水轮发电机冷却风机变频控制系统的设计

讲述基于PLC的PID控制算法的水轮发电机冷却风机变频控制系统。系统主要应用于灯泡贯流式水轮发电机组,使得灯泡贯流机组冷却温度恰当,既节能又兼顾发电效率和发电机寿命。     

低风速风电机组电刷滑环故障仿真分析研究

电刷滑环是低风速风电机组转动部件的核心设备之一,它的可靠稳定是风场安全运行的重要保证。目前国内外关于低风速风机电刷滑环的研究相对较少。实践证明,滑环和电刷的表面受污、表面不光滑、电刷压力不够、接触面不平整等因素会导致滑环与电刷间接触不良,使接触电阻增大。滑环异常磨损会造成发电机故障停运,很大程度上影响了风场的安全生产和经济效益。因此开展风机电刷滑环故障分析的研究意义深远。文中对风机电刷滑环故障进行诊断研究,基于ANSYS软件对低风速风电机组的电刷滑环在正常状态下和故障状态时进行仿真分析,从而确定出故障初期,可以进行及时的维修,具有一定的工程应用价值。     

灯泡贯流式水轮发电机制造工艺慨述

针对灯泡贯流式水轮发电机独特的结构,简要介绍泡头、机座、转子支架制造,贴壁结构定子铁心的定位筋安装,推力环加工,组合轴承预装和定、转子绕组制造等所采取的工艺措施,为制造灯泡贯流式水轮发电机提供参考。     

灯泡贯流式机组导水叶开度不均匀的简易检测及处理

使用简易检测方法,找出了灯泡贯流式水轮发电机组长期运行后因导水叶及其传动机构变形引起导水叶开度不均匀、机组振动及噪音过大的原因,并提出了简易有效的处理方法,可供相关人员参考。     

水轮发电机转子支架有限元分析及应力试验

对某水电站灯泡贯流式水轮发电机转子支架进行有限元分析,通过分析发现转子支架原设计的不足,为此对水轮发电机转子辐板进行了动态应力测试,结果与分析数据相吻合,为转子支架的改进设计提供了依据.     

GZ103—WP—275型灯泡贯流式水轮发电机组Ⅰ号机组投入运行

重庆水轮机厂为江津县贾嗣区五福电站设计和制造的GZ103—WP—275型灯泡贯流式水轮发电机组是开发低水头大流量水力资源的水轮发电机组,于1978年3月投入运行以来,已为国家提供了400多万度电,为我国高速度发展农业机械化和电气化,作出了贡献。一、机组基本参数     

京南电站灯泡贯流式机组运行中存在问题分析及处理方法

介绍了灯泡贯流式机组的特点与优点，概述了京南电站的情况，分析了其使用的灯泡贯流式机组在10多年运行过程中存在的问题，并提出了处理方法。     

水电站灯泡贯流式机组受油器结构改造研究

受油器是双调节水轮发电机组的重要设备之一,在运行中可优化设备效率,合理利用水力资源,充分发挥与导水机构的协联作用,对产生最大经济效益的操作系统起关键性作用。现对龙王台水电站灯泡贯流式机组受油器故障及其原因进行分析,并应用新型受油器进行机组改造,结果表明,新型受油器运行稳定,故障发生率低,安全效益、经济效益显著。     

国外轴伸贯流式水轮机概况

贯流式水轮机按其结构和布置方式,通常分为灯泡贯流式、竖井贯流式和轴伸贯流式三大类。本文主要介绍国外轴伸贯流式机组。一、国外轴伸式机组概况轴伸贯流式机组由于有较长的主轴穿过尾水管或进水弯管,使整个流道弯曲,从而影响水轮机效率降低,这对于大型机组是不合适的。但对于中、小型机组,特别是小型机组,由于发电机置于流道外,没有特殊要求,故可以采用普通的发电     

阔克塔勒电站灯泡贯流式水轮机的设计

阔克塔勒电站水轮机转轮直径3.4 m,属于小型灯泡贯流式机组。文章在常规贯流式机组设计的基础上,从运行、制造、安装方面考虑,对阔克塔勒水轮机机组结构进行了优化和改进,为贯流式机组的结构设计提供参考。     

Chemical factors in carbon brush wear

Chemical factors involved in the wear of carbon brushes on metal slip rings are discussed. Under conditions of elevated temperature operation in an oxidizing atmosphere, a correlation is found between the oxidation characteristics and the wear rates of carbon brushes. It is demonstrated that temperatures in the oxidation range can readily be generated by current converging through high resistance constrictions in the contact zone. Copper and other metals present in the slip ring can act as catalysts for the oxidation, the metal oxide particles migrating into the interior of the brush and causing enhanced gasification rates and increased porosity. Treatment of the brush with oxidation inhibitors, such as phosphorus oxychloride, and surface alloying of the ring with non-catalytic materials, such as zinc, can reduce the wear rate at elevated temperatures under favorable conditions. Graphite surfaces are also attacked by reactive gaseous species such as atomic nitrogen and oxygen, ozone and nitrogen oxides which may form near the brush surface during arcing.     

贯流泵装置能量特性试验研究

结合淮河入海水道工程妇女河泵站，对贯流泵装置能量特性进行了试验研究。试验分别对前、后置灯泡贯流泵装置型式进行能量试验。试验表明，前置灯泡贯流泵装置型式比后置灯泡贯流泵装置型式有较好的水力性能，其最高效率比后者提高5％左右，最优装置效率达到72％。     

某星载滑环的可靠性设计与试验

滑环是卫星的关键件,可靠性要求非常高,某卫星滑环采用盘式滑环方案取得成功。文中介绍了盘式滑环的技术特点、适用场合,冗余设计、降额设计、结构设计、热设计等可靠性设计方法的应用,以及为满足高可靠、长寿命在材料级和单机级所进行的验证试验。     

Thermoelastic effects in brushes with high current and high sliding speeds

Experimental results in the literature indicate that electric brushes may deform thermally, leading to point contact with the slip ring at high current levels. The present work provides theoretical support for these observations and a quantitative statement showing how operating variables influence this behavior. The analysis is restricted to a two-dimensional model of the brush with isotropic and constant material properties. The most unexpected result is that for steady current flow cooling of the exterior of the brush increases the tendency to deform unfavorably.     

Electric current effects in wear phenomena at a rotating Cu-Ag interface

Two silver wire brushes were held in contact with a rotating copper slip ring in an ultrahigh vacuum system. After initial sputter cleaning of the copper slip ring, the vacuum system was backfilled with humidified CO₂ to a pressure of 1 atm. A d.c. electric current was passed across the silver brushcopper slip ring-silver brush assembly and the resulting wear particles were analyzed using scanning electron microscopy and electron probe microanalysis. The slip ring surface was analyzed using Auger electron spectroscopy to determine the amount of silver transferred. Currents ranging from 0 to 50 A were used. In each case the numbers of pure copper, pure silver, copper-rich and silver-rich particles were recorded as a function of the current. The Auger signal from the slip ring and the concentrations of the elements in the wear debris were plotted versus the current to determine the role of current in the present Cu-Ag system.     

灯泡贯流机组受油器泄漏的处理

锦江电力开发总公司的六台国产灯泡贯流机组受油器漏油严重，通过分析其密封结构和产生泄漏的原因后，对受油器浮动轴套进行改造，漏油处理成功。     

汽轮发电机端部绕组鼻端引水线的电磁力与固有特性

依据麦克斯威尔方程，并采用分离变量法，给出大型汽轮发电机运行时定子端部鼻端处磁场分布的表达式。在此基础上，根据洛仑兹力的表达式和简化的模型，得到鼻端空心绕组引水线所受电磁力的计算式。运用有限元方法，对给出不同设计方案下的力学模型，分析鼻端空心绕组引水线的固有振动特性，并给出固有振动的各阶频率值和相应的振型图。通过得到的固有振动频率值，并与电磁力激发的强迫振动频率值进行比较，对不同情况下鼻端引水线在运行时的安全性进行一定的分析。     

Photoelastic visualization of contact phenomena between real tribological surfaces, with and without sliding

The design, construction and operation of a machine for visualizing real contact interfaces and testing sliding wear is described. The bodies that form the interface are both opaque—the slider is a carbon graphite sample (National Electrical Carbon Company brush grade 634) and the rotor surface is copper. The visualization technique uses contact indentation stresses and photoelasticity to generate optical fringes (shadows) directly beneath the contact interface. The resultant fringes indicate the size and location of the islands of real contact that exist within the apparent contact region. Resolution is sufficient to distinguish two neighbouring millimetre-sized contacts. For calibration and comparison purposes, photoelastic pictures of sharp graphite pencil points and hard plastic spheres of various diameter indenting the copper slip ring surface are presented. Photographs of photoelastic images of contact interfaces between an opaque carbon sample sliding against an opaque copper slip ring are also presented. Photographs are presented that show the formation of concentrated contact (and possible evolution to thermal mounding) on the carbon slider surface. Collective data from other photographs measures the relative occurrence of concentrated contact and suggests operating and surface conditions that can discourage concentrated contact and formation of thermal mounds.     

ADAMS/View环境下的涡旋压缩机动态仿真设计

针对某型涡旋压缩机,在ADAMS/View环境下建立了虚拟样机仿真模型。通过ANSYS平台生成模态中性文件（MNF文件）,实现了曲轴、动涡盘及十字滑环的柔性化设计,创建了涡旋压缩机的刚柔耦合模型。在柔性体动力学仿真基础上,分析了涡旋齿的啮合规律,明确了曲轴与十字滑环的运动状态,并计算出了主轴系统在启动阶段更为精确的速度、加速度变化规律,指出：主轴启动0.3 s后,涡旋压缩机趋于稳定运行。动态仿真结果为涡旋压缩机的技术进步提供了重要参考和依据。