无键锥度液压联接在大功率高转速偶合器中的应用

带有增速齿轮传动的偶合器在电站中广泛应用,其传动齿轮与轴之间的可靠联接,不仅能提高偶合器的承载能力、简化加工工艺、节约原材料、降低安装难度,更增加了给水泵机组安全运行的可靠性。阐述了国内外大型火电机组锅炉给水泵组配置现状,对带增速齿轮的调速型偶合器的两种偶合方式进行了技术分析,介绍了无键锥度液压联接耦合器的设计,并以具体实际案例说明所得出的方法应用于300MW等多种类型的汽轮机给水泵液力耦合器的设计。     

液偶调速电动机给水泵变频改造方案及节能潜力分析

文中围绕宁夏国华宁东发电有限公司的330 MW机组上应用的锅炉液力偶合器调速电动给水泵组的变频改造方案进行了介绍,并对液偶调速电动机给水泵变频改造方案的节能潜力进行了分析。     

液偶调速电动给水泵节能改造方案解析——行星齿轮变矩调速器与变频器方案对比

当前火力发电厂锅炉给水泵普遍采用液力偶合器作为调节装置,但是由于液力偶合器的机械结构和调节方式的限制,液力偶合器调节方式存在效率较低和可调范围较小等不足,随着科技发展和技术创新,多种新型调节装置可用于锅炉给水泵调节。介绍了行星齿轮变矩调速器(VORECON)与变频器(VFD)两种新型调节装置的原理、性能、改造方案和费用,通过实际改造案例详细对比了两种方案的改造后实际效果和费用,得出变频器改造方案优于行星齿轮变矩调速器方案的结论。     

应用液力偶合器提高工矿企业节能的经济效果

<正> 在冶金、矿山、电站、起重运输、石油化工、工程机械等行业的技术改造中,应用液力偶合器对节约能源和延长动力机械使用寿命具有显著的效果。大连液力机械厂生产的GST50调速型液力偶合器,于1981年四季度在南京热电厂五号机组锅炉给水泵上安装使用后,可根据用电峰值变化调整水泵转速,改变锅炉供水量,每天平均可节电4000度以上,一年(按运转300天     

电站锅炉给水泵节能改造

介绍了滦河发电厂针对锅炉给水调节门节流损失严重的问题 ,提出了液力偶合器变速调节、电机变频调节、小汽轮机变速驱动三种改造方案 ,通过技术经济性对比 ,确定选用液力偶合器变速调节 ,经济性分析和实际运行效果都表明了中、小型机组采用液力偶合器变速调节锅炉给水泵是经济可行的。     

锅炉高压给水泵液力偶合器调速的特性分析

目前,锅炉高压给水泵广泛采用液力偶合器调速来实现流量调节,具有明显的节能效益。 (一) 在叙述叶片泵(或风机)采用液力偶合器传动(以下简称偶合器)调速进行流量调节时,一般都假定其动力特性为M_z∞n_z~2(或N_z∞n_z~8,角标“Z”表示它们是传动     

某供热机组锅炉给水泵液偶改变频调速汽蚀安全性分析

文中对某2×300 MW及2×330 MW供热机组锅炉给水泵液力偶合器改变频器调速方案进行了现场调研,计算了变频改造后各种工况下除氧器至给水泵入口段的管路损失,并结合前置泵的运行数据对给水泵入口有效汽蚀余量和必须汽蚀余量进行了校核计算。结果表明:变频改造后,其前置泵转速在1 000~1 490 r/min范围内变化时,给水泵组入口有效汽蚀余量均大于其必需汽蚀余量。该改造方案能够满足给水泵组汽蚀安全性要求。     

锅炉引风机采用变速调节技术

锅炉引风机采用液力偶合器进行变速调节，不但取得了较好节能效果，而且延长了电机和引风机的寿命。液力偶合器结构简单、运行可靠、维护量少。经过长期运行实践证明，锅炉引风机采用液力偶合器进行调节是可行的。     

给水泵液力调速系统的特性及其非线性改善方法分析

在对液力偶合器调节给水泵转速系统的调节特性做了分析之后,介绍了用以改善调节特性严重非线性的可变函数发生器的原理及软,硬件设计方法,通过试验分析提出了改进大功率调速型液力偶合器的勺管驱动方法。     

锅炉电动给水泵调节特性的线性化分析

火电厂的电动锅炉给水泵一般都以调速型液力偶合器作为传动装置,用以实现给水泵的转速调节和泵的流量控制,其调节特性的线性化对系统自动化控制的质量有很大影响.用“可变函数发生器”微机系统实现调节特性的线性化校正是一种先进技术.本文研究了由锅炉系统中蒸汽压力造成的给水系统净扬程对上述调节特性线性化处理的影响以及这种影响的分析方法.图8参4     

耦合热泵技术的地热能利用研究

介绍耦合热泵技术的地热能利用新思路,探讨地热与热泵技术耦合利用的形式,分析耦合热泵技术的地热能利用的优势,热泵技术与地热耦合利用中存在的问题,以及耦合热泵技术的地热能利用前景等,最后简要介绍了一种以地热能为驱动力的家用热泵的结构和工作原理。     

一类多变量控制系统的解耦控制

该文提出在静态增益系数评价多变量控制耦合程度的基础上 ,增加动态耦合度和静态交叉耦合率二个概念 ,能更全面地评价多变量控制系统的耦合程度。对于 2× 2多变量控制系统 ,按系数正、负号的个数分为奇耦合和偶耦合 ,并证明奇耦合系统都能用解耦方法改善控制品质 ,同时给出解耦控制的计算方法。该方法可在电站控制系统得到广泛的应用。图 3参 6     

The multiscale thermal-hydraulic simulation for nuclear reactors: A classification of the coupling approaches and a review of the coupled codes

Simulation is becoming increasingly important in the safety analysis of nuclear reactors nowadays. The physical phenomena in a nuclear power plant happen on three classified scales: system scale (phenomenon over the whole plant is concerned), component scale (phenomenon in specific component is concerned), and mesoscale (phenomenon in a small part of a component is concerned). Owing to the particular emphases, various codes are developed to simulate particular problems. System codes intend to predict the behavior of the whole power plant during normal or accidental phases (system scale). Subchannel codes are for core behavior predictions (component scale). CFD codes can simulate the thermal-hydraulic in a fixed part of the plant (mesoscale). Those codes are coupled together to better predict the conditions in a nuclear reactor in last the two decades, which is the multiscale thermal-hydraulic simulation approach for nuclear power systems. Diverse coupling approaches are developed and various coupling codes are implemented. This paper first proposes a classification of those approaches. It tells that a multiscale coupling is composed of five items: coupling architecture, operation mode, domain coupling, field mapping, and temporal coupling. Numbers of options are available for each item. For coupling architecture, it can be internal coupling, via-IO coupling, server-client, or serverless coupling. For operation mode, it can be either parallel or serial. For domain coupling, it can be either domain-decomposition or domain-overlapping coupling. For field mapping, it can be manual-definition, processed by user-developing toolkit, or handled by third-party libraries. For temporal coupling, it can be explicit coupling, semi-implicit coupling, or implicit coupling. An evaluation of the approaches is performed based on new-proposed criterion. A general review of the multiscale thermal-hydraulic coupled codes is made based on the classification. Especially, a review of the domain-overlapping approach is present considering it is the most promising but challenging method for multiscale thermal-hydraulic simulation.     

挠性联轴器性能分析

列举并比较了国内外动力传动装置中应用的各种具有代表性的挠性联轴器,通过对其性能的综合分析,为用户在选用此一类产品时提供了参考。     

工业汽轮机振动故障分析与处理

燕山铜铁公司2号高炉送风机的拖动系统由电机拖动改为汽轮机拖动后,由于管道;中洗油质太脏导致启动不顺利,处理后发生联轴器长度设计不合理导致风机振动大;更改联轴器长度后,经过现场动平衡和调整高调机构间隙后,机组整体运行状态良好。     

Dynamic modeling and experimental validation for the electrical coupling in a 5-cell solid oxide fuel cell stack in the perspective of thermal coupling

The electrical coupling in a 5-cell solid oxide fuel cell (SOFC) stack is investigated in this research. The electrical characteristics tests of a single cell and the stack were performed in an electrical furnace. It was found that the single cell with the highest temperature does not give the highest output voltage in the stack test, which is different from the result that the output voltage increases with temperature in the single cell test. A physical interpretation for this phenomenon is given specifically from the standpoint of electrical coupling on the basis of thermal coupling between cells in the stack. Furthermore, a system level electrical coupling dynamic model is developed to characterize the electrical characteristics of the stack by considering the contact resistance between cells. In addition, the electrical coupling dynamic model is calibrated and validated based on the experimental data. The results demonstrate that the electrical coupling dynamic model can depict and predict accurately the electrical characteristics of SOFC stacks. The accurate electrical coupling dynamic model is important for the system level study of SOFCs, such as the optimization of stack structures and the design of peripheral control systems.     

LS1210型高弹性联轴器疲劳寿命预测

为降低高弹性联轴器疲劳寿命研究成本及缩短其开发周期,基于一型广泛应用的成熟产品,通过FE-SAFE/ABAQUS联合仿真预测其疲劳寿命,并以实际使用寿命来验证疲劳寿命预测的可靠性。首先通过橡胶材料的单轴拉伸、平面拉伸力学试验拟合出能准确描述其力学性能的二次多项式本构模型,计算获得了该产品橡胶块在工作载荷下的应力、应变分布,最后通过疲劳寿命分析,得出了该产品无限寿命的结论,这与其实际使用寿命相符合。表明该疲劳寿命预测方法切实可行,并可用于同类产品的设计、开发。     

渗流影响下坝体和岩基应力场的分析模型研究

用等效面力和体力代替渗流影响下引起的湿胀效应的计算表达式,提出了数值分析法模拟湿胀效应的加载方法．此外,还提出了考虑坝体湿胀影响下的坝基应力场与渗流场的耦合分析模型,研制了相应的有限元分析程序．由实例分析了不同方法计算渗流影响时对岩基稳定的效应,并得出了在考虑应力场与渗流场耦合作用下,其计算成果更接近实际的结论．     

300MW汽轮机低压缸末级长叶片与轴系扭振的耦合振动

计算分析了３００ＭＷ汽轮机低压缸末级长叶片Ａ０振型弯曲振动与轴系扭振耦合对叶片安全性的影响。末级长叶片与轴系扭振耦合将使该叶片振动的实际频率避开率低于计算值,当发生严重的两相短路故障时在叶片根部的最大动弯矩远远高出其额定值;如果电网频率偏离５０Ｈｚ,会对叶片安全性产生更为不利的影响。     

A preliminary assessment of the market coupling arrangement on the Kontek cable

This paper presents a preliminary assessment of the market coupling arrangement on the Kontek (KT) cable between East Denmark and Germany and an assessment of the original auction mechanism. KT, the new spot price area, was introduced in Germany on October 5, 2005 to facilitate a market coupling arrangement on the KT cable between East Denmark and Germany. We would expect the KT price to correlate more with the European Energy Exchange (EEX) price because arbitrage normally levelizes the price. However, spot prices in late 2005 were both high and volatile because congestion management practices in Sweden transferred internal bottlenecks to the cable between Sweden and East Denmark. Since spot prices were equal in East Denmark and the KT area for a substantial time, it implies that some hours had no congestion on the KT cable. Market players valued the previous monthly auctions for transmission capacity more than the daily auctions. Compared to the daily auctions, market players received smaller payoffs on average for the market coupling arrangement, and the smallest payoffs for the monthly auctions.