适用于压缩机定速控制的电-气综合能流计算方法

Calculation Method of Integrated Electricity-Gas Energy Flow for Compressors with Constant Speed Control

现有天然气网水力计算和电-气综合能流计算研究无法适用于气网中广泛采用的定速控制压缩机,适用于压缩机其他控制模式的能流计算方法也缺乏系统的讨论。为此,基于离心式压缩机的工作特性和定速控制模式,采用水力计算的节点法和回路法,提出适用于压缩机定速控制模式的扩展节点法、解节点-支路法和扩展节点-回路法,并将其推广应用于电-气综合能流计算。分别用3个不同结构和规模的气网算例和IEEE 39节点电网+比利时20节点气网、IEEE 118节点电网+48节点气网这2个电-气综合能源系统算例验证了所提方法的有效性,并对比分析了3种方法的计算性能。算例结果表明,扩展节点-回路法在初值依赖性和工况适应性方面的优势明显,而现有研究中广泛采用的节点法则具有初值依赖性强、工况适应性差的问题。

The existing research on the hydraulic calculation of the natural gas network and the integrated electricity-gas energy flow calculation is not suitable for the compressors with constant speed control which are widely used in the gas network.The energy flow calculation method suitable for other compressor control modes is also lacking systematic discussion.In this regard,based on the operation characteristics and constant speed control mode of centrifugal compressors,the extended nodal method,node-branch method,and extended node-loop method are proposed for the constant speed control mode of compressors by using the nodal method and the loop method of the hydraulic calculation,and also extended to the integrated electricity-gas energy flow calculation.Three cases of gas network with different topologies and scales,and two cases of integrated electricity-gas energy systems,i.e.,the coupled IEEE 39-bus system and the Belgian 20-bus gas network,and the coupled IEEE 118-bus system and the 48-bus gas network,are used to verify the effectiveness of the proposed methods.And the computational performances of the three methods are compared and analyzed.Simulation results show that the extended node-loop method has obvious advantages in terms of initial value independence and operation condition adaptability,while the nodal method widely used in the existing research has the problems of strong initial value dependence and poor operation condition adaptability.