柔性互联装备中零序电压注入的相间功率均衡控制.

The multi terminal flexible interconnection equipment with cascaded full bridge and dual active bridge structure could connect AC power grid and multiple DC power grid, and instantaneous power differences in different DC power grids and sub module faults could lead to unbalance grid current and DC capacitor voltage distribution. For the three-phase star interconnection structure, this paper adopted the control strategy of injecting zero sequence voltage to meet the different power requirements, derived the specific zero sequence voltage component expression, and quantitatively analyzed the limitation range of injected zero sequence voltage. Finally, a simulation experimental platform was built to verify the effectiveness of the method. The simulation results indicated that injecting zero sequence voltage on the basis of the normal control architecture can allocate the power between phases to ensure grid current balance, reduce imbalance from 6% to 1%,and maintain the even distribution of DC capacitor voltage. [ABSTRACT FROM AUTHOR]