In order to fully tap the potential of the excitation system in improving the power system transient stability，the transient process five-stage excitation control strategy is studied and improved.Based on the power system analysis software package（PSASP），a whole process excitation control model is built and applied to multiple generators in the actual large-scale power system.Simulation analysis under different fault conditions in Sichuan power grid and Shanxi-Henan-Hubei ultra-high voltage（UHV）link near-end shows that the whole process excitation control can effectively reduce the first swing amplitude of the power-angle，and stabilize the grid voltage level.The whole process excitation control plays a positive role in the recovery process and is able to enhance the power system transient stability.