ZBT-11微机保护器在井下变电所的应用

针对目前煤矿井下高压开关保护存在的弊端,提出一种新的微机保护器,重点介绍硬件功能,改造方法及保护整定方法等。经实际应用,煤矿供电系统可靠性得到提高,经济效益和社会效益显著,具有良好的推广应用前景。     

煤矿井下采区无人值守变电所微机保护系统的研究

在分析目前煤矿井下安全现状的基础上 ,深入研究了煤矿井下供电系统各种常见故障的特征、相关保护原理及算法 ,研制出一套针对井下采区变电所的微机综合保护、监控装置。实践证明 ,该装置经济效益和社会效益显著 ,具有良好的推广应用前景。     

煤矿井下供电过流保护的改进

由于煤矿井下供电的特殊性,过流保护经常发生误动和拒动,严重威胁煤矿自身的安全。针对煤矿井下供电过流保护的问题,分析了引起煤矿井下供电过流保护误动和拒动的原因,在传统的过流保护基础上,作出了新的改进,理论表明该方法有很好的保护性能。     

煤矿井下供电短路保护新设想

分析了煤矿井下供电保护实际应用中存在的问题,介绍了目前煤矿现场进行短路保护的措施,提出了煤矿井下供电短路保护新设想。     

浅谈煤矿井下高压供电网络区域选择性联锁保护

 摘要：本文结合图论对煤矿井下高压供电网络进行规划，通过浅谈煤矿井下高压供电网络区域选择性联锁保护的基本原理和结构，提出了网络化的煤矿井下供电系统保护配置策略，主要是用于解决煤矿井下供电系统的越级跳闸问题。     

高压隔爆开关漏电保护插件的硬件电路设计

文章针对煤矿井下高压隔爆开关漏电保护插件的硬件电路进行了设计,采用高性能DSP处理器TMS320C6747作为保护装置的中央处理单元,提高了装置的性能;采用RS-485和CAN串行通讯接口,实现了微机保护装置和上位PC机之间的远程数据通讯。该设计方案可以对井下高压电网漏电起到良好的保护作用,缩短井下供电的高压开关速断保护动作时间,有效提高井下供电系统的可靠性。     

仟伏级供电系统中的漏电保护问题

我国在煤矿井下供电网路的漏电保护方面已有很多成功的经验。近几年来,随着采煤综合机械化的发展,供电电压已提高到1100伏。在这种情况下给漏电保护工作提出     

可编程监测控制系统在带式输送机上的应用

<正>以BXWⅡ-120/115矿用隔爆兼本安型微机控制箱为核心的电控系统,是兖州煤矿机械厂专门为煤矿井下研制的可编程监测控制系统,输入输出点数可扩展,语音通讯,可自诊断并具有快开门结构,目前已广泛用于煤矿井下带式输送机电气控制、监测和综合保护。     

井下高压电网微机选择性速断短路保护方案研究

在分析我国井下高压电网短路故障的基础上,深入研究相关的保护原理及提高井下高压电网短路保护灵敏度和可靠性的方法,设计出新型的利用计算机通信与逻辑识别技术的井下高压电网微机选择性速断短路保护方案,将微机保护应用于煤矿井下高压电网,通过多机通信、逻辑判断判定线路故障段,从而做到快速的、有选择性的切断故障线路,避免煤矿井下高压电网因越级跳闸而造成大面积停电。     

自动调谐动态补偿消弧装置在矿井供电系统中的应用

介绍了煤矿井下供电系统电容电流治理的必要性、漏电电容电流计算方法等。阐述了煤矿供电电容电流的治理方法,通过设计微机控制自动调谐动态补偿消弧线圈及其微机控制器的硬件、软件,并加以应用,提高了亭南煤业公司的供电管理水平,保证了矿井的供电安全。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

2014 second batch of rare earth quota released

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矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586