考虑薄弱成因的电网脆弱线路分类与类别辨识

针对不同运行状态下系统对脆弱性评估侧重点的差异性,提出了一种考虑薄弱成因的电网脆弱线路类别辨识方法。将脆弱线路分类为易故障线路和易受影响线路,用于辨识连锁故障的源头和传播环节,以便运行人员对脆弱线路进行更全面精确的监控。类别辨识方法基于复杂网络理论和泰尔指数实现。引入线路攻击难度和攻击成效对边韧性度进行改进,进而提出结构相对脆弱度指标。基于泰尔指数定义冲击泰尔熵和抗冲击泰尔熵,结合剩余消纳能力提出状态评估指标。建立考虑结构相对脆弱度和状态评估指标的脆弱线路综合评估模型,从电网拓扑结构和运行状态两个角度实现对脆弱线路的类别辨识。以IEEE 39节点系统和IEEE 118节点系统为算例进行测试,结果验证了所提方法的有效性。

Category Identification of Power Grid Vulnerable Lines Based on the Vulnerable Causes

A category differentiation method of power grid vulnerable lines is proposed by analyzing the causes of the line vulnerability, considering the emphases of line vulnerability assessment in various system states. The easy-breakdown line and easy-affected line are differentiated to distinguish the source with the intermediate link during cascading failure, and the method is realized by complex network and Theil theory. Firstly, structural relative vulnerability is proposed by tenacity index utilizing line load ratio and power supply capacity to make a distinction between attack difficulty and attack effectiveness. Then, state evaluation model is proposed by the impact Theil entropy and anti-impact Theil entropy considering residue consumptive ability of transmission lines. Finally, comprehensive evaluation model of vulnerable lines is established to realize category identification overall combining the structural relative vulnerability and state evaluation model. Case studies were carried out respectively on the IEEE 39-bus and the IEEE 118-bus test system to demonstrate the validity of the proposed method.