Aiming at the problem of battery inconsistency in photovoltaic energy storage power station, a hierarchical active equalization system based on flyback transformer and inductance is designed. The system adopts hierarchical equalization strategy. The first layer is the internal group equalization of battery packs, and the energy transfer between adjacent batteries is realized by the inductance; the second layer is the equalization of different battery packs, which is realized by the equalization circuit based on flyback transformer. Taking the state of charge (SOC) of the battery as the equilibrium index, a simulation model of six series lithium batteries was built in Matlab / Simulink. The experimental results show that after a period of internal group equalization and different groups equalization, the SOC of each cell in the series lithium batteries reaches 100% without causing overcharge. The equalization time is short, and the effects is perfect.