基于简化拓扑结构的陕京天然气管网供气可靠性分析

为了定量分析结合了拓扑结构与水力计算的天然气管网的供气可靠性,以陕京天然气管网为分析对象,提出了一种通用的天然气长输管网系统供气可靠性评估方法。首先从上述天然气管网的拓扑结构入手,将站场与天然气管段视为网络结构的结点与链路单元,对系统进行了简化,建立了天然气管网系统的拓扑结构模型;然后通过设备失效数据库确定了系统各单元的事故率分布,耦合基于故障率分布的蒙特卡洛模拟生成了天然气管网的拓扑结构;最后再结合水力计算得到一定拓扑结构下陕京天然气管网的供气能力。结果表明:①无论是用气高月还是用气低月,该管网都保持了很高的供气可靠性;②陕京一、二、三线3条天然气管道构成了具有一定拓扑结构的供气网络,增加了系统的鲁棒性,从拓扑结构层面也提高了供气的可靠性。结论认为,该项研究成果给出了天然气管网供气可靠性的定量计算方法,为天然气管网供气可靠性分析提供了技术支持。

Gas supply reliability analysis of the Shaanxi–Beijing gas pipeline network based on the simplified topological structure

For a quantitative analysis of gas supply reliability of natural gas pipeline networks based on the topological structure and hydraulic calculation, a universal method to evaluate gas supply reliability of a long-distance gas pipeline network system was developedwith the Shaanxi–Beijing Gas Pipeline network as an example. First, the system was simplified by taking stations and gas pipeline sections as the nodes and link units of network structures based on the topological structures of gas pipeline networks, and then its topologicalstructure model was built up. Second, the accident rate distribution of each unit in the system was determined by virtue of the equipment failure database, and the topological structure of gas pipeline networks was established by fitting the Monte-Carlo simulation based on failure rate distribution. Finally, by hydraulic calculation, the gas supply capacity of Shaanxi–Beijing Gas Pipeline network in a certain topological structure was worked out. It is indicated that the Shaanxi–Beijing Gas Pipeline network is quite high in gas supply reliability both in high gas-consumption months and low gas-consumption months. Besides, the first, second and third Shaanxi–Beijing gas pipelines constitute the gas supply network with a certain topological structure, increasing the robustness of the system. As a result, its gas supply reliability is improved as far as topological structure is concerned. It is concluded that this research provides a quantitative calculation method for the gas supply reliability of gas pipeline networks and as well as a technical support for guaranteeing the gas supplyof gas pipeline networks.