents the efficiency and power factor analysis of the drive system. Robust PI, H ², and H ⁸ control techniques are applied to the design of servo controllers. A fully digital control system is constructed to experimentally verify the controller performance. The steady‐state characteristics of the servo drive are derived and are measured on‐line by a microcomputer‐based efficiency measurement system. The theoretical development is validated by the experimental work.     

Using the blender game engine for real-time emulation of production devices

This paper describes the principles, architecture and design details for using the Blender Game Engine in real-time production device emulation. An emulation system for a real material transport and handling production installation was implemented based on this. A prototype of a distributed production control system was run on top of the device emulation system to evaluate feasibility. A cardinal architectural principle is the clear distinction between production controllers and production devices. This principle, applicable through flexible communication middleware, enables the implementation of portable production controllers that execute transparently on either the emulated or the real production system. Production system engineers may take advantage of this approach to develop and gain confidence in complex production control solutions.     

Optimisation-based control coordination of PSSs and FACTS devices for optimal oscillations damping in multi-machine power system

An optimal procedure for designing co-ordinated controllers of power system stabiliser and flexible ac transmission system devices is developed for achieving and enhancing small-disturbance stability in multi-machine power systems. A constrained optimisation approach is applied for minimising an objective function formed from selected eigenvalues of the power systems state matrix. The eigenvalue-eigenvector equations associated with the selected modes form a set of equality constraints in the optimisation. There is no need for any standard eigenvalue calculation routines, and the use of sparse Jacobian matrix in the case of large system for forming the eigenvalue-eigenvector equations leads to the sparsity formulation. Inequality constraints include those for imposing bounds on the controller parameters. Constraints which guarantee that the modes are distinct ones are derived and incorporated in the control coordination formulation using the property that eigenvectors associated with distinct modes are linearly independent. The robustness of the controllers is achieved very directly through extending the sets of equality constraints and inequality constraints in relation to selected eigenvalues and eigenvectors associated with the state matrices of power systems with loading conditions and/or network configurations different from that of the base case. Simulation results of a multi-machine power system confirm that the procedure is effective in designing controllers that guarantee and enhance the power system small-disturbance stability.     

Dynamic control of the permanent magnet-assisted reluctance synchronous machine

A digital signal processor-based control system for the permanent magnet-assisted reluctance synchronous machine, with the emphasis on dynamic performance, is proposed. A classical design approach is used to design the current and speed controllers for the machine. The stator current of the machine is controlled in such a way that the current angle in the dq synchronous reference frame is constant. The load-torque is estimated using a state space observer and compensation current based on the estimated load is used to improve the dynamic performance of the drive. The control system design is machine specific as it relies on data from finite-element analysis. Simulated and measured results on a 110-kW power level show that the resulting control system is stable and robust with good dynamic performance     

A comparison of multirate robust track-following control synthesis techniques for dual-stage and multisensing servo systems in hard disk drives

This paper presents the system modeling, design, and analysis of multirate robust track-following controllers for a dual-stage servo system with a microelectromechanical systems (MEMS) microactuator (MA) and an instrumented suspension. A generalized model is constructed which includes a nominal plant, disturbances, uncertainties, and multirate sensing and control. Two major categories of controller design methodologies are considered. The first includes synthesis methodologies that are based on single-input single-output (SISO) design techniques, and includes the sensitivity decoupling (SD) and the PQ methods. In this case, a high sampling-rate inner loop damping control is first implemented using the auxiliary sensor signals. Subsequently, a low-rate outer loop controller is designed for the damped plant using either the SD or PQ design methods. The second category of design methodologies includes those based on multirate, multi-input multi-output (MIMO) design techniques, including mixed H/sub 2//H/sub /spl infin//, mixed H/sub 2///spl mu/, and robust H/sub 2/ synthesis. In this case, a set of controllers, which is periodically time-varying due to multirateness, is designed by explicitly considering plant uncertainty and hence robust stability. Comparisons are made between all the design techniques in terms of nominal H/sub 2/ performance, robust stability, and robust performance between these controllers, when the feedback controller is closed around the full order, perturbed plant. The advantages and disadvantages of each of these methods are discussed, as well as guidelines for their practical implementation.     

A set of decentralized PID controllers for an n – link robot manipulator

A class of stabilizing decentralized proportional integral derivative (PID) controllers for an n-link robot manipulator system is proposed. The range of decentralized PID controller parameters for an n-link robot manipulator is obtained using Kharitonov theorem and stability boundary equations. Basically, the proposed design technique is based on the gain-phase margin tester and Kharitonov??s theorem that synthesizes a set of PID controllers for the linear model while nonlinear interaction terms involve in system dynamics are treated as zero. The stability analysis of the composite system with the designed set of decentralized PID controllers is investigated by incorporating bounding parameters of interconnection terms in LMI formulation. From the range of controller gains obtained by the proposed method, a genetic algorithm is adopted to get an optimal controller gains so that the tracking error is minimum. Simulation results are shown to demonstrate the applicability of the proposed control scheme for solution of fixed as well as time-varying trajectory tracking control problems.     

Mathematical modelling and control of human skeletal dynamics

Neuroprostheses are devices that may restore motor function to the paralysed by artificially activating skeletal muscle. The design of controllers for these devices is greatly facilitated by mathematical models for the system to be controlled. However, human muscle and skeletal dynamics possess a variety of properties, making them difficult both to model and to control. Recently developed mathematical models of human muscle and musculoskeletal dynamics are outlined in this article. The insight provided by such models into system behaviours, their use in designing neuroprosthetic control strategies and an animation tool used to visualise the effectiveness of controllers for sit-to-stand transfer in paraplegic individuals are presented     

基于LMI的结构主动控制系统故障诊断与隔离设计

基于H∞鲁棒控制原理,提出了结构主动控制系统故障检测器的设计方法,形成了结构主动控制系统的故障诊断与隔离技术(fault detection and isolation,FDI)。首先根据H∞控制目标提出了FDI系统的模型,将故障信号的检测问题转化为一个鲁棒控制问题,应用线性矩阵不等式(linear matrix inequality,LMI)算法解出H∞最优控制器,即故障检测器。通过一个三层框架结构的数值算例验证了设计的有效性。该研究工作为结构主动控制系统的健康检测提供了参考,为进一步进行容错控制的研究奠定了基础。     

新型陶瓷快速成型装置数控系统的研究

基于GT400运动控制器的开放式体系结构的数控系统软硬件平台及其关键技术,研究陶瓷零件快速成型设备数控系统对于缩短陶瓷零件的制造周期以及提高企业的生产效率所具有的重要意义.阐述了陶瓷零件快速成型机的新工艺方法和特点,对新型陶瓷零件快速成型机机械系统及其控制要求作了详细分析,着重介绍了陶瓷零件快速成型机控制系统的硬件设计及自顶向下的软件设计.利用Visual C++6.0开发工具和GT系列运动控制器自带的DLL动态链接库开发了操作方便、运行稳定、加工精度高的开放式陶瓷快速成型装置数控系统.控制系统能够很好地满足系统开放性的要求及产品自动化生产的要求,提高了经济效益.     

Adaptive controller design for a synchronous reluctance motor drive system with direct torque control

The design and implementation of adaptive controllers for a sensorless synchronous reluctance drive system with direct torque control is proposed. Two adaptive control algorithms, which include adaptive backstepping control and model-reference adaptive control, are proposed to improve the performance of a sensorless direct torque control synchronous reluctance motor drive system. A digital signal processor, TMS320-C30, is used to execute the rotor position estimating technique and the adaptive control algorithms. The system shows good transient responses, good load disturbance responses and good tracking responses. Several experimental results validate the theoretical analysis. The advanced controller design for a sensorless synchronous reluctance motor drive with direct torque control is proposed.     

空压机智能系统研究

为了满足矿山的生产要求和实现空压机的节能降耗,以上位机组态软件为开发平台,采用可编程序控制器PLC为控制核心,设计了一套集远程控制和故障诊断预警于一身的空压机智能控制系统。对空压机的智能联控、故障诊断以及故障报警死区等关键性技术进行了研究和开发设计,实现了对空压机的远程集中控制、故障报警和设备故障诊断功能,提高了矿山生产的安全性和可靠性,降低了能源和成本消耗。     

新型冷库冷风机控制器

介绍一种新型冷风机控制器。该控制器不但能够实现对电子膨胀阀与除霜等主要方面的控制,而且附带各种传感器的接口,能够通过计算机网络实现实时远程监控,在第一时间发现故障,便于维护修理,同时节能效果显著。它的出现在某种程度上实现了机电一体化,并向着整体联合控制的方向发展。