Dynamic simulation-based fault evaluation and recovery for heat-electrical integrated energy system

Owing to strong coupling and complicated structure, faults within heat-electrical integrated energy system (HE-IES) can trigger cascade propagation effects, severely impacting system stability. To maintain fault impacts within an acceptable range, this paper proposes a comprehensive fault evaluation framework and a two-stage fault recovery strategy for HE-IES. First, detailed dynamic models and simulation methods for fault-state HE-IES are introduced. Then, a dual-layer, eleven-indicator fault evaluation framework is developed to assess fault severity based on the affected component’s location and the extent of system state deviations. Furthermore, to meet the high demands for rapid fault recovery, a topology mapping method is proposed to simplify multi-source heating networks into single-source networks, reducing computational burden in simulation. Based on this, an offline-online two-stage fault recovery strategy is designed: the offline stage generates a source output coefficient matrix, enabling efficient source output adjustments during the online stage. Finally, a case study shows that pipe burst occurring closest to the heat source is the most severe fault due to its location and the power system’s robustness. The proposed recovery strategy reduces the average variation in heating temperature to just 1.765 % and lowers the risk index by 71 %, significantly enhancing thermal system stability while concurrently containing cascade propagation to the electrical grid, demonstrating its effectiveness in mitigating fault impacts and enhancing system resilience.