Most of the traditional structural heterogeneity analysis of the power grid only considers the structure of the power grid itself but lacks the structural heterogeneity analysis of the power grid with the participation of uncertain load of electric vehicles. In view of this, this paper introduces the Gini coefficient and puts forward an analysis method of power grid structure heterogeneity which comprehensively considers network weighted topological entropy and electrical betweenness. Firstly, based on CFSFDP (clustering by fast search and finding of density peaks), the charging load of electric vehicles is cluster analyzed to obtain the charging load characteristics in different scenarios and at different times of the day; Secondly, the Gini coefficient is used to analyze the node betweenness and line betweenness of the network, and the uniformity coefficient of the network structure is constructed, and the betweenness is combined with the network topological entropy to build a comprehensive evaluation index of the heterogeneity of the network structure; Finally, taking IEEE39-bus system as an example, the simulation analysis shows that this method can effectively and quickly evaluate the network structure balance with external random load.