Improvement of the electrohydraulic power controller of an arc furnace in foundry

Experimental data are used to develop a model for the structure of an adaptive electrohydraulic power controller for an arc furnace, and the introduction of a negative electrode velocity feedback into the electrohydraulic drive of electrode motion is shown to be useful. Model investigations of the operation of the proposed power controller under various conditions are performed, and recommendations are made to choose the parameters in designing power controllers.     

电弧炉炼钢的计算机控制

综述了电弧炉炼钢计算机控制的新进展，包括计算机控制系统的组成与功能，常用过程数模及应用，数据库管理技术以及管理电弧炉控制系统。     

液压传动交流电弧炉微机控制系统

介绍了３０ｔ液压电弧炉微机控制管理系统硬件及软件功能。     

Electrical optimization of superpowerful arc furnaces

Requirements on the systems controlling the electrical conditions of superpowerful arc furnaces in steel smelting are outlined. The basic principles for electrical optimization at different phases of smelting are considered. An improved mathematical model is proposed for analysis of the arc furnace’s electrical characteristics and the dynamics of the automatic control system governing electrode motion. A diagnostic system capable of identifying the phase of smelting on the basis of the harmonics of the arc currents shortens the furnace’s working cycle and reduces the power consumption.     

SIMADYND在交-交变频主传动中的应用

大功率轧钢机主传动要求电气传动系统具有很高动态响应和相当高的过载能力。这一领域长期以来一直被直流传动所垄断。随着电力电子技术、微电子技术以及现代控制理论的迅速发展,在大功率轧钢机主传动领域已出现交流调速传动取代直流传动的趋势。本文主要针对西门子SIMADYN-D矢量控制系统在大功率轧钢机主传动中的应用进行简要介绍。     

交流伺服驱动系统在水平连铸上的应用

本文介绍了交流伺服驱动系统的组成、主要特性、工作原理以及在水平连铸上的应用。并对液压伺服、直流伺服和交流伺服系统进行了比较．交流伺服系统表现出其明显的发展优势。     

珠钢计算机系统及其特点

珠江钢厂是国内第一个采用电炉+精炼+薄板坯连铸连轧短流程工艺生产热轧薄板的现代化钢厂.它配备了由基础自动化、过程控制计算机和生产控制计算机所组成的三级自动化控制系统,具有九十年代国际先进水平,本文介绍珠钢计算机控制系统的概况及主要特点.     

基于TDC控制和全变频调速的热连轧卷取机电控系统

随着现代热连轧生产工艺的不断提高,对热轧卷取机的控制系统也提出了更高要求,日照钢铁有限公司1 580mm热连轧机生产线是2006年底投产的一条依托国内力量自主完成的现代化热轧生产线,其卷取控制系统采用了先进的TDC控制器和交直交变频驱动方式,本文主要介绍这套电控系统的硬件配置和功能特点.     

连铸结晶器混合驱动系统的非正弦振动波形

 针对频率、振幅和波形均可在线调整的连铸结晶器电动式混合驱动系统,提出与其运行模式相匹配的非正弦振动波形。首先阐明新型驱动系统非正弦波形的发生机理;然后按照激波机构的运行特点,考虑系统运行过程中的平稳性和运动约束条件,构建了激波机构的速度函数,进而根据驱动系统运动学推导出以频率、振幅和偏斜率为基本参数的结晶器非正弦振动波形;最后给出非正弦波形的关键工艺参数计算公式,讨论了[vc-f、h]同步控制模型中控制参数与振动工艺参数的关联规律,并以某中碳钢板坯连铸生产为例,利用关联规律,得到了完全符合振动工艺原则的非正弦控制模型,从而验证了该非正弦波形的有效性和实用性。     

济钢90m~2烧结机半悬挂多柔传动的动力学分析

通过对济钢９０ｍ２烧结机驱动装置的动力学分析,提出了驱动系统的角位移的和扭振力矩的运动表达式,以及如何解决生产中出现的问题和应注意的问题,为在生产中减少或避免设备事故的发生提供了帮助。     

现代铝带热轧机传动电控系统

本文主要以ABB公司的DCS502B全数字直流传动模块、ACS600交流多传动控制模块和西门子公司的S7-300程控器等完成的1300mm铝板带热轧机电控系统为例,介绍了现代铝带热轧机传动电控系统的硬件、软件设计,并着重介绍了辊道电机的控制思想。     

SDMCNC-10型卧轴矩台圆弧剪刃数控成型磨床的技术改进

简要介绍了SDMCNC-10型卧轴矩台圆弧剪刃数控成型磨床的几项技术改进,包括机床导轨、传动滚珠丝杆、砂轮进刀A C变频无级调速系统、西门子802D控制系统应用、计算机控制人机对话窗口设定以及润滑等方面的改进.改进、使用后的机床在同型磨床装备和实用技术上达到国内先进水平.     

珠江钢厂生产控制计算机系统

珠江钢厂是国内第１个采用电炉＋精炼＋薄板坯连铸连轧短流程工艺生产热轧薄板的现代化钢厂,该钢厂采用了先进的计算机生产控制系统,实现了对全厂生产计划的编排和在线产品质量的判定。     

钢轨高精度自动定尺的研究

针对我国钢轨生产企业钢轨加工过程中挡板定尺存在的问题,鞍钢大型厂研制开发了新型定尺系统.该系统利用光栅和伺服传动作为控制手段,实现了定尺自动化、精确、灵活的统一,是我国第一套高精度定尺系统,达到了国内先进水平.     

大型转炉的倾动控制

介绍上海宝钢集团公司三期扩建工程二炼钢厂新建2座250t转炉倾动系统的供电、传动、备用蓄电池容量计算及主要控制功能。该工程已于1998年4月热负荷试车成功，目前运行效果良好。     

钢铁工业自动化的进展与展望

叙述了钢铁工业自动化在ＤＣＳ、人工智能技术、ＣＩＭＳ、现代控制理论和交流传动技术等方面的进展，以及钢铁工业自动化的发展趋势。     

现代交流调速系统的性能指标

介绍了现代交流调速系统的主要性能指标及其定义方式，给出了国际上几个主要电气公司（ＧＥＳＩＥＭＥＮＳ，ＡＢＢ，ＴＯＳＨＩＢＡ）在轧钢机主辅传动系统方面的性能指标。     

Intensity-modulated arc therapy with dynamic multileaf collimation: an alternative to tomotherapy

The desire to improve local tumour control and cure more cancer patients, coupled with advances in computer technology and linear accelerator design, has spurred the developments of three-dimensional conformal radiotherapy techniques. Optimized treatment plans, aiming to deliver high dose to the target while minimizing dose to the surrounding tissues, can be delivered with multiple fields each with spatially modulated beam intensities or with multiple-slice treatments. This paper introduces a new method, intensity-modulated arc therapy (IMAT), for delivering optimized treatment plans to improve the therapeutic ratio. It utilizes continuous gantry motion as in conventional arc therapy. Unlike conventional arc therapy, the field shape, which is conformed with the multileaf collimator, changes during gantry rotation. Arbitrary two-dimensional beam intensify distributions at different beam angles are delivered with multiple superimposing arcs. A system capable of delivering the IMAT has been implemented. An example is given that illustrates the feasibility of this new method. Advantages of this new technique over tomotherapy and other slice-based delivery schemes are also discussed.     

大功率轧机主电机电气传动方案的分析与比较

交流传动调速系统性能已经大大超过直流传动调速系统,交流传动技术在新建的轧机主传动中已经成为主导技术,交流传动系统又分为交 交传动和交 直 交传动两种传动方式,为此本文对交 交变频和交 直 交变频进行了深入的分析和比较,为大功率轧机主电机传动装置的设计选型提供参考。     

Control of vacuum arc furnaces

Control of a vacuum arc furnace by means of a programmed step in the melting process is described. A model of voltage control in a vacuum arc furnace was considered in [1, 2]. However, the control algorithm is associated with considerable static error. The error may be reduced using a programmed step, corresponding to previously calculated motion of the consumable electrode so as to maintain constant melting rate and a specified range of the electrode gap. By this means, blind control of melting in the vacuum arc furnace, without any feedback, is possible for ideal electrodes. In the case of nonideal (real) electrodes, however, such blind control cannot maintain the required melting parameters. Therefore, in that case, voltage feedback must be employed. Matlab software is used for simulation of the process in the case of ideal and nonideal consumable electrodes.