350MW超临界直流锅炉水冷壁H型鳍片开裂失效分析

采用宏观形貌分析、化学成分分析、显微组织分析和数值模拟等方法对某电厂350MW超临界直流锅炉水冷壁H型鳍片开裂原因进行分析。分析结果表明,该锅炉水冷壁H型鳍片开裂的主要原因是鳍片较宽且厚度设计过小,致使鳍片不能被有效冷却而造成严重老化和脱碳,在交变热应力的作用下产生热疲劳而开裂。通过分析计算,确定了鳍片的合理厚度供参考。     

依靠可靠性管理提高机组稳定性

论述了发电设备可靠性在电力系统中的重大意义。借助可靠性管理对设备检修进行管理,为设备提供最佳的检修工期及最佳检修时间,并逐步完成由计划检修向状态检修过渡,及时根据设备情况提供有效的可靠性分析,为设备状态检修做出裁决,使设备真正做到“有病则医,无病运行”,在生产的全过程充分发挥可靠性管理的重要作用。     

Correction strategy of fuel injection quantity during pilot-main injection for common rail system

Journal of Mechanical Science and Technology - Common rail system is a key technology of energy saving and emission reduction for modern diesel engines. Multiple injection, as one of the most...     

含能催化复合纳米材料的制备研究

亚铬酸铜是促进复合固体推进剂中高氯酸铵分解的一种很好的催化剂,但由于以往制备的亚铬酸铜及高氯酸铵超细微粒易发生团聚,不能有效地对高氯酸铵的分解起催化作用。本文使用高能球磨法,使纳米级亚铬酸铜嵌入或粘附于高氯酸铵晶体表面而形成复合粒子,因而大大地提高了对高氯酸铵的催化效果,使高氯酸铵的热分解反应温度区间明显前移,热分解反应的激烈程度大大提高     

分布式实时数据库在输变电系统中的应用

本论文主要对分布式实时数据在输变电系统中各项事务管理和数据汇总处理等应用进行阐述.首先介绍了分布式实时数据库及其特点,接着,详细介绍了分布式实时数据库在输变电系统中的应用.分布式实时数据库的建立可以实现对国网山西省电力公司检修公司所有事务的处理和对所运营的各地区的变电站实时数据进行汇总和处理,同时为智能变电站网络管理系统的建立提供知识库数据和专家经验.为变电站的联网运行奠定基础.     

A Delay-Dependent Approach to Robust H ∞ Control for Uncertain Stochastic Systems with State and Input Delays

In this paper, the problem of delay-dependent robust H _∞ control for uncertain stochastic systems with state and input delays is investigated. The time delays are assumed to be bounded and time varying and the uncertainties are assumed to be norm bounded. By using the Lyapunov functional method, a new delay-dependent robust H _∞ control scheme is presented in terms of linear matrix inequalities (LMIs). Some numerical examples are given to illustrate the effectiveness of the proposed approach. This work is partially supported by the Natural Science Foundation of China (60674055, 60774047), and the Taishan Scholar Programme of Shandong Province. An erratum to this article can be found at     

用小波矩阵分析法进行函数的分解与重构

就傅氏级数和小波变换之间的关系进行较全面地讨论。并采用小波矩阵分析方法,使小波变换本质跃然于纸上。同时给出小波分解和小波重构的计算公式,应用变得十分容易。     

On scheduling all-to-all personalized connection and cost-effectivedesigns in WDM rings

We consider the problem of scheduling all-to-all personalized connections (AAPC) in WDM rings. Scheduling one connection for every source-destination pair in a network of limited connectivity provides a way to reduce routing control and guarantee throughput. For a given number of wavelengths K and a given number of transceivers per node T, we first determine the lower bound (LB) on the schedule length, which depends on both K and T. To achieve the LB, either the network bandwidth, the I/O capacity, or both should be fully utilized. This approach first constructs and then schedules circles, each of which is formed by up to four non-overlapping connections and can fully utilize the bandwidth of one wavelength. The proposed circle construction and scheduling algorithms can achieve the LB if K⩽T相似文献   

高压大容量变频技术现状及交——交SDM级联技术简介

本文通过对目前广泛使用的三电平及多电平级联高压变频控制方案技术特点的对比论述，介绍了一种新型高压大容量变频器控制方案，并对该方案的优越性作了介绍。