The highly intricate inter-connectivity and ever expanding scale of modern power grids have raised serious concerns on security and vulnerability of power grids. Much of the recent study on the vulnerability of power grids to cascading failure has focused on the structural changes or functional damage of the system, and results from previous studies often draw inconsistent and even contradictory conclusions. In this paper, the causes of these diverse and inconsistent results relating to structural and functional damages have been identified. In addition, the system’s vulnerability to cascading failure is studied from an attacker’s perspective, and a node attack strategy maximizing structural and functional damage is considered. Specifically, the problem of finding the optimal node attack strategy is formulated as a multi-objective optimization problem, and evolutionary algorithms are used to generate optimal solutions. Simulation results on four benchmark test systems show significant advantages of the proposed algorithms over heuristic and single-objective methods, and give important insights on identifying the critical nodes affecting vulnerability of power grids.

中文翻译：

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揭示电网的结构和功能脆弱性，以防止级联故障

现代电网的高度复杂的互连性和不断扩大的规模引起了人们对电网安全性和脆弱性的严重关注。最近有关电网易遭受连锁故障的脆弱性的许多研究都集中在系统的结构变化或功能损坏上，而先前研究的结果常常得出不一致甚至矛盾的结论。在本文中，已经确定了导致这些与结构和功能损坏有关的各种不一致结果的原因。此外，还从攻击者的角度研究了系统级联故障的脆弱性，并考虑了使结构和功能破坏最大化的节点攻击策略。具体来说，寻找最优节点攻击策略的问题被表述为多目标优化问题，并使用进化算法来生成最优解。在四个基准测试系统上的仿真结果表明，与启发式和单目标方法相比，该算法具有明显的优势，并且在识别影响电网脆弱性的关键节点方面提供了重要的见识。