A comparison of a novel robust decentralised control strategy and MPC for industrial high purity,high recovery,multicomponent distillation

In this work we have developed a novel, robust practical control structure to regulate an industrial methanol distillation column. This proposed control scheme is based on a override control framework and can manage a non-key trace ethanol product impurity specification while maintaining high product recovery. For comparison purposes, a MPC with a discrete process model (based on step tests) was also developed and tested. The results from process disturbance testing shows that, both the MPC and the proposed controller were capable of maintaining both the trace level ethanol specification in the distillate (X_D) and high product recovery (β). Closer analysis revealed that the MPC controller has a tighter X_D control, while the proposed controller was tighter in β control. The tight X_D control allowed the MPC to operate at a higher X_D set point (closer to the 10 ppm AA grade methanol standard), allowing for savings in energy usage. Despite the energy savings of the MPC, the proposed control scheme has lower installation and running costs. An economic analysis revealed a multitude of other external economic and plant design factors, that should be considered when making a decision between the two controllers. In general, we found relatively high energy costs favour MPC.     

CDMA系统定位接口协议分析与实现

现有的移动通信网络如果要支持定位业务,就必须对网络进行改造,本文从网络实体和信令流程两方面介绍了网络升级的内容,并给出了定位接口协议的实现方案。文章对深入了解定位技术具有一定的参考价值。     

DISOPE distributed model predictive control of cascade systems with network communication

A novel distributed model predictive control scheme based on dynamic integrated system optimization and parameter estimation (DISOPE) was proposed for nonlinear cascade systems under net work environment.Under the distributed control structure ,online optimization of the cascade system was composed of several cascaded agents that can cooperate and exchange information via network communication.By iterating on modified distributed lin ear optimal control problems on the basis of est imating parameters at every iteration the correct op timal control action of the nonlinear model predicti ve control problem of the cascade system could b e obtained,assuming that the algorithm was convergen t.This approach avoids solving the complex nonlinear optimi zation problem and significantly reduces the computation al burden.The simulation results of the fossil f uel power unit are illustrated to verify the eff ectiveness and practicability of the proposed algorithm.     

Input-to-state stable finite horizon MPC for neutrally stable linear discrete-time systems with input constraints

MPC or model predictive control is representative of control methods which are able to handle inequality constraints. Closed-loop stability can therefore be ensured only locally in the presence of constraints of this type. However, if the system is neutrally stable, and if the constraints are imposed only on the input, global asymptotic stability can be obtained; until recently, use of infinite horizons was thought to be inevitable in this case. A globally stabilizing finite-horizon MPC has lately been suggested for neutrally stable continuous-time systems using a non-quadratic terminal cost which consists of cubic as well as quadratic functions of the state. The idea originates from the so-called small gain control, where the global stability is proven using a non-quadratic Lyapunov function. The newly developed finite-horizon MPC employs the same form of Lyapunov function as the terminal cost, thereby leading to global asymptotic stability. A discrete-time version of this finite-horizon MPC is presented here. Furthermore, it is proved that the closed-loop system resulting from the proposed MPC is ISS (Input-to-State Stable), provided that the external disturbance is sufficiently small. The proposed MPC algorithm is also coded using an SQP (Sequential Quadratic Programming) algorithm, and simulation results are given to show the effectiveness of the method.     

MPC860软件看门狗的原理及应用

本文简要介绍了软件看门狗的基本原理，重点介绍了MPC860软件看门狗的功能和应用，着重阐述了MPC860软件看门狗使能和刷新的具体时机及操作。     

嵌入式网络视频服务器的设计

网络视频服务器集视频采集、实时压缩、网络传输等功能于一体,应用领域广泛。介绍了一种嵌入式网络视频服务器的实现方案,采用MPC860T作为主CPU,实现对音视频编解码芯片AT2042及视频采集芯片TVP5150的控制,并实现了数字视频信号的网络传输功能。给出了网络视频服务器的软、硬件实现方法。     

基于VxWorks的嵌入式网络视频服务器设计

网络视频服务器是一种嵌入式数字远程监控系统，它集视频采集、实时压缩和网络传输等功能为一体，本文提出了基于VxWorks平台的网络视频服务器的实现方案，在介绍实时操作系统Vxworks和MPC860T的基础上，结合音视频编解码芯片AT2042，给出了网络视频服务器的软、硬件实现方法。     

基于MPC860T的嵌入式通信服务器的设计与实现

串口通信服务器是将各种串行设备接入互联网的关键设备,论文提出了一个基于VxWorks和MPC860T平台的嵌入式串口通信服务器的解决方案,给出了该服务器的硬件设计和相应的BSP及服务器配置软件的详细实现。基于该体系结构的嵌入式串口通信服务器可以提供各种串行设备,特别是高速串行设备的接入以实现基于互联网的遥测遥控。     

Linux环境下基于I2C总线的EEPROM驱动程序

I2C总线是由Philips公司开发的用于器件之间连接的2线式双向同步串行总线.Linux内核中针对I2C总线的特性,其设备驱动使用了一种特殊的体系结构.介绍了MPC8250处理器上I2C总线控制器的工作原理,并分析了Linux中I2C总线驱动的体系结构,以MPC8250上的I2C总线为例,给出了I2C总线EEPROM驱动程序的设计方法.     

特高压直流分层接入下交直流系统中长期电压稳定协调控制

与传统特高压直流单层接入方式相比,分层接入方式从电网结构上改善了交流系统对多馈入直流系统的接纳能力和电压支撑能力,在潮流分布与控制上更加灵活、合理。为了充分利用分层接入直流系统快速功率调节能力,避免或减少中长期电压失稳过程中切负荷造成的经济损失,文中提出一种特高压直流分层接入下的交直流系统中长期电压稳定协调控制方法。首先,基于直流分层接入系统准稳态模型,推导了不同直流控制方式下换流母线电压对分层接入直流逆变器传输功率的灵敏度解析表达式,并建立交直流系统电压轨迹预测模型。综合考虑直流电流和高、低端逆变器熄弧角的调制,基于预测轨迹构建协调电压控制的滚动优化模型,对直流分层注入功率和交流系统各电压控制手段进行协调控制。对山东电网规划系统的仿真分析表明,所提方法能够有效协调直流传输功率在交流电网中的分配,提高了系统电压稳定性并减少了切负荷损失。