Situation Awareness Of Active Distribution Network Considering Cyber-attack

Situational awareness originated from the research onhuman factors of the American space shuttle in the 1980 s.It was first proposed and defined as the detection,understanding and prediction of elements or objects in the specified time and space by Mica R.Endlsey of Texas Technological University.Because of its high practical value,it has been widely used in transportation,military,medical and other fields.As a multi-dimensional complex system of comprehensive computing,network and physical environment,cyber-physical system provides a new idea for the development of smart grid.Grid Cyber-Physical System is regarded as the basic structure of the next generation power system.Grid CPS is an intelligent and autonomous system,which realizes a high degree of coupling between cyber system and power system.The two systems interact and depend on each other.Information system brings flexible and diverse control means for power grid,but it can also bring information security risk for Grid CPS.In power system,situational awareness is to understand,evaluate and predict the operation trajectory of power grid by collecting online data and offline information in the system and to present it visually.At present,there are some research results on the understanding level of power grid situational awareness,but the research on situation prediction is still in the initial stage,lacking of prediction methods that meet the characteristics of power grid operation,and the core technologies still need to be broken through.Based on the above background,this paper studies the cooperative awareness and defense method of CPS situation in distribution network considering cyber attacks.The specific research contents include the following aspects:1)The structure of active distribution network is briefly analyzed,and the types of network attacks that power grid may suffer are expounded,and provides reference for the follow-up research work.2)The concept of grid CPS situational awareness is defined and the framework of power network CPS situational awarenessis constructed.The key issues and key technologies to be solved in power network CPS situational awarenessand the possible application scenarios of power network CPS is summarized.A possible attack scenario based on Ukraine power grid blackoutsis conceived,and the idea of cooperative situational awareness and defenseis given.3)Aiming at the third kind of cyber attack summarized above,the index system of situation assessment of active distribution network is constructed,which includes the index of safe operation of active distribution network,the index of stability of distributed generation and the index of risk of active distribution network considering cyber attack.Based on the grey relational analysis method,the situation assessment model of active distribution network is established,and the weight of each index is objectively revised by the entropy weight method.The evaluation results of different scenarios are compared,and the evaluation results are analyzed theoretically,and the evaluation model proposed in this paper is validated.4)In order to meet the real-time requirement of situation prediction in situational awareness,multiple sliding time windows are introduced into the grey prediction model to improve the prediction accuracy.Because of the existence of distributed generation,similar day samples are defined,and the change regulation of similar day situation is extracted by wavelet neural network.Based on this,the prediction results are corrected,which reduces the influence of fluctuation of distributed generation with weather on the prediction results.The example proves the prediction accuracy of the model and the validity of the correction method.The idea of cooperative prediction of CPS situation in active distribution network considering cyber attack is given.5)The active defense system of power grid based on P2DR2 security model is constructed.The model is improved from the powergrid side and cyber side,and the link of early warning and cyberattackstraceability is added.The cooperative active defense strategy of grid CPS cyber side and powergrid side for cyber attack is proposed.The research work carried out in this paper can provide a basis for the research of the stability control method of distribution network,so as to escort the further development of smart grid.In addition,the research framework of CPS situation cooperative awareness,active distribution network situation prediction model and active defense system based on P2DR2 security model proposed in this paper can provide a basis for future research.