基于模糊隶属度的电力设备资产全寿命周期成本模型及评价体系研究

电网企业将LCC理论应用作为提高设备资产效率和质量的有效手段,亟需解决LCC应用中的模型计算和评价体系问题.本文通过构建电网企业资产全寿命周期管理机制,建立了电力设备的LCC的计算模型和方法,采用基于模糊数学中的模糊隶属度方法,改进了技改和大修项目分摊到多个设备资产分摊方法,提出了电力设备的LCC评价模型和评价体系,并...     

On combination of the equivalent material concept and J‐integral criterion for ductile failure prediction of U‐notches subjected to tension

The aim of the present research is to check the capability of the equivalent material concept (EMC) combined with the J‐integral failure criterion, called EMC‐J criterion, in predicting the load‐carrying capacity (LCC) of U‐notched ductile aluminium plates subjected to tension by considering the 2 moderate and large‐scale yielding regimes. For this purpose, first, a set of experimental results on LCC of 2 groups of thin U‐notched rectangular plates made of Al 7075‐T6 and Al 6061‐T6 are gathered from the recent literature. Then, because the Al 7075‐T6 and Al 6061‐T6 plates have ductile behaviour, EMC is employed to avoid performing elastic‐plastic failure analysis for LCC predictions. Up to now, different failure models in the context of the linear‐elastic notch fracture mechanics have been successfully utilized in combination with EMC for ductile failure prediction of notched members. However, this is the first time in this research that J‐integral, as a well‐known brittle failure criterion, is linked to EMC for predicting LCC of the U‐notched rectangular aluminium plates. Finally, it is shown that EMC‐J criterion can predict well the experimental results of tensile LCC.     

基于可视化程序设计语言的编译系统

采用面向对象技术设计可视化程序设计语言的编译系统,通过对复杂的可视化图片语法进行分析,将各语法现象以语法单元类的形式进行抽象分类,提出了编译器－编译器的设计策略,给出了从可视化图片设计语言到伪指令代码的解决方法。主要研究在面向对象的编辑环境中如何实现满足硬件设备控制器的稳定、高效的编译系统。通过将可视化程序语言分析器(VPLPG)和小型的类C编译(LCC)器配合使用最终实现可视化程序设计语言的编译系统。     

全寿命周期成本(LCC)理论在电能表管理中的应用

分析了电能表管理工作中存在的一些问题,介绍了LCC（全寿命周期成本）概念、构成及管理,着重分析了电能表的LCC构成,并对几种单相电能表的LCC进行了计算和分析。阐述了LCC理论在电能表管理中的应用。     

兼顾供电可靠性和LCC的变电站主设备检修策略优化方法

提出了一种能够同时兼顾变电站供电可靠性和设备全寿命周期成本(LCC)的设备检修决策优化方法。该方法选择变电站中的待检变压器和断路器,利用健康指数(HI)和役龄回退因子分别计算待检设备检修前后的故障率;通过变电站的预想事故分析和负荷削减状态的枚举,计算设备检修前后变电站电量不足期望(EENS)和设备LCC的变化量;最后,分别给出以可靠性优先、经济性优先和费效比优先作为评价指标的优化检修策略。某220kV变电站的检修决策实例表明,该方法能够综合考虑变电站的供电可靠性和设备的LCC,制定合理有效的检修策略。在有效降低变电站供电风险的前提下提高设备检修效率,减小检修维护成本。     

一种小功率电子镇流器起动电路的设计

设计了一种小功率电子镇流器起动电路,该起动电路在起动时,能为灯提供足够的起动电压将灯点亮。在稳态时可以使灯工作于低频叠加高频的方波电压,从而避免了声谐振的发生。     

基于LCC-VSC多端混合直流输电系统的启停控制策略及动模试验

为了研究验证基于电网换相换流器-电压源换流器(line commutated converter-voltage source converter,LCCVSC)多端混合直流输电系统的启停控制策略,搭建了完整双极的LCC-VSC三端混合直流输电动模平台,在LCC(整流)-VSC(逆变)、VSC(整流)-LCC(逆变)以及VSC(整流或逆变)接入常规LCC直流输电系统等混合直流输电运行模式下,对系统的启动和停止等关键控制策略以及一端投退对多端混合直流输电网络的影响进行了实验研究,并根据实验结果对混合直流系统的主要控制功能和特点进行了分析。实验结果表明所提出的控制策略能够实现混合直流输电系统的平稳启停和在线投退。     

电网换相换流器和电压源换流器串联组成的混合直流换流器控制和保护研究

基于电网换相换流器和电压源换流器串联的混合直流换流器在克服交流故障时的换相失败和直流故障时的重启动具有优势。分析了该混合直流换流器运行方式、控制策略、电压源换流器保护原理、抵御换相失败原理和直流线路重启过程,认为由该混合直流换流器组成的高压直流输电系统,可克服传统直流和柔性直流输电的主要缺点。当逆变侧的交流系统发生故障时,电压源换流器可提供电压支撑来抑制直流电流增加,缓解电网换相换流器换相失败效应。当直流线路发生故障时,逆变侧电网换相换流器可阻断电压源换流器产生的故障电流,具备直流线路故障重启能力。另外,电压源换流器还为电网换相换流器提供无功功率,从而减少换流站无功设备配置。     

考虑光伏消纳能力的配电网规划方案优化

分布式光伏接入背景下配电网发展规划是当前研究的重点。文中首先采用基于粒子群优化方法对配电网最大分布式光伏消纳能力进行评估,并与现有分析方法的性能进行了比较。采用基于全寿命周期管理的方法对配电网发展规划方案进行经济性评估,给出了规划方案全寿命周期成本分解模型,以提高单位光伏发电消纳能力的投资为指标对发展规划方案进行优化。通过具体算例说明了所提出方法的应用。为高渗透率分布式光伏接入的配电网运行和规划提供了参考。     

Life cycle assessment (LCA) and life cycle cost (LCC) analysis model for a stand-alone hybrid renewable energy system

Nowadays the biggest challenge for most organizations is a real and substantial application of sustainability through the measurement and comparability of results in order to satisfy the principles of sustainability of all the stakeholders. Definitively, it is necessary to pursue sustainability through the measurements of specific indicators and control the variables that influence the state of the economic, social and environmental issues. The aim of this paper is to contribute to the development of a comprehensive, yet practical and reliable tool for a systematic sustainability assessment, based on the Life Cycle Assessment (LCA) and the Analytic Hierarchy Process (AHP) to support decision makers in complex decision problems in the field of environmental sustainability. The results are applied to a novel compressed air energy storage system proposed as a suitable technology for the energy storage in a small scale stand-alone renewable energy power plant (photovoltaic power plant) that is designed to satisfy the energy demand of a radio base station for mobile telecommunications. The outcome is a dynamic analysis and iterative integrated sustainability assessment of corporate performance.