You must read papers (YMRPs)

Backward and forward sweep

[1] C. S. Cheng and D. Shirmohammadi, "A three-phase power flow method for real-time distribution system analysis," IEEE Trans. Power Systems, vol. 10, pp. 671-679, 1995.

IEEE test feeders

Please read the following [1] or [2].

[1] W. H. Kersting, "Radial distribution test feeders," IEEE Transactions on Power Systems, vol. 6, no. 3, pp. 975-985, 1991.

[2] W. H. Kersting, "Radial distribution test feeders," in 2001 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.01CH37194), 28 Jan.-1 Feb. 2001 2001, vol. 2, pp. 908-912 vol.2, doi: 10.1109/PESW.2001.916993.