Abstract: In order to solve the problem of low-frequency zero-sequence circulation current in multi-machine active neutral point clamped（ANPC） three-level grid-tie DC to AC inverters widely used in high-power distributed power generation systems, a new virtual large medium zero vectors modulation（VLMZVM） strategy based on virtual large vectors is proposed. By establishing the zero-sequence circulation current model of multi machine ANPC three-level grid-tie inverters, the generation mechanism and influencing factors of zero-sequence circulation current are analyzed. By detecting the status of zero-sequence circulation current, the virtual large vector or actual large vector synthesis method is selected in real time to suppress the zero-sequence circulation current, and the vector distribution method for distinguishing odd and even sectors is proposed to quickly select the synthesis vector. The experimental results show that the new VLMZVM strategy can effectively suppress the circulation current in the current mutation, parameter inconsistency and full power factor range.