基于安全性分析电力系统地震功能失效研究

电力系统地震功能失效有两种方式,一是物理功能失效,二是供电流功能失效。对系统供电流功能失效进行了深入的研究。首先用模糊矩阵对受地震干扰的系统进行连通性分析,之后运用灵敏度安全法对系统进行安全性分析。该方法是将因地震引起的电力供应系统线路开断视为系统正常运行的一种扰动,从系统供电流方程的Taylor级数展开式出发,得到灵敏度矩阵,以系统节点注入的功率增量来计算系统运行变量增量,为判断系统运行状态提供依据。最后结合一个实例验证了该方法的实用性,该工作可作为电力系统地震功能失效分析的理论基础,为电力系统地震防灾和工程加固提供理论依据。     

生命线网络系统增设冗余单元的抗震加固优化策略

探讨了以增设冗余单元来提高在役生命线网络系统的抗震可靠性,通过对可增设单元进行重要度分析,并考虑地震环境下的失效相关性,讨论了冗余单元增设的概念性原则,通过建立增设单元的优化决策数学模型,并利用生命线弧单元设计方案的离散性,建立了增设加固优化设计的实用方法。     

交通系统地震服务性能分析

本文论述了交通系统的震害,建立了城市交通系统地震救灾服务功能模型及评估方法以及救灾功能的可靠性分析方法,提出了基于可靠度的系统地震服务功能的分析方法和最佳路径优化方法,并以可靠度和道路长度作为协调参数,运用优化方法解决了交通系统安全性和经济性之间的矛盾,提出了交通系统加固优化的实用的分析方法。最后以某城市交通网络系统为例进行了分析研究,为城市交通系统防震减灾研究提供理论基础。     

网络可靠度分析的最小割递推分解算法

基于不交最小割求解系统失效概率的思想,提出了求解网络系统失效概率的最小割递推分解算法。在此基础上,利用概率不等式给出了失效概率的上、下界,从而可以通过控制上、下界之间的误差来获得计算精度和计算时间之间的平衡。计算实例分析表明,该算法能计算给出中、小型网络失效概率的精确值,并能够高效、高精度地求解出大型复杂网络系统的失效概率。     

生命线网络抗震可靠度的一般算法

针对生命线工程中所特有的顶点失效问题和失效相关性问题，本文提出了其网络可靠性分析的一般计算方法。     

高压变电站1(1/2)主接线系统抗震可靠性分析

讨论了高压变电站１１／２电气主接线系统的抗震可靠性方法,针对这种接线形式的特点,提出应当按网络系统计算系统的可靠性,并提出了３种可靠性分析准则,以计算系统的可靠性。实例分析表明,具有１１／２电气主接线系统的变电站,虽然各个电气设备的抗震可靠性不是很高,但其主接线系统的抗震可靠性可以比单个设备可靠性高得多。     

大型城市管网抗震可靠性分析与优化

本文提出了地震作用下供水系统的渗漏模型,发展了地震后带渗漏管网的流分析技术,结合一次二阶矩方法获得了地震后供水管网的功能可靠度。针对供燃气管网系统则提出了一类高效精确的大型网络抗震连通可靠度分析的概率解析算法———递推分解算法。以上述管网抗震可靠性分析理论为基础,分别发展了基于模拟退火算法的供水系统网络拓扑优化分析理论和基于遗传算法的供燃气网络系统拓扑优化理论。     

泰安市交通系统抗震可靠性分析

本文根据网络可靠性理论,针对泰安市交通系统网络模型进行抗震分析研究;采用Monte Carlo随机模拟技术,以及道路、桥梁单元可靠性分析方法,给出了不同烈度下网络中各节点的可靠度。分析了网络系统存在的薄弱环节,为泰安市防灾规划提供理论依据。     

交通网络震后整体功能失效评估方法

以交通网络通行能力为系统功能状态评价参数,基于单元的基本属性及网络拓扑结构引进单元重要度系数,结合单元地震破坏状态及其功能失效状态的对应关系,通过加权求和得到交通网络震后的总体通行能力,并将其与震前总体容量的比值作为系统功能失效状态判断指标。最后,以某城市道路网络为例,对所提出方法的可行性进行验证。结果表明：以震害评估...     

震区道路系统规划设计方案的量化分析

提出以最小路集,合理路集以及堵塞、失效相关程度等进行震区新建道路网络系统规划设计方案的量化评估方法,通过算例说明该方法不仅可行且便于应用。     

基于模拟退火算法的供水管网抗震优化设计

本文以管网造价为优化目标,管网拓扑结构为优化参数,管网节点最低可靠度为约束条件,建立了供水管网抗震拓扑优化模型。在供水管网功能可靠性分析方法的基础上,结合单元概率重要度分析方法,利用模拟退火算法提出了供水管网的抗震拓扑优化方法,并对一典型供水管网进行了拓扑优化分析。分析表明,对于管网抗震拓扑优化这样一个组合优化问题,模拟退火算法提供了一类很好的途径,以此为基础进行供水管网抗震可靠性优化设计具有很好的效果。     

A recursive decomposition algorithm for network seismic reliability evaluation

A new probabilistic analytical approach to evaluate seismic system reliability of large lifeline systems is presented in this paper. The algorithm takes the shortest path from the source to the terminal of a node weight or edge weight network as decomposition policy, using the Boolean laws of set operation and probabilistic operation principal, a recursive decomposition process then could be constructed. For a general weight network, the modified Torrieri method (NTR/T method) is introduced to combine with the suggested algorithm. Therefore, the recursive decomposition algorithm may be applied to evaluate the seismic reliability of general lifeline systems. A series of case studies, including a practical district electric power network system and a large urban water supply system, show that the suggested algorithm supplies a useful probabilistic analysis means for the seismic reliability evaluation of large lifeline systems. Copyright © 2002 John Wiley & Sons, Ltd.     

Multi‐scale system reliability analysis of lifeline networks under earthquake hazards

Recent earthquake events evidenced that damage of structural components in a lifeline network may cause prolonged disruption of lifeline services, which eventually results in significant socio‐economic losses in the affected area. Despite recent advances in network reliability analysis, the complexity of the problem and various uncertainties still make it a challenging task to evaluate the post‐hazard performance and connectivity of lifeline networks efficiently and accurately. In order to overcome such challenges and take advantage of merits of multi‐scale analysis, this paper develops a multi‐scale system reliability analysis method by integrating a network decomposition approach with the matrix‐based system reliability (MSR) method. In addition to facilitating system reliability analysis of large‐size networks, the multi‐scale approach enables optimizing the level of computational effort on subsystems; identifying the relative importance of components and subsystems at multiple scales; and providing a collaborative risk management framework. The MSR method is uniformly applied for system reliability analyses at both the lower‐scale (for link failure) and the higher‐scale (for system connectivity) to obtain the probability of general system events, various conditional probabilities, component importance measures, statistical correlation between subsystem failures and parameter sensitivities. The proposed multi‐scale analysis method is demonstrated by its application to a gas distribution network in Shelby County of Tennessee. A parametric study is performed to determine the number of segments during the lower‐scale MSR analysis of each pipeline based on the strength of the spatial correlation of seismic intensity. It is shown that the spatial correlation should be considered at both scales for accurate reliability evaluation. The proposed multi‐scale analysis approach provides an effective framework of risk assessment and decision support for lifeline networks under earthquake hazards. Copyright © 2009 John Wiley & Sons, Ltd.     

生命线工程网络抗震可靠性算法研究

现代城市的迅速发展对生命线工程系统依赖性逐渐增强。地震后生命线工程系统的性能直接决定了灾后生活和生产的恢复以及抢险工作的进行,因此对生命线工程系统进行地震作用下的可靠性分析具有十分重要的意义。本文中主要介绍2种求解大型网络抗震可靠度算法———最小路递推分解算法和最小割递推分解算法。在此基础上,利用这2种算法对沈阳市供气系统进行了分析。研究结果表明,合理选择使用这2种算法可以有效的进行不同地震烈度条件下的大型生命线工程系统的可靠性分析。     

Genetic algorithm for seismic topology optimization of lifeline network systems

Lifeline systems, such as water distribution and gas supply networks, usually cover large areas. For these systems, seismic design is always a difficult problem because of the complexity of large‐scale networks. In this paper, a topology optimization technology for lifeline networks is established. Firstly, in order to speed up the convergence of optimization process, an element investment importance analysis is carried out to evaluate the importance of components to the lifeline network. Then a topology optimization model is established. The aim of the model is to find the least‐cost network topology while the seismic reliability between the sources and each terminal satisfies prescribed reliability constraints. For this optimization problem, a genetic algorithm, which takes network topologies as the individuals of its population, is used to search for the optimal solutions by suitable operators, including selection, crossover and mutation operators. The capacity of the proposed algorithm is illustrated by its applications to a simple example network consisting of 10 nodes and an actual network with 391 nodes located in a large city of China. Copyright © 2008 John Wiley & Sons, Ltd.     

Decomposition algorithms for system reliability estimation with applications to interdependent lifeline networks

Reliability and risk assessment of lifeline systems call for efficient methods that integrate hazard and interdependencies. Such methods are computationally challenged when the probabilistic response of systems is tied to multiple events, as performance quantification requires a large catalog of ground motions. Available methods to address this issue use catalog reductions and importance sampling. However, besides comparisons against baseline Monte Carlo trials in select cases, there is no guarantee that such methods will perform or scale well in practice. This paper proposes a new efficient method for reliability assessment of interdependent lifeline systems, termed RAILS, that considers systemic performance and is particularly effective when dealing with large catalogs of events. RAILS uses the state‐space partition method to estimate systemic reliability with theoretical bounds and, for the first time, supports cyclic interdependencies among lifeline systems. Recycling computations across an entire seismic catalog with RAILS considerably reduces the number of system performance evaluations in seismic performance studies. Also, when performance estimate bounds are not tight, we adopt an importance and stratified sampling method that in our computational experiments is various orders of magnitude more efficient than crude Monte Carlo. We assess the efficiency of RAILS using synthetic networks and illustrate its application to quantify the seismic risk of realistic yet streamlined systems hypothetically located in the San Francisco Bay Region.     

Reliability upgrading of lifeline networks for post-earthquake serviceability

Efficient procedures for reliability upgrading of existing lifeline networks for post-earthquake serviceability are presented. A simple method is developed to determine critical components of the network whose strengthening improves the network reliability for specified serviceability criteria. Measures of effectiveness of strengthening each component are also introduced. Based on critical components and measures of effectiveness, step-by-step upgrading procedures are proposed. Both connectivity and minimum-flow serviceability criteria may be specified. Two upgrading objectives considered are achieving a specified target reliability and reducing the total costs of upgrading plus expected losses due to failure of the lifeline. A hypothetical application to a water-distribution system in the San Francisco Bay Area illustrates the proposed method.     

基于脆性理论的灾害作用下生命线系统耦联分析

一个城市或地区的承灾能力主要看其基础设施的承灾能力,其中最重要的一个部分就是生命线系统的承灾能力。在分析评价生命线系统承灾能力时,不仅要考察复杂性、均衡性和可靠性这些网络特征,还要考虑各子系统间的关联性。这种关联对生命线系统整体的承灾能力有削弱作用。根据复杂系统脆性理论的思想和脆性联系熵的方法,提出了用系统综合脆性联系熵来反映和评价生命线系统整体的关联特性,并通过判断各子系统间的相互影响关系,量化了生命线系统整体的易损性。经耦联关系分析和计算,灾害破坏下,从生命线系统相互作用来看,电力系统受其他子系统的影响最大;而由于供水系统的关键性和其影响方式的不确定性,灾后首先要恢复的是供水系统的工作或供给。证明了该方法为优化系统组织管理、控制灾后的修复工作和协调子系统间的关系提供了依据。     

基于DEA分析的生命线网络节点抗灾相对可靠度评估

对于生命线工程网络系统而言,合理分析和评估其带有网络特征的节点可靠度,比只研究单体可靠度更具实际意义。基于数据包络分析法（Data Envelopment Analysis,DEA）有效性分析的思想,提出了生命线网络节点抗灾相对可靠度的概念。从生命线工程在灾害环境下着重体现出的系统性和网络性出发,考察网络中的节点所能实现的资源供给功能与其所在网络中的空间结构重要性是否匹配,即功能性相对于结构性的可靠度。选择节点资源实际需求量和管内水压作为DEA有效性分析的输入参数,结构重要性作为输出参数,并用网络中介中心性评价结构重要性,获得相应参数。通过实例分析,得出实例工程网络中各节点相应的DEA有效性分析结果,即相对可靠度,并通过对参数的权系数调整,得到了使非有效单元变为有效单元的调整值。该调整值可供优化及改进工程网络的技术性调整方案参考,相对可靠度也可作为评价工程网络系统性能的有益补充。     

生命线工程系统中运行设施元件可靠性的分析研究

本文研究了生命线工程系统中运行设施的元件破坏状态和可靠性分析方法，给出元件的破坏状态分级标准、判断准则和元件可靠度的计算方法，这对建立一个实用的生命线工程抗震能力分析的专家系统是十分有意义的。