Abstract：Aiming at the low voltage ride through（LVRT）problem of the combined grid-connected system

with new energy-energy storage under the control of the grid-forming converter，an additional voltage limiter

control scheme based on the traditional LVRT was proposed. Firstly，the shortcomings of the traditional LVRT

strategy based on current limitation was analyzed. When the fault duration is long，only setting current limitation

would easily lead to synchronization instability. Then，an improved LVRT strategy with additional voltage limiter

was proposed to suppress the fault current under a longer time scale and improve the synchronization stability under the fault. Finally，a simulation model of new energy-energy storage combined grid system was built in Matlab/Simulink to validate the proposed scheme. The experimental results show that the proposed scheme can ensure that the new energy-energy storage combined grid-connected system not be taken off-grid during the three-phase symmetrical sag fault，and effectively improved the synchronization stability of the system during the fault.

      Key words：grid-forming converter；new energy-energy storage；low voltage ride through（LVRT）；voltage

limiter；synchronization stability