台达VE系列变频器在桥式起重机中的应用

本文介绍了桥式起重机的工作原理和应用环境,详细阐述了台达VFD—VE系列变频器应用于行车电动机的变频驱动原理与功能模式。为VFD—VE变频器在行车行业中的应用提供了参考。     

台达机电产品在塑料薄膜生产线上的应用

本文主要介绍了台达机电产品（触摸屏、PLC、变频器、温控器等）在塑料薄膜生产线上的整合应用。该控制系统操作界面友好简单,结合台达HMI、PLC和变频器等工控产品,实现了设备的技术升级与高效节能,体现出台达自动化产品较高的性价比。运行实践证明,台达产品稳定可靠,控制效率高,值得业界同行借鉴和推广。     

台达机电产品在木工机械上的应用

本文就以木工机械中的砂光机为例,介绍台达机电产品在其设备上的综合应用。该控制系统基于台达HMI、PLC和变频器等自动化产品,实现了设备的技术升级与高效节能,体现出台达自动化产品较高的性价比。该系统的实际运行效果,表明了台达产品稳定可靠,操作直观简单,控制效率高,值得业界同行借鉴和推广。     

Exponential stabilization of discrete-time switched linear systems

This article studies the exponential stabilization problem for discrete-time switched linear systems based on a control-Lyapunov function approach. It is proved that a switched linear system is exponentially stabilizable if and only if there exists a piecewise quadratic control-Lyapunov function. Such a converse control-Lyapunov function theorem justifies many of the earlier synthesis methods that have adopted piecewise quadratic Lyapunov functions for convenience or heuristic reasons. In addition, it is also proved that if a switched linear system is exponentially stabilizable, then it must be stabilizable by a stationary suboptimal policy of a related switched linear-quadratic regulator (LQR) problem. Motivated by some recent results of the switched LQR problem, an efficient algorithm is proposed, which is guaranteed to yield a control-Lyapunov function and a stabilizing policy whenever the system is exponentially stabilizable.     

High-gain observers in the presence of measurement noise: A switched-gain approach

This paper considers output feedback control using high-gain observers in the presence of measurement noise for a class of nonlinear systems. We study stability in the presence of measurement noise and illustrate the tradeoff when selecting the observer gain between state reconstruction speed and robustness to model uncertainty on the one hand versus amplification of noise on the other. Based on this tradeoff we propose a high-gain observer that switches between two gain values. This scheme is able to quickly recover the system states during large estimation error and reduce the effect of measurement noise in a neighborhood of the origin of the estimation error. We argue boundedness and ultimate boundedness of the closed-loop system under switched-gain output feedback.     

Stabilizing switching design for switched linear systems: A state-feedback path-wise switching approach

This paper addresses the problem of switching stabilization for discrete-time switched linear systems. Based on the abstraction-aggregation methodology, we propose a state-feedback path-wise switching law, which is a state-feedback concatenation from a finite set of switching paths each defined over a finite time interval. We prove that the set of state-feedback path-wise switching laws is universal in the sense that any stabilizable switched linear system admits a stabilizing switching law in this set. We further develop a computational procedure to calculate a stabilizing switching law in the set.     

高速ADC频域特性测试系统的设计

针对传统专用高速模数转换器频域特性测试系统构建难度大、成本高的问题,利用基于加窗和插值FFr算法的测试方法,提出一种低成本高速ADC频域特性测试系统,给出ADC采样时钟驱动电路、ADC输入信号驱动电路、FIFO缓存电路及USB接口电路的关键设计技术。     

跨域BGP／MPLSVPN在高性能路由器中的实现

提出在高性能路由器中跨域边界网关协议（BGP）／多协议标签交换（MPLS）虚拟专用网（VPN）的高效实现方法。结合协议规范,将转发与控制分离,主控负责对标记的分发与管理,转发引擎实现对MPLS分组的封装与转发。通过在控制层面对标记信息进行预处理,避免VPN业务分组在转发过程中的递归查找问题,使硬件转发数据包仅需一次查表,实现数据包的线速转发。     

Observability of switching structured linear systems with unknown input. A graph-theoretic approach

This paper deals with the observability of the discrete mode, the internal state and the input of switching structured linear systems with unknown input. The proposed method, based on a graph-theoretic approach, assumes only the knowledge of the system’s structure. We express, in graphical terms, necessary and sufficient conditions for the generic observability of the discrete mode, the continuous internal state and the input of a switching structured linear system. These conditions can be implemented by classical graph theory algorithms based on finding particular paths and cycles in a digraph.