In view of the problem that the application scenarios of the slope gravity energy storage system (SGESS) under different grid-connection modes are unclear, the power response characteristics of the SGESS based on three grid-connected topologies including direct grid connection of electrically excited synchronous motor (EESM), doubly-fed induction motor (DFIG) and full power converter were studied. The torque characteristics of SGESS are established and the control strategies are proposed. The power response characteristics of SGESS are studied based on the PSCAD/EMTDC simulation platform. The simulation results show that the power response speed of SGESS based on EESM grid connection completes in a few minutes and the power adjustment accuracy is biased. The power response speed of the DFIG grid-connected system reaches in a few seconds and the power adjustment range is small. The grid-connected system of full power converter can complete a wide range of power adjustment and the power response speed reaches in a few seconds. This work can provide a reference for the technical research and engineering application of SGESS in the future.