influence of environmental problems and resource exhaustion problems, the method of applying distributed generation in power systems is gradually being widely used. However, in large-scale interconnected power systems, low-frequency vibrations caused by mechanical vibrations of power devices and disturbances in a certain system will affect other modules connected in the same system, thereby affecting the stability of the entire power system. In order to eliminate this kind of inter-regional influence, maintain the stability of the power system. This paper attempts to design a control method based on VSG. VSG is often used in power systems where there are distributed power sources such as solar power generation for renewable energy generation. Because this kind of distributed power source does not have the same inertia as the synchronous generator, so when the system is disturbed, the overall stability of the system will deteriorate, and the VSG has the ability to track the maximum power point, which can make this type of distributed generation have the same inertia as the synchronous generator. When the stability of the small system changes, the overall system can still remain stable. This article will focus on the effect of the VSG on the transient stability of the large-scale system. Through the establishment of a simulation model, and verify that the whole system can keep stable due to the function of VSG when fault or disturbances occur in the system.