由电力系统(electric power systems,EPS)、天然气系统(natural-gas systems,NGS)之间的耦合与互联构成的综合能源系统(integrated energy systems,IES),对于构建经济、环保、高效的能源系统至关重要。同时,由于IES中大量的不确定因素,有必要将不确定建模技术应用于IES分析。该文将广泛应用于EPS的概率潮流的概念推广到IES的概率能量流分析中,计及了EPS、NGS之间3方面的耦合:1)燃气轮机组;2)电力驱动加压站;3)能源集线器。在IES稳态能量流的基础上,考虑了电、气、热负荷以及风电场出力的不确定性,并采用蒙特卡罗模拟法求解IES概率能量流。算例分析表明,NGS(或EPS)中不确定性因素会对EPS(或NGS)的概率能量流产生影响;同时NGS能量流方程线性化精度明显低于EPS。
Integrated energy systems(IES), consisting of the coupling and interactions between electric power systems(EPS) and natural-gas systems(NGS), are expected to play an important role in constructing the economic, eco-friendly, and efficient energy systems. Meanwhile, due to the fact that IES are confronted with a wide range of uncertainties, it is essential to take advantage of uncertainty modeling techniques to analyze IES. In this paper, the concept of probabilistic load flow, which has been widely applied in EPS, was extended to IES probabilistic energy flows analysis. Three aspects of coupling between EPS and NGS are considered: 1) gas-fired generators; 2) electric-driven compressors; and 3) energy hubs. Based on the models of IES steady energy flows, the proposal is solved by Monte Carlo simulation with the consideration of uncertainties of electric, gas and heat loads and wind farms output power. Finally, test results demonstrate that the uncertainties in NGS(or EPS) do have effects on EPS(or NGS) probabilistic energy flows. Further, the accuracy of linearizing NGS energy flow equations is obvious lower than EPS.