The invention discloses a low-frequency oscillation regulation and control method for a doubly-fed fan grid-connected power system. The method is characterized by comprising the steps of constructinga small-interference linearization model of the grid-connected power system containing a fan, constructing a branch mode potential energy function, constructing oscillation cut set energy function sensitivity, and selecting a low-frequency oscillation regulation and control object based on a mode energy sensitivity function, so that the energy function is combined with a small interference mode concept, the selection of the low-frequency oscillation regulation and control object based on network information is carried out from the perspective of branch mode potential energy, the application inthe grid-connected power system containing the high-proportion doubly-fed fan is explored, and the method has the advantages of being scientific and reasonable, being simple and accurate in calculation and high in engineering application value, being easy to implement, and the like.