Multi-Energy Flow Calculation Method for Integrated Energy Systems Based on Modified Augmented Nodal Analysis

Integrated energy systems have emerged as a critical platform for achieving high-efficiency energy utilization and realizing dual-carbon goals by integrating heterogeneous multi-energy carriers such as electricity and natural gas. However, their strong coupling characteristics pose significant challenges to multi-energy flow calculation, including high nonlinearity and poor convergence. To address these challenges, this paper proposes a multi-energy flow calculation method based on modified augmented nodal analysis. The approach establishes a unified augmented matrix framework that embeds models of electricity and natural gas subsystems into conventional power flow computation systems. This integrated model is iteratively solved using the Newton-Raphson method. Results demonstrate that compared to the traditional NR method under a unified solving framework, MANA-NR exhibits notable advantages in the test case, including reduced iteration steps and shortened computation time. This verifies its high efficiency in handling complex coupled systems. The method not only addresses the issues of independent multi-energy subsystem models and diverse solution methods but also establishes a modeling foundation for multi-energy flow calculations.