For the load modeling of a large power grid

the large number of substations covered by it must be segregated into several categories and

thereafter

a load model built for each type. To address the problem of skewed clustering tree in the classical hierarchical clustering method used for categorizing substations

a fair hierarchical clustering method is proposed in this paper. First

the fairness index is defined based on the Gini coefficient. Thereafter

a hierarchical clustering method is proposed based on the fairness index. Finally

the clustering results are evaluated using the contour coefficient and the t-SNE two-dimensional plane map. The substations clustering example of a real large power grid considered in this paper illustrates that the proposed fair hierarchical clustering method can effectively address the problem of the skewed clustering tree with high accuracy.