考虑可观测性的电力信息物理系统级联故障分析方法

Cascade Failure Analysis Method for Power Information Physical System Considering Observability

传统的电力信息物理系统故障分析往往仅考虑了网络间的故障波动,而很少考虑故障波动对系统观测能力的影响。系统观测能力对电网调度方案的制定特别重要,尤其是发生级联故障时,系统可观测性的降低会给调度系统带来巨大困难,从而加剧故障损失。提出了一种计及系统可观测性的电力信息物理系统分析方法,并研究了在不同网络互相似耦合强度下的网络抗毁性。首先,搭建了一对一耦合方式电力—通信网络模型作为电力信息物理系统的物理基础,给出了系统可观测性评估指标,量化了在级联事故过程中导致电网失去全网可观性时的故障规模;其次,通过分析量化网网耦合互相似性,提出了电力信息物理系统互相似度评估指标;然后,借鉴电网级联事故模型,建立了适用于电力信息物理系统的级联事故逻辑分析流程;最后,通过IEEE 118节点仿真分析发现,发生级联故障时,电网会在级联故障结束之前失去全网可观性;耦合网络间的互相似性越高,整体网络在发生级联故障时的电网可观测性抗毁能力越强。

Traditional power cyber-physical system fault analysis often only considers the fault fluctuations between networks,but rarely considers the impact of fault fluctuations on the system observation capability.The system observation capability is particularly important for the formulation of power grid dispatching schemes,especially when cascading failures occur,the reduction of system observability will bring huge difficulties to the dispatching system,thereby exacerbating failure losses.A method for analyzing the power information physical system that takes into ac-count the observability of the system is proposed and the network invulnerability under the mutual coupling strength of different networks is studied in this paper.Firstly,a one-to-one coupling mode power communication network model is established as the physical basis of the power information physical system.The system observability evaluation index is given to quantify the faults caused the power grid to lose the full network observability during the cascade accident.Secondly,by analyzing the quantitative mutual similarity of network-network coupling,an evaluation index of mutual similarity of power information physical system is proposed.Then,based on the grid cascade accident model,the cascade logic analysis process for power information physical system is established.Finally,the IEEE118 node simulation analysis shows that when a cascade fault occurs,the grid will lose the full network observability before the end of the cascade fault;the higher the mutual similarity between the coupled networks,the grid observability of the overall network in the event of cascade failure.The stronger the resistance to destruction.