The proposal of global energy internet has stricter requirement to the microgrid interconnection technology. In this paper

the study on the application of back-to-back VSC technology to the microgrid interconnection is proposed through the analysis of before and after microgrid interconnection and its interconnection operation characteristics and also on the basis of deep study of voltage source converter（VSC）.It is shown by the study that the application of back-to-back VSC device to the microgrid interconnection switch achieves fast interconnection with less impact

has good isolation

independent and flexible active and reactive control

stabilizes microgrid voltage

increases stability of microgrid operation and improves power quality.