电-气综合能源系统的综合灵敏度指标构建方法和应用研究

Research on Construction Method and Application of Composite Sensitivity Index for Integrated Electricity and Natural Gas Systems

燃气轮机和电转气(power-to-gas,P2G)技术的日益成熟逐渐加深电力系统和天然气系统的耦合程度。在电-气综合能源系统的联合运行中,子系统的扰动会通过耦合元件跨系统传播,从而影响整个系统的安全运行。为研究电-气综合能源系统中子系统间的相互影响,基于牛顿拉夫逊法建立了统一潮流模型并实现了联合求解,其中天然气系统的状态变量采用牛顿下山法更新,一定程度上避免了初值敏感性。随后,基于统一潮流模型构建了节点电压/节点气压-注入节点功率综合灵敏度指标,同时获取了规范化的电压/气压灵敏度矩阵,可以定量评估系统多种扰动的共同影响并分析耦合系统的相互作用机理。算例分析验证了潮流算法和所提指标的有效性,并讨论了燃气轮机和P2G装置耦合作用下子系统间的影响关系。

The development of gas turbine(GT)and powerto-gas(P2G)technologies deepens the coupling of electric power systems(EPS)and natural gas systems(NGS).In the combined operation of integrated electricity and natural gas systems(IEGS),the disturbance of a subsystem spreads across other subsystems through coupling components,thus affecting the secure operation of the whole system.In order to study the interactions of subsystems in IEGS,a unified power flow model is established and solved by the Newton Raphson algorithm,where the state variables of NGS are updated using the Newton Down-hill algorithm to avoid the sensitivity of initial condition.Then,the composite sensitivity indices of nodal voltages/pressures to nodal power injections are defined,and the normalized sensitivity matrices related to nodal voltages and pressures are obtained,which can provide theoretical support for quantitative evaluation of multiple disturbances and analysis of interaction mechanisms in IEGS.Case studies verify the effectiveness of the developed power flow method and the defined sensitivity indices.In addition,the interaction relationships of subsystems in IEGS under the coupling of GT and P2G are investigated.