热轧带钢层流冷却系统的前馈-反馈控制及其优化

以热轧层流冷却系统为研究对象,对如何提高带钢卷取温度控制精度进行了研究;在带钢冷却模型的基础上,对预设定模块进行了前馈补偿;考虑模型的不确定性和大时滞特性,采用模糊Smith预估器提高了反馈控制的精度;结果证明所采用的这些措施大大提高了卷取温度的控制精度。     

基于解耦控制的同步传动技术的应用研究

对龙门移动式镗铣床同步传动不一致性问题进行研究,用两台直线电机作为龙门柱纵向进给的传动机构,分析了扰动与输出之间存在的耦合,设计出一种解耦控制器,并用龙门框架不平行时所产生的应力变化进行补偿。仿真结果表明,系统性能良好,并能快速实现同步运行。     

稳健二进神经网络的几何训练

在二进神经网络的规划划分训练方法基础上,针对稳键二进神经网络稳健神经元的特点,讨论了稳健分类超平面的几何构造方法,并提出了相应的训练算法,包括隐层神经元的几何训练和输出神经无的进化训练。实验表明,该算法对复杂Boole函数的稳健二进神经网络的实现是有效且可行的。     

Towards the Optimal Learning Rate for Backpropagation

A backpropagation learning algorithm for feedforward neural networks withan adaptive learning rate is derived. The algorithm is based uponminimising the instantaneous output error and does not include anysimplifications encountered in the corresponding Least Mean Square (LMS)algorithms for linear adaptive filters. The backpropagation algorithmwith an adaptive learning rate, which is derived based upon the Taylorseries expansion of the instantaneous output error, is shown to exhibitbehaviour similar to that of the Normalised LMS (NLMS) algorithm. Indeed,the derived optimal adaptive learning rate of a neural network trainedby backpropagation degenerates to the learning rate of the NLMS for a linear activation function of a neuron. By continuity, the optimal adaptive learning rate for neural networks imposes additional stabilisationeffects to the traditional backpropagation learning algorithm.     

H∞ ALMOST DISTURBANCE DECOUPLING FOR MIMO BILINEAR SYSTEMS

The H_∞ almost disturbance decoupling problem is considered. In this paper, a nonlinear design is proposed to find a state feedback controller for bilinear systems. The closed‐loop system is internally stable and achieves disturbance attenuation in nonlinear H_∞ sense. We defined a special form of Lyapunov function, which is constructed in terms of one or a set of positive definite constant matrices. If, except of the origin of system, the corresponding polynomial of the positive definite matrix (or several polynomials relevant to the positive definite constant matrices) has (have) no zero on a given subset of state space, then we can construct a controller to solve our problem. It is found that the controller structure could be complicated, but is feasible in computation and may require optimization technique to search the solution. We consider both SIMO and MIMO cases with illustrated examples.     

一种前馈广义预测控制算法的研究及其仿真

研究了原油常压蒸馏塔的前馈广义预测控制算法 (GPC) ,克服了可测扰动对系统的作用。建立了以进料温度为可测扰动的常压塔常一线温度控制的CARIMA模型 ,实现了前馈GPC算法的仿真 ,验证了该算法对具有可测扰动的过程系统具有良好的控制作用 ,使系统具有良好的鲁棒性。     

中厚板水幕分组冷却的最优前馈控制算法

针对中厚板水幕分组冷却系统的最优前馈控制算法进行了研究。由该算法确定水幕的开幕数、流量及水幕的排列方式 ,从而对水幕入口温度的波动进行补偿。     

考虑前馈作用的BTT导弹自动驾驶仪设计方法研究

针对BTT导弹自动驾驶仪的设计要求,文章提出了一种考虑前馈作用的导弹自动驾驶仪控制器设计方法。基于该型导弹三通道弹体数学模型,建立了自动驾驶仪控制系统数学模型。应用增益技术和递推设计方法,并基于过载稳定跟踪控制的设计要求,提出了一种全局非线性稳定控制策略,设计了连续的非线性自动驾驶仪,解决了该导弹俯仰通道的前馈问题;对于偏航通道,通过设计三通道协调控制律,将有前馈的自动驾驶仪设计问题转化为无前馈的设计问题;同时也利用滑模变结构控制原理解算出了横滚通道的舵偏角指令。数字仿真结果表明,所设计的自动驾驶仪控制系统可有效克服前馈问题所产生的稳态误差以及不确定性因素的影响,同时也提高了跟踪精度,并具有良好的动态特性和稳态品质。     

Disturbance decoupling of switched linear systems

In this paper, we consider disturbance decoupling problems for switched linear systems. We will provide necessary and sufficient conditions for three different versions of disturbance decoupling, which differ based on which signals are considered to be the disturbance. In the first version, the exogenous input is considered as the disturbance, in the second, the switching signal and in the third both of them are considered as disturbances. All three versions of disturbance decoupling have direct counterparts for linear parameter-varying (LPV) systems, while the latter instance of the problem is relevant for disturbance decoupling of piecewise linear systems, as we will show. The solutions of the three disturbance decoupling problems will be based on geometric control theory for switched linear systems and will entail both mode-dependent and mode-independent static state feedback.     

基于自适应技术的低频噪声控制研究

针对电力变压器低频噪声问题,探讨有源噪声控制的设计方法,提出基于参数化线性滤波器优化的有源噪声前馈控制算法,同时给出了信号检测传感器的布放方案,并通过误差传感器展示噪声消除的效果.该有源噪声控制器能实现电力系统设备的噪声自动检测,并根据设备噪声的具体情况实施控制以达到降噪的目的.以220kV电力变压器有源噪声控制为例,实验结果证明,利用有源噪声控制技术实现对电力系统设备低频噪声的控制是一种有效的途径.