输气系统管网延时稳态建模与特性研究

Steady State Modeling and Characteristics Study of Delay in Gas Transmission System

在跨区域综合能源系统中,能源远距离传输使得流体系统的时间延迟现象更加显著,常规的多能流稳态模型亟待改进。考虑到目前输电系统稳态模型已相对完善,而输气系统流体特性研究尚不充足,因此,该文针对输气系统的延时特性进行分析,旨在为考虑输气系统延时特性的电–气综合能源系统,提供一种关于流体系统精准建模与求解分析的可行思路。该文首先研究了考虑管网延时特性的天然气系统建模理论,通过构造具有即插即用特性的虚拟元件"延时能量偏差器",量化延时对管网管存等参数的影响程度;然后提出计及管网延时特性的天然气能量流稳态求解算法;最后设置具体算例,探究天然气网络状态对管网受延时影响程度的影响,与调度间隔对延时效应被计及与否的影响。经算例验证,在日内调度情景下,所提模型可有效反映管网延时效应对管网压力、流量和管存能量的影响程度。

In a cross-region integrated energy system,the long-distance transmission of energy may result in a more significant time delay characteristic of fluid system.The conventional multi-energy steady state flow model needs further improvement.Since the current steady state model of the transmission system has been relatively perfect,the fluid characteristics of gas transmission system are not sufficient.Therefore,this paper analyzed the delay characteristics of natural gas transmission system.It aims to provide a feasible method for accurate modeling and solution analysis of fluid systems for electricity-gas integrated energy system considering time delay characteristics of gas transmission system.This paper studied the natural gas system modeling theory considering time delay characteristics of pipe network.By constructing the virtual component named as"delay energy deviation"with plug and play characteristics,the influence of time delay on line-pack and other parameters was quantified.Moreover,a steady-state solution algorithm for gas energy flow considering time delay characteristics of pipelines was proposed.Finally,a specific example was set to explore the influence of gas network status on extent of network affected by delay,and the influence of scheduling interval on whether delay effect being taken into account.It is verified by the example that the model proposed can effectively reflect the influence of delay effect on node pressure,pipeline flow and line-pack in intra-day scheduling scenario.