基于神经网络可调模型的直接转矩控制系统速度辩识

基于无速度传感器辨识精度和动态性能的提高,在传统的模型参考自适应(MRAS)速度辨识模型的基础上,参考模型采用转子磁链电压模型。应用神经网络理论,对其可调模型进行了改进。并在无速度传感器直接转矩控制系统中对该速度辨识模型进行了研究,仿真结果验证了该速度辨识模型具有满意的辨识精度和动态性能。     

三流方坯连铸机自动化系统

本文介绍了某炼钢厂三流方坯连铸机自动控制系统的技术方案，着重描述了拉矫辊和结晶器振动变频调速系统和铸流跟踪系统，也介绍了西门子S7-300PLC与MM440变频器基于PROFIBUS-DP现场总线的数据通讯和各PLC之间以及PLC与WINCC之间通过MPI网络进行数据交换的过程。     

基于虚拟仪器的温湿度测量系统设计与实现

温湿度测量系统是特殊要求实验室必备的测量仪器,传统的实验室温湿度测量装置是以单片机为核心,用数码管显示湿度值,根据不同的温湿度要求,通过硬件设定不同的调节终态,从而将实验空间的湿度调节到设定值.为了更好地了解特殊要求实验室的温湿度变化规律,传统的测试装置已经不能适应实验室的需要.利用虚拟仪器技术设计制作温湿度测控系统,使用LabVIEW和数据采集卡相互配合采集温湿度信号并输出控制信号,结果显示更形象直观,操作更方便,并且还可以较容易地实现功能扩展.     

脑电信号放大与预处理器电路设计

本文根据脑电信号很微弱，其幅值只有几——几十微伏（μV），并且淹没在大量的随机噪声中这一条件，设计了一种能将脑电信号放大5000-50000倍的增益＂qN电路。为了消除干扰，抑制噪声，保证测量的正确性，设计了EEG（Electro—Encephalogram）高通滤波器、EEG低通滤波器和EEG带通滤波器。将该系统应用于试验，试验结果表明该系统有较好的适用价值。     

简化的模糊PID控制方案

提出一种简化模糊PID控制方案，将三维的控制规则库简化为二维，大大减少了模糊控制规则的数目，简化了控制策略及控制器的设计和调整过程。并讨论了该控制器的调整方法，最后通过仿真验证了其优越的性能。     

Oscillation behaviour of the enlarged European power system under deregulated energy market conditions

Aimed power system simulations are carried out to analyse the bad damping behaviour of slow inter-area oscillations sporadically occurring within the European power system. To obtain application-oriented results, the simulations are carried out by a detailed power system dynamic model and compared with corresponding oscillation measurements. Using analysis methods in the time and state space, it is shown that the damping behaviour can be improved by easily applicable countermeasures.

Based on this, the foreseen enlargement of the European power system is investigated, when coupling both system ends step by step around the Mediterranean Sea to the so-called Mediterranean Ring. Also these predictive considerations lead to very interesting oscillation and damping results.     

称重式皮带给煤机在火电厂应用中存在的问题及改进

简述了HD-BSC26型皮带给煤机的给煤量控制原理,重点对该型给煤机在实际运行中出现的问题进行分析并提出了可行的改进方案,为其它电厂改进同类型给煤机控制有较好的参考价值。     

A topological obstruction to continuous global stabilization of rotational motion and the unwinding phenomenon

We show that a continuous dynamical system on a state space that has the structure of a vector bundle on a compact manifold possesses no globally asymptotically stable equilibrium. This result is directly applicable to mechanical systems having rotational degrees of freedom. In particular, the result applies to the attitude motion of a rigid body. In light of this result, we explain how attitude stabilizing controllers obtained using local coordinates lead to unwinding instead of global asymptotic stability.     

Uniform exponential stability of linear time-varying systems: revisited

Some classical results known in the adaptive control literature are often used as analysis tools for nonlinear systems by evaluating the nonlinear differential equations along trajectories. While this technique is widely used, as we remark through examples, one must take special care in the consideration of the initial conditions in order to conclude uniform convergence. One way of taking care explicitly of the initial conditions is to study parameterized linear time-varying systems. This paper re-establishes known results for linear time-varying systems via new techniques while stressing the importance of imposing that the formulated sufficient and necessary conditions must hold uniformly in the parameter. Our proofs are based on modern tools which can be interpreted as an “integral” version of Lyapunov theorems; rather than on the concept of uniform complete observability which is most common in the literature.     

变频器及PLC在焙烧多功能天车上的应用

针对天车电气控制技术落后的问题,采用变频器及PLC对炭素焙烧多功能天车的电气系统进行改进。本文介绍了本课题改进的具体内容及实施后的效果,满足了天车的各种工艺要求,提高了焙烧多功能天车综合性能。