Abstract: The Virtual Synchronous Generator（VSG）technology has been widely studied because it enables the inverter to imitate the operation mechanism of synchronous generator,which not only makes the distributed generation access to the power grid friendly,but also enhances the stability of the power grid. However,the traditional VSG control does not have the ability of low voltage ride through（LVRT）because it is difficult to provide controllable reactive power. When the voltage drops due to a remote fault,it is difficult to provide reactive power support and is prone to current overcurrent. To this end,this paper proposes a low voltage ride through control method that takes into account mode switching.First,based on the establishment of the VSG control mathematical model,the VSG control is adopted for the converter,combined with the traditional LVRT control method,the VSG low voltage ride through control method is designed,so that the VSG provides reactive power support during the voltage drop. This control strategy can show the dynamic characteristics of traditional generators while adding low-pass characteristics to improve power supply reliability,help the converter to survive the transient process,and at the same time meet the grid requirements during the low voltage ride-through period. With Flexible Power Electronic Switch（SOP）as the research object,a simulation model is built using PSCAD/EMTDC. The simulation results verify the correctness and effectiveness of the proposed method.