Abstract: Power grid topology identification for large power grid trajectories is of great significance for informationdriven large power grid operation situation awareness and intelligent control. Firstly, based on the principle of power balance and power flow constraints, the identification of power grid topology was reduced to the problem of seeking the global optimal combination of box and ball. The idea of power grid topology identification was given from a new perspective, which simplified the complex process of traditional power grid topology identification. Secondly,according to the power flow balance characteristics of bus nodes, a mathematical model of power grid topology identification was established, which improved the efficiency of power grid topology identification from the perspective of global optimization. At the same time, the voltage loss was introduced to overcome the non-uniqueness problem of power grid topology identification. Thirdly, the immune intelligent algorithm was used to solve the model. The algorithm effectively maintained the diversity of antibodies and avoided the premature convergence problem. Finally, the proposed method was tested on IEEE 39 and IEEE118 bus systems to verify the effectiveness.