循环流化床锅炉脱硫的工艺试验及模型预测

通过在７５ｔ／ｈ循环流化床锅炉上所进行的试验研究,取得了加石灰石脱硫的动态特性。依据循环流化床脱炉运行特点,对原有的循环流化床锅炉脱硫模型进行了部分改进,成为已建的循环流化床锅炉总体数学模型的一个子模型。运用该模型对循环流化床锅炉炉内ＳＯ２的生成和脱除进行模拟,模拟结果与工业试验结果吻合。模拟结果还揭示了加石灰石脱硫对循环流化床锅炉运行的影响。     

提高循环流化床锅炉炉内脱硫效率的技术探讨

石灰石在850～900℃的温度范围内可充分发生煅烧和脱硫反应，循环流化床锅炉炉膛内燃烧温度与石灰石脱硫温度契合，可在炉内形成脱硫反应，达到廉价脱硫的目的。循环流化床锅炉炉内脱硫反应与床温控制、石灰石粒径、石灰石给入均匀性、反应时间等因素有关。分析了循环流化床锅炉炉内脱硫效率的影响因素，论述了提高炉内脱硫效率的关键技术。     

循环流化床锅炉脱硫的工业试验及模型预测

通过在７５ｔ／ｈ循环流化床锅炉上所进行的试验研究,取得了加石灰石脱硫的动态特性。依据循环流化床锅炉运行特点,对原有的循环流化床锅炉脱硫模型进行了部分改进,成为已建的循环流化床锅炉总体数学模型的一个子模型。运用该模型对循环流化床锅炉炉内ＳＯ２的生成和脱除进行模拟,模拟结果与工业试验结果吻合。模拟结果还揭示了加石灰石脱硫对循环流化床锅炉运行的影响。     

炉内石灰石脱硫技术在大型循环流化床锅炉的应用

结合华能白山煤矸石发电公司的2×330MW循环流化床锅炉空冷机组炉内石灰石添加系统的改造,论述了循环流化床(CFB)锅炉的燃烧特性、炉内石灰石脱硫机理、影响CFB锅炉脱硫效率的因素以及炉内脱硫对脱硝的影响等。石灰石添加系统改造后提高了石灰石投入的稳定性,保证锅炉连续稳定脱硫,烟气排放达到环保要求。     

260 t/h循环流化床锅炉脱硫系统若干问题的分析与研究

目前已运行循环流化床(CFB)锅炉,特别是220 t/h以上的CFB锅炉对炉内脱硫系统的运行经验不足,文章针对福建无烟煤的燃烧特性,经过对石灰石脱硫系统的运行调试,探讨CFB锅炉炉内脱硫中涉及的若干问题,分析脱硫影响因素及添加石灰石对锅炉的影响。同时希望石灰石脱硫技术能在同炉型循环流化床电厂中得到更多推广应用,使循环流化床锅炉清洁燃烧的优点得以更好体现。     

循环流化床锅炉高效炉内脱硫技术研究与应用

分析了目前循环流化床锅炉炉内脱硫技术存在的问题及原因,介绍了石灰石反应活性分析评价方法、石灰石输送系统的设计、调试及运行优化技术的研究工作,简述了循环流化床锅炉高效炉内脱硫技术工程应用实例,研究结果可供同类CFB锅炉机组借鉴.     

200MW循环流化床锅炉电石渣炉内脱硫影响研究

使用电石渣替代石灰石进行循环流化床锅炉炉内脱硫,一方面可以实现废弃物的资源化利用,另一方面能够有效降低脱硫成本.计算电石渣脱硫对200 MW循环流化床锅炉热效率影响,并与石灰石脱硫进行比较,结果显示电石渣的性能指标优于石灰石.     

1025t／h循环流化床锅炉深度脱硫方式选择研究

介绍了国外循环流化床锅炉+尾部烟气脱硫技术的现状以及尾部脱硫方式的选择原则.通过对湿式石灰石/石膏法、烟气循环流化床干法、旋转喷雾半干法、炉内喷钙--尾部加湿活化法以及单纯炉内喷钙法等几种主要烟气脱硫工艺的分析比较,得出循环流化床锅炉炉内一级脱硫+尾部增湿活化二级脱硫是大型循环流化床锅炉深度脱硫的合理方式,该方式脱硫效率高,成本低,环境效益好,而且简易可行.     

循环流化床锅炉热效率计算方法探讨

以炉内直接加入石灰石进行脱硫的循环流化床锅炉为对象 ,基于GB10 184- 88,结合内江电厂锅炉性能试验的实践 ,参考国外脱硫计算方法 ,探讨修订在燃烧室直接加入石灰石脱硫的流化床锅炉的热效率计算方法     

循环流化床锅炉脱硫问题分析

简要说明了循环流化床锅炉炉内脱硫机理,对循环流化床锅炉加钙脱硫在实际运行中存在的问题和影响脱硫率的主要因素进行分析,多方面寻求解决问题的对策,以提高循环流化床锅炉脱硫效率,促进环境空气质量的改善。对如何提高循环流化床锅炉脱硫率提出建议。     

A framework for constructing databases for supervisory control systems

This paper presents a framework for constructing databases for supervisory control systems. The proposed framework utilizes a generation-based approach and object-oriented framework libraries. In this framework, a database is designed for the target system from a design template, and the software for the database system is generated from the database design. The generated database system includes a domain-specific object system and a diagram and plant data editor, which provides effective data input functions. © 1998 Scripta Technica, Electr Eng Jpn, 123(1): 32–42, 1998     

IEEE Standard for Synchrophasors for Power Systems

IEEE Standard 1344, Synchrophasors for Power Systems, was completed in 1995. It sets parameters required to ensure that phasor measurement will be made and communicated in a consistent manner. It specifies requirements for the timing signal used for phasor synchronization and the time code needed for input to a measurement unit. GPS is the recommended time source and IRIG-B is the basic format used for time communication. The standard requires correlating phasors computed from unsynchronized and synchronized sampling to a common basis. Timetagging accurately and consistently is essential for wide area comparison of phase. The standard specifies information exchange and control message formats. These include data output, configuration, and command messages. It includes 7 annexes that discuss the concepts covered in the body of the standard     

Three-Stage Method for Selecting Informative Genes for Cancer Classification

Gene expression data produced by microarray machines are useful for cancer classification. However, the process of gene selection for the classification faces a major problem because of the properties of the data such as the small number of samples compared with the huge number of genes (high-dimensional data), irrelevant genes, and noisy data. Hence, this paper proposes a three-stage method to select a small subset of informative genes which is most relevant for the cancer classification. It has three stages: (i) pre-selecting genes using a filter method to produce a subset of genes; (ii) optimizing the gene subset using a multi-objective hybrid method to yield near-optimal subsets of genes; (iii) analyzing the frequency of appearance of each gene in the different near-optimal gene subsets to produce a small (final) subset of informative genes. Five gene expression data sets are used to test the effectiveness of the proposed method. Experimental results show that the performance of the proposed method is superior to other experimental methods and related previous works. A list of informative genes in the final gene subset is also presented for biological usage. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

对转永磁同步推进电动机的矢量控制

为了实现水下大功率和高效率电力推进,介绍了对转永磁同步推进电动机的结构和工作原理。推导了其数学模型和电磁关系,建立了该电机的M atlab仿真模型;研究了对转永磁同步推进电动机的矢量控制原理,建立了该电机的矢量控制系统,设计了双转子在推进器扰动下的转速跟随方案,并进行了仿真。仿真结果与理论分析相吻合,验证了模型的有效性,说明了矢量控制技术可以实现对转永磁同步推进电动机的调速。     

直流电子式电流互感器中的一种谐波测量新方法

直流线路中谐波的测量对于谐波的抑制和治理具有重要的意义。为此,介绍了一种新型的300A直流电子式电流互感器(ECT)的谐波测量方法。该方法采用自积分式的带铁氧体铁心的Rogowski线圈,既克服了传统线圈受直流偏移影响严重的缺点,又避免了空心Rogowski线圈在小信号时灵敏度低的不足。实验结果证明该线圈在满足准确度要求的条件下可忽略直流分量对于磁导率的影响。同时,在实验室条件下,对线圈及积分电路的线性度、频率特性和温度特性进行了评估,实验结果显示该系统可以对50～2500Hz频段的谐波进行准确测量。系统线性度良好,准确度达到1%,并能在-30～70℃的温度变化范围内稳定工作,满足公用电网电能质量谐波GB/T14549-1993的要求。     

An annual framework for clustering-based pricing for an electricity retailer

In the competitive environment, it is necessary for a retailer to increase his/her profit as much as possible. There are few researches focused on the subjects related to the retailer and the retail market. In addition, those researches have mostly focused on the participation of the retailer in the wholesale market. In order to determine the optimal selling price, the knowledge of how and when consumers use electricity is essential to the retailer. This type of information can be found in load profiles of customers. In this paper, an annual framework for optimal price offering by a retailer is proposed which is based on clustering technique. For this purpose, load profiles of customers are used as their consumption patterns. Also, a profit function is defined as the objective of optimization problem based on the load profile considering conditional value at risk (CVaR) for risk modeling. Also, a new acceptance function is proposed to overcome drawbacks of the traditional ones. The objective function is a mixed-integer nonlinear problem which is solved by GAMS software.     

Design principles for a flywheel energy store for road vehicles

This paper introduces a flywheel energy storage device capable of enhancing the fuel economy of a hybrid-type road vehicle. A number of possible drive types are considered and the permanent magnet machine drive is shown to provide the best solution. Reasons for selecting a device using an axial-field configuration with single-rotor and double-stator sections are described. Electrical, magnetic, and mechanical design data are presented for a full-scale prototype device with 240 kJ of usable energy storage and 25 kW of power transfer, operating at speeds up to 50 000 r/min, with a 10% duty cycle     

New Algorithms for Computer Relaying for Power Transmission Lines

Synopsis

This paper presents a new recursive discrete-time filter for calculating the impedance from digitized voltage and current samples from the relay location, The transmission line voltage and current signals during a fault are modelled as a sum of decaying dc, and components of fundamental frequency and higher harmonic frequency components. The recursive discrete-time filter interpolates the signal samples and generates filter coefficiencs either by using spectral observation or functional expansion techniques. Both the algorithms are tested by using the fault data recorded at the Saskatchewan Power Corporation producing fast and reliable tripping conditions.     

电力勘察设计企业数据仓库的架构方式

电力勘察设计企业的信息化经过多年的发展建设,已积累了大量面向应用的数据,亟需建立一个能满足综合需求、提供多个层面的分析数据的数据仓库中心.从数据仓库的概念和2种不同的数据仓库体系结构探讨了适合电力勘察设计企业的数据仓库架构方式.     

校验用开合式霍尔电流传感器聚磁环设计

对电流互感器进行在线校验符合电力系统供电可靠性的要求,针对一般闭环霍尔电流传感器磁环只开一段气隙的情况,文中介绍了一种可用于在线校验的开合式聚磁环结构霍尔电流传感器.以提升测量精度和灵敏度为目的 ,从磁环材料的选择、磁环横截面积大小以及气隙长度等方面阐述了设计方法,具体探讨了两段气隙总宽度与磁环总长度的比例关系.利用C...