Abstract: Research a novel transformerless dual-mode voltage source inverter（VSI）in which the common ground structure shortcircuits the parasitic capacitance and theoretically completely eliminates leakage currents. The inverter consists of a switching-boostbuck（SBB）module integrated with an LC filter network and has a good symmetry of the output waveform. The proposed topology features a wide input voltage range to meet the grid voltage gain,a compact structure,and a simple modulation strategy. Meanwhile,the SBB module allows for soft charging and current stress control within the permissible range. The structural characteristics and operating principle of the inverter are described in detail,a closed-loop controller is designed. The final study results show the feasibility and good performance of the proposed VSI.