Operational Risk Analysis Of Active Distribution Network Considering Coupling Of Cyber-Physical System

With the development of smart grids,information and communication technologies and advanced measurement devices have been widely used in power systems,achieving a high degree of automation and intelligence,and greatly improving the system’s operating efficiency.However,as the relationship between the information space and the physical space becomes closer and closer,the operating mode of the power system has also changed and some new features have emerged,forming a cyber-physical system(CPS),whose core technical feature is the usage of information technology to enhance the perception and control of physical system.The integration of information flow and energy flow allows risks to be transmitted to each other in CPS.Therefore,studying the operation risk of power grid with the coupling of the cyber-physical system is helpful to understand the true risk of the system.It is of great significance for the management of the smart grid in the future.Active distribution network,as a typical product of smart grid construction,realizes the access of renewable energy resource and demand response.In order to maximize the use of renewable energy and improve the reliability of power supply,the operation control and energy management of active distribution network require the support of a large number of intelligent electronic equipments and information and communication technologies.Therefore,in the analysis of the operational risk of the active distribution network,in addition to the failure of components in the physical space,the impact of the information space should also be considered.The following research has been carried out in this paper:(1)Firstly,the structure of active distribution network considering the coupling of the cyber-physical system is established,and its cyber-physical interaction mechanism is studied.Secondly,risk in the cyber space is analyzed and modeled,which mainly includes the network attack and the topology connectivity of the information link,the reliability of delay and data errors.Finally,Monte Carlo simulation method is used to evaluate the operation risk of distribution network.(2)The impact of distributed photovoltaics considering the coupling of cyber-physical systems on the operation risk of distribution networks is studied.First,a micro-inverter-based photovoltaic CPS structure is established.Second,The eight-state transition model of photovoltaic system is established using Markov process.Then using Poisson random number methods to simulate information attacks,and different CPS repair time strategies are proposed.Finally,a case study is carried out by Monte Carlo method.(3)Demand response,as an effective regulation method on the demand side,plays an important role in improving the reliability of the distribution network.Based on the demand response structure of the load aggregator,this paper analyzes the cyber-physical coupling characteristics in demand response’s implementation.Secondly,the effects of failure of information equipment and cyber load rate on reliability of demand response are studied.A operation model of demand response based on maximizing LA’s economic benefits is established,combining the analysis of economy and reliability.Finally,a case study is performed.