Abstract: To solve the clustering problem caused by the layout design of railway electrical equipment, this paper proposed the BiKMeans_SC algorithm based on the KMeans algorithm, implemented automatic clustering with unknown number of clusters and size constraints, and its usability was demonstrated through simulation experiments. Based on the BiKMeans_ SC algorithm, the paper developed an auxiliary design software for railway electrical equipment layout, which implemented clustering processing of electrical equipment based on plane positions, used the A* algorithm to automatically plan the path of electrical equipment cables, realize the automatic generation of electrical equipment cable connection diagrams and cable engineering quantities. Experimental results have shown that compared to traditional manual design methods, this software has a high level of automation, reliable calculation processes, and accurate results, which is conducive to improving the design quality of railway electrical equipment layout, controlling construction investment costs, and better serving railway engineering construction.