船舶电站柴油机双脉冲H∞调速器的研究

船舶电力系统频率的稳定性主要取决于船舶电站柴油机调速系统的转速响应特性．为了抑制负荷的扰动,提高柴油机双脉冲调速器的动态精度,本文将H_∞控制理论应用于柴油机调速系统的设计,将系统的性能要求转化为标准H_∞控制问题．建立了采用双脉冲H_∞调速器的柴油机调速系统的数学模型,针对外部干扰和模型的不确定性,双脉冲H_∞调速器的设计可以归结为混合灵敏度问题．计算机仿真实验结果表明,本文设计的双脉冲H_∞调速器能在充分考虑系统模型不确定性的情况下,有效提高系统的动态精度和抑制扰动的能力,改善船舶电力系统频率的稳定性．     

船舶电站柴油机双脉冲H∞调速器的研究

船舶电力系统频率的稳定性主要取决于船舶电站柴油机调速系统的转速响应特性.为了抑制负荷的扰动, 提高柴油机双脉冲调速器的动态精度, 本文将H_∞控制理论应用于柴油机调速系统的设计,将系统的性能要求转化为标准H_∞控制问题.建立了采用双脉冲${rm H}_infty$调速器的柴油机调速系统的数学模型,针对外部干扰和模型的不确定性, 双脉冲H_∞调速器的设计可以归结为混合 灵敏度问题.计算机仿真实验结果表明, 本文设计的双脉冲H_∞调速器能在充分考虑系统模型不确定性的情况下,有效提高系统的动态 精度和抑制扰动的能力,改善船舶电力系统频率的稳定性.     

Robust control of flexible structures with stable bandpass controllers

In this paper, a control law for the active vibration control of mechanical flexible systems is considered. The proposed strategy minimizes an index and results in a stable stabilizing controller with bandpass frequency shape, due to the presence of zeros at the origin. The control authority is thus effective in a chosen band of frequency, resulting in a selective broadband control action, as opposed to narrow-band (tonal) vibration reduction. Moreover, the explicit closed-form solution of the controller is also obtained, thus avoiding numerical calculation of the solution of the Riccati equations, which can be ill-conditioned in the case of very high-order, poorly damped flexible systems. The parametrization of all the controllers is also given and a family of controllers with the above properties is deduced. The case is also obtained as a byproduct. The controller is based on a colocated actuators/sensors pair strategy and numerical simulations are presented, showing the robustness of the proposed approach even for systems with zero damping. Finally, experimental results on a skin panel of a Boeing 717 aircraft also prove the effectiveness of the proposed approach in practical complex applications, with global vibration reduction performances.     

离散双自由度鲁棒设计H∞方法研究*

以离散Ｈ∞全信息问题为基础,给出并证明了离散系统一类扰动前馈问题的设计方法,得到了控制器的参数化描述,在此基础上,研究了离散双自由度设计的Ｈ∞方法,在这一类问题中,相应标准离散Ｈ∞设计中的第二个离散代数Ｒｉｃｃａｔｉ方程不再需要求解,最后对精馏塔系统进行设计,得到了满意的结果。     

基于神经网络2自由度PID的解耦控制实现

论文将2自由度PID引入一类有强耦合带时延的多变量系统,将回路所受耦合量看成干扰量,从而将多回路系统等价成多个单回路系统;针对2自由度PID控制器参数整定困难的特点,论文利用神经网络来实现2自由度PID控制器,使控制器的两组参数能自适应调整,同时完成系统的解耦与控制工作。仿真结果表明,系统具有很好的静态和动态性能。     

一类多包传输网络控制系统的H∞鲁棒控制

研究了一类不确定时延多包传输网络控制系统的最优H∞控制问题. 针对传感器时钟驱动、控制器和执行器事件驱动的多包传输网络控制系统, 考虑不大于一个采样周期的不确定时延和有限能量的外部扰动, 提出一种基于模型的反馈控制策略, 利用Lyapunov理论推导了H∞控制律存在的充分条件, 通过求解矩阵不等式约束的优化问题得到最优H∞控制律. 数值仿真表明了所用方法的有效性.     

State-feedback H2/H-infinity controller design with D-stability constraints for stochastic systems

This paper addresses the state-feedback H2/H-infinity controller design that satisfies D-stability constraints for stochastic systems. Firstly, the concept of regional stability for stochastic systems is defined in linear matrix inequality（LMI） regions; Secondly, the characterization about stochastic D-stability is presented. This paper introduces a new technique to solve the regional stability problem for stochastic systems, which is different from the pole placement technique ever used in deterministic systems. Based on this, in the state-feedback case, mixed H2/H-infinity synthesis with D-stability constraints is discussed via LMI optimization.     

State-feedback H2/H-infinity controller design with D-stability constraints for stochastic systems

This paper addresses the state-feedback H2/H-infinity controller design that satisfies D-stability constraints for stochastic systems. Firstly, the concept of regional stability for stochastic systems is defined in linear matrix inequality(LMI) regions; Secondly, the characterization about stochastic D-stability is presented. This paper introduces a new technique to solve the regional stability problem for stochastic systems, which is different from the pole placement technique ever used in deterministic systems. Based on this, in the state-feedback case, mixed H2/H-infinity synthesis with D-stability constraints is discussed via LMI optimization.     

正规和奇异H∞控制器的统一表达式

给出了一种新的H∞控制器设计方法,通过引入设计时可选的非奇异实数阵,取消了控制器设计时对D矩阵的秩限制.适用于正规的H∞控制问题和奇异的H∞控制问题.对状态反馈等四种典型问题和输出反馈控制问题,给出了控制器存在的充分必要条件.控制器通过Riccati方程的解,用参数化方法表示.输出反馈控制器,通过解两个Riccati方程得到.讨论了控制器的相关特性.     

提高小型柴油机动力性能与经济性能的措施

小型柴油机（８．８ｋＷ）是我国农村中使用数量最多的小型动力机械。由于机械的使用、磨损以及维修保养不当等原因,致使小型柴油机技术状态变差、耗油率增高。为此,提出采取措施对小型柴油机进行改造修理。本文从理论上、工艺上及其效果等方面进行了论证。     

Comparative evaluation of nonlinear model predictive and flatness-based two-degree-of-freedom control design in view of industrial application

Two advanced nonlinear model-based control design methods – nonlinear model predictive control (NMPC) and a two-degree-of-freedom control-scheme with flatness-based feedforward control design and decentralised PI-controllers (FB-2DOF) – are compared in view of industrial application. The comparative evaluation is carried out on a setpoint-transition of the Klatt–Engell reactor model. Based on an analysis of simulation scenarios, the controllers are compared with respect to controller performance, robustness criteria, and implementation issues. Thereby, the choice of the control task and the comparison methodology are oriented on industrial practice.In the considered comparative evaluation, NMPC exhibits performance advantages when it comes to time-efficient setpoint-transitions in the nominal case, in which FB-2DOF control design is restricted by the existing input constraints. In return, robustness of stability of the FB-2DOF controller is determined only by the feedback controll part; it is therefore independent from the setpoint-transition performance – determined by the feedforward controll part – whereas the NMPC suffers from degradation of robustness properties if it is tuned for time-efficiency only. NMPC allows direct incorporation of process models and constraints, but, as it employs computationally expensive online optimisation, has to be connected to the digital control system (DCS) via some standard interface. The FB-2DOF controller in contrast can be directly implemented in a DCS, whereby the feedforward-part can be realised as an extension of an already existing feedback-part.     

H-infinity measurement-feedback control for discrete-time systems with a single measurement delay

H-infinity control problem for linear discrete-time systems with instantaneous and delayed measurements is studied. A necessary and sufficient condition for the existence of the H-infinity controller is derived by applying reorganized innovation analysis approach in Krein space. The measurement-feedback controller is designed by performing two Riccati equations. The presented approach does not require the state augmentation.     

基于H∞控制理论的2-DOF内模控制器设计及其在电力系统中的应用

给出一种基于H_∞控制理论的二自由度内模控制器设计方法.考虑了标称模型与实际模型之间存在乘性摄动时的失配性,利用适当的状态变换,将跟踪问题的控制器设计转化成一个调节问题的标准H_∞控制器设计问题,再利用H_∞输出动态反馈完成了控制器设计.以电力系统模型为例设计了一个二自由度H_∞励磁控制器,仿真结果表明了此控制器的有效性.     

Robust H∞ control design for systems with structured parameter uncertainty

In a recent paper a unification of the H₂ (LQG) and H_∞ control-design problems was obtained in terms of modified algebraic Riccati equations. In the present paper these results are extended to guarantee robust H₂ and H_∞ performance in the presence of structured real-valued parameter variiations (ΔA, ΔB, ΔC) in the state space model. For design flexibility the paper considers two distinct types of uncertainty bounds for both full- and reduced-order dynamic compensation. An important special case of these results generates H₂/H_∞ controller designs with guaranteed gain margins.     

状态滞后线性系统的H∞状态反馈控制器(英文)

利用LMI(线性矩阵不等式 )的方法, 首先给出了一般的状态滞后自治系统内稳定且具有H_∞范数界的一个充分条件. 并由此得到了一般的状态滞后系统H_∞问题有解的一个充分条件, 通过解LMI可以获得控制器的解. 最后举例说明方法的正确性.     

Outer factor ‘absorption’ for H∞ control problems

We present a constructive method for ‘absorbing’ an irrational outer factor of a plant into the ‘Q-parameter’ in the H ^∞ optimal weighted sensitivity problem for single-input/single-output distributed parameter systems, when the plant has finitely many irrational zeros on the imaginary axis. This problem could not be solved using previous results. We also extend our new results to the mixed sensitivity problem.     

带有大型挠性网状天线航天器的鲁棒H∞控制方法

针对带有大型挠性网状天线航天器存在的挠性结构不确定性问题,提出了基于比例微分(PD)结构滤波器的鲁棒H∞双层反馈控制方法,第1层采用经典的PD+结构滤波器,确保刚体部分双积分环节稳定,第2层在提取第1层标称模型后,给出通用加权函数,通过构造增广模型得到鲁棒H∞控制器.该控制器结构简单,适合工程应用.通过仿真表明,本方法相对于传统PID+结构滤波器方法能够快速稳定三轴姿态;当结构参数变化较大且三轴姿态偏置为动态时变时,有可能导致传统方法失稳,而本方法具有较强的鲁棒适应性,仍能完成航天器天线的指向任务.