Power System Cascading Failure Analysis Considering The Effect Of Communication Network

In recent years,a lot of big blackout accidents happen,which caused by cascading failure and bringing bad influence to the national economy and social development.Traditional cascading failure analysis focuses on the operation status of power system and researches the occurrence and development mechanism of cascading failure based on complex network theory and self-organized criticality theory.The risk of communication network vulnerability to power system operation is rarely considered.Modern power system has gradually been built up to the cyber physical power system which is coupled by power network and communication network.Considering the operational status of communication network to the analysis of power system cascading failure,studying on the development mechanism of cascading failure,predicting the cascading failure path and intentionally monitoring and warning the weak link have significant importance to big blackout accidents prevention.This paper simulates the typical electric business transferring on the power dispatching data communication network.The author gathers communication network real-time data,such as channel delay,link utilization and service end to end delay,to constitute communication node and link vulnerabilities.Using OPNET simulation software to build a provincial scale power communication network simulation model.The communication network vulnerability assessment is made on conditions of communication network normal status,communication network message surging status and communication node Denial of Service-attacked status.Considering each fault branches' fault degree,health degree and the power grid nodes'communication vulnerability of corresponding communication node to construct power network fault branch outage probability model with the influence of communication nets.Using this model to predict power system cascading failure path on different communication status and presenting alann signals to high communication vulnerability and high delay branches which the basic data cannot be detected.Based on risk assessment theory,this paper uses cumulative load loss,cumulative voltage waving severity,the average communication link utilization and communication non-detection rate to construct power network cascading failure outage comprehensive consequence index.Combining with the power branch comprehensive outage probability to set up a risk evaluation model of power grid cascading failure path with the influence of communication.The author uses this model to give warning signals to high communication vulnerability branches,carefully monitors high outage probability and high risk cascading failure path.Meanwhile,this paper tries to research the influence of the DoS attacking's position and degree to the cascading failure path risk evaluation.This paper uses IEEE 39-bus system to make simulation and calculation.The results verify the effectiveness of power grid cascading failure path prediction model and risk assessment model with the influence of communication network.