Virtual Synchronous Generator (VSG) has drawn much attention in enhancing the stability of microgrid and overcoming impact of traditional grid-connected electronic devices. In the existing VSG, the active frequency control will result in permanent frequency deviation when the microgrid runs off-grid, which is harmful to the stable operation of the frequency-sensitive load. Therefore, a method of frequent deviation-free regulation is proposed, the frequency deviation generated by the VSG is superimposed to VSG active frequency control loop, eliminating the micro-grid frequency deviation. For microgrids with multiple VSGs operating in parallel, each VSG does not require communication and is independently involved in the microgrid frequency regulation. At the same time, the load power can be automatically allocated to the VSG according to the rated capacity of VSG, conducive to the economic operation of the microgrid. Finally, taking three VSG parallel operation as an example, simulation demonstrates the validity and practicability of this control method. This work is supported by Hunan Provincial Education Department Funded Scientific Research Projects (No. 18A348), Hunan Provincial Self-study Fund Projects (2019JJ40059) and Research and Development Program in Key Areas of Hunan Province (No. 2019WK2012).