Reliability Research On Power-ICT Dual Network Based On Coupling Model

With the development of power grid and the expansion of network scale,the application of information communication technology(ICT)network in power systems is increasingly extensive and in-depth.ICT network provides technical support for the intelligent and automated development of power grids.The two networks interact continually and deeply,and gradually integrat into a power-ICT dual?network coupling system.The local failures in the dual-network coupling system may be more serious than that of the single-network system.Therefore,the reliability research on the power-ICT dual-network system is of great significance to the stable operation of the power system.In order to reflect the directional interaction between power grid and ICT network in power system,this paper strips energy and information coupling and establishes a power-ICT dual-network system with directional coupling mode.Then considering the primary and back-up protection in protection scenario and extract the main features,and construct a recursively-controling cascade failure process of dual-network systems and reliability assessment method.Then,based on the convergence characteristic of the power ICT network services,from the perspective of suppressing the common failures of the paths from one ICT node to the dispatching node,the independent path set measure of the information side node is proposed by considering independent redundancy and the hop of the paths.Independent path set—electrical betweenness(IPS-EB)directional coupling strategy is constructed based on that.Taking the IEEE 57 system as the simulation example,the results show that for the dual-network system,increasing the number of energy coupling is more effective for improving the overall robustness of the system;by contrast with degree coupling and betweenness coupling,the dual-network system under the IPS-EB coupling strategy should be more robust against cascading failures;the directional coupled system with assortatively matching is also more robust against cascading failures and the impact of assortativity is greater than that of coupling strategies.The actual power system can consider independent path set for the ICT network and electrical betweenness for the power network to construct connections between the two networks.Based on the actual power system networking structure and service flow characteristics,this paper proposes the reliability analysis method for the power-ICT dual-network system through the improvement of the coupling model and the cascade failures model.And a coupling strategy for the dual-network system is proposed and the influence of various structural factors between the two networks on the system reliability is obtained through simulation.The method and the conclution on the reliability of the dual-network system have practical guiding significance for the improvement of the network structure and the enhancement of the reliability.