The virtual synchronous generator (VSG) control strategy is beneficial to improve the damping characteristics of the system. However, the traditional VSG control method based on droop characteristics can lead to static frequency deviation for the frequency modulation. A kind of enhanced VSG control strategy is described in detail in this paper. The static frequency deviation can be eliminated. And the secondary frequency modulation can be realized within 0.5 seconds. A Matlab model is used to simulate the operation of working load fluctuation under isolated island operation mode. The simulation result shows that the design is feasible.