汽轮机轴承振动保护优化改造

针对近期某电厂汽轮发电机组因轴承振动大导致的机组恶性事故,汽轮发电机组的轴承振动大保护已不能单靠运行人员根据运行经验来决定是否采取措施,本文则介绍了汽轮机振动大保护优化的方法,分别实现机组并网前后实时准确的保护投入,避免人为因素导致机组事故的发生,保障机组的安全稳定运行。     

NS2100大型汽轮发电机组监测和分析诊断系统的应用分析

对国产NS2100汽轮发电机组监测和分析诊断系统在200MW机组的应用进行分析,较单一的汽轮机监测系统其功能既能实时监测,又可对转机性能、运行状态进行分析判断,从而提高大型机组运行的安全性与可靠性。     

浅谈电厂300MW机组协调控制系统的优化

电力资源的优化配置是现代化发电企业的基本需求,也是符合国家相关能源管理的需求,电厂机组热控自动化水平直接影响着电力企业的安全运行生产,故发电机组自动控制系统得到了广泛的应用。机组协调控制系统是稳定发电厂能源控制、发电量控制等其他方面控制的基础,保证机组运行的稳定性的前提下能够有效的提高机组的发电效率。本文主要对协调控制的目的以及控制方式进行分析,并提出了相应的优化策略。     

达拉特发电厂#2机组#7、#8瓦甩油现象的原因分析及对策

本文分析了汽轮发电机组甩油的原因,提出了防范措施,对同类机组的运行具有参考意义。     

海上型风力发电机组冗余安全链设计

海上型风力发电机组具有维护不便的突出特点,对机组的可靠性及安全性提出了更高的要求。安全链是风力发电机组最后一道保护,对机组的安全性起到了至关重要的作用。为提高机组的安全性,提出一种适用于海上风力发电机组的冗余安全系统,并通过倍福TwinSAFE安全逻辑模块实现了风电机组的冗余安全链设计。     

常规岛长期停运期间的保养

某核电项目,安装两台百万汽轮发电机组,汽轮发电机机组安装结束至正式运行间隔时间长,同时由于项目所处位置在沿海地区,空气湿度达,空气中盐分含量也比较高,如果汽轮发电机组保养不当,必然会加重设备腐蚀程度。以设备维修保养手册为基础,参考同类型机组,制定了详细的保养程序,减缓腐蚀,确保了机组在长期停运期间的良好状态。     

高加解列控制原理分析与改进

本文依据豫联电厂300MW亚临界汽轮发电机组高加系统,分析高加系统解列的控制流程和减少系统误动作的改进措施,通过改进高加系统解列操作流程和联锁保护逻辑,提高了机组运行的安全性,有效防止了运行人员的误操作,方便高加解列阀的检修。     

电厂热控保护误动及拒动原因浅析及对策

对热控保护误动及拒动原因进行分析和总结,提出了防止热控保护误动及拒动应采取的措施和技术对策,以提高发电机组保护的整体可靠性,保证机组安全稳定运行.     

水利发电厂发电机检修探讨

为了适应水电站的不同自然条件,水轮发电机组的转速和容量有着很大的变化范围。水轮发电机组并网和起动速度快,除了发电工作之外,还作为事故备用和调峰机组。水轮发电机作为机电能量转换的特殊装置,其运行能力决定了水利发电厂的供电安全性。本文就此对水力发电厂发电机的检修问题进行探讨,从而提高检测、排除发电机故障的能力。     

关于双馈异步发电机组因高频轴电压导致轴承损坏分析

双馈异步风电机组是目前最成熟的机型,各大风机厂商生产机组大都已双馈机型为主,因为双馈机型较永磁直驱风力发电机组有结构和技术上的优势,永磁直驱机组因发电机尺寸随容量增加会成倍加大,对制造工艺及设备安装、运输、运行都提出了很高的要求,在各大风机厂商对单台容量陆续扩容的前提下,双馈机组必然是发展趋势。但双馈机组因先天高频轴电压对发电机及齿轮箱轴承的影响,制约了双馈异步发电机组的进一步发展。双馈机组向大容量、高技术方向发展,高频轴电压必须得到有效解决。     

Disease and destiny-mystery and mastery

When early people made their appearance, zoonotic infectious diseases were already waiting, but epidemic diseases did not appear in human history until people began to live in large numbers under conditions of close contact, mainly during the last 10,000 years. Disease has decimated urban populations, conquered armies, and disrupted society. The focus here is on (1) the plague of Athens and the Black Death; (2) smallpox, influenza, and rabies; (3) avian influenza prion diseases, and foot & mouth disease; and (4) emerging and re-emerging diseases. All have veterinary public health associations. In Athens, Greece, in 430 BC, when the Spartans ravaged the countryside, hordes crowded into Athens so that orderly movements, space in which to live, and adequate supplies of food became impossible. Crowding of any population fosters disease transmission; chaos and disorder enhance it all the more. Out of northern Egypt came a terrible plague from across the Mediterranean Sea. The identity of the plague of Athens remains unsure, but the well-considered conclusion is Rift Valley Fever, a mosquito borne, viral zoonosis. The Black Death, also called the Plague, raged in Asia for centuries. In 1347, the Black Death was brought by a ship out of Asia to Sicily. The scenes of devastation were repeated throughout Europe, with 90% or more of the people dying in city after city. Influenza, too, has been a cause of periodic human epidemics, but the great pandemic of influenza occurred in the last months of World War I. In the years of highest occurrence, more than half the world's population became clinically infected. If veterinary public health had been born earlier, it could have led to elucidating the epidemiology of influenza and the plagues of Athens, Europe, and Asia. In turn, smallpox had also caused continual tragedy. In 1796, Edward Jenner began to harvest pustules of cowpox from children or infected cows and inject them into susceptible children. In 1980, the World Health Organization declared that smallpox had been eliminated from the world. Rabies, though, still strikes terror. A number of animal diseases, broadly termed emerging and re-emerging diseases, need surveillance because they have the potential to impact human health. From late in 2003 to 2007, the highly pathogenic H5N1 influenza virus in poultry infected at least 121 people and caused 62 deaths in four countries. The prion diseases, too, all have very high numbers in concentrated contacts. To control these diseases, veterinary public health is essential, with diagnosis, epidemiological surveillance, clinical manifestations, and prevention as primary measures.     

Foot and mouth disease and bluetongue: differences and similarities

On 26th of july 2007 a new case of bluetongue was notified in the Netherlands and on 2nd of august 2007 foot-and-mouth disease was diagnosed in Surrey, England, which raised the threat of having both infections simultaniously in one area. Bluetongue and foot-and-mouth disease have a different pathogenesis, but symptoms may resemble each other at a later stage of infection. The pathogenesis and possible clinical symptoms of both infections are discussed and illustrated with pictures.     

德国荷兰畜禽产品质量安全交流与启示

2018年岁末,笔者有幸赴德国和荷兰,就畜产品质量安全控制及检测技术等进行了短期交流,收获颇丰,现具体介绍如下。一、交流情况德国面积35.73万平方千米,人口约8175.2万,是欧盟人口最多的国家,农业发达,机械化程度很高。德国的畜牧业以猪、牛、羊和禽类为主,畜牧业产值占农业生产总值的61%。德国虽然农业比重很小,但却是有机农业运动最早的发起国,也是目前世界上有机农产品生产与消费大国。     

奶牛肢蹄病及其防治

简介常见奶牛肢蹄病种类及其症状,从日粮营养、运动场地面结构、环境卫生、饲养管理、遗传育种、疾病管理等方面简析奶牛肢蹄病的病因,并提出相应的预防措施。     

畜禽物种多样性及其保护和利用

文章就我国畜禽物种多样性资源的现状、保护和利用等方面进行阐述,为生态脆弱的喀斯特地区畜牧业可持续发展提供参考。     

马的咽气癖及其防制措施研究进展

在动物的异常行为中以刻板行为最为常见,而咽气癖又是马最常见的口部刻板行为之一。作者就咽气癖在生理方面和心智方面对马体产生的影响、行为基础、诱因的研究进展及常见的防治措施进行综述。     

国内外蛋氨酸与赖氨酸市场分析与展望

近几年,世界饲用添加剂市场增长较快,预计今后将进一步增长,据世界粮农组织(FAO)首领会议的倡议,到2015年,将使世界营养不良的人口削减一半,其间,肉制品将会以每年2％的速度增长,特别是加快猪肉和禽肉增长。这将促进世界添加剂,尤其是蛋氨酸和赖氨酸需求量的增加。     

牛羊焦虫病诊断与防治技术

近几年来,辽宁省牛羊饲养业迅速发展,焦虫病的危害越来越明显,已成为危害牛羊的主要疾病之一。为了提高牛羊焦虫病的防治水平,保证我省牛羊饲养业的健康发展,笔者在参阅文献和同行们诊疗经验的基础上,结合自己的治疗实践,详细阐述了我省牛羊焦虫病近几年的流行特点和诊断防治方法。