Abstract: During the operational status from off-grid to on-grid in the reconfigurable battery energy storage system, the response time of high frequency power electronic switches has a certain impact on the on/off-grid control. Therefore, a reconfigurable new energy storage on/off-grid control strategy considering the response time of high frequency power electronic switches is proposed. Firstly, a new reconfigurable battery network structure based on switch bypass is designed, and when the reconfigurable battery energy storage system selects the appropriate battery pack for series discharge based on load demand, the constraint condition of the output power and terminal voltage of the battery energy storage system is provided. Secondly, considering the response time of high frequency power electronic switches and combining the pre-synchronization control of the virtual synchronous generator(VSG), a reconfigurable new energy storage on/off-grid control strategy is proposed to achieve seamless switching of the reconfigurable new energy storage off-grid. Finally, a simulation model is built in Matlab/Simulink to verify the proposed control strategy. The results show that the proposed control strategy can achieve smooth switching from off-grid to on-grid mode of the reconfigurable battery energy storage system.