电容电流对供电系统的影响及消解

结合供电系统的实际情况,分析了电容电流在小电流接地供电系统中的存在原因、电弧的产生、危害、及通过消弧线圈进行消解的技术措施。     

关于6—10kV小接地电流系统装设消弧线圈必要性的探讨

本文在简介小接地电流系统的基础上，提出了接地电容电流的图解计算方法，并以首钢七总降１０ｋＶ侧运行情况为例，给出了在首钢６￣１０ｋＶ小接地电流系统中装设消弧线圈的必要条件。     

本钢10KV供电网接地电容电流的补偿与调谐

本文介绍了在本钢10KV供电网中，自动补偿接地电容电流的重要性及可行性。     

小电流接法系统接地电容电流的测试

结合工作中的实际问题，对小电流法系统单流接地系统单相不接地容电流进行测试和探讨，提出了构思新颖，实用性强的测试方法。     

消弧接地补偿系统改造评析

蕾钢发电厂10kV母线为降低分布电容电流对系统发生接地故障时造成危害，而采用了消弧线圈补偿分布电容电流。因旧式消弧线圈技术落后，满足不了安全运行需要，于2003年引进了XHJZ智能型消弧限压接地补偿装置，取代了原有消弧线圈．对消弧接地补偿系统改造前后进行了分析与评价。     

动力变电站10kV系统接地现状分析

文章介绍了某钢铁企业动力变电站10kV系统接地现状以及变电站采用的中性点消弧线圈接地装置工作原理.通过对现有系统接地电容电流计算,分析了动力变电站接地系统存在的不足,提出了改进建议,同时对全电缆配电网宜采用的接地方式提出了建议.     

接地电容电流的实测及补偿

介绍了如何实测接地电容电流及进行补偿．     

改进希尔伯特黄变换理论在配电网故障选线中的应用与研究

将一种新的非线性、非平稳信号处理方法-改进HHT(Hilbert-Huang Transform)方法应用于配电网故障选线中.改进HHT方法可以从非平稳的故障信号中准确地提取丰富的系统故障暂态信息.通过对故障后各线路零序电流特征分析,进而利用HHT提取零序电流高频分量幅值、频率和相位等信息,比较幅值和相位实现正确选线.理论分析和大量的ATP仿真结果表明:基于改进HHT的选线方法可以准确、可靠地实现中性点经消弧线圈接地配电网单相接地故障选线.     

模糊控制在配电网单相接地故障选线中的研究

在小电流接地系统中,现有单相接地故障选线装置适应性较差、正确率不高,为此,提出了基于模糊综合决策的多重复和判据方案由MATLAB仿真实验证明,该方案能有效弥补单…判据的不足,不受小电流接地系统结构及运行方式变化的影响,完全实现单相接地故障的正确选线。     

汽车用户加工配送中心设备选型分析

随着汽车制造厂越来越多地把钢材加工配送的业务外包,针对汽车主机厂的加工配送中心需求增长迅速。通过对汽车用钢特点的分析,结合实际经验,提出针对汽车主机厂服务的钢材加工配送中心设备的选型原则及不同设备的关键参数;对如何分析汽车用户的需求,合理配置加工配送中心的设备类型及确定各设备的关键参数,以满足用户的需求提出建议。     

增加电网无功补偿的效能分析

通过对感性负载电网的有功、无功分析,使用无功补偿对电网的作用理论上对提高供电效率和电网无功损耗的节能进行了全面的理论分析得出节能增效的结果.     

Water Distribution Network Analysis Using Excel

The analysis of water distribution networks has been and will continue to be a core component of civil engineering water resources curricula. Since its introduction in 1936, the Hardy Cross method has been used in virtually every water resources engineering text to introduce students to network analysis. The technique gained widespread popularity primarily because it is amenable to manual calculation techniques. However, the same subtle elegance that facilitates manual calculations often obscures the primary engineering and physical principles of water distribution systems relative to the nuances of algorithm implementation. Herein, the authors illustrate the application of commonly available spreadsheet software (MicroSoft Excel) to more concisely and effectively solve typical undergraduate network distribution problems using linear theory. Application development is much more efficient and straightforward than the corresponding Hardy Cross implementation enabling students to concentrate upon the engineering system and relevant design issues. The technique presented utilizes commonly available technology and is presented as a supplement to alternatives discussed in recent literature.     

Quantitative Methods for Design-Build Team Selection

The use of design/build (DB) contracting by transportation agencies has been steadily increasing as a project delivery system for large complex highway projects. However, moving to DB from traditional design-bid-build procurement can be a challenge. One significant barrier is gaining acceptance of a best-value selection process in which technical aspects of a proposal are considered separately and then combined with price to determine the winning proposal. These technical aspects mostly consist of qualitative criteria, thus making room for human errors or biases. Any perceived presence of bias or influence in the selection process can lead to public mistrust and protests by bidders. It is important that a rigorous quantitative mathematical analysis of the evaluation process be conducted to determine whether bias exists and to eliminate it. The paper discusses two potential sources of bias—evaluators and weighting model—in the DB selection process and presents mathematical models to detect and remove biases should they exist. A score normalization model deals with biases from the evaluators; then a graphical weight-space volume model and a Monte Carlo statistical sampling model are developed to remove biases from the weighting model. The models are then tested and demonstrated using results from the DB bridge replacement project for the collapsed Mississippi River bridge of Interstate 35W in Minneapolis.     

露天矿采场测量方法的选择与应用

露天矿采场环境特殊且工作具有流动性和频繁性,对此,后方交会和附合导线相结合是一种比较适合露采工作需要同时又能提高工作效率的测量方法。     

企业配电网电压跌落原因分析及控制策略

文章以一起电网短路故障引起电压跌落事故为例,分别从供电运行方式、继电保护整定、中低压电网抗晃电能力等方面展开论述,分析电压跌落引起用电设备跳车的原因,并提出相应的控制措施以减少事故带来的经济损失。     

整流柜均流系数测算方法的改进

传统的整流柜均流系数测算需要工作人员在正常运行或电流升高的整流柜上测量快熔两端的毫伏压降,这对测试人员和整流柜来说都存在较高的危险。使用红外线测温仪可以随时检查每条桥臂上整流元件和快熔的运行情况,套用计算均流系数的公式可以计算桥臂的温度系数,跟踪桥臂的均流变化情况,比传统的方法更安全、简便。     

热轧板带横向厚度分布神经网络预测分析

将BP神经网络相结合引入到热轧板带横向厚度分布的预测与控制中,并依据板带轧制的实际数据对网络进行训练,通过比较二辊可送轧机板带横向厚度分布的预测值与实测数据,验证该热轧板带横向厚度分布的神经网络预测模型的准确性。验证表明,该模型的应用不仅能够提高板带轧制质量,而且能够降低设备成本。