电极电流交互作用对高硅合金生产过程影响的分析

高硅合金生产过程中,大型矿热炉的电极电流交互作用明显,引起了三相电极电流变化的不可预测性,同时由于大型矿热炉电抗值较高,引起了电极移动的不敏感性,频繁移动电极对电炉的三相电极功率平衡控制带来了一定困难。文章根据矿热炉电路原理对减弱电极电流交互作用和平衡三相电极功率提出了保持三相功率平衡的控制策略和措施。     

中小型三相交流硅锰炉电气特性不平衡分析

中小型三相交流矿热炉存在严重的电气参数不平衡问题,导致冶炼过程炉况不稳、功率因数低、电耗高,难以实现冶炼过程三相熔池功率和温度场的平衡控制.以容量为12.5 MVA的三相交流硅锰炉为对象,在对其关键电气参数进行检测与计算的基础上,分析了三相短网不平衡、现有人工操作机制以及炉内变化所致不平衡对三相交流矿热炉电气特性的影响...     

电弧畸变和电抗对高硅锰硅合金生产影响的分析

在高硅锰硅合金生产过程中,电弧热为硅的还原反应提供了大部分的热能,当矿热炉内反应区条件发生改变时,电弧发生畸变,引起谐波讯号量的增加,不稳定的电弧又导致大型矿热炉电抗的增加和不平衡,引发了大型矿热炉中常见的"死相"、"活相"及电极不敏感等问题。并对生产过程中引起电抗变化和电弧畸变的操作进行了分析。     

余热发电应用前矿热炉的改造

为提高矿热炉配套余热发电系统的发电功率,在矿热炉配套余热发电前需对生产线进行改造。对矿热炉炉体和烟风系统存在的问题进行了分析。结果表明:选择合适的改造方案、提高矿热炉余热锅炉进口烟风温度、使余热锅炉产汽不低于设计参数,可保证余热发电系统的发电量达到设计指标。     

矿热炉的节电途径

通过寻找最大有效功率来确定矿热炉超负荷的界限,使矿热炉运行在最大有效功率的近前区.用经验算法确定矿热炉尺寸,并同现有矿热炉对比查找问题,使配、用电协调一致,找到最佳用电.利用电力特性曲线,确定最大有效功率的出现点和最佳操作电阻,确认发挥电力最大潜力的用电位置,达到节电的目的.     

矿热炉电极作功不平衡的原因分析与实践

根据一座6．3MVA矿热炉短网布线中电抗及电阻偏大，使短网铜排压降差异，造成三相电极作功不平衡，并提出改进措施，对改进前后分析比较，推导计算得出结论，减少电炉短网配置造成的电能损失，必须克制二次导体阻抗的差异而引起的功率不平衡，给冶炼过程造成的不良的影响。特别对降低单位电耗有着重要的意义。     

矿热炉三相电极电压采集器的设计应用

分析了矿热炉二次电压自电炉变压器二次出线端(低压侧)接入,由于矿热炉短网各支路感抗的不相等,导致的二次电压与实际运行电压误差较大,对矿热炉冶炼炉况的正确判断及稳定运行产生一定影响的原因,根据现场调研及分析结果,设计了矿热电炉三相电极电压采集器,可为矿热炉冶炼工艺需求及功率检测提供定量准确的运行数据。     

大型矿热炉新型铜板炉盖的开发与应用

目前国内矿热炉水冷炉盖大多采用钢结构,正常使用寿命一般在2年以内,未能适应矿热炉大型化、大功率化、自动化的发展趋势。华兴股份近年来开发一种大型矿热炉新型铜板炉盖,采用压延铜板钻孔焊接工艺,具有良好的导热性、结构强度高等特点,在国内外几个大型矿热炉得到应用,使用寿命比钢结构水冷炉盖显著提高。     

矿热炉电极作功不平衡的原因分析与实践

本文根据一座6300kV·A矿热炉短网布线中电抗及电阻偏大,造成三相电极作功不平衡这一问题,提出改进措施,并对改进前后分析比较,说明改造是成功的。对新建成改造矿热炉具有推广应用价值。     

矿热炉传统设计理论研究(2)——威斯特里公式

为满足大型矿热炉设计需要,对传统设计公式重新进行整理分析。文章首先对威斯特里公式及其应用进行简单介绍,随后将斯特隆斯基公式与之对比,并提出了矿热炉设计理论研究的两种思路,最后对以安德烈公式为基础的一系列设计理论进行了整理分析,并指出在大型矿热炉中应用传统设计理论需要进一步解决的问题。     

Characteristics of electric arc furnaces powered by a low-frequency alternating current

The changes in the parameters of a DSP-100 electric arc furnace that are induced by a decrease in the current frequency are considered. It is shown that the related decrease in the current lead resistances causes an increase in the arc power and voltage, a decrease in the reactive power, and an increase in the electrical efficiency and the power coefficient. The heat indices are expected to be significantly improved.     

L-C恒流高压直流电源在烧结机静电除尘器上的应用

对比了可控硅高压直流电源与L-C恒流高压直流电源在烧结机静电除尘器上的使用情况,阐述了两种电源的控制方式及结构特点.实践表明,L-C恒流高压直流电源的适应性、稳定性和除尘效率等均优于可控硅电源.     

恒流源在焦炉电捕焦油器中的运用

介绍了L-C恒流源在焦炉电捕焦油器中的运用，并与恒压源进行了比较，说明了恒流源的优点，同时分析了电捕焦油器运行易发生的电气故障及形成原因，提出了相应的措施。     

A new shunt DC active filter of power supply in a steady high magnetic field facility

A DC active power filter is an indispensable part in a high power and high stability power supply system, especially in the power supply system of the Steady High Magnetic Field Facility, which requires that the current ripple should be limited to 50 part     

并联节电器在配电系统中的应用研究

通过对电网瞬流、谐波形成的原因,瞬流对电气设备造成的危害,对计量装置准确计量产生的影响进行分析,提出使用并联节电器解决瞬流问题;并进一步对3^#变压器的主母线进行测试分析,制定出低压配电系统的简化方案。经对3^#变压器安装并联节电器前后的用电量进行统计、分析,说明并联节电器具有较高的节电效果,且运行稳定,适宜在工矿企业应用。     

铸钢用50 t/32 MVA交流电弧炉炼钢过程电气运行特性

使用电气监测仪表对中信重工机械股份有限公司50t/32 MVA交流电弧炉炼钢过程中的电气参数进行了实测,得到52 310个有效数据。结果表明,有载条件下电抗器上端的功率因数均为0.800以上,供电回路中的电压、电流以及功率因数均处于三相平衡状态。以二次侧工作电流为自变量,建立非线性电抗模型,绘制电气运行特性曲线,确定现用各挡电压下的工作电流许用范围。研究表明,若将电抗器挡位由原来的3挡改设为4挡运行,则炉用变压器容量利用率将提高7.30%,功率因数将由原来的0.812提高为0.841。     

Interactions of variables in the fluidised-bed electrowinning of copper

The effects of certain variables on the current efficiency and power consumption of a small fluidised-bed electrowinning cell treating dilute copper sulphate solutions have been studied. A factorial experimental design in two levels has been used to investigate the effects of cell current, sulphuric acid concentration, temperature and the presence of iron in the electrolyte, and the results have been analysed by the Yates technique.It is shown that an increase in temperature and the presence of iron in solution both decrease the current efficiency, while an increase in the cell current increases the current efficiency, for conditions where the cathode is not polarized with respect to copper ions. Significant interaction effects on the current efficiency are shown to exist for the case of cell current and iron concentration and for cell current and temperature. These main effects and interactions can be accounted for by a model in which three simultaneous reduction reactions occur at the cathode involving cupric ions, ferric ions and oxygen, with the latter two occurring at their diffusion limited rates.Significant main effects on the power consumption of the cell are shown to exist for cell current, iron concentration and acid concentration. Increasing either of the former two variables increases the power consumption whereas an increase in the latter causes a marked decrease in power consumption, and significant interactions occur between cell current and iron concentration and cell current and acid concentration.An increase in temperature is shown to lead to an increase in the amount of metal deposited on the feeder electrode.The paper concludes with a discussion of the application of fluidised-bed cathodes to the recovery of copper by electrowinning from various types of solutions.     

Government Policy and Future Projection for Nuclear Power in China

The Chinese government has set ambitious goals for nuclear power. By 2020, China must reach a 40-GW nuclear power generation capacity, have 18?GW of additional nuclear power capacity under construction, and ensure that approximately 4% of electricity generation (i.e., 260–280?billion?kWh) comes from nuclear power. This paper provides an overview of nuclear power development in China and analyzes the roles of nuclear power manufacturers and investors. This paper further discusses current government policies, potential changes to current policy, the future of nuclear power, and the barriers to nuclear power development in China. The paper then summarizes the experiences of other countries with successful stories in developing nuclear power. Finally, recommendations for overcoming the various obstacles to nuclear power development in China are proposed, such as reforming the structure of China’s nuclear power industry, establishing an effective legal system for nuclear power safety, and improving China’s technology development.     

Numerical Study on the Effect of Low-Frequency Power Supply on Desulfurization in the Electroslag Remelting Process

In the electroslag remelting (ESR) process, low-frequency power supply can significantly reduce power consumption and achieve three-phase balance of power supply. Therefore, a transient coupling model of fluid flow, heat transfer, and component transport in the ESR process, which is coupled to the electromagnetic field calculated using Maxwell 3D software, is established to study the influence of low-frequency power supply on desulfurization. When a 50 Hz power supply is used, a skin effect is observed in the metal, and the direction of the Lorentz force at the slag/metal interface changes. However, this effect becomes less pronounced with decreasing current frequency. Sulfur is mainly transferred at the electrode tip, and the desulfurization rate is approximately 50%. Electrochemical reactions mainly occur at the electrode tip/slag interface and the metal pool/slag interface. The removal rate of sulfur using direct current (DC) power supply is less than that using an alternating current power supply. The DC reverse polarity power supply leads to higher desulfurization rate than DC straight polarity, which is 74% and 31%, respectively. The sulfur removal rate increases from 81.37% to 84.59% as the frequency decreases from 50 to 2 Hz because of the longer electrochemical reaction time at this lower frequency.     

35kV系统限流电抗器在变电站中的研究与应用

电抗器是用来限制电路中的短路电流和提高系统的残压,利用其电感特性。降低短路电流对电网的冲击,保护电网的稳定性。同时电抗器会在线路中损耗一部分电压和电能。老式的电抗器,由于压降较大,为了保证用户端的电压等级达标,就必须增加电源端的电压等级。当电源端的电压等级提高就加速了输电设备的绝缘老化,增加了故障发生率,所以需探讨限流电抗器在变电站中的安全应用。