Abstract: The existing new energy stations based on the traditional grid-following control can hardly adapt to the weak grid. Retrofitting some units with a grid-following/ grid-forming switching function can enhance the station's operation capability with a weak grid and avoid the problem of sub-synchronous oscillation. Firstly, this paper establishes a network switching model to achieve an undisturbed switching of grid-following and grid-forming. Secondly, this paper analyzes the stability characteristics of the new energy power unit under the grid-following and grid-forming control, and then the operating short circuit ratio is chosen as the switching index of the grid-following/grid-forming control. Thirdly, a new energy station switching scheme based on the operating short circuit ratio is proposed, and the optimal configuration method of the switchable unit is proposed. Finally, the rationality and superiority of the proposed configuration method are verified by simulation examples.