Abstract: With the popularity of electric vehicles, large-scale electrical traffic load is an increasing burden for power system, the uncontrolled charging behavior also increases the risk of power grid cascading failure propagation and road congestion, power grids and traffic network needed a "wisdom mind" - information network to command these behaviors, Therefore, the power grid, information network and traffic network have become a new development trend. However, the coupling of networks will not only increase the robustness of the network, but also increase the vulnerability of the network. This paper studies the coupling mechanism among the three networks. On this basis, the reliability of the three networks is verified by comparing with the traditional power grid and traffic network model.